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[Question] [ In the book [*He Drank and Saw the Spider*](http://alexbledsoe.com/books/he-drank-and-saw-the-spider-an-eddie-lacrosse-novel/), a poison is talked about in a metaphorical way: A person can be poisoned by putting a specific kind of spider into their cup, but the poison only works if you drink and then see the spider. If you don't see the spider, then nothing will happen. The book used it as a metaphor, but how could a poison like that exist, where it only works if you know you've been poisoned? The book is fantasy, with magic being a thing, but it is very rare in the universe. [Answer] When you are startled, it causes a physiological reaction. Make the effects of the [startle reflex](https://en.wikipedia.org/wiki/Startle_response) a necessary aspect. I know it can make your heart race, and probably dumps adrenaline or something. So the ingested toxin, after it has time to get into the blood, but before it is cleaned out, needs the victim to have an adrenaline dump event. That’s why it’s associated with the empty cup — to get the timing right. The toxin can be activated by adrenaline or other hormones associated with a fright, changing form and becoming the actual toxin; or it jams the receptors that are now in-use because of the startle, or any number of variations. So use one that’s properly metaphorical; e.g. by jamming the receptors he is literally scared to death. It could be a drug developed for use in aversion therapy or extending the fight-or-flight reaction boost in soldiers. But overdosed or used on someone who is in less than ideal health, it’s fatal. [Answer] # The antidote triggers — or is — the poison If you are looking for a purely mind-activated poison then you are not likely to succeed, no. However, if you can make the subject think they have been poisoned by a particular substance, **and this forces them to take an action to counter that poison**, then you have a pretty much open playing field. Two scenarios then... Either the poison is a two component poison, and the antidote in combination with that which was ingested triggers the reaction. Or the antidote is in fact toxic if an the actual toxin is not present. Some nerve agent antidotes can work this way. Do note that in both cases it is not necessary that you have been **truthful** about what substance the victim has ingested, or even if they actually have ingested it or not. You only need to make them **believe** they have. [Answer] **The spider secretes the poison, but contains the antidote.** If you drink the drink and see the spider, you're unlikely to decide to consume it. If you don't see the spider, you would most likely just consume the spider as well, ingesting both poison and antidote. [Answer] You are probably looking for a [nocebo](https://en.wikipedia.org/wiki/Nocebo). > > The nocebo effect is when a negative expectation of a phenomenon causes it to have a more negative effect than it otherwise would. A nocebo effect causes the perception that the phenomenon will have a negative outcome to actively influence the result. Mental states such as beliefs, expectations and anticipation can strongly influence the outcome of: disease; experience of pain; and even success of surgery. In the narrowest sense, a nocebo response occurs when a drug-trial subject's symptoms are worsened by the administration of an inert, sham, or dummy (simulator) treatment, called a placebo > > > I can confirm it works: when I was still at the university there was a fellow student who was paranoid about being poisoned by breathing organic substances we used in the lab. One day, to play him a prank, we wrote on the whiteboard "organic cabinet has been opened" (it was normally under vacuum, as the organics we used where pretty reactive with oxygen and moisture) when he was in the testing room. As soon as he came out and read the whiteboard he started feeling sick and had to be accompanied to the ER, where despite we told the doctors it was only a prank and no substances were present in the lab he insisted in being unable to breathe properly. [Answer] ### The cup contains both poison and antidote. The poison is lower density, and thus at the top of the cup. You drink this first. The antidote is much higher in density, and thus sits at the bottom of the cup. This will only be drank if you finish the cup. If you see the spider (wives tale or not), you aren't finishing that drink. You don't drink the antidote. **edit** Just for fun, here is a picture of a cocktail I helped develop a few years back. The little balls are spherized chocolate liqueur. They are sitting on top of a dense white chocolate liqueuer, on top of which is a white spirit/liqueur mix, the higher alcohol content makes this much less dense. There is an invisible line (because they are both clear) that can only be seen if you have it at the correct angle, or if you rest tiny chocolate spheres in between the two liquids. The top mix is as clear as the bottom liqueur, but because we shake with ice, it creates condensation on that part of the glass if left in a warm room to take photos. Drinking does not mix the liquids. Stirring does. [](https://i.stack.imgur.com/cRfNK.jpg) This is not my photo, but it is the same drink. [Answer] JDługosz had a good idea by using the startle reflex to cause chemical changes in the body which make the poison potent. However, the startle reflex is a bit to broadband for this to be sufficient. Someone could simply sneak up behind you and pop a balloon to cause the startle, letting poison take effect. However, the startle reflex is only one of many reflexes we have, and some of them are far more nuanced than a mere startle. It's known that digestion starts with the eyes and the nose. As you see and smell food, you actually start prepping the digestive enzymes needed to digest it. You'll generate the correct set of digestive enzymes for the particular foods you smell. This effect could be used to generate a particular cocktail of enzymes which you only produce once you know what you're getting. A similar pattern appears in bee stings as well. If you are allergic to bee stings, the first sting is not all that dangerous. You puff up a bit, but it's not all that bad. However, the second sting can be very fatal because your body now knows what it's responding to and has hyper-attuned itself. Some effect between these two extremes is probably what you are looking for. [Answer] ## Use the nocebo effect's biochemistry to *trigger an actual poison* The nocebo effect is documented to work through a reduction in dopamine and endogenous opioid levels in the brain's pleasure centers. This could be used to trigger a poison -- the poison only works on, say, a dopamine receptor type if the dopamine levels are depleted by some other external factor. In a sense, it'd be the opposite of a "silent antagonist" where the antagonist only works if the receptor is binding a ligand. While this requires complex biochemistry understanding to pull off, it'd be fairly reliable (compared to relying on the nocebo effect alone) and would allow for a broader range of effects as well, especially if the change from the receptor+ligand+poison complex to receptor+poison causes the chemical lysis of part of the poison, releasing a much more toxic fragment such as a superoxide, hydroxyl, or 1,4-didehydrobenzene radical that can go on to do severe damage. [Answer] There is no poison! Or there is! Basically, there is no such poison. You just make everyone think there is. Think about it. You have a poison that never works if you don't know you were poisoned, but always works when you have been poisoned. The only way to know **FOR SURE** that you were poisoned *is to be dead*. So, how does someone get this myth going. Simply, you claim that you have such a poison, and then use some real poison of some individuals. Make sure, after they have been poisoned, that they realize it (make it easy, or obvious, or use a whole lot of discrete suggestion), then get these events some publicity. If anyone later thinks that they were poisoned, just tell them that you didn't poison them, and they therefore survived. When you want to use this poison, simply make sure that it is noticed. So, basically, IT IS A SHAM. There is not a spider in every cup. Those who never realize they were poisoned never were. You just have to make sure that every real victim gets enough publicity to the fact that they realized they were poisoned for your fantastic story to continue. Ultimately, dead men tell no tales, live men must not have realized or not have been poisoned. It is up to you, as the man behind the curtain, to decide which! [Answer] It isn't really the knowledge that kills you, although it appears that way: The drink contains one component of a compound poison, the other component is released from the spider the moment it is exposed to air (ie., you have emptied the cup and the spider is plain to see) and needs then to be inhaled - your nose needs to be directly above the cup, so you see the spider. If you just drain the cup on the floor, the second component is released too far away from your nose and dilutes too much - hence the appearance as if the look at the spider kills you. Don't use this on a blind person, or you'll spoil the trick. [Answer] Psychoactive drugs can work in quite specific ways. For example, the parasitic fungi Ophiocordyceps unilateralis and Toxoplasmosis gondii alter the behaviour of infected ants and cats in ways that benefit the parasite; mescaline and LSD each cause humans to visualise distinctive, recognisable types of image. So I don't think it would be impossible to believe that a spider's venom could be more or less harmless, yet cause you to have a fatal seizure / apnea / heart attack / suicidal compulsion on seeing the spider's specific pattern of markings. [Answer] As always with those questions: If someone knew how to make it, someone would make it. There have been a couple of answers around placebo-like effects and panic attacks and such (which also was my initial thought), but the obvious problem would be that those do not even need the substance itself and the image alone might be enough to kill. So we have to get pretty sci-fi here: We know nothing about our brain. But if we did, this would be a possible task. Let's take your spider example. We have a memory of a spider - if we see it, something in our brain is activated and it has been theorized that it comes down to a singular cell - or something like that. If we had a highly targeted drug that could infiltrate a single, specific cell (or area or whatever you need) and if that cell is triggered does X - this could be enough. X could be deadly on its own or you take a mix that becomes deadly once X has happened. Maybe this could be done with a specific image, maybe just any spider or even thinking about a spider (for example the word "spider" could trigger the response) would be the only option. It could be done in theory, but maybe our grand-grand-children will be murdered like that. Oh, please be aware that this could differ from human to human. Maybe that poison has to be designed for each target specifically. Maybe this is even more awesome. I think so Also note from the comments: For pseudoscience / handwaving in a story, one could look into “NLP" [Answer] **The poison is made up of microscopic robots.** These robots are all linked up to each other in a hive mind and when they are drank they scan the brain to see if it knows that what was drank is poison. If the brain knows that poison was drank these robots start attacking the nerves and killing them but if the brain doesn't know that what was drank is poison these robots pass harmlessly through the digestive system. [Answer] The spider is aquatic (these exist naturally so its not a stretch to have that). Its exoskeleton (or something naturally on or released onto its exoskeleton) becomes oxidised upon exposure to air. An old nurses tale says that this spider comes to judge good and bad people, and to quickly drink a glass of ale and swear allegiance to god, so that if it's death the spider brings, then they die in a state of grace. Unfortunately the oxidised compound is highly soluble and dissolves in the last of the drink, thereafter reacting in the stomach with ales made from a particular process or crop, and becomes fatal even in microscopic doses. (Also plausible - cross reference ricin, ergot - I think - and other spoiled wheat/barley toxins). This allows a slightly different scenario from the rest, where it's the combination of seeing the spider, and traditional folk belief (with their usual grain of truth) which is fatal. Enough people die - and enough don't - to sustain the nurses tale. But someone who has worked it out would be able to check (or ensure) the ale to hand when the victim called for ale, was the kind which wouldn't be survived (assuming it isn't the same beverage that was in the cup). The spider being aquatic is not commonly seen and maybe even a bit mythical if very hard to find, but provided it can cope with the beverage in place of water, this explains why the spider is okay in the drink as well. It could even be that the spider is imagined to magically appear, and the idea that it was put there by an individual would be sacrilege or "beyond the pale". The main "hard science" stretch is whether enough can oxidise and dissolve in the short time available at the end of a drink. An alternative might be that the toxin doesn't need to oxidise. Instead it's a little denser than water and tends to accumulate in the bottom of the drink, where the spider has been exuding it, and the tiny dose is mostly concentrated in the last dregs of the drink. So it isn't seeing the spider that does it. Its the fact that only a person who sees the spider, has *also* just drained the last part of the drink in their cup (which exposes it to their sight). Variations on these ideas allow quite a flexible range of scenarios. [Answer] What about a reverse cause and effect? The spider, wary of this person who's rocking its current residence all of a sudden, will consider itself hidden and out of harm's way, until a direct look is cast by the drinker, in its direction. As long as the drinker minds his own business, so will Spidey. He's just a photo-shy guy spider. If and when he gets stared at - Spidey panics and, outraged at the indignity of it all, attacks. Of course, you'll need a certain amount of intelligence/conditioning/valid evolution for a don't-look-at-me spider, but there are plenty of examples in the animal kingdom. [Answer] # [Nocebo](https://en.wikipedia.org/wiki/Nocebo) Did you hear about the [placebo](https://en.wikipedia.org/wiki/Placebo) effect? Well, it's almost the opposite. Placebo effect is when a doctor (or shaman) gives you an aspirin (or "magical water") to heal you from a sickness, wound or pain when they are fake (flour aspirin or normal water) **but** your wound, sickness or pain are healed (this effect is more common with pain). **This works because our brain think that you are healing and it removes the pain or forces your body to heal that.** Nocebo is the opposite. When you take an aspirin (real or fake), it has a written secondary effect (e.g: stomach pain) and you have them, **even if these secondary effects are false** is called nocebo. This work in a very similar way that placebo but with the opposite effect. **A real example was tested with a prisoner:** I have no idea when it was, where or with who but it's real. Edited: It was done by a scientific of Phoenix in the penitentiary St. Louis, Missouri. [More Info](http://www.forodeseguridad.com/artic/reflex/8078.htm) (Warning: Spanish). Once upon a time there was a prisoner with a death sentence in the electric chair. He would be killed in a few days but a scientist proposed an experiment with the prisoner. The scientist would try to kill the prisoner with a lethal bleeding but there was a chance of survival, the prisoner accepted (he has a chance of survival and if it wasn't true he would at least die painlessly). He was tied to a chair and the doctor made a **little cut in their wrists** (this cut was so little that it didn't cut their veins or arteries -doesn't bleed- but the prisoner didn't know) but **he said to the prisoner that he will start to bleed**. To make this more real he put a serum bag, dropping the serum (drop by drop) into a metal cube so the prisoner could **"hear the sound of his own blood dropping into the cube"** (this was fake so he put the bag and cube outside the visual range of the prisoner). Every 10 minutes the scientific approached the prisoner ("checking the status of the patient") and **closed the serum bag a little** (making each time fewer drops). Almost 2 hours later he closed the bag completely (so, no more drops) and a minute later **the prisoner fell unconscious and his heart stopped beating**. This is because his brain thought that he lost all his blood. You can convince your victim that they will die with a poison. To make this more realistic you could put non-lethal poison (something that makes you feel sick so they would think that there are poisoned). # Chemical reaction Your poison could work with a chemical reaction. * Maybe your poison could have a **reaction with the adrenaline** and then it becomes poisonous. When you said to someone that he would die he will **release adrenaline** and it will make a lethal reaction in their bodies. * Or you poison make a reaction with 2 components, **one the poison and the other the antidote**. Only persons who think that there are poisoned would drink/inject the antidote and make the full reaction. + Even your poison could be nothing and your **antidote is the real poison**. # Magic / Sci-fi * Nanobots: the poison is nanobots, their read your neuronal connections, when you know that you are poisoned they turn on their body destruction mechanism. * Quantum mechanical: a "quantum poison" is made of particles simultaneously be two different things: *nothing* and *the poison*. These particles are two things at the same time, but when you said that they are poisoned the particle now is *poison* and can't be turned into *anything* anytime (because you said what it's), and if you said that it's nothing the particle would be *nothing*. [Answer] It depends on what You exactly mean by "exist" and "works". There are very real and very strong psychosomatic effects in our real world. You can think something like "placebo effect" inverted. Knowledge about being "poisoned", if you are deeply convinced, can make you contact an illness or shock you to death. Of course reliability of such a method can be questioned ;) ... unless you rely heavily on magic of some sort. [Answer] ## Quantum superposition poison [Quantum mechanics](https://phys.org/news/2015-01-atoms.html) allows for particles to simultaneously be in [two different states at the same time](https://en.wikipedia.org/wiki/Introduction_to_quantum_mechanics). This can be thought of as being in two places at once, or travelling two different paths at the same time. It is not until an observation event occurs that the particle must decide one or the other. See the links for more details and pretty pictures on the specifics how this was proven to be true, even though we still [don't know why, or how](https://en.wikipedia.org/wiki/Quantum_mechanics), exactly. In any case, given that particles, and atoms can exist in such a state, it should be theoretically possible for a molecule to also achieve such a state, namely, a poison molecule. Now, this molecule could have the particular property of being non-poisonous in when it is still in a dual quantum superposition state, but poisonous should it leave said superposition state and enter into one of the non-superposition states. This would achieve the desired affect scientifically, even if the development, storage, and deployment of such a substance is well beyond current scientific capability and is purely a theoretical exercise. **Example** Going back to the story cited in the question, the act of observing the spider triggers awareness or knowledge of the presence of the poison, which could very well suffice as the "observation" event needed to collapse the quantum superposition substance into an actual particle/molecule, and thus poison the person upon observing the triggering object. [Answer] It's a very plausible idea that a drug could have different effects depending upon how the brain responds to changes. For example; Heroin drug users are often at risk of overdosing if they take the drug in a different environment. There have been many cases where users have died from overdoses after taking the same amount after moving to a new home. There are many papers on the subject: <https://www.sciencedaily.com/releases/2000/10/001012074704.htm> There are also many different kinds of ways drugs activate. Not all drugs trigger different responses at different doses. Some drugs have no effect until you reach a specific dose amount, and taking any more after that has no further effects. Some drugs reverse their effects when you overdose. For example; some sleeping pills will act like a stimulus if you overdose. Keeping you awake and hyper. Some drugs reach a high point of effectiveness at higher doses, but taking more resets the effect back to zero. You have to take even more to increase the effect again. So it's possible. Using these facts about drugs that you could create a designer drug that "appears" to work like magic. Maybe you keep giving a person a drug in secret with a tea cup. They build a tolerance to the drug as you slowly increase the dosages over time. One day you introduce the spider to the cup. At first they drink the tea with the drug and not see the spider, but one day they see the spider. This triggers a change in environment and they loose their tolerance for the high dose of the drug. They overdose as a result. To everyone else. This looks like strange magic. [Answer] This may work this way: the poition makes your heart very vulnerable to any stress, so it stops at any panic or fast movements. If the person does not know he was poitioned, he is relaxed and everything goes as usual. But if he sees the spider he comes under immediate stress and his heart stops. [Answer] # Epilepsy It's not quite a poison, it is really far-fetched and it's not really reliable, but one possibility would be to trigger an epileptic seizure, if your victim suffers from epilepsy. And flickering light is known to trigger seizures, so you can make your spider shiny and flickering (and the adrenaline would likely contribute to the seizure). But more reliable would be to just put flashing magical LED light at the bottom of the cup, activated by air. [Answer] I especially like the answer using the 'observer effect' within quantum mechanics, but unfortunately non-determinism applies to both actors in this scenario so there would be no quantum mechanical way to be 'sure' the target was poisoned (independent of any action or inaction on their part). I would suggest the method used by illusionists regularly which is to use misdirection to effectively poison the target by their own actions (I'm not suggesting Illusionists poison anyone, rather they simply encourage the audience to assist in the act of creating the illusion for themselves). In a relevant example, one could add a precursor or uncatalyzed poison to the drink. If the drinker does not see the spider then the poison passes harmlessly through the biological system and is excreted. Yet if the drinker sees the spider, some cultural-ethnic-habit-superstition-religious action (the action being completely normal, acceptable, predictable, and normally harmless) causes the activation of the poison compound and thus ultimately their fatal poisoning is the result of their own actions. Refer to the practice in some ancient cultures of using a silver implement to eat one’s food in the house of a stranger… the cultural belief being that if the unknown hosts are trying to poison the guest, the silver would turn black. Similarly, If one were to poison the cup with the spider being seen by the target, then they would reasonably not eat the meal which ironically contains the deactivating antidote… conversely, a scenario where the target sees the spider in the cup causes the target to rush outside in search of wood-mushrooms which in his/her culture are medicinal, yet in this land they are very much fatally poisonous. To me it is very suggestive of a Poe classic: ‘The Cask of Amontillado’ (oldie-but-goody) [Answer] It is the most well known "poison" historically speaking. > > Sin/Evil > > > Now this is technically a tad bit subjective, but let us consider this: 1. many religions say that sin is the ultimate cause of mortality (as in the ability to die and stay dead) 2. One cannot accidentally sin. Most things tend to emphasize that the perpetrator actually does something *wrong and knowingly so*. After all, that is the dictionary definition of the word. I think this qualifies. It is a bit of a stretch and isn't a physical poison. However, a mental poison that has a 100% mortality rate with no known cure to prevent death (nobody says anything about staying dead) is certainly a reasonable thing to look into. Also, it is worth noting that without the presence of this poison already in place no other poison will be successful. They will always fail. So in a roundabout way this means that this is the only poison that actually will work and requires one to know they have been poisoned... and willingly accept the poison. [Answer] Maybe it's a kind of a nocebo effect (negative placebo). Think of it that way: The person who takes the drink and does not see the spider, doesn't loose a thought on being poisoned neither. Thus, everything will be just fine. But if that person sees the spider, the person starts to worry about the possibility that someone just poisoned her. This leads to a physical reaction and the activation of the "poison" which now causes real physical symptoms. [Answer] Maybe, similar to other answers, the poison in the cup is actually benign until mixed with another substance. The person drinking the "poison" is led to believe, or perhaps comes to know through faulty research (or maybe even deceit), that the antidote is a certain chemical. However, the "antidote" is what activates the poison and kills them. Hence, if they know they're poisoned, they will seek out a cure, but the cure kills them. If they are oblivious to the "poison" nothing happens as it is benign. [Answer] In a real world situation this would have some real benefits and quite possible with the upcoming nanotechnology. The body could encapsulate any unwanted drugs so they would not be absorbed by the stomach unless confirmed with the Host. In the stomach would have be a form of communication device where the host could deny or allow certain chemicals to be absorbed into the body. This would definitely prevent any date rape drugs. [Answer] A poison typically works independent on whether you know about it or not. If it shall only work if you know about it, it would have to be able to literally read the mind (nocebo effects or cheating by faking the poisoning and then waiting for the person to make a mistake are not very specific and might easily fail). The usual chemical compounds cannot do that, so either you have to use advanced technology (like the nanorobots of [Anders Gustafsons](https://worldbuilding.stackexchange.com/a/83525/6314) answer) or magic. A magical solution could for example be: * Once you know you are poisoned your magic automatically searches for the intruder and thereby triggers a fatal reaction like the poison starts to depress you or kills you right away or it's just some sort of evil magic that can only work if you know it's there. * Other endless possibilities. ]

[Question] [ **Closed**. This question is [opinion-based](/help/closed-questions). It is not currently accepting answers. --- **Want to improve this question?** Update the question so it can be answered with facts and citations by [editing this post](/posts/10017/edit). Closed 5 years ago. [Improve this question](/posts/10017/edit) Let's assume that : * The scientifically proven god is omnipotent and omniscient * The god stays as how it was acting even after the proof, meaning natural disasters still occur, the speed of light is still the way it is, and the sun still rises in the east and sets in the west. * The god is a singular, immortal being Sadly, I cannot think of a scenario how this could be proven, but that's the point of Worldbuilding.SE right? How would believers of other religions react to this? How about atheists? Would monotheistic religions be abolished if the proven god isn't theirs? How would society at large react to this? How about the law and government? --- Additional notes : * For this specific case, let's assume that there is empirical proof, rather than philosophical or theoretical proof. * To cater to polytheistic religions, the "singular immortal being" assumption is that there is ONE god that has been proven, but that doesn't mean they have proven the non-existence of other beings like it. [Answer] If science proved that there was *a* God, the first thing everyone would try to do would be determine if he was *their* God. Depending on the nature of the God and how it's proven that he exists, this may be easy or hard to do. During the period in which everyone was still trying to determine which God he is, there would be a host of reactions. Some believers of monotheistic religions would proudly exclaim that of course He must be their God and by extension of course everything that they believe must be true. Some would be happy to know for certain that God exists and expect to learn more about what is really expected of them, as well as being able to have all the confusion cleared up. Some would be paranoid and believe it to be a trick, either by the devil or by the people who proved God's existence. For polytheistic religions, I imagine it would be similar. Some people would take it to mean that since one God exists their other Gods must also exist. Others might be worried that one of the Gods is getting uppity and trying to seize more than his fair share of power, leading those people to be worried about a war between the Gods devastating the Earth. Because people are people, atheists would also have the same continuum between belief and disbelief. After they got used to the idea, some would be pleased to know that there is a God after all. Others would stubbornly refuse to accept the proof, finding ways to convince themselves that there must be some flaw with the proof or that it is an elaborate scheme by religious groups to sucker them into believing with the end goal of completely controlling them. This by no means a comprehensive list of how people would react, but hopefully it gives you an idea of how diverse the reactions would be. In general, how many of each group believe what will depend on the manner of the proof. If the proof is showing that pi, starting from its 100-zillionth digit, is actually an encoding of the sentence "Hi, I'm God. I exist, yo" followed by the collective works of Shakespeare (or something else that helps prove it isn't just random noise), then it's likely that few people would change their opinion of God based on it. If the proof was God showing up and telling everyone in the world "Hey guys, what's up?" before going back and doing his normal gig, then most people would believe. Once it is determined whose God he actually is (with the option of him actually being one that nobody specifically believed in), some appearances will change quickly but realities will only change slowly. You specifying that God's behavior is the same as before the existence proof implies that while we now know he exists, we still don't know exactly what is expected of us. Religions will shift to include that God as their God (or one of them), but still teach that they are the ones who know what God *really* wants us to do. You'd still have just as many religions as before. Some people will get frustrated by not being able to get God to tell them exactly what to do or have him explain why things happen. Those people will get angry with God and believe that he doesn't care about humanity at all (which might be the case with the God you choose), causing them to leave whatever religion they were in and be the new atheists. As I mentioned, some people would still not believe in God, but the "new atheists" would be people who believe God doesn't care about us so they can do whatever they want to without fearing punishment from God. Some people will take events as a sign from God (tornado missed your house? Must have been God blessing you, rather than just random chance), causing them to become more religious. The scientific community, knowing that God exists, would want to empirically prove God's doctrine to make sure that we got it right. However, since God's behavior hasn't changed they would just have to continue doing what they'd been doing. We would probably take it that "doing what God wants = happiness" so if something makes us happier then that must be what God wants. This would lead sociology studies to become more important - if behavior X makes people happier, then that must be what God wants us to do, so we should do our best to figure out what which behaviors do that. In my opinion, the most interesting part of this would be what would happen in later generations. Even if the proof was something constantly there (such as God sitting on the moon, occasionally waving to the Earth, visible to the naked eye), over time people would grow to hold it less important. You'd have more and more people join the "it's a government conspiracy!" crowd, as well as people who join the "God doesn't care so much about what we do, so let's party!" crowd. If the proof was a one-time event then, even if it was significant enough to cause *everyone* to believe it, people will still stop believing over time. Some teenagers will still rebel against their parents, leading to them intentionally not believing just to be contrary. As time goes on the group of people who no longer believe will grow to the point where it returns to what we have today. [Answer] Jesus said, "If you were blind, you would not be guilty of sin; but now that you claim you can see, your guilt remains." From this principle it is clear to a Christian that God's behavior is proportionate to the amount of religious knowledge that an individual or society possesses. Thus if a scientific demonstration of God's existence were given, a Christian would say that God would now hold the world responsible for that knowledge. His exercise of judgment against evil would increase, as would his reward of virtue. His actions would be less hidden and more clear. The fascinating thing is that the Bible has an account of what happens to a culture when a scientific demonstration of God's existence is performed. That story is the account of the Exodus from Egypt. Consider that Moses predicted ten plagues over the course of several months and each occurred. Consider this to be an experiment. The hypothesis was that Moses' god was real, powerful, and would set his people free, and that Pharaoh's gods were false and impotent. Each plague was a separate experiment testing an aspect of the hypothesis. Each plague was intentionally aligned with a different Egyptian god: they worshiped cattle, the cattle died. They worshiped the Nile, and it turned to blood. They worshiped the sun, and it grew dark. etc. As a result of Moses' experiment, some Egyptian's came to believe that Moses' god was the true god, while Pharaoh and other Egyptians persisted in their original belief. I think that if a parallel event occurred in another society, even ours, you would see the same result: some believe, and some do not. As the Jewish people entered the desert, they were punished severely for what we might consider small infractions of law. That was because they had proof of god's existence, hence were held to a higher standard. This is why Christians believe that when Jesus returns to Earth at the end of the world, terrible events will follow. His return will be the scientific proof, the world will no longer have any excuse for unbelief, and final judgment will be necessary. If reward is based on faith, then proof seals everyone's fate. Those who already believed will be rewarded. Those who did not already believe cannot be rewarded and their state cannot be altered, because the possibility of faith has disappeared. In the past, the scope of this knowledge was limited to a few countries. With the internet, TV, radio, books, and other media, should God ever appear persuasively, no part of the world will escape this knowledge and its consequences. Your question is interesting, but have you thought about it from the other side? Religion is mocked because of its exaltation of faith over science. Have you noticed, though, how a science devoid of faith ceases to be science? Having read hundreds of articles defending or refuting the current theories surrounding climate change, it is clear that many people on each side hold to their views not because of facts and sound mathematics, but because of whom they trust for their information. Actual fraud, poor scholarship, tinkering with data, faulty measuring apparatus, calls to ban certain ideas from publication and expel their proponents from their jobs at laboratories and universities have to do with something akin to religious faith, not science. UPDATE: It has been fairly suggested that I clarify that my answer presumes the truth of the Christian religion in order for it to work. It actually does not, and I will explain why. The OP asked how society at large would react to a supernatural revelation. The society of the United States and Western Europe, as well as pockets elsewhere in the world, are philosophically and religiously shaped by a certain understanding of history and faith, the Judeo-Christian tradition. Whether or not the majority culture's belief is true, that is what it believes and is a fair predictor of how its people would behave. Thus if the we believe that the people of Moses' time acted as they did for the reasons that they did, then that is how we are likely to see our society acting if we were in the same circumstances today. Individuals may act differently, but it takes a giant shift in worldview to get a society to change its behavior. Our culture is going through such a shift, but surprisingly, many of the new ideas being proposed are recycled versions of philosophies from the past. Thus we can look at how people holding those ideas reacted when they had shattering encounters with foreign religions (like Christianity or modern science) to see how they reacted. [Answer] ## The real answer **By definition, you can not prove a supernatural god with science. This is why religion operates on faith rather than scientific evidence.** This is *not* a definition of faith, it's why faith has a place in religion. To my knowledge, gods are supernatural. There are so many different gods that I don't think supernatural is a requirement, but this answer assumes you mean a supernatural god. William of Ockham, famous for Occam's Razor, believed the following about one of the many gods of humans (and quite a popular one) - > > "only faith gives us access to theological truths. The ways of God are > not open to reason, for God has freely chosen to create a world and > establish a way of salvation within it apart from any necessary laws > that human logic or rationality can uncover." > > > I would gladly accept scientific evidence, because it means there would be no cognitive dissonance, that *does* sound divine. The problem is that most concepts of a god are, by definition, outside of science. Science operates on the natural world, not the supernatural. Gods are supernatural, above or outside of nature, science has as much place there as it does with questions tagged as 'fantasy-based'. ## The answer you want **Here is the main problem: religions don't have a great history of trust with science.** Assuming you've scientifically proven a god (a label that would no doubt be provided by the media, not the scientists), what you're going to get is a lot of pretty surprised scientists and a vast majority of religions claiming this new god is not *their* god. ***Their* god doesn't fit inside the box labeled *science*.** That's a fair claim, because it/he/she doesn't. In the same way my flying-spaghetti-monster does not, because it's *designed* not to fit. Humans can easily imagine things outside of science, things that are inherently contradictory. ## How would the world change? Things would not be terribly different, people would still claim that they have a bigger god out there somewhere, others would claim they don't, and a new religion would spring up worshiping this new god. Disasters would still happen, no new miracles would be occurring, no new revelation, the new god would answer prayers with the same rate as chance, and the new religion would eventually split into a thousand sects who all despise each other. **Basically, if you change your question to ask about a hyper-intelligent alien, the answer would be the same.** --- **Background: Feel free to skip this part.** I'm an agnostic atheist. Sometimes I jokingly describe myself as a militant agnostic, "I don't know, and neither do you!". I'm not one of those 'mad-at-god' atheists, I'd like to believe, but I can not be happy with that much cognitive dissonance. I don't *know* that gods or a God don't exist, but I don't believe in them. I'm an atheist about all gods or God. Most people seem to forget they're an atheist about other people's gods too, as often as they confuse *conviction* with *knowledge*. I think about the Abrahamic God, Yahweh, the same way most people think about Zeus, it's just modern mythology. I'm not going to apologize if you're offended by that, it's not meant as an offence. If you're offended by someone having a different belief than you, I suggest you examine whether that belief actually makes you a happier person, especially if your belief requires you to be offended... [Answer] This is an interesting scenario, and one that has not been unexplored in fiction. However, you ask, "How would society react if the god of one religion has been scientifically proven?" but then immediately introduce the assumptions that "the scientifically proven god is omnipotent and omniscient" and "the god is a singular, immortal being." For some religions this simply isn't the case - not only with fictional religions, but with actual religions as well. Many early historical religions where polytheistic and didn't attribute things like omniscience or omnipotence to any particular god. For a modern instance, in the Mormon religion, there is not a single God but a hierarchy of Gods, of which only one is "ours". The various Star Trek TV series had more than one separate instance of human encounters with such deity. For instance, Star Trek:The Next Generation introduced the apparently omnipotent and omniscient "Q". He was neither worshipped nor treated with reverence by any significant number of people who encountered him on the show. However, you ask specifically about a whole society. This is explored in Star Trek:Deep Space Nine, where the whole Bajoran society is based on the "prophets" who are essentially gods who live in an artifical wormhole connecting the Alpha and Gamma quadrants. There is proof that these gods exists and live in the wormhole, and their power is manifest from time to time. Despite this proof there are still non-believers (outside of Bajoran society). Are they gods or are they worm-hole aliens? Those who don't believe say the latter. The "emissary" says, "Why can't they be both?" There is a particularly interesting dynamic in ST:DS9 because later in the series we are also introduced to the "Founders" - of non-solid shape-shifters who have genetically engineered a race called the "Vorta" to administer their Dominion, of which the most interesting is the "Weyoun" character. Here are a couple key quotes: ``` Odo [a shapeshifter]: Has it ever occurred to you that the reason you believe the Founders are gods is because that's what they want you to believe? That they built it into your genetic code? Weyoun 6: Of course they did. That's what gods do. After all, why be a god if there's no one to worship you? Weyoun: Pah-wraiths and Prophets. All this talk of gods strikes me as nothing more than superstitious nonsense. Damar: You believe that the Founders are gods, don't you? Weyoun: That's different. Damar: [laughs] In what way? Weyoun: The Founders *are* gods. ``` To answer your specific questions. *How would believers of other religions react to this?* Rivalry perhaps, or dismissal of the evidence. *How about atheists?* Interestingly enough, I don't recall there being any Bajoran athiests, and that society had had actual documented interactions with their gods over time, including supernatural "orbs". So from this standpoint, it's likely that if there were not any cultural differences, people would convert. From a scientific standpoint, the thing that prevents a lot of people from not being atheists is the lack of evidence. If you provided irrefutable proof to Richard Dawkins that God exists, he would have to believe. That doesn't mean that he might not have issues with God, but I don't think he would any longer claim he doesn't exist. *Would monotheistic religions be abolished if the proven god isn't theirs?* Again, this is probably a cultural thing. If a different culture's diety was proven true, this doesn't necessarily provide any incentive for a culture to abandon their own, unproven diety. *How would society at large react to this? How about the law and government?* This probably depends on the nature of the proven deity. For instance, if the God of the Christian Bible was proven correct, then all the other things written in the Bible about how law and government would work could be expected. [Answer] Reactions could be categorized. **Believers in the lucky religion** - no change, other than significant increase in smugness, and also membership. **Believers in other religions** - drop in membership, general sadness. Denial of the evidence as anything other than a test of their faith. **Agnostics** - "Aha, so, we were right. God was a theoretical possibility after all." **Soft Atheists** - admission of being incorrect, expressions of disappointment at the uncovered God. **Hard Atheists, Conspiracy Theorists, Nutjobs** - disbelief of the evidence. **Civil rights leaders, Conspiracy Theorists, Nutjobs** - the Problem of Evil means we must rebel. Sure, more people than before now believe in a god, but is it a God *worth worshipping*? **Average man in the street** - brief interest, but phwoarr, lookitt the jugs on that page three. **Hollywood** - this will make a great movie. A respectful treatment, of course. Tasteful. But who should the love interest be? **Cultists** - now is the time to pour the kool-aid and join our God in the heavens! **Businessmen** - better change the advertising a little to take advantage of this. See if we can lobby for some new laws that ostensibly respect the God, but actually serve our financial ends. **Politicians** - if the voters are going for this God, prepare to follow it if we didn't already. Hey, this evidence... can it be used to our advantage? Is it a source of power? Money? We might need to sequester it, in the national interest of course. Some of our lobbyist friends can get the contract to do the job. **Scientists** - see if we can communicate with this God. There's so much we can learn. **All** - now we know it exists, and is reachable, we must try to find out its weaknesses and how to make it stop existing. I'm sure I've missed some valid categories. [Answer] I would say that merely by proving there is 'a' god you will be proving to all (at least monotheistic religions) that you have proved 'their' god. Unless the being specifically communicates to those it thinks are 'wrong' they will think they are justified. Some of course will claim it is a false god, especially if it looks like they are wrong, everyone else is being deceived by the devil! Polytheists will of course assume that since there is one, there must be more so all is good. [Answer] I think we could probably answer the question by asking, How do we know that (in some way or another) God's existence *hasn't* been empirically proven already? I'm not trying to be cheeky; the whole issue of "faith" is whether one is willing to believe in something (someone?) willingly rather than being "coerced" by some rationale (in the same way that you can't really be in love with someone by being externally coerced). In other words, *the world would probably look exactly as it does now*: people disputing the validity of the proof, those saying that the whole exercise is futile and we should just get on with life, and so on. Probably an interesting line of questioning would be, what exactly would empirical proof of God's existence look like? Literal footprints? Visually seeing and documenting him? Perhaps something more abstract like the fine-tuning of the universe for human life? Perhaps historical events such as him speaking through a prophet and doing things that defy natural laws? As a run-of-the-mill Christian, pondering what empirical evidence for God looks like is to me a compelling reason to believe that he does exist, insofar as the kinds of things a God you described would be able to offer as proof are exactly the kinds of things that are said to have occurred. Of course, this is my opinion. Great question. EDIT: How atheists would react: After some further thought, it occurred to me that most likely, atheists would conceivably support the existence of such a God, because a big sticking point for many is that belief in God is unjustified precisely because it is not empirically proven. Furthermore, many atheists reject the God of the Bible on the ground that interaction with him is superstitious, or that he is morally reprehensible, etc. So I would argue that if the God that was empirically proven were more suitable to modern tastes (such as a God who reads Leviathan rather than creates him), atheists would have no problem believing in him. However, in just a case, this God would be considered a peer of sorts; it's far too un-enlightened to worship something. If this God demanded worship, atheists would probably want to have a vote on it first. [Answer] Simple: It does not work if you are serious with your definition. What exactly happens is always dependent what "God" exactly is. A "god" in a coarse definition is always a being which is much more powerful than a human being. I am not talking about "outsiders" in the folklore like elves, demons etc. which may have superior abilities in one case but are severely limited in other cases. We are talking of something where the power balance is strictly in favor of the "God" being. So science with our limited knowledge and accessibility is *never ever* able to prove conclusive statements about a being which is much more powerful because this being would be always able to trick humans into believing things which are not true. Scientists are well aware of the limitations the human mind has. How would you "empirically" test something which has a much more deep insight into yourself and much more power available to bend the results in favor of their case ? So you never can "prove" that a being is omniscient or omnipotent. > > ADDITION: I forgot to mention that "proving" statements about > intelligent beings is already a real-world problem. In medicine and > sociology we have a severe reproducibility problem because those > damned humans are reacting so *different*. Use the same location, the > same time, the same procedure and the same experimenters; if the only > difference is another group you can still get vastly different results > ! It only gets worse if other variables are changing, too. The whole > area of meta-analysis was pushed forward to cope with these problems. > > > So what really counts is how the "God" is interacting with the reality and the human world. The easiest way is if we have Epicurean/Deist/Transcendental God(s) which do not interact, do not want to interact with us or our reality or make it in a way we do not recognize. Then there is no difference between existence or non-existence because science has only access to our reality. If the Gods *do* interact with our reality, we have several cases: a) They are showing adaption. They are punishing disrespect or rewarding loyalty, depending on cases and show some kind of intelligence. In that case non-believers would die out quickly or be converted even before the scientific method were invented. The speed of dying out would depend on how harsh or how regular they dish out, but even small differences would lead invariably to the demise of the non-believing population. People would fear and revere that God(s). b) No variation. In that case it is likely that people would encode the results as new "natural laws" and perhaps even do not acknowledge a God. c) Chaotic interaction. They interact with our world, but for no discernible (for us) reason. Depending on how many times they interact, the people would be likely either accept freak accidents or have constant paranoia. In all cases I do not see that law and government are necessary to do anything because the God(s) would act on their own accord and do not need mortal help. In fact blasphemy laws are a sign that we either have no gods or that the God(s) are Epicurean, deistic or transcendental (pantheist/panentheist) gods. [Answer] In a world where some God is empirically shown to exist, there will continue to be atheists. The atheists will claim that something has been empirically shown to exist, but: * it is not God; it is some extra-terrestrial creature which has duped humanity into believing that it is God, using its advanced powers to manipulate the physical world. That creature did not create the world, and is not unique either; it comes from some place inhabited by other such creatures. * the creature is not actually God of any particular human religion; it just bears a resemblance, evidenced by various otherwise incompatible religions all claiming that it is their God. * feats of omnipotence can be faked by manipulating the human mind. For instance, a sufficiently powerful extra-terrestrial may have the technology to implant, directly into a human's brain, the false memory which causes the human to believe that he or she just witnessed a miracle, when no such thing happened at all. By such means, the extra-terrestrial can fool humanity into believing that it has powers which it does not have. Therefore, the empirical researchers have been fooled. Their data is fake, and their experiences are false memories. Others people will reject these arguments and choose to believe, creating conflict between those who want to save humanity from the evil extra-terrestrials, and those who want to be united with their God. [Answer] **Nothing new** You set up a system which is very close to inconsistent, and when you do that, the microscopic details get magnified to importance. Science's definition of "proof" is a statistical one. "The evidence we have seen so far is statistically consistent with scientific model of 'God.'" Now, consider that you have faith in religion A. Science claims they have a 99.9999% confidence in the God of religion B (I chose 6 nines because that is roughly what scientists consider "proof" of a subatomic particle). Given that you have faith religion A is true, and there is a 0.0001% chance that statistics lead science awry, you will merely assume this rare chance happened and go about your business. Remember, religions talk about immortality. Would you really risk your immortal soul and disbelieve the religion you have faith in, just because science said so from a finite amount of evidence? Over time you would see political changes. That religion's view on birth control would soon become law, for instance. This is nothing we don't deal with today (we just don't have a scientifically "proven" answer). [Answer] > > Sadly, I cannot think of a scenario how this could be proven, but that's the point of Worldbuilding.SE right? > > > The God appears in person and does things like change the gravitational constant of the universe by a pre-determined amount for 24 hours. Or makes the Earth a satellite of Jupiter for a day before moving it back. > > How would believers of other religions react to this? Would monotheistic religions be abolished if the proven god isn't theirs? > > > The major religions all go for the same God. They differ on the prophets they use as a conduit to that God. You've mainly got the carpenter, the merchant, and the wandering mendicant; the Jews seem to have a direct line. Unless God specifically denounces one of these prophets it will likely be business as usual. If God *does* smite one of the major prophets as a fraud you will see catastrophic social chaos in regions where that religion is dominant, rearrangement of social and legal processes (and national holidays) where that religion is a substantial part of the background (think christianity in Europe) and a lot of snickering everywhere else. > > How about atheists? > > > With irrefutable proof that a god-like being exists the atheists will accept the existence. But unless there is an irrefutable commandment to assume the position for ten minutes every other Thursday the atheists will likely continue as usual. [Answer] So far as society is concerned, I don't think it really matters whether it's scientifically proven or not. What matters is whether people believe it and act accordingly. "Scientifically proven" means, more or less, that "scientists" believe it and act accordingly because of some experimental evidence that supports a particular hypothesis by refuting contradicting hypotheses. So, either your hypothetical scientific proof is sufficient to convince everyone else to take up the proven religion, or it is not. If the hypothetical scientific proof is *not* sufficient to convince non-scientists (at least, those not of the religion whose God is proved to exist), then you might have a situation a bit like popular belief in quantum mechanics or that smoking causes cancer. People on the whole believe it, kind of, because they mostly believe scientists tell the truth most of the time. But any given person might not understand it, might not act on their belief, or might refuse to believe it if that's inconvenient for them even though it's "scientifically proven". It could affect public policy (to the extent science ever does, i.e. to the extent it's convenient for politicians to believe scientists) without affecting every single person. If it is enough to convince the layman, then everyone would believe in God. There might not be many historical societies we can look at where that was *strictly* true, but we certainly know of societies in which nearly all people broadly-speaking belong to the same religion, and where multiple religions exist but atheism is very rare. So the question is solved in the abstract: you'd have a society in which everyone sincerely believes in God, and that would be open to all the variety consistent with that. Assuming no earth-shaking changes *other* than the common belief God exists, religions contain a lot of statements about the nature of God. It can be difficult in some religions even to get two randomly-selected co-religionists to agree a statement of belief, let alone between religions. So, depending on the nature of the proof there might be a lot for religions to disagree on, principally the *practical consequences* of the existence of God for morality, worship, and so on. So perhaps people could on the whole retain their religions, present-day atheists could reason that although it turns out God exists, that has no consequence for them, and so on. So, just because God exists doesn't necessarily mean he rewards virtue, punishes evil, or that there's an afterlife, or that he wants people to be kind to animals, or anything else someone might advocate in the name of God. People of different religions can easily believe that God exists and carry on disagreeing about everything else. See for example the Protestant Reformation: the dispute was not over the existence of an omnipotent, omniscient God. Perhaps not quite *everyone* was agreed there was one, but I don't see things going down substantially differently if it had been literally everyone. However, if the nature of the proof is, for example, "Christianity is proved correct because Judgement Day occurs", then of course Revelation has a lot to say about what happens around that event, which we could say is substantially correct in your world. Then we can say that society would be radically different from any that's gone before, on account of Heaven being manifest and whatnot. If the world doesn't end but one religion is proved correct *in general*, not just specifically in its statement that God exists, then what would follow would be a society in which everyone sincerely believes that particular religion. The nature of that society depends very much on the nature and strictures of the religion you choose. And have we proved "the religion as a whole" correct, or have we proved that a particular sect or denomination is correct? The Roman Catholic society is different from the Methodist one, do we have to choose one or do we keep both? Basically, to prove "the Christian God" exists, you have to decide which of the properties ascribed to God by various Christians at various times, are actually possessed by (and proved of) the God who has been proved to exist. The actual transition might be very complex and unruly. It's not necessary that everyone would just convert to (for example) Islam overnight. AFAIK it's possible to convert overnight, but people would have to take their time beforehand to process the proof and be convinced by it, and afterwards to learn how to live as a Muslim. Regardless of the practicalities of transition, if the case is presented convincingly that everyone should be a Muslim then the trend would be towards a Muslim society. Other religions take different views on conversion. For example, I think (someone please correct me if I'm wrong) that I could believe Judaism to be true without necessarily concluding that I should become a Jew. Naturally you'd have to carefully research the specific religion that you decide to make true in your fiction, or you'll have an offensive pastiche at best ;-) Finally, I note that there's a great deal of speculative fiction in which the existence of some kind of supernatural goings-on *could* be scientifically proven, except that it's rare and there's a conspiracy to keep it secret, and ironic or farcical plot elements combine to prevent the proof being documented, and so on. If the scientific proof of God was of this kind: "there are actual *angels* running around, and they've met God, so there's your proof" -- "well, I haven't met any angels yet, so I don't believe it yet", then you have plenty of fictional precedent for what might happen. Hi-jinks, basically. [Answer] I must first argue it's virtually impossible to prove a single religion's god as the real one, because the best religions are the ones that make God subjective. He's in all of us, and he defies understanding. Sound familiar? Yeah, because it's designed to appeal to everyone, and give no real explanation of what God is really like, so that everyone in your congregation can believe in a different God and still get along. God, if He does not exist, is an imaginary friend, and thus we apply to him many different characteristics that aren't in any holy book. Try wrapping all that up in one being and no one will be able to tell you what religion it came from. That said, imagine you've proven that God exists, without tying Him to a single religion. Here's a simple example: Some guy had an idea of what God was, and he founded Judaism. By the time Yeshua came around in the first century, there were possibly dozens of versions of the Jewish God. Then, in the centuries after Yeshua's death, dozens more Jews started formulating new versions of God. This led to Christianity. Now we have dozens more versions of the Christian God, and probably just as many versions of the Jewish God. Add in Islam if you want. The point is, this all stemmed from one guy's idea, and he probably said a lot more than "God exists". Now, imagine an experiment is conducted. Perhaps there's a proof, and the result of this proof is that God must exist. At this point, you're no closer to 'knowing' God than any religious person; you've just both agreed on an axiom. As other answerers have said, and as I hopefully have shown, this existence proof probably won't go against most major religions; the real change comes from the non-believers. The most likely outcome I can think of is that a new branch of science will spring up, aimed at figuring out which parts of which religions actually are correct. A similar example would be how no one put any thought to the Trojan War until they uncovered the city of Troy: now that they have evidence that some part of the story is true, they want to know how much of it is true. In your case, learning about God and His plans for us will be of the utmost importance. However, just like how most religious people aren't actually that committed to uncovering the hidden mysteries of God, most ordinary people probably won't put too much thought into these scientific endeavors. If anything, it'll be like finding the 'God particle' or toast that looks like Jesus: most religious people will think it means they're right and go on doing the same thing as before, while most non-religious people will think the aforementioned religious people are ignorant and dangerous, and do as much as they can to strip down all the false facts religions have been spewing out for so long. There will probably be a new branch of athiests, but they'll be virtually indistinguishable from modern ones, vehemently denying any suggestion of a god regardless of the lack of proof. Nothing new there, just goes to show that a system of beliefs is only slightly affected by the realm of fact. [Answer] Well... let's take a look at THGTTG. There's usually something in there. Of the Babel fish: > > Now, it is such a bizarrely improbable coincidence that anything so mind-bogglingly useful could have evolved purely by chance that some have chosen to see it as the final proof of the *non*-existence of God. The argument goes something like this: > > > "I refuse to prove that I exist," says God, "for **proof denies faith**, and **without faith I am nothing**." > > > "But," says Man, "the Babel fish is a dead giveaway, isn't it? It could not have evolved by chance. It proves that You exist, and so therefore, by Your own arguments, You don't. QED" > > > "Oh dear," says God, "I hadn't thought of that," and promptly vanishes in a puff of logic. > > > "Oh, that was easy," says Man, and for an encore goes on to prove that black is white and gets himself killed on the next zebra crossing. > > > Emphasis mine. People would pick holes in the proof. Both atheists and believers of other religions would nitpick and find holes that - while not THGTTG-style excessive - still "prove" that the proof is wrong. The "proof denies faith" argument is a fairly strong one: if someone claims to have proved the existence of a god, someone else can claim that the basis of their proof was something put into the universe by the *real* God to see how humans would react to it. There are other people who are just plain stubborn and will point-blank refuse to believe that the new proof is valid. This has happened with many other important scientific discoveries: perhaps most relevant is the discovery that the Earth revolves around the Sun not the other way round. The discoverer of this theory was placed under house arrest due to the Church's demand for heresy; they didn't like how his idea went against what they'd thought for centuries. [Answer] If the god were in favor of a standard of behavior that most people disliked, the people would probably figure out a way to hide the evidence and/or rationalize it away. If the god didn't intrude and let people choose their own path, the scientific evidence for the god's existence would eventually be very hard to discover. Those who did discover it, even if it were obvious, would probably be branded as social outcasts, either crazy, immoral, or criminals. However, since the evidence is scientific, it would be undeniable and those seeking to quiet the truth seekers would resort to ad hominem and strawman attacks, and look for ways to discredit their message and keep them from expressing it. Finally, those who did not like the truth about the god's existence would probably end up killing the really persistent truth seekers. [Answer] **Could other gods be proven this way?** It's not hard to imagine that a proven religion would quickly establish supremacy over other religions. But it's a safe bet that at least for a while after the initial proof is discovered, believers of other faiths would attempt to use the same process to prove their gods too. Even if the particular method of proving God also somehow proves that it's pointless to try it on other religions' gods, the remaining believers of those religions would still try, at least for a time. **What about quack theologists?** In the real world, it's not so uncommon to see bogus proofs of bad scientific theories, made either by cranks who honestly believe they're onto something or by charlatans who are trying to sell a product. The anti-vaccine movements are a timely example of this. In a world where God is proven, it's not hard to imagine theologians trying to get in on the game, with bogus proofs of their own gods (or bogus proofs of some particular aspect of God). **What would atheists think of this God?** True atheism would likely all but vanish in a world with a proven religion: not believing in the existence of a God whose existence has been proven would be insane. But this doesn't mean that dissatisfaction with religion would vanish. Even in the real world, there exist a few people who call themselves maltheists (or sometimes dystheists). They believe that the being called God exists, but that He is evil, fraudulent, or otherwise unworthy of worship. **In a world where a God is proven, maltheism could rise to the same kind of prominence that atheism has today**. They might even continue to call themselves atheists, after their nearest philosophical ancestors. Conversely, believers might start to use the term "atheist" as a slur against the maltheists. Another thing to remember is that **not all maltheists would come from atheist stock**. Although many similarities can be drawn between the moral codes of most real-world faiths, almost all of them share some very stark difference as well. Some maltheists could once have been believers of other faiths, who call God evil because He differs from their moral codes in some important way. [Answer] **Want to improve this post?** Provide detailed answers to this question, including citations and an explanation of why your answer is correct. Answers without enough detail may be edited or deleted. Many would be in utter denial, claiming this real god is really the devil there to trick them. Atheists would have to admit defeat if they wanted to continue to use science to back them. [Answer] For starters, I'd say it would depend a lot on the nature of the proof. As a Christian, I'd say that there is overwhelming evidence that Christianity is true if people were only willing to look at it with a fair mind. Of course, atheists are just as quick to say that there is overwhelming evidence that their beliefs are true and it's the Christians who are obstinately ignoring the facts. Etc. Every now and then an atheist will say something like, "If there really is a God, why doesn't he strike me with lightning right now for blaspheming him?" Suppose that at the very moment that an atheist said that, a bolt of lightning tore through the roof the building and hit him. Would all the atheists in the world then say, "Zounds, we were wrong! There really is a God!" I sincerely doubt it. More likely they would say, "Wow, what a bizarre coincidence!" I'm sure most would deny that any such thing ever happened. Even if you had video of it, I'm sure there would quickly be people coming forward with absolute proof that the video was faked. I'm not singling out atheists here. Lots of people come to their conclusions first and then look for evidence to support those conclusions, and any contradictory evidence is just ignored. (Lots of people who disagree with me, I mean. Obviously people who agree with me have all examined the evidence with absolute fairness and objectivity. That's why they agree with me. :-) So frankly, if there was some such proof -- like if someone actually made the Sun stand still or came back from the dead or something irrefutable like that -- I'm sure that many people would find a way to explain it away, from claiming that it was all a fraud or a hallucination to elaborate alternative explanations. Sure, some would be convinced. So I think you'd just end up with what goes on in the world today, but more so to whatever degree that this "proof" was hard to deny or refute. Some atheists would be convinced, others would not. Some people of other religions would convert. Some other religions would adapt their teaching to the new information. Etc. [Answer] I'm going to take a tack not taken by others here. This should be noted that it can *only* speak to a universe where there is only *one* "god", though the viability of multiple gods is somewhat in question (having multiple omnipotent and omniscient entities brings some logical contradictions, such as the fact that one could magic all the others out of existence at any time). --- What would happen if it were sufficiently proven that a supernatural, omnipotent, omniscient deity were proven to exist? **Rebellion!** Basically, this boils down to the problem of evil, and the fact that a *benevolent* deity (or pseudo-deity) possessing omnipotency and omniscientcy would functionally preclude the existence of evil. Omnipotency implies that the holder of said omnipotency can create a similar universe to the current one where suffering does not exist, with out any other negative side effects. The fact that this deity has omniscience means that it must therefore *know* it can fix the problem of evil, and **it chooses not to**. Therefore, definitive proof of an omnipotent and omniscient god is also proof that **that god *must* therefore be evil** (assuming evil exists in the universe). As such, the only sane reaction I can think of is either acceptance of the fact that all the sentient entities in the universe are functionally slaves, or rebellion. [Answer] The God would not just have to be "proven" once but would have to stay around here pretty long time, to be proven over and over again. And how do you actually prove something like that so that all scientists will agree to it and not eventually challenge the proof? A basic reason for this is that a lot of "science" is based on axioms that themselves are based on interpretations and assumptions. An example of this is related to the age of the earth (note: I am not a young earth creationist or anything like that). None of us humans who currently live on earth were around when earth first "came to be". Consequently we do not have any eye witnesses telling us how old earth is (or even, how life first exactly appeared on this planet). The age of the earth is based on assumptions made about the age of Universe and the age of the solar system. Another example is the dating of dinosaur fossils. The fossils themselves are typically not dated directly (due to multiple reasons) but are dated based on the strata they are found in. Again the age of the strata is based on assumptions made about the age of the earth and interpretations related to the local geology. Of course not everything in science is based this little on eyewitness evidence. After all, "science" includes many different disciplines, and some of them (such as medicine and parts of physics) have greatly contributed to the advancement of technology in our era. The "problem" is that this has given many other sciences the appearance of being similarly completely based on eye-witness evidence (instead of assumptions and interpretations). So now you have the following issues: 1. in many parts of science, events are interprets through a filter that contains the same assumptions and interpretations that have been used so far 2. if the events are not the right type for the filter, they are categorized as "outside of science" 3. in the end all humans are fully capable of believing into what they want to believe in (without even consciously acknowledging this to themselves) or have chosen to believe in. For an example, just check how many Germans accepted the Nazi leadership during WW2. Very few saw much of any problem with joining the military and then going to another country to kill civilians, for example. After all it was all for the motherland and life is easier if one does not ask too many questions. So in the end, even if you have some cosmic events and some God appearing, the fact is that once all that is over, our scientist would be fully capable of interpreting all of it as some natural blip in the evolution of cosmos coupled with mass psychosis. Or something like that. Also, take a look at the story of the nation of Israel, as described in the Bible. The book of Exodus tells us how God freed the Israelites from slavery through various events that showed his godship (both in general sense, and when contrasted with the powerless gods of the Egyptians). As a final step in protecting the Israelites, God saved them from the Pharaoh by opening a pathway through the Red Sea that doubled as a trap for the Pharaoh. After these events, God led the people to Mount Sinai. While Moses was up on that mountain, the Israelites wanted to have another God so they made themselves a golden calf and stated that they will have a celebration to worship that calf the next day. The thing here is that that calf was a statue that they themselves created right there and then (according to Exodus, Aaron asked the Isralites for the gold to make it). It was clearly not a god of any sort, but a lifeless creation made by a human. More importantly it had not even helped the Israelites in any kind of manner. So here we had a situation where they turned their back on a God who actually had helped them and rather wanted to worship one that had done nothing for them. This was also before they were given the law covenant, so the law covenant cannot be claimed to have been the reason for their behavior. More likely they wanted to be able to choose their own god simply because such a thing would have made their life more like what they wanted. Free sex, and stuff like that. Now someone might argue that if God showed himself, humans would believe in him. Clearly the Israelites showed that it does not work very well like that. Because in the end, humans tends to believe what they want to believe in. And that is what would eventually color the "scientific" interpretations and conclusions of humankind, once any "revelation" type event was over. [Answer] People would likely collectively go "Huh. Who saw that coming?" Then, likely you'd see most of humanity adhere to said religion. This is nothing new. Humans tend to clump together over all sorts of group gatherings. When Team X wins the super bowl, suddenly Team X gains a whole lot of new fans. I do agree with some of the others (as well as yourself) that this is an impossibility, however. Religion as we know it today is strictly un-provable. It's built in to the definition of what constitutes religion today. Even within the major religious movements, there is so much fractured history that there's no one real story of any particular god. That said, if you're looking for examples of what the existence of a real god might end up looking like, you can find those in a lot of the major religion's texts. The Bible, for example, is based on the assumption that God is real and does real things. UPDATE: After pondering this more and reading through the other answers (which are all interesting...even if I don't agree with them all) I think there's perhaps even a higher-level answer to this question: **It all depends on what particular god was proven to be real and that god's particular rules of the universe** Someone brought up [reincarnation](http://en.wikipedia.org/wiki/Reincarnation) and I think that's an excellent example of but one particular aspect of religion (the afterlife) that could have drastically different effects on society depending on which version 'proves' to be real. Are you reincarnated as an animal? Do you go to Heaven? Hell? Is heaven the greatest thing ever? All sorts of scenarios could stem from that: * maybe the afterlife is 'pretty good' in that for a good chunk of the planet's population, they decide death is the next logical step. That could be good (planet's population under control)? Or bad in that whenever life just gets too hard, people just kill themselves (endless cycle of depopulation)? * maybe it's a gamble. Heaven or Hell. Maybe then there's a sudden wave of empathy and sympathy and governments start shifting towards more socialist and communal models and everyone starts striving to better humanity. That could lead to an interesting 'utopia on earth' model (hmm...there's a story idea right there...) * maybe heaven is a non-stop orgy and all-you-can-eat buffet. Within the weekend humanity no longer exists. Win win for everything as humans are partying in Heaven and the Rhinos and Elephants back on earth can finally do as they please. * maybe it's "There is no afterlife, this is all you get" in which case maybe not a lot changes at all...some societies are OK with this now and live peacefully, some societies are everyone-for-themselves and that wouldn't change either. ]

[Question] [ I am posting this in behalf of a friend of mine from a distant world. Here is his message properly translated to English: > > Hi, Sol3αlings1. My name is $ѬӚᕕƨ⧬௵44ħ$. We are peacefully and we need your help. I am a scientist/engineer from the planet $⋒◥27⟑▓⍫⋒இǪ$. We calculated that our home star, already an instable red giant, will explode as a supernova in some years. > > > Our home planet is small, but we have very highly advanced technology at our hands. Our planet is orbiting our home star at an orbit that in its median is a mildly temperate orbit, not too close to be scorching nor too distant to freeze out the planet. Our star is very unstable, as all red giants are, and it may enlarge and shrink chaotically, which would occasionally toast or freeze our planet, but our technology is able to easily cope with that. Exactly, our planet is in a $38.6\text{ }⛮֍㐃$-wide orbit2. > > > Our problem is that we want that our home planet be able to survive the supernova explosion, but we can't figure out how, so we're sending this signal seeking for your help. We don't want to take refuge elsewhere or just flee, we just want to find a way that allows our planet's surface and atmosphere to survive as much as possible. Having a lump of devastated planetary core and vaporized mantle behind and declaring it as "survived" is not of any use to us. > > > Further, I am aware of your communication "[If the sun were to go supernova, how long would Earth have before it was consumed?](https://worldbuilding.stackexchange.com/q/18269/3002)" that makes clear that if we don't intervene, nothing of our planet will be left behind. Also, we know about "[Can a planet survive a supernova?](https://worldbuilding.stackexchange.com/q/19000/3002)", but it is not very useful to us, because that was directly to planets which could naturally survive the explosion while we will use our most advanced technologies instead. Also, we know from "[If the sun were to go supernova, how long would Earth have before it was consumed?](https://worldbuilding.stackexchange.com/q/18269/3002)" that if we don't intervene, nothing of our planet will be left behind. > > > We are also aware of "[How can we extinguish a supernova?](https://worldbuilding.stackexchange.com/q/16780/3002)", but we don't want to either prevent or stop the supernova, but for some... huh... well... RELIGION (yes that is it) reasons that huh... well... our deity asked to us (haha), we now understand that the star needs to reach its natural destiny, but our planet should remain as our lively peace of rock, even if it ends being a very cold one. > > > So, **how could we make our planet survive afterall?** > > > You may think that it is strange that we ask you for that instead of finding the answer ourselves, since we are a very advanced technological civilization. But there is a very simple answer for that. It is easily explainable due to $⍬ईШ3877]֍$ > > > > ``` > error - signal lost > error - data truncated > error - data consistency check failed > error - syntatic token limit out of bounds > fatal - unexpected failure 15894 > Please go to http://digital-alien-transceiver.com/bugdatabase/ > and file a bug report after checking for duplicates. > Don't forget to inform your transceiver configuration parameters. > Thank you for your collaboration. > info - signal recovered, data reception will be resumed > > ``` > > $Ш568ԖѼ⋒45993⋒ᐉ$ be thick enough, or maybe not completelly, otherwise it won't work. Very simple, isn't it? > > > I greatly appreciate your help. We are very sure of your peacefully collaboration. > > > Also, I got this other transmission from my space friend talking to one of his other friends. Looks like some sort of random gossip: > > Are you an idiot? I order you to stop right now if you don't want to be executed for insubordination and stupidity. We need to keep our datacenter nearby that *freaking*3 star when it explodes [to collect as much energy possible in order to decrypt the data](https://security.stackexchange.com/a/25392/17080), not to take it far away. > > > The only thing that we are still lacking is to find a way to not vaporize our orbiting datacenter-planet before we proccess all the data, and I already told you stop insisting in that moronic idea of "just running away". We're not robotizing an entire planet to just send it to somewhere else, running away like a bunch of $ѦܮḺஹआ$4! That wouldn't make any sense! That won't decrypt the message! So, please, please, keep the focus in your task which as I already told you like $2,985,984$ times is just to preserve the datacenter intact during the explosion until we decrypt that *freaking*3 message. > > > Now go back to your actual work, because it is only your department that is behind the schedule, otherwise you will know what is feeling real pain. Even the guys from the stellar Dyson-sphere could figure out how to collect and store the explosion energy, but you on the other hand, seems to be a complete incompetent! > > > *End of secret transmission. Disclosing or leaking the content of this transmission is a crime punishable with a cruel death.* > > > So, that is it: **How could we make a planet survive a supernova explosion without it being vaporized or even significantly eroded?** There is a very advanced alien civilization working and spending resources on that. 1: A Sol3αling is an inhabitant of some planet called "*Sol-3α*", i.e. the α-body in the third orbit around some star called "*Sol*". Could you guess which planet is that? 2: Sorry, I lost my table for converting that distance to Earth-like measurement units, so I don't know exactly how much is $38.6\text{ }⛮֍㐃$. Maybe you could provide the numbers that seems to work best while I search for the table and do the conversion so we don't lose any time? 3: Unsure of the translation of this term. Maybe there is another suitable word starting with the letter "f"? 4: This is some sort of animal-like creature that fears everything and instinctively run away from anything that remotely could pose any danger. A somewhat near translation to English in the sense it was used in the context would be to "*running away like a bunch of coward chickens*". BTW, I found out that $2,985,984 = 12^6$. Maybe they count using base 12? --- Notes for answerers and dupe-closers: * The aliens may engineer/build anything that they want that do not violate the laws of physics. * In fact they do not need to preserve living beings in the planet. It is just a robotized planet. I.e, a piece of rock that was converted to a giant planet-sized datacenter. Whatever is its atmosphere or surface composition, it is very different than something that would be created by nature. However, whatever is the data-processing hardware that they use in the planet, it must survive the explosion. * Running away, i.e. just moving the planet to somewhere very far from the supernova, do not solves the problem. The aliens need to keep the planet around the supernova. In fact, they are interested in this planet exactly because the star will explode as a supernova. --- **Note for everybody**: I had a lot of answers (21 non-deleted so far), so it was a hard time to nail down the very best. No answer was perfect. All of them either misses something, contains flaws, are incomplete, overly simplify something, break or abuse the rules, presume some sort of doubtful at best speculative physics, contains some sort of gap or something left vague and unexplained, etc. None of them would give a definitive solid answer if this question had the tag [hard-science](/questions/tagged/hard-science "show questions tagged 'hard-science'"). Intuition says that it is impossible in [hard-science](/questions/tagged/hard-science "show questions tagged 'hard-science'"), but being able to prove that there is simply no way ever to manipulate space-time, dark-matter, or whatever else for that (or prove instead that this is indeed possible somehow) is probably way beyond our present-day knowledge level in physics. However, since this question do not have that tag, this is ok. Anyway, the answers which I consider somewhat acceptable are from [Thucydides](https://worldbuilding.stackexchange.com/a/47466/3002), [John Dallman](https://worldbuilding.stackexchange.com/a/47537/3002), [Jim2B](https://worldbuilding.stackexchange.com/a/47464/3002), [Bob Gray](https://worldbuilding.stackexchange.com/a/47544/3002), [Physicist137](https://worldbuilding.stackexchange.com/a/47683/3002), [a4android's longer answer](https://worldbuilding.stackexchange.com/a/47566/3002) and [my own non-wiki answer](https://worldbuilding.stackexchange.com/a/47630/3002). All of the non-deleted answers posted so far provide some sort of valuable information and insight, even those that are flawed, incomplete or missing the point in some way. Further, almost all of the comments in the question and in most of the answers were very helpful also. Finally, after a lot of thinking and reasoning with myself, I considered Bob Gray's answer the best (by a tiny margin over the others), so I accepted his answer. Probably, many people will disagree and I am also very unsure myself because I had too many good and very different answers without any of them being perfect or clearly the best. Finally, I will still evaluate eventual further answers. [Answer] All you'd need is an Einstein-Rosen bridge situated so that it was placed perpendicular to the planet. Make the entrance, say, 2 planetary diameters wide and just let it sit there. The energy from the supernova that would have impacted the planet will instead go into the wormhole and come out wherever. I say place the other end near another supernova and hit one supernova with the other. Interesting! The huge width of the bridge would stop any "bleed-around" energy from leaking through and hitting your planet. Sit back and watch the show! [Answer] Since at the moment of core collapse and implosion a Type Two Supernova can outshine an entire galaxy of 100,000,000 stars, you have a pretty tough job ahead of you. The obligatory [XKCD comic](https://what-if.xkcd.com/73/) gives you a taste of what you are in for, holding a thermonuclear device *to your eye* would have *nine orders of magnitude* less radiant energy than a Supernova exploding at the distance of our Sun from you. With that sort of energy output, even using super science to put a Jupiter sized planet between you and the incipient Supernova isn't going to do much good; the cremated remains of the "shield planet" will strike your planet as a hypersonic cloud of plasma (the size of Jupiter) moments before the shockwave arrived to sweep away the mess. [](https://i.stack.imgur.com/kYsHy.jpg) This [article](http://www.space.com/22446-supernova-shockwave-speed.html) suggests that the shockwave is coming at you at *8 miles per second*. That is relatively slow compared to the monster outpouring of energetic radiation that has already swept through your world at the speed of light after the core implosion, but it will do a fine job of pushing the plasma left behind by your planet out of the Supernova's remnant space. I suppose that some sort of metamaterial could be devised to refract the energy of the supernova around your planet, but the issue here is the amount of energy is so extreme that even absorbing the most miniscule fraction of the energy will damage the device, and once parts of it start to melt/vapourize, the rest will rapidly follow, and your planet for a fraction of a second thereafter. [](https://i.stack.imgur.com/9HI2m.png) The other issue is that metamaterials are optimized for particular frequencies, whereas the Supernova will be emitting energy over a very broad spectrum of frequencies, from long radio waves to intensely energetic gamma radiation. You can expect the same sort of thing to happen if you try to erect a massive mirror between you and the Supernova. Even a dielectric mirror reflecting 99.99999% of the light will rapidly vaporize and of course the mirror is not going to be reflective in all wavelengths either. No, the only real way to save your planet when the core destabilizes and collapses, triggering the Supernova, is to *not be there*. Use your super science to create a wormhole and put your planet through it to another Solar System with a stable, quiet star, or use some sort of space warping geometry like an Alcubierre drive to get your planet out of the way post haste. If you had come to me with the problem a few million years earlier, there is the possibility of stellar engineering to prevent the Supernova happening in the first place. The massive gravitational pressure of the star is compressing the core and burning through the hydrogen at a furious rate. since much of the hydrogen has been consumed and converted into Helium, the gravitational pressure of the star is allowing Helium fusion to take place, and moving up the curve of binding energy to heavier and heavier elements. When the fusion reactions create Iron (Fe) the process stops, since Iron creates no net energy when fusing (or fissioning, for that matter), so the gravity of the star is no longer opposed by the energetic output of the fusion reaction at the core: the star implodes creating the Supernova. Using a technology called "[Star Lifting](https://en.wikipedia.org/wiki/Star_lifting)", a great deal of matter could have been "lifted" from the outer layers of the star, reducing its mass and placing it lower on the Hertzsprung–Russell diagram. The extra mass could be stored in a series of artificial gas giant planets and used to fuel the star in the far distant future, or to do other things in the here and now. Based on the description, the star is already close to collapse, and I'm not entirely sure what would happen if large amounts of mass were suddenly removed from an unstable star. I'm not really willing to try that experiment, are you? [](https://i.stack.imgur.com/729KV.png) *Using artificial magnetic fields to pump solar plasma from the stellar poles* [Answer] This isn't a supernova problem. This is a pointy-haired boss problem. It gets much easier once you realise that. "We are going to have to move the planet a bit, but that will minimise depreciation on the hardware." We're going to move it further from the star, but we are going to keep it in orbit around the star, so we are *not* running away. Since it's at least eight times the mass of the Sun, we can stand a *long* way back - at least three light years - and still be in orbit. Call it 200,000AU, which means the damage from the supernova will be reduced by a factor of 40 billion, as compared with being in an orbit like Earth's. At this point the damage is about a fourtieth of having an H-bomb go off next to you. That means you can build a shield for your planet out of all the other planets in the solar system, and potentially have it actually work. [Answer] Create a pocket dimension and move your planet in there. During the nova, make the entry to the pocket dimension (that is, the size of it as seen on the outside) small enough that the energy that enters is no larger than the planet can handle. After the nova, you can widen the entry again and get your planet back into normal space. [Answer] ### A question of scale Supernova are powerful, extremely powerful. Imagine the most powerful explosion possible. Supernova are more powerful than that. [Xkcd has this important note about how powerful supernova really are](https://what-if.xkcd.com/73/): > > However big you think supernovae are, they're bigger than that. > > > Here's a question to give you a sense of scale: > > > Which of the following would be brighter, in terms of the amount of > energy delivered to your retina: > > > 1. A supernova, seen from as far away as the Sun is from the Earth, or > 2. The detonation of a hydrogen bomb pressed against your eyeball? > > > A: the supernova by $1 \cdot 10^9$ times! ### Can planets even survive? Earlier a question was asked on this board: [Can planets survive a supernova explosion?](https://worldbuilding.stackexchange.com/questions/19000/can-a-planet-survive-a-supernova). I recommend reading the answers. In summary, if a planet is sufficiently far away, then some planets could survive. For instance, if you placed Jupiter in orbit around a star about to go supernova (Type II), then there is a very good chance Jupiter would survive. At Earth's distance, the Earth would not (then again, Jupiter probably wouldn't either). There's only been a four planets found around pulsars (supernova remnants). Of those, we think that only one was present before the supernova. However, [this "planet" started as a star](https://en.wikipedia.org/wiki/PSR_J1719-1438). The "planet" that is left is the star's carbon core. The supernova blew the rest of the star away. ### But could people survive? Let's assume the planet is far enough from the supernova to prevent its vaporization and placed behind some other object (like another star) to protect its fragile surface from being blasted into space. Even then you need to worry about a lethal dose of neutrinos. The XKCD link above states that you need to be a minimum of 2.3 AU away from the supernova or the neutrinos will kill you regardless of the number of stars you use as a shield. In fact, you'll want to be significantly further away than 2.3 AU or large fractions of the population will die from the neutrino flux. ### Yes, you can save the people But you'll need to: 1. Move the planet as far from the star as possible. Probably 5 or more AU away and further is better. 2. Place another object between the supernova and the planet to shield the planet from the normal radiation blast. A big planet is a minimum, a big star would be much better. 3. There are still no guarantees. [Answer] It seems your aliens have got 2 contradictory problems: a) they want to maximize energy extraction from the supernova, b) their equipment can't withstand a supernova. Short answer: shoot the management, evacuate, come back when they have a clue [Answer] The interconnected sea of Higgs Bosons constituting space time has some properties of non-Newtonian fluids. Normally, the linked bosons provide the "medium" which propagates interactions between different points in space time with the speed of c. But excited by a specific resonance frequency of gravitational vibration, the bosons stop interacting conventionally. Space time starts to resemble a friction-less super fluid. Interaction between different tempo-spatial locations are near-"instantaneous". A plane of such an anomal "super-fluid" space time would act like a shield from events like supernovae on the other side of it. Leakage from the plane is minimal; all events are propagated with high preference *inside* that plane, much like electrical charges travel inside a conductor. The effect can be visualized as a spatial-temporal Faraday cage. Conveniently, the events (and the energy they carry) leak at the edges of the plane where they can be harvested, for example to carry out computations. The details are rather tricky: Close to the plane's edge time and space do funny things (let me say that the tidal forces are your least worry), so that you want to keep a healthy distance. The plane must be large to shield the planet effectively; the energy pouring out at the edges partly radiates inwards, and it's a *lot*. Creating a super fluid Higgs Boson field of that scale requires a large amount of gravity resonators placed at very precise locations in order to create the required wave form. It also requires an inordinate amount of energy which would plainly not be available under normal circumstances. Luckily, the supernova will provide plenty, which can be used to bootstrap the field at the moment when it is needed. The engineering problems are enormous, but they are just engineering problems; I'm sure you'll solve them in time. [Answer] My dear friends, worry not! Your planet will be safe, your religious rituals will be fulfilled, and you will be able to collect plenty of data should you chose to do so on a whim ;) You must construct a massive object, known to us as a black hole (even better would be a charged black hole). Use the fundamental forces of nature, gravity and electromagnetism, to maneuver this black hole precisely between your sacred planet and the star. Use thrusters to maintain your planet at some distance from the event horizon, while still being in the umbra of the black hole. You may worry that this will obstruct any data coming from the star, but you are mistaken. Gravitational lensing will ensure some of the radiation coming from the explosion will reach your receptors. The further away you are from the event horizon, the more of this data you will receive. You can fine tune your position so that you get as much data as possible without being annihilated. If you are worried about the gravitational effect of the back hole interfering with the supernova itself, you can always move your planet and black hole back a little but (not run away, but maybe a couple more AU's) [Answer] "The aliens need to keep the planet around the supernova. In fact, they are interested in this planet exactly because the star will explode as a supernova." This suggests that if the aliens want to keep their planet in orbit around a supernova they must have (a) a good reason for doing so, and (b) some way of using this to their own advantage. What (b) suggests is that the aliens already possess the technological means to save their planet. This message is just a test to see how smart we are. Basically it's a trick question. To determine if we can work out that they don't need our answer to save their planet. OK, aliens if you can do it, then just do it and stop pestering us poor Solar3alings for no good reason. [Answer] There is a very simple solution, and won't require that much energy (in comparison with some of the answers). Warp the spacetime continuum (like [alcubierre](https://en.wikipedia.org/wiki/Alcubierre_drive)) somewhere in between the star and the planet, in such way to divert all radiation/neutrinos/plasma/garbage/etc away from the planet. (And away from the warp-machines, of course). So... basically a big gravitational lens/shield. [Answer] Supernovas are *unimaginably* violent and energetic. So far as we know, **no** planet can realistically survive one. Meh, no planet in a goldillock zone can even survive a red giant star-phase. To do an impossible task, you must also possess impossible impossible power and skill. So then, with far, far futuristic technology, you have these options. # Method 1 One method to *survive the supernova* is to not let a supernova occur at all. You can: 1- use an immensely massive rocket engine to push your planet away from the parent star. Then bring in a small white dwarf to the parent star so that they are as close to each other as possible, without colliding into each other. The white dwarf, being superdense, would have far stronger force of gravity than the parent star, and would suck in material from the parent star. However, if white dwarfs suck in too much material, they can *themselves* explode in a supernova. So when the said white dwarf has sucked in just enough material, move it away from the parent star and bring in another white dwarf. With a few dozen such *visits* you can remove the mass of the parent star enough to avoid any risk of supernova at all. Now use the immensely massive rocket engine again to bring your planet closer to the parent star. 2- explode away huge chunks of your parent star using anti-matter *bombs*. Basically you want to fling anti-matter packets at the parent star. Once they hit the star, they would annihilate to create millions of hydrogen bombs sized explosions (matter and antimatter annihilate on contact and result in an Einsteinian explosion of $E = MC^2$). Explosions of this scale occur all the time in the core of a star, but are suppressed by the monstrous gravity of the star. On the surface, there would be nothing to contain or suppress them and ***huge*** chunks (upto the mass of half an Earth or so) of the star are torn away with each such event. Make sure to cause these gargantuan explosions to the ***other*** side of the star from your planet (the side facing away from your planet) so that your planet doesn't get swept clean by the ejecta. Once you have successfully blown away enough mass of the star, you have circumvented the danger of the supernova altogether. # Method 2 Move your planet faaaar away (at least a light year away) from the parent star. You would have to subsist on your own generated power on the planet as no stellar energy would be available. But with your exaggerated level of technology, this should be easily obtainable. Once the star has exploded and the debris settled, move your planet back to where it used to be. [Answer] Can you create an artificial black hole? Take one of your planets and collapse it into a singularity, and then launch it into the center of your sun? My limited understanding of supernova is that the outward explosion is a result of an inward collapse as fusion comes to an end, thus initiating a much more rapid fusion which counteracts the collapse, and sends everything flying back outwards. I don't know the math to do such calculations, so I don't know the net result. I see multiple possibilities: 1. The inner mass gets sucked into the black hole. The fusion gradually peters out as it loses density. It causes a gradual collapse of the outer star, eventually sucking the whole star in, but the energy released from the accretion disk is absorbed by the surrounding hydrogen. This is the effect you are searching for. 2. The mass gets sucked in so fast, it terminates the star's fusion, the whole thing collapses inward, but the black hole's force isn't enough to collapse the outer layer before a rebounding shockwave in the middle regions (between the black hole and the remainging outer shell) triggers the supernova prematurely. 3. The black hole just sucks in everything in as it gets close, and the release of energy blasts apart the system more intensely than the supernova itself. Maybe other possibilities I haven't thought of. Anyway, I suspect that the exact effect is going to be determined by how large the black hole is, how fast it is moving relative to your sun, exactly where it hits and the angle of incidence, and who knows what else. If you consider this an option, I strongly recommend you run as many simulations as you can, if you do it wrong, you're liable to make things worse. Another option with a black hole would be to make it graze the outside of the sun rather than entering into it. If you can put it in a close but stable orbit, maybe it could extract mass gradually enough that it won't trigger a supernova, and might even leave a small star behind at the end. Again, run a lot of simulations of this scenario before attempting it, don't just guess. There's so many things that can go wrong. It's still going to be releasing unimaginable amounts of energy as matter gets pulled in, but hopefully you can end up directing a good chunk of it inward to the black hole instead of in your direction, and hopefully it will be a lot more gradual than a supernova. [When I say "you should run a simulation", I'm talking about the aliens in this situation, who should obviously have the computing power to do so.] [Answer] This is a community wiki "non-answer" to summarize answers that won't work, at least not without some severe modifications. Feel free to edit this if you wish. 1. **Move the planet to somewhere else very far away**: This qualify as "*just running away*" which the OP specifically tried to reject right from the start because it is the easy non-interesting obvious solution. Coming back later does not makes this any better. Replacing "*somewhere far away*" with "*inside a hidden dimension*" or something like that do not makes it really different. 2. **Preventing the supernova from happening**: Also something that the OP specifically rejected right from the start because it makes the challenge uninteresting. Making a black-hole swallow the giant star prior to its explosion would not also make it any better either. 3. **Use magic, unrestricted time-travel as in *Back to the Future* movie, faster-than-light communication, TARDIS, unobtainium adamantium shielding, [technobabble](https://en.wikipedia.org/wiki/Technobabble), etc**: If you are inventing your own physics, then every answer would be possible, making the challenge uninteresting and closeable as too-broad. So, this is not valid. 4. **Putting a massive planet or a smaller star as a shield**: It would work to shield the planet from the initial blast (except for neutrinos). However, as the supernova quickly erode the shielding object, its debris would obliterate the planet. Anyway, this could be workable with some modifications. 5. **Putting a neutron star or a black-hole as a shield**: Black-holes and neutron stars are tiny (measuring a black-hole size by its event horizon radius). They features only several kilometers in diameter, so they are too small to shield the planet. Further, their gravitational lensing would focus a lot of radiation from the supernova on the planet. However, some modifications to this setting might make this workable. 6. **Using a very large black-hole**: If you get a very large black-hole to shield the planet, it would probably be at least an intermediate mass black-hole or a supermassive one, and it would very likely promptly swallow the giant star preventing the supernova or perhaps spaghetifying it to the degree that it becames an accretion disc. Again, some creative modifications to this setting might be workable. [Answer] Hmmm, here's an interesting thought: Create a station in-between the planet and star with enough motive power to maintain position against the nova shockwave. Any potential motive output will need to be offset so that it does not interfere with the planet. It will need shielding to protect it's functioning parts from not only the shockwave, but also the energy output, and any stray chunks of stellar crust or core that may happen its way. It may also need something with enough mass to stop or deflect heavy particles which tend to ignore most objects with mass. It might need to be big enough to physically shield the planet from the nova. The primary function of this station is to generate, store, and emit massive amounts of anti-matter of various types. it will create a fountain of anti-matter, centered by a high pressure "spear" of anti-particles. Impacting the material of the nova will create continuous large explosions which will have the effect of parting the wave of the nova just in the vicinity of the planet. Remember to allow for the angular momentum of the planet's orbit, unless it is planned to temporarily halt the planet. Addendum: the motive source of the station needs to be powerful enough to not only withstand the pressure of the various waves a nova will generate, but also the long term emission of anti-matter, and the subsequent motion imparted by the matter/anti-matter reactions over time and remain functionally operative over time. It is possible to generate anti-matter now, and even store it for short amounts of time with our existing technology. An advanced tech-base should be able to do much more with the concept. Don't point the station at anything you want to keep, and don't let just anyone have the keys. Ever given any thought to ah, just picking an example at *random* mind you, building a dyson sphere around the sun at a distance likely to survive the output and then to just relocate the planet only far enough to put it just outside the dyson sphere and then hooking it into the power and sensor net of the sphere? Great way to store up extra energy, plus to avoid having your neighbors laugh at you for losing your sun, you could even have the sphere emit in the exact same spectrum as the pre-nova sun for quite a while. Just wondering. Oh, and according to some of our greatest thinkers on our planet, the answer is 42. Just in case you hadn't found that out yet. [Answer] I've done my funny answer now it's time to roll up my sleeves and get serious. Fortunately, everything needed can be found in the answers of my esteemed colleagues. Starting with Bob Gray's Einstein-Rosen bridge, but to start with it won't be inflated to its full size of two planetary diameters as that will come later. An Einstein-Rosen bridge was the first version of what we today call a wormhole. The original Einstein-Rosen bridge will be traded in for an Ellis-Bronnikov wormhole (also known as Ellis wormhole for short) with Gauss-Bonnet gravity conditions. Because no exotic matter is needed to keep it open. All the details about this type of wormhole can be found under this [rock](https://en.wikipedia.org/wiki/Wormhole). Youstay Igo's immensely massive rocket engine will be fitted into a high-acceleration long-range interstellar spacecraft. This vessel will transport one mouth of the Ellis wormhole. It is launched with an acceleration of one thousand gravities. If an immensely massive rocket engine can move a planet propelling a spaceship at one thousand gravities should be trivial. The vessel is sent out into deep space. Its acceleration will produce a large amount of time dilation which once achieved the ship will coast at near-lightspeed velocity deep into the galaxy. Travelling for several thousand light years away from the supernova the vessel will be unaffected by its radiation and blast waves. Once it is sufficiently far enough away the ship decelerates then turns around and accelerates on a return course to the supernova. Entering the shattered ruins of a planetary system obliterated by the awesome power of the supernova. At last it goes into orbit around the neutron star that is all that remains of the exploded star. The Ellis wormhole is deployed and inflated to its full size of two planetary diameters. Several thousand years earlier, a few years after the vessel screamed out of the planetary system at an acceleration of one thousand gravities, the aliens inflate their end of the Ellis wormhole to its full size of two planetary diameters. The huge time dilation means if the aliens peer through the wormhole they will see the remains of the supernova several thousand years in their future. All they have to do now is allow their planet to pass through the Ellis wormhole and emerge in their own future. Now they are several thousand years in the future. The worst effects of the supernova are now long one. It is safe for their planet to once more take up residence in its own orbit again. Actually it will be away for as long as it took for the planet to pass through the wormhole which at two planetary diameters won't be too long at all. No more than a few hours. This assumes a velocity of about one km/sec in passing through the wormhole. The planet won't have run away. It has simply moved itself into the future of the post-supernova and it can get back to business again. Admittedly there will be a service interruption of several thousand years, but that's not unusual as we've all had ISPs like that. If that doesn't work, and there's no good reason why it should fail, but this is a further safeguard. Keep Charles Rockafellor's planetary diameter sized black hole. Because a black hole big enough to shield the planet would be big enough to drop into the star and consume it before it has a chance to go supernova. Then the planet ends up orbiting a black hole. There you go, two solutions to the one problem, so you can't say fairer than that. I am grateful to my colleagues for their creative ideas which provided the conceptual leverage to save a planet from extinction by supernova. [Answer] ## Answer to answer Actually interesting answer from [a25bedc5-3d09-41b8-82fb-ea6c353d75ae](https://worldbuilding.stackexchange.com/a/47679/20315) (link to answer). This does not fit into a comment and some points are valuable as an answer, so it's kind of a clarification for A above. A hard sphere is bad, no no, it has to be not hard, it has to be flexible. More than that - it has to be active and actively interact with the shock wave, and extract energy. Shock wave speed is around 20'000km/s. So the sphere has to have a more complex structure then just a plain sphere. It has to have some inward parts, which will accelerate to that speed in the direction of the wave, and shape the incoming wave. And with the interaction of the shape areas of the wave, without destruction of those parts (the parts which interact with the wave, have the velocity in direction from star, heading to the outside of the sphere with relatively same speed) - jets inside jets, to let areas of the wave pass the main grid (slip in-between) and begin to extract kinetic energy, heat energy from that shock wave. (The extraction has to begin even earlier, at that shaping wave time, with de-accelerating and accelerating again part which was moved to star.) Mad skillzz about jet-jet: [](https://i.stack.imgur.com/4LTA0.png) * Yes, I did not forget about conservation of momentum, but it's the best way I could to draw a picture. * Funny note: if you will hover near planet - not orbiting, you might spend GG of fuel and fly nowhere, be still around the planet. Not so easy, but just a funny note. **A** of a25bedc5-3d09-41b8-82fb-ea6c353d75ae is a good answer because it suggests an energy extraction mechanisms for that whole situation. Also QC of those aliens, it can't be on the planet. It's just a question of efficiency. If they have reversible bits energy, they maybe do not need much of that supernova energy. If they consume and dissipate energy in the process of making calculations, placing this computer on the planet makes no sense - it can't consume that energy in a reasonable time, to make calculations of that size. More than that, they might use the supernova blast and for energy and for building that super QC system. They will have plenty of material, rich with heavy elements, in volumes hard to find in other parts of the universe and more importantly, hard to collect in one place (takes a long time, or special circumstances, like a super massive black hole in the middle of a galaxy). Even more important than energy is a possibility of having a black hole (if the chosen star is good) as the result of such explosion. Using which it is possible to extract energy from the matter they can obtain in the location - around stars and from remains of this star and other star systems. Matter of energy conversion could have a good efficiency like $\small 0.5 \times mc^2$(if my calculations and assumptions are correct) and potentially have a much greater yield than the explosion of supernovae itself over time. And those objects (Supernova remains + BH or NS) are valuable resources, so even if you have one, you might want to have more of them, and they are rare enough. This place might begin to be a place of force on a local scale (1000's ly) for them. Yes, you might get cold remains of such event of in the past, it will still valuable but could be a looong journey to power, but with all or most of remains of super nova it will be really very attractive place in therms of energy and matter, and it makes great sense to overcome all difficulties on the way to obtain it and handle the situation in more sophisticated way. Those guys have an adventurer's nature: *Everything that does not rip the universe apart, makes us stronger!* This way the supernova blast is indeed, great opportunity, which might be exploited. This antimatter spear part also isn't bad too, might work, there will be a lot of radiations, but a shield for a planet might work too. No need to annihilate everything, just slight change of impulse to form a shadow cone. Move planet, all planets, probably rob near by systems for all heavy materials (from stars too) (not necessary), add more H He to the star to make it blast when you need it, not when it wishes(at least ability to tune process a bit, and capture more neutrons, easy to burn thermonuclear fuel is also useful stuff, not easy to make fast and in quantity). Just a regular matter spear will work the same way as antimatter especially if you accelerate it to 20000 km/s(not necessary, just saves some mass in exchange for energy requirements) in case if you wish to protect a planet, and it is cheaper then antimatter, and easier to obtain. Same way as [Ablation](https://en.wikipedia.org/wiki/Ablation). So saving a planet as a bioreactor is possible. (also wave of matter from such blast is a plasma, thus using magnetic field helps to protect such spear and reduce its ablation losses) Anyway, better to move the planet away, at 100'000 A.U., the same distance as the sphere, the flash will come in 1.7 years, the wave in 15-20 years. A sphere of that size can dissipate (at 1200K) (or convert to energy) Hypernova 1e46J blast in one year. Strongly suggest to read my answer about [planet moving](https://worldbuilding.stackexchange.com/a/45273/20315), "sphere" can be done such way. Distance is good not only because energy density decreases proportionally to $\small \sim 1/r^2$, but also because blast wave is not energy-velocity monochromatic, so this way it will grow more gradual at a bigger distance. Also, some separation of materials by atom weights might happen, because of acceleration mechanisms (light pressure and such), we do not need all elements equal, some we need first, and it's would nice to use the possible situation for our advantage. Also, this way we might focus jets into nearby stars where we have also systems waiting for actions, by focusing shockwave into Hydrogen Helium jets(after removing heavy elements, and because we might not need light elements). This will focus the energy of the blast and allow star lifting using that energy when those jets arrive in star systems around. This way we might convert nearby stars to clouds (1000's of them) which we might to transport to our BH, later. Star lifting or complete disassembly and converting a star to a cloud by using the energy of a star itself is a million's million's year process and because of that using energy of supernovae in form of those jets to speed up the process is a good idea. There are also other tricks which could be possible with those jets, as redistribution of the impulse of that shockwave matter in jets and keep our shell momentum intact(or near so) which is one of the great problems in the situation. By using the energy of the incoming wave, to accelerate some part of it to let's say near 1c velocity. It helps to leave a significant portion of the matter from the star in its system, 98\% of it, and focus the energy of the blast in 2\% of the matter and near 1c speed, thus it will arrive to systems we would like to disassemble much faster, 50 times faster than it would be if we just focus 20'000 km/s jets as it is. Sure efficiency will not be 100\%, but it could be closer to that than one could expect in the situation. This way we do not need to catch all remains at once, only part we can and need atm, everything else we will catch in other star systems. As a backup plan, if power exceed our expectations. With the help of the BH and the stars around and tools, this wave can be stopped in reasonable time. The remains of the supernova, in the form of a BH or maybe a neutron star, in worse case (or it just another possibility also good one, I even do not know what to choose neutron start(NS) or BH, give me both) will be a great help in stopping the wave. Also, a great way is to launch expansion across galaxy at 0.99c speeds or fly to SMBH for goals like this answer [Why would a civilization choose to inhabit a single enormous vessel instead of maintaining interstellar colonies?](https://worldbuilding.stackexchange.com/a/47939/20315) So yes, supernovas and possibilities they offer are really attractive, but people plz plz do it well this time, not like it was with planets (ships searching planet with live and bananas to eat, 1960-70-80-...-novadays) - let's do it right this time)) Value of supernovas have to be noticed, senpai noticed you. ## Note * A supernova starting from 10 mass of sun, so at 100'000 A.U. average amount of matter flow trough sphere from star will be 0.00704 kg/m2 (or one cubic centimeter of iron), and if wave will spread during 15 year of travel, in a way let say it begins at 15y mark and ends (kinda) at 16y mark - this value per second will be much less then that (just high speed dust), but more constant pressure. We might do a lot of things with that density flow at 20000 km/s or even more, even in case of hypernova (10 times more mass). * One of your priorities is to isolate remain BH or NS as soon as possible, to prevent matter being lost in accretion processes. It's more important than even catching all of the shock wave, because it might make BH and NS inaccessible for out tools in the future, for a longer period of times then we might wish. * Isolating and lifting matter around a BH (NS) is a great way to utilize some energy of shock wave, this way we may catch more and easier. Again, clearing the area around the BH (NS) is important - it's our anchor for the operation. * A spear is a good way to clear path to internal olume/guts of the explosion, shortly after the blast, before wave will come to soap bubble sphere. * A sphere does not have to be tick, it's not a wall stopping shock wave - it's like mesh-net with soap bubbles * 15 years is more than enough time to cool down for shock wave [Supernova, Light curves](https://en.wikipedia.org/wiki/Supernova#Light_curves). * Very important moment, this [Supernova, Energy output](https://en.wikipedia.org/wiki/Supernova#Energy_output) : [](https://i.stack.imgur.com/U3uUg.png) Only 0.1 [foe](https://en.wikipedia.org/wiki/Foe_(unit)) (1foe=1044J) or less in form of gamma rays and other forms of radiation, even for hypernova, most energy is in form of *kinetic* energy of ejected mass. * Another important moment, the result of the blast are heavy elements, and after some years they already below melting points, and to contain them in compact form, soap bubbles do not need to apply any force to do that. So even parts we did not stopped may be kept compact in travel, so we will catch them as single piece later * More important we do not need soap bubbles, at all, just channels where we forming sticks from that shock wave media, yes, at 20000 km/s speed. Most of elements are Al, Si and below. [R-process](https://en.wikipedia.org/wiki/R-process) * How big, by mass, would that sphere has to be? Good question. In the "move a planet"-question, there was a pressure of gases, and sphere's used there are rather small, and they needed 1% by mass for active surface(shell) with 1bar pressure inside. The efficiency of the solution is better with size, so with 100'000 (30 million km) times bigger, it will be 1%/100'000, so 1/10'000'000 mass of the star. (Volume grows $\small \sim r^3$, thickness, and mass $\small \sim r^2$, so the mass of content grows faster than the mass of the shell.) But in the case of supernova remains there is **no** pressure to contain (solids, with a high melting point, mostly, pretty cool after 15 years), we have just press dust into solid sticks fast enough, so even less than that. (Yes, we will catch them later, in nearby star systems.) So exchanging one Gas giant for carbon in the star prior the blast (until there is some carbon and it didn't burned out) is a good idea and that's enough. So probably even no need to rob nearby systems. Those sticks we pressed, they will need some help to collect together during flight and focus their force on near by systems to evaporate stars, and yes we have to add enough of active material to accomplish that, but I think we still good with one GG. Probably we might even stop *all* sticks with one GG size of material of tool, but that is not so much important until we can focus them on near by stars. * Hypernova are not so good, as I wished, they might implode without ejecting materials, not so good, we wish ejected material. * 20'000 km/s is from [Normal Type Ia](https://en.wikipedia.org/wiki/Supernova#Normal_Type_Ia): *An outwardly expanding shock wave is generated, with matter reaching velocities on the order of 5,000–20,000 km/s, or roughly 3% of the speed of light.* * All energy of the blast, all 1046J (hypernova) might be stored in form of kinetic energy around black hole(potentially, not sure about tool, BH 30km radius may be too small for tool to do that, will leak - too small BH, SMBH is better in that sense), but not around NS ## N.B. * Do not sell or exchange information with them if they are farther than 2000ly away, and you have doubts you will get from them what you agreed for. * Ask for 10% of QC power * If they are closer then 300ly and the problem is let's say today(our time), sell it anyway(are trustworthy or not) ask for 30%. * If Venus is disassembled and they are closer than 1000ly, ask for the whole system, they might solve what they wish and take planet if they wish, and sell in case if they trustworthy(but take a hefty price, do not be cheap in the case, in all of those cases). * If they didn't pay after the event, it can mean 2 types of problem. One is big - they are not trustworthy, it will be The Pain, if even possible at all to get them from that system. The second problem is not a problem, needs to check plans. [Answer] There's only one formula for surviving a supernova--be where it isn't. Either move your planet out into interstellar space, or move your star away. The latter approach will take some of the mass off the star and thus buy you more time before the big boom, also. [Answer] Put a series of stationary smaller stars aligned in both sides of the big star (or perhaps, instead of stationary, make them rotating all with the same angular velocity). Don't care about spending a lot of fuel and energy to keep a bunch of stars stationary in relation with each other in order to fight against gravity and extreme tidal forces (all those stars would themselves provide more than enough energy for that). You will probably need to interlace a series of disposable rocky planets featuring the best refrigeration technology possible between the stars in order to build hi-tech bases able to keep everything in its correct place. Also, all of that will significantly screw up the big star rotation and make it deformed and ellipsoidal and would significantly deform the smaller stars too, but who cares? Behind the last of those stars, in one of the sides, put the planet to be protected, inside a series of concentric Dyson spheres. When the central star explode, it will quickly erode the first star in each side, which will protect the following stars from the blast. The first star debris however, will erode the following stars, and as it erodes, it exposes the second star which will also erode exposing the third and so on. The intermediary planets are disposable and doomed. Since there is a lot of stars between the supernova and the protected planet, it will take a significant time for the supernova to erode all of them. Since the supernova will last only a couple of days, eventually it will be extinguished with hopefully enough spare stars relatively unnafected between the detonated used-to-be star and the planet. The reason for placing stars in both sides is to make it gravitationally more stable, keeping the barycenter at the supernova star. Also, this would give the opportunity to build two survivable planets instead of one, so you have a backup if something go wrong with one of them. The series of debris will emit a lot of heat and light, just as all the dust and gas present from the combined stellar winds of all of those stars. Also, at least a few debris will eventually hit the protected planet. All of that will significantly damage the planet, but still much less than the supernova impact. So, use the series of concentric Dyson spheres as ablation shields and use your best technologies to keep them in place even if they are severely damaged. Eject to outer space instead of towards the planet any parts of any Dyson sphere ablation shield that became in too bad shape to continueing being useful. Also, whatever is kept in the planet, it will need to be veeeery resistant from the torrent of neutrinos constantly hitting it. Finally, there still are no guarantees. Note: Since I am the OP, I choose to not accept my own answer as correct. Please, beat my answer with something better. :D [Answer] A supernova explosion would annihilate any known form of matter, so a solution must involve not getting hit by the supernova. You could move the planet to a larger orbit to reduce the energy of the incoming blast to something manageable, but that feels like violating the spirit of the "no running away" rule to me. So if you can't block the supernova, and you can't move the planet, how could you survive the blast? Easy! Use the same principles employed by the Alcubierre drive to curve spacetime between the planet and the star so that there are no straight-line light paths between the two. The star explodes and the outward burst of energy and matter flows around the planet. The quantity of spacetime curvature can be tweaked to allow for some of the matter and energy of the explosion to reach the planet (within the bounds of what can be shielded against), if the aliens need to do some data collection about the supernova itself. [Answer] Since you seem to be looking for hard science answers, one thing to note is that it was recently proven that what we thought was the minimum energy needed to perform computation isn't the lower limit. Your linked crypto thread is now out of date. <http://phys.org/news/2016-07-refutes-famous-physical.html> > > "Now, an experiment has settled this controversy. It clearly shows that there is no such minimum energy limit and that a logically irreversible gate can be operated with an arbitrarily small energy expenditure. Simply put, it is not true that logical reversibility implies physical irreversibility, as Landauer wrote." > > > Some of the limits of computation, how much you could theoretically do with a certain amount of energy are based on what appear to have been incorrect beliefs about information processing and entropy. > > It will push the research towards "zero-power" computing: the search for new information processing devices that consume less energy. This is of strategic importance for the future of the entire ICT sector that has to deal with the problem of excess heat production during computation. > > > It will call for a deep revision of the "reversible computing" field. In fact, one of the main motivations for its own existence (the presence of a lower energy bound) disappears. > > > [Answer] If you live in the fictional universe of E.E. Smith's *Lensman* series create a hyperspatial tube (sort of an early version of a wormhole) between your solar system and another one. Put one mouth of the tube right in front of your planet so your planet will enter the tube. Place the other end of the tube in the other solar system at a location where the velocity and direction of your planet as it exits the tube will be exactly right for the planet to go into a nice almost circular orbit of the new star. Be sure that there are no planets in the new solar system in positions likely to destabilize the new orbit of your planet. And close the hyperspatial tube **before** your old sun explodes! The *Lensman* universe also has lots of different types of force shields that can protect spaceships and planets from the ray guns of other space ships. It is possible that the ray guns are so powerful that they could vaporize planets and are as energy dense as exploding supernovae. Thus any force shields that could defend against such powerful ray guns might also defend and protect against a supernova. The planet Tralle, or Trallis III, capital of a space empire, was defended by the fortress planet Onlo, or Trallis VII, that should have been about a billion miles away. The weapons on Onlo were designed to destroy attackers after they had nearly reached ground level, but I suppose that nearly ground level actually meant billions and billions of miles, since the planet Tralle was protected by Onlo. At that time both sides in the space war were capable of attacking target planets with multiple mobile planets at a time to smash into the target planets, so the weapons of Onlo must have been capable of vaporizing multiple planets simultaneously and almost instantly at distances of at least billions of miles. Thus it seems likely that the ray guns on Onlo were powerful enough to have an energy beam density at least equal to a supernova at equal distances. Since the government on Tralle could not 100 percent trust the garrison of Onlo to not turn against them, they probably had Tralle protected by a force shield strong enough to stop Onlo's ray guns and thus a supernova's energy. The *Lensman* universe also has energy screens that can convert the cosmic energy in interstellar and intergalactic space and turn it into usable energy. It is possible that such screens could be adapted to convert the energy of a supernova into harmless and usable energy to power force screens to protect against any supernova energy that gets through the power converter screens. What if you don't live in the fictional *Lensman* universe and your technology is limited to that which Earth Scientists in the year 2015 consider possible? Then your in big trouble! If some form of time travel is possible, and if you dare to risk erasing yourself from existence, and other time paradoxes, go back in time millions of years and begin the process of slowly moving your planet tens of light years away from your star over a period of millions of years before it becomes a supernova. Here are some discussions of planet moving: <https://www.google.com/search?q=how+to+move+a+planet&ie=utf-8&oe=utf-8[1]> And if it might take many thousands of years to move a planet's orbit a few million miles closer to or farther from the sun, it obviously could take millions or billions of years to move it light years away from a supernova. So if you just found out that your sun is going to be a supernova soon, you need to go back int time at least millions of years in a time machine to start the process. [Answer] **It's time to build a world engine and surf the rainbow.** So what we're going to do here is create a world engine which will allow you to pilot the planet away from the Supernova at a rate which will keep you at it's edge in order to avoid being obliterated while simultaneously allowing for maximum data collection. The engine is going to be powered by the Supernova itself, and in order for the engine to function, the spool will need to be able to dynamically adjust to ramping fluctuations in potential energy. You are also going to require a star capable of sustaining a life cycle on your planet. This star will need to be placed directly opposite the supernova approach vector. Both your planet's and the stars orbit of the supernova will need to be fixed so that the planet eclipses the supernova at all times. The engine will need to operate independently of the planet's rotation while remaining fixed in a single location. This is simple to accomplish with a dual frame setup, the inner frame fixed to the planet in equidistant points for even distribution of force. Once all of this is accomplished, the supernova will supply the power needed to elevate the electromagnetic force necessary to create a planetary shield that will prevent radiation from cooking your planet. As a secondary application, the energy can be redirected into a powerful blast resulting in an equal and opposite reaction pushing the planet away from the expanding supernova. The excess power would be channeled into holding the star at it's fixed point by propelling it before the planet. In effect, you will utilize the supernova as a wave, and surf the rainbow holding a torch ahead of you to light the way. ]

[Question] [ I know a submarine would NOT make the greatest spaceship in the universe, but could it allow people inside to live in space? A submarine can resist pressure, can hold oxygen inside, and there is a heating system... I think radiation would cause some issues, but is it the worst problem my poor hypothetical submarine people will encounter? If a submarine with people inside was suddenly send into space, would they survive for a while? **Other questions:** * If they don't, what will kill them so soon? * If they do survive for a while, how long? * If they do survive only for a while, what is going to kill them first? [Answer] Okay, hold on. Let the actual submariners weigh in. I spent 8 years of my life in the United States Navy aboard Los Angeles Class submarines as a Nuclear Electricians Mate. I have a background in engineering and radiological controls as a result. Please treat this as an extended comment - the answer as given is, in fact, no. But there are number of misconceptions that you guys are flailing around. I can unequivocally and without a doubt say that it would not explode. The air would leak out from around the shaft that makes the screw go around, but you'd likely weld that shut before spending several billion dollars flying something that heavy that high. You'd also have to seal a few cable ways but sonar doesn't work in space, so no big loss. As far as oxygen - (classified). But that kind of machine uses very very clean water, and uses it pretty slowly. It's not like it needs access to the ocean to work. Look up commercial grade systems and you'll understand. As far as radiation - bring it. The whole charged particle thing is simply incorrect. A beta particle or an alpha particle simply won't cause an avalanche cascade in steel. There's not a significant neutron source up there. That leaves the gamma rays that everyone has to deal with. As far as power - (classified). But no nuclear reactor anywhere can operate without a heat sink. That's just thermodynamics. And submarines sink heat to the Main Seawater Expansion Tank, aka the ocean. Period. No water, no power. Forget it - no workarounds. As far as burning up - the ISS is a thing that is real. Polish it shiny and paint it white and there is no real risk of burning up. The reactor is down so, meh. The biggest thing that everybody missed is that all submarines are built assuming that **gravity is a thing that exists**. The entire design of a nuclear reactor must take into account this very basic thing. Shoving something like this into microgravity means water starts coming out of the tops of tanks and pooping gets real risky. Steam that should be on top gets on bottom and water destroys your turbines while us enlisted men take turns opening various valves to naked vacuum because we like to watch things disappear into space - which is the real reason why we'd all end up dead from hypoxia. [Answer] I'll start with the spoiler: They are going to die. I'm not sure exactly how long it will take (because I can't find details on reserve oxygen capacity or submarine nuclear reactors...might be classified)...but they'll either suffocate or cook--and whichever happens will be their choice. A submarine's main limitation to how long it can stay under, in the ocean, is food...but this changes dramatically when they go to space. The reason that a submarine can stay underwater so long is that it produces its own air from the water around it. It pulls the water in, splits it into Hydrogen and Oxygen with Electrolysis, and vents the Hydrogen back into the ocean. It deals with the Carbon Dioxide by use of scrubbers that use amine as a scrubbing agent...the CO2 is then vented into the ocean as well. The sub has oxygen tanks where it stores extra oxygen, but there isn't nearly enough in there to last as long as their food stores would. This is why power failure on a sub is a big deal. It stops producing oxygen for the crew to breathe. When their oxygen starts to run low, they could start taking their reserve of drinking water and feeding it into the oxygen generator to produce more, but...again, this is a finite supply. While it is possible that they would dump all of their drinking water into the oxygen generator, and thus die of dehydration, it is more likely that they would attempt to ration things so that they would run out at about the same time, thus allowing for the maximum possible time in order to be rescued. But, there's a bigger problem. A nuclear submarine dumps the heat from its reactor into the ocean. A diesel sub does the same thing with the heat from its engines. In the ocean, this is great...because water is awesome at absorbing energy. The vacuum of space? Not so much. Contrary to popular belief, the biggest temperature danger in space isn't freezing to death...it's burning up. On Earth, we can shed heat via conduction, convection, and radiation. The first two are dependent on *something* being present for the heat to be absorbed by...and radiation is massively less efficient than the other two. In space, you only have radiation. Think of a submarine in the vacuum of space as the inside of a thermos. Big insulated tube. And you have a nuclear reactor as a roommate. Things are going to get very, very hot. So, this is where you have the choice. Do you shut down the reactor so you don't all burn to death, and hope that whatever low-power reserve generator you have doesn't either run out of fuel or cook you all before you run out of water to convert into air? Or do you leave the reactor running to maintain effectively unlimited power, but burn yourselves to a crisp within short order? Either way...not a good ending. [Answer] ## Leaks * A submarine is **not** designed to hold air *in*. * A submarine is **not** even designed to keep water *out*. * A submarine **is** designed to keep the rate of water ingress below the rate at which the bilge pumps can remove it. The occupants will die in minutes as the air pressure decreases below the level needed to sustain oxygen flow across lung membranes. If your submarine is being launched from the surface of an Earth-like planet, this will happen before it reaches space (100km up). Consider [Helios 522](https://en.wikipedia.org/wiki/Helios_Airways_Flight_522) where people passed out and died somewhere under 10km up. [Answer] Short answer: NO. It'll pop open almost instantly - not like a balloon, but split on a join or seal and leak air out. Submarines are designed to withstand compressive pressure, not de-compressive pressure. Conversely, shuttles are designed for de-compressive pressure. This is why we don't fit propellers to our shuttles and send them underwater. :P [Answer] Well, a submarine is primarily designed for pressures on the outside trying to crush it. However, I expect that the same seals that keep water out, will help keep the air inside. They of course will have no propulsion at all except for evacuating the ballast tanks. Some of the subs are designed to survive six months under the ice caps on missions. So in theory the submariners could go for months. However, there are several things causing a problem. The first is weightlessness in a cramped place designed for gravity. The latrines will be almost useless, causing sanitary issues. People who aren't trained in freefall will be breaking bones, etc. in the confined spaces. On top of that even though the seals will do a decent job of keeping air in, there will be leaks because the they were designed for different things, air 'pushing' out is vastly different than water 'pushing' in. So if broken bones and sanitation don't kill them, likely asphyxiation will likely be the last killer. [Answer] Submarines do not have the same kind of [insulation](https://www.youtube.com/watch?v=eURy8NskhGM) that [space stations](http://science.nasa.gov/science-news/science-at-nasa/2001/ast21mar_1/) have, so the [heating/cold](https://www.youtube.com/watch?v=0CccTH0gXso) might be an issue. Yes, both of the clips there are ships without power freezing, but they are space ships with space insulation and the submarine is designed to combat the constant ambient ocean temperatures. Other than that, I would think the layers of metal would protect from most radiation for the duration that they are in space. They have no useful sensors or means of navigation. Perhaps the periscope for sighting and change with the ballast tanks (usable only once) could help them make a slight correction. They would have to be unusually precise on where their ballast vents are, not a common thought when in the ocean. They should be safe from air leaks, because air leaks would make bubbles in the ocean and be a bad thing for a submarine. However, submarines are designed to hold up as the water pushes in on all sides. In space, the air inside is pushing out on all sides. Small things like this are assumptions engineers often make for the intended use, and often cause trouble when the thing is used in a different way. That insight is derived from my day job as a developer, working with other developers' code. [Answer] There is no way to launch something as heavy as a submarine into space. A nuclear submarine weighs about 13 million pounds -- that's calculated because there is no way to weigh it in any conventional sense. There is also no way to tip it upright outside the support of water -- it's structure would not support its own weight. The entire space shuttle weighed about 165 thousand pounds. That is to say, an average submarine is about 80 space shuttles! The apparatus needed to launch a pound of payload into low earth orbit weighs between 25 and 40 pounds. [The Saturn-V that launched the moon shots had the best ratio, about 13.] The device needed to launch a submarine would weigh more than a skyscraper and no one could build such a thing. Things designed to go into space are always as light as possible. Special materials (e.g. beryllium) are used and the layout of material is always just enough to stand the forces of launch. Some rockets are so flimsy that they cannot stand on their own (Soviet rockets had a tower that retracted just as the rocket motors started!). The LEM that landed on the moon was made of materials so thin that you could easily have kicked through it's walls with your foot. Even the space station, which required weighs about 900,000 pounds -- about 1/14 of a submarine -- and it required 40 launches to get that much into orbit. One cam imagine a submarine in orbit but why? [Answer] (from the dead) Sean makes a great case why and why not an un-modified 688-class (or comparable design) would work. My background: Sonar tech on a 688 Flight II boat, circa early 90's. If you were a crew on a nuclear submarine and suddenly found your whole ship suddenly teleported into space, you would not be happy. Gravity, power, life support... all those things that work in the vacuum of space are now missing. You wouldn't instantly die, but life would be measure in no more than days, possibly hours. Leaking seals would let air out and the black hull would collect lots of heat through radiation. If that's the core question, will a submarine make a good spaceship, the answer is no. That said, me and some buddies played a thought experiment on how to convert a submarine to a space ship for RPG campaign. A few caveats... 1) Star Trek style technology is available... impulse drives, warp reactors, anti-gravity, etc... 2) Yamato style stealth engineering. We don't want to look like we're building space ships, so let's modify an existing naval vessel. We basically replaced the fission reactor with a matter / antimatter warp core, and turned the entire after section into a Star Trek style warp nacelle. Added gravity control, sensors and propulsion / helm controls. For giggles, we left the interior layout as untouched as possible. The funny thing is, our design for the control center (this was about 1992 as I recall) shares a lot with the publicly available images of the current Virginia-class subs. It should go without saying that a submarine makes a better starting point than a surface vessel. A submarine hull could be re-engineered into a spaceship, if you had sufficiently advanced technology. Under most economic models, it would be cheaper to build a purpose-built spaceship, but I'm sure a scenario could be made to compensate for that. [Answer] The ordinary (not nuclear-powered) submarine cannot stay submerged for really long, as it uses battery power to run various required systems. It may also run out of other necessary resources like compressed air, and it may eventually loose some air being not completely airtight. Some devices may not run in the absence of gravity. However I think that at least with the help of heroic attempts the crew may be able to survive for many hours if not days. [Answer] in real life, the crew might live for hours, more likely minutes as has been covered. In fiction, it's been done pretty well by John Ringo and Travis Taylor in <http://www.baenebooks.com/p-613-vorpal-blade.aspx> of course, his setup depends on an alien device.... but it's a fun read, a lot of the science is sound given the premises made in the name of a good story :) Ranging in topics from the best gun to kill armored space monsters to particle physics to cosmology, Vorpal Blade is a return to the "good old days" of SF [Answer] Yes Most unmodified would fail but it depends on the sub, not to mention the increasing heat warping metal. A hardy sub might survive with proper cooling and maintenance. They would definitely require hull modifications, sealing the propeller and replacing the propulsion system, removing and sealing the fins, and sealing the water containers. I would be safe and give another hull layer along with extra inner steel . Then the sub could survive but you need life support for the crew. Other than that I don't see why not. Just make sure your devices work in free fall, and modify them if necessary. [Answer] A submarine would make a great spaceship. I don't know why the other answers say otherwise. The difference between a spaceship and a submarine aren't that large. Of course it isn't automatically ready to go to space, it would need a lot of improvements, but not as much as you would think. If the right precautions are taken and improvements are made, it would make a decent spaceship. ]

[Question] [ After the [Brexit](https://en.wikipedia.org/wiki/United_Kingdom_European_Union_membership_referendum,_2016) vote, one of repeating themes was: "If only knowledgeable people were allowed to vote and dumb people were not allowed to vote!" Let's have look at this political system closer: **Assume:** * Everyone of legal age is allowed to vote. * All votes happen through electronic system. * Before you can cast your vote, you have to pass a test on the subject you are voting on (see examples below). * You will be presented voting options after you take the test (even if you failed). * But if you failed the test, your vote is not counted. * About 80% of those who vote pass the qualifying test. * The electronic voting system is failsafe - no one wants or tries to hack it (Strong assumption, I know. But the scope of this question is to aim at the political system and not on possible flaws in voting machines). **Question: Will this system provide any value added compared with the current democratic system?** **Examples** Before casting a vote for American President you should know what each president actually can do. Before casting a vote to leave EU, you should know what the European Union is. For narrowing scope of this question down, assume that this system is introduced "right now" (Earth, current day and tech) in USA. [Answer] What you're describing is essentially a [literacy test](https://en.m.wikipedia.org/wiki/Literacy_test). The biggest concern here is that this test could be manipulated to exclude certain groups of people. For example, the [state of Louisiana used a test to try to disenfranchise black voters in 1964.](http://www.dailymail.co.uk/news/article-2831095/Harvard-students-sit-1964-Louisiana-Literacy-Test-black-voters-pass-allowed-polls-single-person-FAILED.html): > > A group of Harvard students were recently asked by their tutor to sit the 1964 Louisiana Literacy Test - a notorious document with confusing questions that was used to stop black citizens from voting. > > > Just 50 years ago, states in the South asked voters who couldn't provide proof of a fifth grade education to pass the test in order to be eligible to cast a ballot. > > > The test was intended to disenfranchise African-Americans, who in order to pass had to correctly answer all 30 questions in 10 minutes. > > > **Despite their Ivy League pedigree, none of the students managed to pass the test** > > > As the quote above shows, these tests can be manipulated to determine who should vote. **The most likely outcome to this test would be that whoever controls the test will control the government.** Some commenters have suggested that the test could be unbiased. Even if this is true, the way that it is conducted (allowing everyone to vote, only counting some) runs the risk of angering the losing party. Whether or not the quiz is truly unbiased (which is difficult to do), there will be the accusation of bias. If a country gets to a point where a significant portion of the voting group does not feel like their votes count, civil unrest will occur (see Brexit or the Trump and Sanders campaigns). In addition, I have serious doubts about the possibility of a truly unbiased test. Something as simple as asking about a state capital in a certain region of the country would disproportionately favor voters from that region. Since voters tend to cluster with like voters, this could unintentionally (or intentionally) remove more voters from one side of the political spectrum due to location. [Answer] The disadvantage I see here is who decides what is worth knowing? Not only does this open up a can of worms regarding discrimination and corruption, but it ignores some very interesting aspects of humanity such as the 'wisdom of the crowds': > > The notion that a group’s judgement can be surprisingly good was most > compellingly justified in James Surowiecki’s 2005 book The Wisdom of > Crowds, and is generally traced back to an observation by Charles > Darwin’s cousin Francis Galton in 1907. Galton pointed out that the > average of all the entries in a ‘guess the weight of the ox’ > competition at a country fair was amazingly accurate – beating not > only most of the individual guesses but also those of alleged cattle > experts. This is the essence of the wisdom of crowds: their average > judgement converges on the right solution. > > > <http://www.bbc.com/future/story/20140708-when-crowd-wisdom-goes-wrong> Or in other words, while you may think it is silly that some people would vote to remain or leave the EU without knowing what it even is, it may still be a key contributor to good decision making on the whole. [Answer] > > After Brexit vote, one of repeating themes was: "Only if knowledgeable people were allowed to vote and dumb people were not allowed to vote!" > > > Looking at the Brexit vote in particular, I'm not sure that this would matter. The particular problem with the Brexit vote wasn't that people didn't know what the EU was. The main problem was that voters didn't believe the consequences that were threatened if Brexit passed. But to prevent that, you would have to essentially allow the anti-Brexit people to write the voting test. There are two problems with letting anti-Brexit write that test. First, if Brexit had failed because of pro-Brexit voters being disenfranchised by a voting test, it wouldn't have drawn off the pro-Brexit anger. It would have let it not only fester but grow. All those people regretting their pro-Brexit votes would be angry about not being able to vote. They'd be even more pro-Brexit than previously. The second problem is for other votes. Maybe you are anti-Brexit and happy enough to have the establishment stomp it. But what happens when it's your side that wants something that gets blocked by the test? Will you simply be happy that your side fell to the more informed side? Or will you be angry too? Now there are groups of angry voters who want to get rid of this undemocratic voting test. There are two possibilities. The first is better. There are enough voters opposed to the test that it gets voted out. The second is that people are just plain angry. What happens when people feel powerless **and** angry? They resort to violence. The great thing about democracy is that it allows people to feel that if they could only convince others to vote with them, change is possible. If people learn that that is impossible, then we go back to the old way of changing government: violent revolution. [Answer] > > Will this system provide any value added compared with current democracy system? > > > The crux of this question is, as always when dealing with politics: **to whom?** For that reason, let us examine the change in value to various demographic slices. These are not meant to be comprehensive, nor mutually exclusive. # Value for the Ruling Class For the purposes of this discussion, the 'ruling class' are those who have disproportionately large say in the affairs of government and policy. In the United States currently, this can loosely be defined as people who are, on average, better off, better educated and/or have some means to spend a significant amount of their time embedding their judgment in actual legislative or legal policy. Generally speaking, on average, people do not give up power they have willingly. Some will choose to do so for philosophical reasons, and some will do so rather than risk something else (life, assets, etc.). But there are only rare occurrences where an enfranchised class simply give up power they have. Therefore we can assume that the current ruling class would not accept a 'filtered' voting system unless one of two things happen: * They maintain or increase their demographic's control of the political machinery. * They are being forced by a superior effort to accede control in this manner. Addressing the latter first: it is hard to imagine what movement would arise that would put as a central tenet a filtering of the voting system. Typically this happens in the reverse: peasant revolts against landed nobles, or minorities marching to be given the vote. It's hard to imagine that a movement would say, "We are here to exclude 'x' group, which includes a large number of ruling class members, and will do 'y' problematic thing if not given this concession." Perhaps I lack imagination, though. What this means is that it's reasonable to assume the ruling class would have a large hand in designing the details of the system - where, as always, the true devil lays. Specifically, they would have to decide these broad areas: * Who gets to decide what questions are asked for a given vote. * How changes in who gets to decide are effected. * What sorts of questions are appropriate for the test, which the people in charge of coming up with them would have to adhere to. We can assume there would be a large number of such rules. (As an aside: the voting in the US today is fairly complex because a number of edge cases must be addressed at every polling place, such as how blind, deaf or otherwise disabled persons can vote, or how information is communicated to those who don't speak English. Therefore we know the rules around the questions would be quite numerous.) Let us consider the direction of politics each of these effect. ## Who Decides the Questions For a long time institutions have taken on the personality based on the goals they were originally formed around. For instance, while the Department of Agriculture is ostensibly about growing food, one of it's early goals was to promote the trade of food. Even today 'trade' is one topic on it's website and many of it's policies are actually purely economic in nature, rather than scientific or even very food-related at all. This is because promoting American food was very important to the US economy at the time of the founding of the Department of Agriculture. So the **climate** in which the 'filtered election board' is created is *very* important to how it turns out. The reason this is important is because it selects the **biases** that become 'unseen'. All humans are biased, but we tend to overlook certain biases based on our environment. These unseen biases will enfranchise certain parties over others. If the climate is one of rampant nationalism, for instance, you might expect an institution that produces questions deeply embedded in American culture, thus confusing recent immigrants. If the climate is one favoring older Americans, it may use references to things that happened prior to the lifetime of young voters, thereby impacting their ability to answer correctly. Even maths questions can be asked using [different methods](https://nrich.maths.org/5612), and if you are unfamiliar with the way a question is presented it can inhibit your ability to answer. Were you taught math using [new math](https://en.wikipedia.org/wiki/New_Math) or [reform mathematics](https://en.wikipedia.org/wiki/Reform_mathematics)? If the writer of a question comes from a different context (educational, lingual, cultural, etc.) than you it will impact your ability to answer correctly. Further, we know that because [people tend to hire people similar to themselves](http://www.asanet.org/sites/default/files/savvy/journals/ASR/Dec12ASRFeature.pdf) that these biases will linger, even if the political winds drift to different shores. ## How Changes in Who Gets to Decide Are Effected Given an institution of some variety to decide questions, we also have to ask how the members of that institution change. This is a classic governance problem: you can go the route of the Supreme Court and once elected to the Filtered Election Institute you are there for life. This is very good if you happen to be good, and very bad if you happen to be bad. It could be a randomly selected, rotating set of people, in which case most of the institutional knowledge will reside not in the decision makers but in the 'hidden' support staff and tools. This makes detecting problems very difficult and pernicious, but to a degree blunts the amount of damage they can do. It can be appointed by the current ruling power, which has some of the problems of both: as we see in [gerrymandering](https://en.wikipedia.org/wiki/Gerrymandering) whoever is in power is liable to modify the rules in such a way as to extend their power. ## What Sort of Questions Are Appropriate There is a very difficult nut to crack here, in terms of justice, and it has two faces. The first face is one of **aroused bias**: as [explained here](http://www.cbsnews.com/news/why-question-order-changes-poll-results/) even the order of questions will affect the opinion of the person being polled. If I am asking about Presidential candidates, what I ask about them will matter: `How many years of foreign affairs experience does Guy DeFalt have?` will prime the test-taker to think about foreign affairs, rather than some other category. The second issue is one of **indirect filtering**. Someone who is very good at critical thinking cannot deduce the founding date of the European Union, nor be able to name the member states. Someone very good at memorization, though, could. There are plenty of examples of [savants](https://en.wikipedia.org/wiki/Savant_syndrome) who might not be able to reason about whether a thing is good who would nonetheless know a great deal about that thing. What this means is that the 'intelligence' being tested is unlikely to be in line with the 'intelligence' that is needed to make a good decision. Instead, it becomes a lever to select who gets to decide: perhaps someone who has been prepped on how to formulaically respond to the questions, or people who adhere to a particular party line. How the decision of what questions are appropriate is decided, along with what additional information is provided with the question, will decide who 'seems' smart enough. ## Final Ruling Class Notes Naturally, all of these seem to favor the ruling class, and with most systems that filter out some members of a nation, it tends to entrench the ruling class (even if that class is poorly defined). For this reason American democracy, a 'representative democracy' is often correctly named a 'Republic': the difference being that in a Republic only certain members are allowed to vote. But wait! Isn't everyone in America allowed to vote? The answer, as betrayed by your description, is no: > > Everyone of legal age is allowed to vote. > > > 'Legal Age' is one way the 'ruling class' in America maintains it's control. It is assumed that people under a certain age are too dumb/uneducated/biased/controllable to vote. In essence *we already filter the vote*. And the effects are clear: we tend to vote towards things that favor adults, whereas concerns about early education, child health, and so on must be dealt with indirectly by people who do have a vote but care selflessly enough about those issues to be the voice of children. The effect varies depending on the specific issue, but the notion that you can give 'lip service' to eduction, for instance, is common: use it for good press but never fund it as well as, say, the military or social security. It is hard to think that this state of affairs is really in the full, 100% best interest of children, and so we see an effect on the filtered-out class: their actual best interest is a national second-interest. This specific form of filtering became a hot issue during the [Vietnam War draft debate](https://en.wikipedia.org/wiki/Opposition_to_United_States_involvement_in_the_Vietnam_War#Draft) when children unable to vote were nonetheless forced into military service by ruling class (those who could vote). They weren't even allowed to drink legally at the time, and it took the casualties of WWII, Korea and Vietnam to finally force the political machinery to address the filter. # Voters Next we turn to people who vote. Does this system provide value to the electorate? Presumably the idea is that they want a better result, to have their voices heard better by filtering out voices that should not be heard. ## Better Result The real issue with any filtering situation is determining whether one result is 'better' or not. Philosophically this is a problem: if you decide 'x' result is 'better', and you tune the system to give you 'x' result, then you're effectively removing democracy. The value added here, then, is that the electorate **feels** that the result they wanted is the result they got, rather than mostly feeling like they didn't get what they want. The value is faith in the system. Ironically, you have to look not-too-closely at this form of democracy to net this result. A test filtering for critical thinking might undo the value you get from the test by choosing only those who will not easily be duped by a biased system. It is interesting, too, that there is an implied assumption here: that the nation would make better decisions if only the process by which they made decisions was better. But it assumes the bottleneck is the decision process and not the decision makers: this is akin to the difficulty with testing-based education. Even with the best tests you might find the best decision makers, but you're not guaranteeing an overall improvement in the decisions being made - suggesting the only 'better' results can come from an overall improvement in the quality of voter. (Which is impeded by expense.) ## Effort One aspect of this is that it requires a great deal of additional effort on the part of voters. Already in the United States voting levels are very low, and in particular people tend to only vote on big-ticket, high-level elections. If they vote on lower-level elections, it is often only when they are voting at the same time for a higher-level election. Often they don't vote because voting is difficult and time consuming. Sometimes voters only vote on the one thing they care about and leave the rest of the ballot blank (begging the question as to whether they would take the time to do the test first, or stick around and take the test after if that was the ordering). By requiring voters to 'study up' to vote, and to take additional time to answer questions the system becomes one where, naturally, more people self-select out: it's too much effort. Therefore the value to the voters is that those who do vote are **particularly motivated**. Via another method, Robert Heinlein asserted this 'limited democracy' in his book [Starship Troopers](https://en.wikipedia.org/wiki/Starship_Troopers#Politics). A system requiring highly motivated voters is likely to be one that has many such artificial barriers in place: a meritocracy whose quality is proportional to the degree with which the barriers are in line with what they are testing for. The specific effects of this could be varied, and interesting to play with. As a quick aside: it would also greatly increase cost to run a specific polling place and elections in general. Recounts become not only recounts of votes but of filtering tests. The length of the election is potentially increased in close races, and the value to the motivated voters feeds back on itself: the next time you have to be even more motivated knowing that your vote may not be correctly counted even with all the effort you're expending. Each new barrier or filtering test increases the chance of something going wrong or the system skewing in an unintended way. Faith becomes doubly tested. # Non-Voters Another interesting question is what value is presented for non-voters. The system proposed has a particularly curious tangle: **the voter doesn't know if they're a voter**. Unfortunately, lacking imagination, I'm hard pressed to come up with even a scant value for the voter here. Already, we exist in a system where we must place great trust in the machinery to count our vote. Votes are often accidentally discarded or lost. Hanging chads and marking disagreements abound - and there are electronic equivalents. In a system where there was both a ballot and a test, and a failing score on the test invalidates the ballot counting and **verification** of the count becomes problematic. I, as a voter, don't know that if my time was well spent or meaningless. I have no way of verifying myself that the ballot was cast. The primary value here, actually, seems to be for those who would foment anger at the system: they could easily point to the system and say, "For all you know, you voted and they did what they wanted anyway!" We can easily imagine a Nigel Farage, post a 'Remain' vote saying, "Well, I just can't imagine all these impassioned people having voted 'stay': the test is rigged, the system is rigged!" And, of course, in this proposal it *is* rigged. But it seeks to create a larger class of non-voters, on the assumption that 'intelligent' voters would vote 'better'. Without knowing if your vote counted (if it was 'good enough'), it's hard not to feel like you were in the 'stupid' class of people if what you wanted didn't win. If things start going wrong, how can you not feel angry and powerless? That sense of powerlessness is useful for those who would make marked, large changes to the system. People act funny when they suspect they might not be at the cool kids table: that chaotic behavior is rarely good for stability (or that matter the ruling class). # Conclusion As indicated, a lot would depend on *how* this system was implemented. There are certainly modifications or implementation details that could be utilized to enhance value for some people and reduce damage for others. But the nature of those details would affect the resulting 'world' that arose. Certainly it would change how power flowed from the electorate to the decision makers, and the notion of a quantum vote (did it count?) is intriguing in it's own right. The outcomes are very hard to predict, but it would certainly seem to hurt the disenfranchised and help the ruling class: the question then is if the hurt is less than the total value to the system. (Which, indeed, is a *very* broad question.) It seems fairly obvious why filters have been removed over time rather than added: inclusivity leads to less anger in the general populace. (Remember, the US originally only allowed land owning men to vote: filters have changed greatly over the years!) Based on what drove the removal of those filters we can see what we would be (eventually) getting by putting them back into place. But to directly answer your original question: would there be value added by filtering a vote based on a test? Yes, some value would be added for some people. The specific people would depend on the details of how and what precise filter was added. Value would be taken away from other people, already likely under-represented in the system. An 'educated' vote is likely to come at the cost of a populace with less faith in that voting system. In the short term, the best interests of those making the change are likely to be best served. In the long term, it's likely to be a less stable system. # Addendums and Asides * To bring Brexit back into this: those who voted to Leave often did so because they felt they lacked a direct representative voice in the EU politics, and were being screwed by the ruling British class and the EU bureaucrats. The EU was not benefitting them directly. While it may have been bad for the system, they used this vote to voice the fact their votes elsewhere seemed to not be counting - and by 'not be counting' I mean that their best interests were not being served. In this manner the referendum was an **indirect vote** on the quality of the system: the voters know something is wrong, even if they don't know the immensely complicated economics of the EU-British situation. When they're asked about the EU, they voice something is wrong by voting for change. Simple votes are rarely about a direct, singular, easy-to-understand, up-and-down issue. * You also posit `80%` of the populace must pass. It's unclear whether this is decided 'for that election' (i.e. the top 80% of the test takers have their vote counted) or 'for future elections' (in which case the questions might eventually drift to 'so easy to answer anyone can do it'). In either case it begs the question as to whether voters should care about the test: if more than 20% of the voters *answer no questions* then they all equally have a chance to have their completely unvalidated vote being counted. In fact, depending on how you 'score' the test, their votes may count more than someone who tests badly, or someone who answered test questions randomly. This is the question as to whether a non-answer is penalized more or less than a wrong answer. This is a *big* deal, and has plagued college entrance exam tests for years, but in the case you posit it suggests the 'smart' thing for voters to do is universally decide not to take the test. * A security flaw also arises if the test must be passable by 80% of the people. In this situation you can probably game the system by answering just enough of the questions correctly, and then the remaining questions can be used to encode **who you are**. This is a problem because it means that third parties can positively identify which vote was yours, and determine whether you voted as they wanted you to. California has roughly 40M people (the most populous state), meaning that with as few as eleven 'optional' five-response questions you could easily positively identify any single voter. (Can you ascertain the voter has enough knowledge with fewer than 14 questions?) Meaning people could be coerced into voting. I'm sure there are even more efficient ways (i.e. fewer questions needed to uniquely id an individual) to do this. * The proposed system also suggests that the questions are topical: that is, they relate to the vote. The Filtered Election Institute would have to know *an immense amount*, or outsource expertise, to determine good questions to test for competence in any given area. Note that the current educational system struggles to do just this, and their sole mandate is educating and articulating the differences in education between people. The FEI would be a *very* interesting institution because the shortcuts it chose would have profound impacts. Great fodder for a dystopian novel there. [Answer] There actually is such a system in place today: the market. In a market, the questions are disaggregated into individual choices about individual goods and services, and the answer isn't jut a binary Yes/No, but on a sliding scale (how much is it worth to you?). In a market and market economy, you "vote" every day and cast ballots with your dollars. The BREXIT vote did have a market counterpart: the London and global Stock Exchanges. While the result of the BREXIT vote caused a short term drop in market valuation, the supposedly "smart" people who predicted disaster were proven wrong since the markets recovered remarkably rapidly. In a sense we are already "voting" in the market, the fluctuations in the market caused by announcements of political policy, the rise and fall of various currencies and even the movement of people from one jurisdiction to another (voting with your feet) are all market based responses to political policy. The real trick is to go forward rather than backwards with this idea, using markets to *set* policy rather than to *respond* to policy. One possible way would be to "auction" legislation. Today this is done through powerful lobbyists using financial and other manipulation to influence lawmakers. Because this isn't transparent, and generally lobbyists are spending their money in the hope of a return (i.e. policies which favour them or disadvantage their rivals), the outcomes are fairly narrow an only apply to the favoured few (incidentally, this was one of the key reasons that the BREXIT vote for leave won; the EU is notoriously non transparent). Rather than "auction" legislation in private, proposed legislation can be put on the internet, and people can "buy" votes. While this might initial favour the rich and powerful, they will be spending money which (ideally) would be used to run the functions of government, and reducing the amount of resources they have for other things ([Frédéric Bastiat described the concept of Opportunity Cost in his 1860 essay: *Ce qu'on voit et ce qu'on ne voit pas*](http://wiki.mises.org/wiki/Parable_of_the_broken_window)), which could eventually even things out as they spend more time and resources on politics than wealth creation. Like every other system, there are opportunities to game the system and otherwise discover unexpected or unwanted outcomes, but this really puts your money where your mouth is, and allows you to vote on a continuing basis for or against laws and regulations rather than simply at periodic intervals. [Answer] Realistically a system which requires such qualified voting would have to be some sort of direct democracy. It is not really compatible with representative democracy. There is no way to predict whether someone will do a good job as a president. Similarly the question asked in the brexit referendum was actually too complex for anyone to have a fact based answer. To know whether it is better for the UK to be in or out, you would have to predict what happens in both cases and compare the two. Which is impossible. So for people to make informed votes, the questions need to be very specific and fully specified. Conversely you can argue that direct democracy requires a system such as you describe to function. Otherwise people will tend to vote based on what the people they support say is correct. Which is pretty much the same as current system. Honestly the brexit referendum wasn't really about the EU, it was about which set of politicians you distrust more. So instead of a value add, I think it would be entirely new political system and the main effect would be total reformation of politics based on direct democracy. [Answer] I think if you want to filter people from the voting system, then you need to filter way before they can even reach a voting machine. The system you propose is defeatable. Just have voting booth with privacy and a smartphone. It's also very arbitrary and hard to control. If you are going to filter people, you need a filter that isn't discriminating. Filtering people based on whether they know something or not, or whether they had proper education or not, it's flimsy. A better filter could be civil/military service. You serve for X years, and you get the right to vote. You serve for Y more years, you get the right to be elected or access some higher unelected offices. That way, it's a right you earn. Anybody can earn it, but they can only earn it at a non-negligible personal cost (i.e. giving years of your life to the nation). Any idiot can read a pamphlet from a candidate that will give all the answers your machine expects, but to go through years of service takes proper motivation. It wouldn't be something taken for granted, it would be something earned, and something earned is less likely to be misused because of all the trouble you went through to earn it. Obviously, no system is perfect, this one included. [Answer] If you would have a political tests on the powers of the president it might have a question like: `Can the president start a war without approval of congress?` Constiutionally declaring war is the prerogative of congress but in practice US presidents do have the power to start war. A person creating the test could decide on what happens to be the right answer based on their own political beliefs. That means they can filter who's allowed to vote based on the political beliefs of the person. You can't have a test without a person writting the test. Thinking of the test being unbaised is like thinking of Supreme Court Justices being unbaised. The human element is always present and can't be simply removed. [Answer] Much shorter answer: The point of voting in a democracy is **not** to find the best choice on a ballot.\* The point of voting in a democracy is to prevent unrest and armed rebellion.\*\* --- \* Everyone can easily see countless examples where democracy lead to incredibly bad decisions, the most famous one being Germany in the thirties. \*\* The popular vote prevents a strong mismatch between the government and popular opinion, which is a necessary precondition for a revolt. The logical conclusion is that by restricting the right to vote of a large part of the populace, you negate the primary advantage of democracy and significantly increase the risk of a civil war. [Answer] In addition to important points raised by others ## There is risk in the questions Here's a quick set of [guidelines from a survey system provider](https://www.surveymonkey.com/blog/2015/02/11/5-common-survey-mistakes-ruin-your-data/) that explains a lot of what can go wrong. Though I'll give a couple of crude Brexit related examples. 1) How much have immigrants overwhelmed the local services in your area? 2) The EU invests £1000/person/year in your region, how much has this improved your area? There's no subtlety in either of these questions, it's possible to write deliberately leading questions with a lot more style, it's also easy to write leading questions by accident. If you sit people down and ask them a series of badly worded questions before allowing them to make a decision you can easily affect the outcome. [Answer] No, your proposed system would not provide any value added to the current democratic process, as it would promote certain ideals of political reason and further hinder political discussion within communities. Kuhl's answer is the start to an interesting discussion of political philosophy that has emerged in the current generation of the Frankfurt school of critical theorists. As reason cannot be conceived to be a universal (e.g. Hegel's critique), a literacy test is bound with a limited perception of reason (as no universal reason can be used for the creation of this test). Thus, limiting the voting population by such a test would, and has, lead to hegemony. The Frankfurt school's response to this was the concept of "communicative reason," which, in its simplest terms, is the reason that emerges when the personal histories (e.g. "leaving the European Union would affect my son's job") of citizens interact. From this, a conception of "deliberative" democracy has been formed. Thucydides's concept of deliberation within the market is beset by historical power relations (e.g. "slavery was at the foundation of American capitalism") and ignores a history of the critique of capital (Marx and those who follow his tradition). The "deliberative democracy" approach is that of creating centers of political discourse within communities (with panels of legislators and researchers for reference) to provide consensus on topics. There are many current debates on the precise methodology, but the core idea, I believe, is the key to the issue you've presented. Political communication and deliberation on the level of democratic constituents might not have prevented "Brexit," but would have allowed for a meaningful discussion, rather than political discord, to have come out of either decision. [Answer] Short answer to the question: no. Some excellent long answers already posted. One additional reason in practice rather than abstract is this. How do you keep the test questions secret? And how can you convince the electorate that the answers were not leaked to a select group to bias the result? I think it's a given that even if complete secrecy was indeed maintainted, somebody will claim otherwise! A better idea is to make voting slightly harder. I was opposed to the wider introduction of postal voting. Much better if voters are required to make themselves physically present at a polling station, or to apply in advance of *each* election giving reasons why physical presence is an unreasonable imposition. Historically medical infirmity attested by a doctor and pre-planned travel attested by an employer or hotel or transport bookings were accepted. If you did not vote that was regarded as precisely equivalent to "don't care" and willingness to abide by whatever result was obtained from the folks who did care. Some people live nearer to polling stations than others so maybe increase the time penalty slightly. Quirky, but if the system was such that you had to sit in the polling station for five minutes in silence with all electronic devices turned off before you could cast your vote, that would be an improvement. Also those five minutes might encourage reconsideration and responsible voting. I have done jury service. I hope that all juries are like the ones I was on and take plenty of time to consider before irrevocably deciding . The democratic voting system could enforce a pause for consideration and this could not be argued as a disguised attempt at gerrymandering. BTW I suspect I am in a smallish minority in this Twitter-obsessed world of instant gratification and knee - jerk reactions. So be it. [Answer] It will be **extremely** hard to agree on the questions, because such questions \*are already used\*\* to manipulate electorate - it is called [push polling](https://en.wikipedia.org/wiki/Push_poll) - wikipedia article has interesting examples. I agree, the only way to save the republican for of government from the mob rule is to regulate who can vote. But mob will not agree to vote themselves out of power. As quote attributed to Stalin says: It is not who votes, but who counts the votes. [Answer] This is a complicated issue. As others have noted, it is almost impossible to make an unbiased test. However, there is something else that should be considered: **democracy**. For example in Spain, general election was held a few days ago, and the party that won is well known for being involved in several corruption cases. Almost everyone who voted did know this. The problem is that this is the only party that defends certain interests that many Spaniards consider more important than having a non- corrupt government. The best way in which this test may be useful is check if people know the election program and past actions of the parties. The problem with this is that most people have no idea of these issues. So, only a minority will have the right to vote. [Answer] With the rules you set I'm assuming you also mean a perfect voting populous. Everyone who wants to can read and take the test, there is no bias in the information in the test, etc. I think it would have profound effects on some voting outcomes and do little for others. What would happen is certain votes would not happen at all. With full knowledge some candidates might not run on fear of the past coming into play. Referendums will never be put up because they simply promote a political agenda or meant to line pockets. [Answer] The effect of this can be modeled by vote cancellation to better demonstrate the effects that would occur. Instead of thinking of it as excluding some people from voting, permit everyone to vote, but have the testing system cast votes to negate the votes of those who were not qualified. In a 2 party system, this would just mean casting a vote for the other candidate. In other systems, the definition may be murkier. By describing the effects in that form, its quite easy to see that those who design the test effectively are being given extra votes. For every person that fails their test, those designers of the test effectively get a vote against them. Of course, the designers don't get to choose which candidate the vote goes towards. If the dumb person votes for Candidate A, and the test makers wanted Candidate A to win, the testing system still gives a vote to Candidate B. But now there's some substantial incentive to subjugate the system. Now there is a very strong interest in corrupting the test such that people who vote against the test-designer's opinions fail the test. That incentive can literally be measured in free votes given to the test-designers. Obviously you woudl need a panel to design these tests. But we haven't solved the problem. There is still a panel of individuals, and that panel has opinions about how the government should be run. That panel as a whole has now been given free votes! You could solve this by having everyone vote on what the test should look like, but if you think people aren't fit to vote on a political party, they're certainly not up for the challenge of voting on a test to control political parties! The panel has to be a subset of the community, and they are effectively given more votes than usual to counteract the votes of the stupid.... or votes of the minority. You could try to build a panel to control the panel, which would be a [turtles all the way down](https://en.wikipedia.org/wiki/Turtles_all_the_way_down) argument. Eventually the buck would land on one person who makes subtle decisions that shake the foundations of our government. We're buggered that the president, an elected official, will elect a bunch of judges to the supreme court. Think about how much power you're handing out now... your entire franchise! ]

[Question] [ How do you check if a room behind a door aboard a spaceship has an atmosphere and pressure? This is so that you would not accidentally open a door to a room which is open to space. I imagine there would be some sort of sensor on the door. However, this would probably require electric power. What if the ship has lost its power? How would a survivor check whether the other room has an atmosphere? Doors could have a window and there could be a cage with birds, so one might see whether the birds inside the room are alive. But this is not a very *scientific* way to go about this. What would be a more modern way to do this? Maybe some sort of chemical sticker (reacting with oxygen) on the window? [Answer] There's no need to start coming up with new science function stuff for this - real world designs are quite sufficient. Here is a door from the ISS: [](https://i.stack.imgur.com/BSsxc.jpg) If you zoom in on the image, you can probably make out the opening and closing instructions. Space stations doors are generally designed mechanically to not open if there's any significant pressure differential in either direction between the compartments. If the door would be designed to open even with a large pressure differential, opening a door against lower pressure would be impossible due to the force required to open the door against pressure (assuming door opens "inwards" as is customary). On the other hand, opening such a door against a higher pressure would be possibly catastrophic, due to the door swinging open with huge force. Instead, there's a manual pressure equalization valve on the door. You know, an adjustable hole, nothing fancier than that. (Black handle bottom right on the image.) Since life support is regenerative, simply opening a small hole to the next compartment is enough to slowly fill it - and when the pressure differential is small enough, the door can be opened. If the compartment has a leak in it, or is open to space - tough luck, there's no possibility of opening the door, short of cutting or exploding it open. [Answer] Take a leaf from early submarines. Specifically the inner torpedo tube doors which you do NOT want to open if there is pressure on the other side (A boat sinking flood sort of mistake)... There is all kinds of interlocking, but that requires power, the ultimate safety check is a small valve which you open before even thinking about undoing the dogs on the tube, if water comes out with considerable force behind it you probably think twice. A simple valve with a whistle arrangement would probably do it and needs no power (Interlock the valve so it has to be opened before you can spin the hatch wheel), but there are many simple pneumatic things you could run off a bar of pressure differential. [Answer] A passive system is really quite simple. Whether or not it becomes widespread is another issue. Put a thick flexible but strong membrane in the door. The membrane would bow into the suspect room if the pressure was lower. The degree that it bows in is the measure of the pressure difference. Like the lids on vacuum-sealed jars are pulled into (pushed into?) the jar as long as it is sealed tight. You also have to consider the direction the door swings. If it swings towards the room of high pressure and away from the vacuum, you would never be able to open it. If it swings in the direction of low pressure, it would spring open once the latch is released. If it slides, it would depend on how frictionless the door tracks were. [Answer] > > What would be more modern way to do this? Maybe some sort of chemical sticker (reacting with oxygen) on the window? > > > # A valve included in door (or wall) design The simplest way to do this would be to have a cylindrical hole drilled through the door or through the wall next to the door, with a valve in it: in section: ``` | +----------------------+ | | | +-----+ | | +-----------+ | | +---------+ +---------------------+ +------------------+ | | +---------------------+ +------------------+ +-----------+ | | +---------+ | | +--X--+ | | | +---Z-------X-----Z----+ | | interlock: when the two X's are | | aligned, the door can be opened | ``` You can have a spring mounted inside the chamber. If the pressure is equal on both sides, even in the dark, even with shipsuit gloves, even in microgravity, you'll still be able to move the valve end in and out slightly and *feel* it moving. If there's vacuum or overpressure on the other side, the valve will disappear inside or remain stuck outside, and chances are you won't be able to have it budge easily; again, this will be immediately apparent. Additionally, the valve ending could be shaped as a whistle, so that forcing it open would cause a piercing whistle to be heard. And the valve might be made large enough that forcing it open on purpose (which would, at that point, require considerable strength) would exhaust the atmosphere in a reasonable time. This is because you might happen to be trapped in a pressurised room, with your suit on, the power off, and unable to exit because *you can't open the door against the pressure*. Opening the valve would depressurise the room, freeing the door and allowing you to reach the escape pod or whatever (in a similar way, if you ever find yourself in a submerged car, you won't be able to open the doors against the pressure until the car is full of water, which might require opening the windows). You could also have, instead, a transparent window with two aneroid barometers at both ends, or devices such as a small sphere full of helium gas inside a pierced cylinder - it will float upwards in atmosphere, stay down in vacuum. But this kind of check looks more complicated and error-prone to me; in the case of the helium plunger, as Lenne observed, its operation also depends on there being gravity. One advantage of the mechanical nipple sticking out or being drawn in is that it can be easily used to both electrically and mechanically override the door lock, preventing it from opening unless pressure is equalized. Then you'd need an override to the override, but that's engineering for you. **Fancier but less robust design** Same as above, but now the plunger (which will probably need to be larger) is also connected to a moving arm or gear, rotating a circular sign disk inside an armored glass window - sort of those toilette signs saying "OCCUPIED". The sign would be divided in three equal slices saying 'PRESSURE', 'NORMAL' and 'VACUUM' on both sides, with the two faces mirrors of one another and aligned on 'NORMAL'. Only one third of the circle would be visible through the window, and normally it would read NORMAL on both sides when the plunger is in the middle (you get the idea). # Emergency tests (for doors with no vacuum check valve) So you're left in front of this door which you want to open to go on, but - what if there's no air on the other side? The door is not equipped with the valve described above. What can one do? **Door structure**: check that the door is not bulging inwards or outwards. If it is not, chances are that it's too thick and rigid for Heikki Mäenpää's "knock test" to be conclusive, but -- try knocking all the same. **Noises**: hisses would be strong indicators of a significant pressure differential (and an imperfect seal, which is bad in its own way). Also, if there's significant background noise, perhaps it is possible to check whether there are any of those background noises coming from the other side of the door. If there are, there must be air to transmit them. **Window observation**: check on the other side with a strong light. Sharp shadows *from a point source* are indications of possible vacuum (warning: the Sun or an illuminated room are definitely *not* a point source). Dust motes are an almost sure indicator of atmosphere, but there are phenomenons (see Hal Clement's *Dust Rag*) which might mimic that. Moving shreds of papers etc. would also be telltales of there being an atmosphere. Evidence of explosive decompression would likely indicate there is no atmosphere anymore. **Temperature**: if the room beyond the door was full of air and this got out, the lowering pressure should have led to quite a detectable drop in temperature. Then, vacuum being a very good insulator, things would have remained cold. This can be seen in the infrared, or maybe by touching the door and walls until they get heated from the pressurised side. Also, heating one side of the door would give different results if the other side is in vacuum or not. A likely popular rule of thumb would be **if you're not certain that there is an atmosphere, treat it as if it was a vacuum**. [Answer] Knock on the door. ~~If someone answers it, it's probably not open to space~~ If it sounds hollow, there's atmosphere to resonate inside the compartment. If it sounds solid, the compartment is open to space. I happened to have a small, thick-walled plastic bottle at hand to test this hypothesis, and I could sort of hear the difference. [Answer] A simple pressure gauge between the two rooms would be fairly easy to arrange and would not need to rely on electricity. There are many types of mechanical gauge for example: <http://www.madehow.com/Volume-1/Pressure-Gauge.html> But other sorts are possible such as a mercury manometer such as this: [](https://i.stack.imgur.com/0xbmH.gif) The red band is Mercury. If one end of the u tube was connected to one compartment and the other end was connected to the adjacent compartment then the pressure difference could be easily seen by looking at the tube. It would also be possible to include micro fine porous materials to allow the passage of air but prevent Mercury vapour from escaping into either compartment. [Answer] Pressure gauges have already been mentioned, along with several simple mechanisms to achieve this. If you want a real-world example (I work in a facility where rooms are kept under negative pressure) you would use something like a [Magnehelic](http://www.dwyer-inst.co.uk/Product/Pressure/DifferentialPressure/Gages/Series2000). This is based on the rubber diaphragm concept mentioned in another answer, but linked via a leaf spring to a dial for easy reading. The mechanism is purely mechanical, has few moving parts, is cheap and doesn't depend on gravity. The site also mentions that it works with a vacuum, although we use it for smaller pressure differentials. > > this is not a very scientific way to go about this. > > > I work at a national research centre and this is the solution used in a recently-constructed facility, so can confirm this is a modern solution used by actual scientists ;) [](https://i.stack.imgur.com/c9x8D.gif) [](https://i.stack.imgur.com/S7XHK.jpg) [Answer] Real world example. In medical contexts you often want low pressure rooms (often called negative pressure) for patients with infectious airborne diseases like flu or tuberculosis so that air will flow into the room and not escape with the infectious particles. Not perfect, but just one part of an infection control plan. Anyways, these are hard to maintain and often break down so they have a [clear plastic cylinder poking through the wall with a red ball inside](http://airflowdirection.com/web-n-72.jpg). The cylinder is on its side with a slight incline down towards the higher pressure side. There's a small vent hole at each end. The negative pressure side has to be low pressure enough to suck the ball up the slope and into that side of the room. The ball then covers the vent hole. If you see the red ball on your side it means the other side is at close to equal or higher pressure. [Answer] ## The door just won’t open If you've ever reopened a refrigerator right after you closed it, you know a tiny pressure differential makes a big difference on opening a door. Like the fridge, pulling a door toward you against a lower pressure outside will be simply impossible. That direction is easy. How about the other direction? If you've ever done rope/cable/chain rigging with couplings, you know that it's quite hard to unlook a line that is under load. Most couplings either require that you unload them entirely and slack the lines (like a carabiner), or the mechanism binds *very hard* so as to make it impracticable without "taking a wrench to it". Apply the same design principles to a door under pressure. Include an over-center mechanism or other arrangement. And then tune the length of levers and the ratio of gearing so it's very hard to open against atmo; consider this "good UI design". Of course you must also help people distinguish between atmo on the other side of that door vs the door binding from damage. That is easy since atmo is *bouncy* and binding is not. [Answer] As a combination of two previous ideas, and addressing potential issues with each one (but possibly creating new issues), consider two clear tubes, one twice the diameter of the other, and connected to form a loop which passes through the door or a nearby wall Each tube contains a ball fitting snugly but able to move without requiring significant force. The smaller ball is easily identified by size, and may be coloured or made fluorescent to aid in telling it apart from its partner. It serves as the warning for vacuum on the other side. They are connected by a cable or cord forming a loop, so that regardless of the direction, pulling or pushing one ball will cause the other to move at the same time and by the same distance. The balls are not permitted to quite reach the changeover point between tube sizes. Small vents are placed across the changeover point on both sides of the door/wall. When one side is vacuum and the other pressured, the greater area of the large ball is experiencing four times the force of the small ball (radius-squared of a circular cross-section) and a net force of three times the force on the small ball pushing the large ball into the side with vacuum. The cord pulls the small ball into sight on the side with atmosphere, showing vacuum on the other. A simple additional elastic band in the larger tube pulls the large ball into the middle when the two sides are equivalent pressure. The design is somewhat roughly shown below. [](https://i.stack.imgur.com/4OTvJ.jpg) [Answer] It would be very easy to have an indicator in the window or door that raises a flag any time the pressure on one side changes. Some sort of membrane perhaps, that would move away from your room if the other room was depressurised. I'm pretty certain something like this is used on aeroplane doors... It may be physical or electronic. [Answer] **Have the door open out** As in, you have to pull the door to open. If there is no pressure on the other side, you won't be able to / it will be very difficult to open the door, or you'll be able to open it a little before it's quickly sucked closed again. [Answer] People have mentioned pressure sensors already, and I want to reiterate that with a real-world example of using such a device, off-the-shelf in a spacecraft. Skydivers frequently [wear mechanical ANEROID BAROMETERS on their hands](https://www.venture25.co.nz/ic/1231990097/Sapphire.1.jpg); they read pressure out with a rotating dial indicator, like a clock-hand. It would be simple for anyone making a space door to change their output gearing and indicator face to rescale to a different range. (Felix Baumgartner [took one to over 127,000 ft altitude](http://i.huffpost.com/gen/807661/thumbs/o-FEARLESS-FELIX-570.jpg), so I assume they are compatible with vacuum.) One model, the "Altimaster Galaxy", is $169 retail. The door could contain a pocket or cell in the door in which one of these could sit, open to the outside and having a transparent viewport to the inside. The pocket or cell could use a sufficiently small commutation tube to protect it from abrupt changes in pressure, as well. Here you can see a wrist-mount aneroid barometer used as a cockpit instrument, mounted in the upper left corner of this picture inside the White Knight aircraft, whose cockpit was [designed to match](http://www.scaled.com/projects/tierone/) SpaceShipOne's cockpit for training reasons. [](https://i.stack.imgur.com/CsEpY.jpg) A similar device (this time on the upper right of the dash) is visible in this picture of SpaceShipOne in microgravity flight [at the edge of space](https://www.youtube.com/watch?v=29uQ6fjEozI); judging from the pilot having no gloves covering his hands, notes that SpaceShipOne [was intended to be sea-level-pressurized](https://en.wikipedia.org/wiki/SpaceShipOne#Design_goal) (and White Knight [the same - to unlimited altitude](http://www.scaled.com/projects/tierone/)), and the assumption that unpressurized craft cannot go into space with people aboard wearing no gloves, I assume they cannot be using this as an air-pressure altimeter and are instead using it to verify correct/ongoing cabin pressurization. Visually, it does not appear they changed the gearing or face of the aneroid barometer / pressure altimeter at all before using it. (And you can see the empty wrist-mount strap slots on it.) [](https://i.stack.imgur.com/1IV4F.jpg) So, one of these altimeters (aneroid barometers) mounted on each side of the door you want to check for pressurized atmosphere and visible through the door would do the trick, without any other design impact on the door, its opening mechanism, power requirements, etc.. [Answer] As I said in the comments, odds are that if you've survived depressurisation, you're probably in a survival suit and aren't too worried about the atmospheric status of any given room. Be that as it may, my suggestion for visible room monitoring would be a dye capsule of some sort that bursts when the room is exposed to vacuum. This capsule would be next to (or even in) the door, in a pressure safe vestibule exposed to the room behind the door, but not the corridor beyond (there would be another in the other side of the door to indicate the status of the corridor for those in the room), this capsule would burst and stain the indicator window when exposed to vacuum giving a quick warning. Dye colour would of course depend on the species and their particular safety protocols and colour sensitivities. [Answer] In the first season of Dark Matter, they had a situation just like this. Here, one1 of the main characters simply felt the temperature and based on the fact that it felt cold, concluded that there was space on the other side of the door. To me, it seems rather plausible that a bulkhead or a door functioning as a bulkhead, does the bare minimum to keep the insides warm enough, while the hull is built for comfort as well. As such, a difference in temperature seems like a good indicator to me. 1: As an added bonus, this wasn't just one of the main characters. It was One of the main characters. It was One. Yep, a guy named One. [Answer] Temperature gauges on the doors. In vacuum no particles means no heat transfer. If windows all the better. I would think bulk heads and airlocks have a door locking mechanism that locks shut toward depressurization like an inner tube stop leak gel, it has a ledge inside the door jam that gets pulled toward the vacuum and seals the doors. I would also imagine you could check the doors with your sophisticated temperature gauge known as your hand. If you feel a difference from the door material temp to a different wall and it is of the same material it should tell you a lot about the atmosphere of the next room. [Answer] *(The only solution that does not require the door to already contain a special device)* So you are the only survivor, there is no electricity, the normal safety devices are out of order, and the door is a Soviet era 100% aluminum door with no fancy features whatsoever. It looks like you have no way to find out whether the other side of the door is outer space, or on the opposite still contains the oxygen you need. ... until you find that battery-powered [thermal imaging camera](https://en.wikipedia.org/wiki/Thermal_imaging_camera), brought by the Korean team to study [insulation](https://en.wikipedia.org/wiki/Thermal_insulation) in space. Just point the camera at the door, and check the color of the door's outer frame: * Red (or similar to other parts of the room): you can open. * Blue: Only open if you want to get a taste of outer space's [−270.45 °C](https://en.wikipedia.org/wiki/Outer_space) temperature. [](https://i.stack.imgur.com/rD8L2m.jpg) [](https://i.stack.imgur.com/VuITUm.jpg) [Answer] **"Everything should be made as simple as possible, but not simpler."** - *Albert Einstein* *Uh Oh*! Reading back through the posts, it seems that ***Jasper*** had the same idea and posted it before me. **DENIED!!!** Try placing the uncovered palm of one hand against the bulkhead near the door or across the aisle. Place the uncovered palm of the other hand against the door itself. If there is a significant difference in temperature, don't open it as the odds are high that it's both depressurized and atmosphere challenged. It's like checking for a fire behind a closed door, only colder. If the temperatures are close, then it's probably okay to open it as it probably has both atmosphere and pressure since you wouldn't keep such a room heated to match it's surroundings. If that fails, call either Spock or Scotty -- one of them will know the answer. [Answer] Each side of the door has its own tube which initially is parallel to the floor, penetrating almost halfway into the door, then bending upwards and widening slightly. The vertical portions of each tube are visible via glass plates on the opposing side of the door. The plates are not looking at the same tube - each side has an opposing tube. In the vertical portion, a ball either floats or not. if the other side of the door is vacuum, the ball is not floating and is probably not visible through the plate. If the other side has pressure, then it is that pressure that floats the ball, making it visible. Purely mechanical, requires no power and has no sensitive, fragile, interconnected moving parts. Just a tube with a ball in it times 2. [Answer] **Light diffraction** No atmosphere means no particles to diffract light in the depressurized chamber. Sharp shadows could be an indicator. [Answer] A simple solution is a diaphragm that keeps the door latched if it's bent 'too much' either way. (And also displays this fact somehow. You have to be careful, though, as the diaphragm itself can be a source of leaks. Ditto, what happens if the mechanism jams? [Answer] I would reccomend jamming a screwdriver in the door. If you hear the distinct sound of wind, followed by your ears exploding, there is likely a vacuum on the other side of the door relative to you. Remove the screwdriver and act accordingly [Answer] I would recommend something primitive. Such as a bellows, where the pressure difference depresses a sensor effect (or just closes a switch). That then powers red LEDs that say vacuum. Pluses to this system: It doesn't need to be manually operated. It is red. I like red. ]

[Question] [ Note: this is an in-universe explanation, not media in general. Media in general tends to have magic written in archaic, usually dead, languages. In my world, magic is best described as fickle; most known spells are "iffy" with many having unintended consequences. For example, a spell to cure a lame limb might also turn it ghostly pale or a spell to cure one's cow might cause it to also grow another tail. The spells themselves are written on tablets, scrolls, etc., passed down from generation to generation within the 'Mage Families'- people who bought spells in the market, happened upon an ancient library or wizard's tower, or accumulated them over the years. While new copies of spells can be made, only a few select spells are seen as worth copying due to them having been used enough times to have a clear outcome and side effects. However, the spells can only work if they are transcribed exactly as written, which means writing in the ancient "Magic Languages". What would be a good in-universe justification for the "Magic Languages" to be a series of dead languages while contemporary languages are unable to have any ability to make spells work? Note: by dead language I mean no one speaks it as their native language, and the Mages themselves have a very minimal understanding of it. In this world dreaming is a very important part of the Theology so tying in dreaming would be nice, but isn't necessary. Brand new spells are very, very, very hard to create with only a few being made every hundred years or so. However, finding new spells is rather common. [Answer] # Immutability A language is dead if it is no longer in current use. One of the effects of nobody using the language anymore is that it doesn't change. Consider latin, for example. A *tersorium* is a collective hygiene device. There are no more romans around, so you can be sure that unless there is a revival, one hundred years from now a *tersorium* will still be a stick you use to clean your butt. English, though, is the current *lingua franca* of the modern world. It changes all the time. It used to be that: * **nice** meant stupid; * **gay** meant joyful; * **boners** were honest mistakes; * **thongs** were sandals; You totally don't want to botch a spell because something changed meaning. Imagine trying to solve a drought on a poor third world country and then all of a sudden datacenters are falling from the skies on the poor villagers. # All magic is performed by genies You may think that you have mastered all secrets arcane and ineffable, and that you are able to bend and rend the very fabric of reality. In reality, magic is a lot like programming. The computers are invisible astral creatures that have been around for a long, long time - and they were created by the very same people whose language is now dead. That's why they only understand sentences in those languages. [Answer] ## Your Dead Language is a Programming Language The speech of modern folk is merely meant to communicate with one another, but the ancient tongue is a programming language that directly shapes reality. An accidental slip of the tongue could be catastrophic for both the utterer and those nearby. Therefore even in the days when it was well known, it was seldom spoke. Each successive generation learned less and less of the ancient tongue until we arrive in the present wherein the more esteemed mage families have managed to preserve different bits and pieces which have come to be associated with them. Additionally, much of the written works of the ancient ones were scribed in their signature language, but the surviving works are treated with caution as there seems to be no one who fully comprehends what the utterance of those words would invoke. As a bonus, you asked if dreaming could somehow be connected to the magic here. There's actually an excellent opportunity for that. See, dreamers enter a non-material plane during their slumber wherein consequences are typically less severe (yet consequences still exist, often in another form). Practicing magic here requires practice in attaining more lucid dreams as well as remembering the words to be practiced in the first place. The ancient ones understood this and that is how the language was originally kept alive, but that practice has long since died out. Now, few people are even aware of that possibility and fewer yet are capable of such a task. [Answer] ## Because they're the original spells and no translation could ever get it right. As an example of a holy book, the Torah (the first 5 books of the Bible) is written in Hebrew and will always be written in Hebrew. The same ancient version of Hebrew it was first written in thousands of years ago. When you create a new Torah scroll, you copy each letter exactly. It must be done by someone not just pious but highly trained. Then it's checked. A single mistake (if it can't be scraped clean off the parchment) means the entire panel is no good and must be started over. Of course the Torah exists translated into pretty much every language on Earth. The entire Bible does. You can get meaning from it in English, Swahili, etc. But if you're going to study it, if you care about the precise wording, you must study it in Hebrew (not just any Hebrew, but Biblical Hebrew). While there are some very specific prayers, some magical incantations, and also puns, numerology, and shared roots in the Hebrew, this is a holy text and not a spellbook. Still, sticking with the exact original wording is vital. New prayers can be in any language, but they're usually also in Hebrew, to match the Torah. Usually with phrases taken from the larger Bible. The individual words and phrses have specific meaning that can not be translated 100%. (Note: I'm only talking about Judaism; other religions that have used our Bible have different language uses.) If real-life holy books need this level of language precision, then a book with magical spells would need it even more so. Some words translate easily (a cow in English is probably exactly the same as a cow in Aramaic) but most have subtle differences. Any difference can doom a spell to failure (or disaster). [Answer] **You don't use dead languages in casual conversation.** That's what makes them *dead*, after all. Sure, you might casually drop a smidge of Latin into your diction, but usually only a little and in distinct fixed phrases. We can talk about an *ad hoc* solution or the like, but we don't inflect or twist these phrases in our day-to-day lives the way that a native speaker might. This is good, because if your words are magic, they're dangerous. Say I have a fire spell, and I associate it with the plain English word "fire". Then I'm watching a baseball game with my friend and I say "the White Sox pitching is really on fire tonight" (this is a crazy parallel universe after all). If I'm not careful to prevent my spell going off, suddenly that might be more literal. Or it might be my TV that's on fire, or me. These are Bad Things. It's safer if the keywords for my spells aren't words I'm likely to use... well, *ever* would be ideal. Rarely used is less ideal but still way better than a word that I use casually on a day-to-day basis. This way the risk of it being accidentally triggered is lessened, and I'm more likely to perceive the need to stop it from happening ahead of time. (If I cast spells in Latin and I'm in Latin class, at least I know enough to read through ahead of time and spot any problems.) [Answer] **The *Language of Magic* (LoM) is useless for almost anything else** 1. LoM deals with more sounds than "modern" languages do. This is because in the case of magic, sound carries with it emotion, intent, expectation, and many other difficult-to-express with definable words than today's languages. The consequence is that rather than having the scant 52 characters of modern *Auquoric,* LoM has 421 unique sounds, each demanding an unique character.1 2. LoM is *precise.* It makes the grammatical gymnastics of modern *Fleurt* look like a day in the park. Verbs can be conjugated hundreds of ways, nouns can be declined hundreds of ways, verbs and nouns can be converted to verbs and nouns (etc.), and don't even ask about *gerunds.*2 Half of the reason LoM even still exists is that there are a handful of lawyers who *insist* that their contracts are written in it to guarantee no misinterpretation. It's so complicated a language that there are a rare handful of people who spend their entire lives simply translating it — and they often translate whole pages into single sentences of *Fleurt.*3 3. Not surprisingly, LoM takes a honking long time to say *anything.* Remember those Ents from *The Lord of the Rings?* Oh, yeah... they'd be long dead before a poem of any credible length could be verbalized. What's the point of asking your friend if she can hang out at the mall with you if, by the time you're done asking, the mall's closed? 4. To add insult to injury, magic isn't all that uncommon. And you'd have been surprised by how much damage was caused by little Jimmy Snydectoodle when he was showing off just a bit of a butterfly charm and suddenly sneezed. The little snot has a tendency to be infuriatingly vociferous when he does it, too! Old Lady Henschot still passes out whenever anybody mentions Doc. Crewlon's cow. Not surprisingly, quite a little superstition has grown up over even muttering something that sounds like LoM. You'd be just as surprised how many ways you can express the idea of "if you do this, you'll get the beat-down of your life" with fairies. 5. The subtleties of LoM are such that it requires the listener to actually concentrate when they're listening to people they don't like very much. Remember: sonically and lexically complex, and long-winded to boot. If you pay enough attention to that pond scum to actually understand what he's saying, he might think you were his friend! To make a long story short, people are intrinsically lazy and will rarely use a complex language if a simpler solution exists.4 6. It's simply impractical. Have you ever tried to tell your husband what groceries to pick up over the phone in LoM? You could turn your mother-in-law into a newt! Which isn't actually a *bad thing,* per-se, but "significant others" tend to get significantly bent out of shape over things like that. 7. Finally — it's lost. Considering how irritatingly complex LoM is, it's little wonder that most of it is lost. There's a handful of books written in it and a primer or two, but nowhere near enough to actually study the language — unless you're one of the lucky few who have been initiated into the School of Magic5 where a few Master Wizards jealously guard the few remaining Tomes of Arcane Knowledge.6 --- 1 *Hiccups or stuttering is a **really bad thing** when it comes to spells. It quite literally can mean your client, rather than being fabulous, is instead flatulent.* 2 *I speak Finnish, and Finnish is quite a bit like this. A friend of mine and I once spent a couple of hours calculating how many ways a single noun could be converted grammatically into another word or meaning. I kid you not, we stopped at 250,000. It's a wondrously complex language, and just to slap the rest of humanity in the face, it's absolutely beautiful to listen to. So many vowels!* 3 *If you don't think this is possible, you haven't read anything by Fyodor Dostoyevsky.* 4 *Think about the development of [Hiragana](https://www.freejapaneselessons.com/lesson01.cfm), Kanji and Katakana — but for completely insouciant reasons.* 5 *And the School of Lawyers... but they're really closed-lipped about the whole thing. It's amazing what a jealous wizard can do to an attorney's little finger.* 6 *And a good thing, too. Can you imagine what Jimmy Snydectoodle could have done to Doc Crewlon's cow if the little punk actually **knew** anything about LoM?* [Answer] ## The more a spell is used, the more reliable it becomes. At its core, magic is powered by belief. A family spirit can mature into a god as it gains followers, a mundane artifact may acquire magical properties as it grows older and becomes associated with good luck, a mysterious forest grove may become a Place of Power if it is regularly used to commune with the spirit world. The same is true of rituals, whether they involve magic circles, runes, or verbal spells. Most common spells were created when the now-dead languages were in use, and the more they are used the more people *believe* in their power - which is what *gives* them their power in the first place. It isn't that people *can't* write spells in new languages, but why reinvent the wheel? If the ancient word for *fire*, combined with a particular wand motion, became the ritual for creating a fireball 3,000 years ago, every time that spell is used it reinforces the *belief* that the particular ritual has that particular effect and therefore makes it more potent and reliable. Magic being the fickle, unpredictable thing it is, you're going to want the spell's effect to be as reliable as possible. Spells may be created on occasion, but how much is *really* new? Most "new" spells are just combinations of old ones and will still benefit from the belief in those older spells. So the ancient language will continue to be used by the magic community long after falling out of common use. [Answer] **Magic Kills.** Societies that developed magic eventually destroy themselves, so what is left behind ? The left-overs of their highly developed (but highly dangerous) magic. And what language will that be in : the language they developed. But need that language be real. In many fields we develop specialist language that becomes almost a language unto itself. The military often have their own ways of communicating for speed and accuracy. Lawyers use Latin quite a bit, as do many aspects of medicine and science. Expressions in specialist uses hardly relate at all to their everyday meanings. So the old texts and documents that the lost (destroyed ?) race developed their magic in may seem like an old language, but it's possibly more akin to a specialist offshoot of a real language. But magic comes with a price. As it is developed the forces become greater and the power it yields, both in physical and political terms, becomes enormous. Eventually there will be a war and little left behind. What records survive are mere shadows of what was possible - the equivalent, let's say, of Newton's Laws with the magical discoveries of more sophisticated rules left. And the societies that are left after the magic powered wars don't encourage magic, so it's hidden away. A cult, a family secret. Eventually the meaning and true scope are lost and all that remains are the dead language. But societies forget and when they take up magic again, they see only the power and not the danger ... > > What would be a good in universe justification for the "Magic Languages" to be a series of dead languages while contemporary languages are unable to have any ability to make spells work? > > > So in this scenario magic languages hide the "structure" of magic which the ancients understood. The vocabulary is lost and the number of samples (spells) known is too few (and too closely kept and secret) to be used to reform the required language. And some of those sounds made are e.g. complex names buried in a complex grammar that is context sensitive. Maybe making these sounds hurts and requires extensive training (and a willingness to suffer). And what are the names ? Maybe they're Gods, maybe something worse, maybe not so friendly. Perhaps the names are whole spells. > > In this world dreaming is a very important part of the Theology so tying in dreaming would be nice, but not necessary. > > > Dreaming, when your mind is open to connect to the magic realms, perhaps. When the ordinary "safeguards" that keep you bound within the walls of common sense are weaker or gone and ... something ... can make contact. But "they" aren't human and don't speak human languages or have human thoughts to share, so what you get in dreams are images which you try to interpret. > > Brand new spells are very, very, very hard to create with only a few being made every hundred years or so. However finding new spells is rather common > > > Sort of a contradiction there. I presume this to mean finding "new" (meaning lost) spells is common, but creating them from scratch is hard. Let us say we must find the whole spell (name ?) exactly and perform it correctly to connect with the source of the spell's power. Are we activating a machine ? A God ? An angel ? Who knows. We don't know what we're doing and we can't just accidentally come across the names of these ... things. Sometimes, rarely, people make a lucky guess. Maybe, as many early scientists did, they get it right but for the wrong reasons. They mix up words from different spells and, by accident more than design, they hit something useful. But most of it is nonsense. > > In my world magic is best described as fickle most known spells are "iffy" with many having unintended consequences. For example: a spell to cure a lame limb might also turn it ghostly pale. Or a spell to cure one's cow might cause it to also grow another tail. > > > The Terry Pratchett school of magic ! OK, this is applying a cost to using it. But this also plays into the idea that eventually magic kills your society. People are curious and they don't ever seem to stop trying to find out more (at least some of them). Magic may come at a price, but it brings power. Power brings ambition and greed. Eventually a society simply steps into far too dangerous a new "level" of magic and perhaps even the act of discovery is death, not merely to the practitioner, but to the whole race ? Perhaps the spell ("name") you uncover is one that does not want to be found. Magic - it's even more dangerous than Physics. :-) [Answer] Magic spells are actually a set of instructions to more-or-less intelligent entities - demons, elementals, or whatever you want to call them. These entities are very long-lived, and not really good at learning new languages. Like humans, there's a period in their "childhood" in which they acquire language natively. After that period ends, language learning is much more difficult for them than for the average human. The bottom line is that most of these entities learned Latin, classical Greek, or some other dead language, and only understand that language. Obviously, therefore, any communication with them must be in the "dead" language. As an amusing corrolary, there are some entities who only understand REALLY dead languages, like Etruscan or proto-IndoEuropean. And of course the older an entity, the more powerful. You might find a youngster that understands Shakespearian English, but it'd be outclassed by an Old English-speaking one, and both would be outdone by Latin, Greek, or Egyptian-speakers. [Answer] You do not want the magic to happen when you speak your daily speech. Let's make some assumptions: 1. Magic is ingrained in the fabric of reality, and reacts to specific spoken commands. 2. Based on #1, everyone who can speak the words correctly, can do magic. 3. You do not want to accidentally set people on fire. Imagine that the common magic language is English, and the word "Fire" actually sets the thing you're looking at on fire. Now a fire breaks out, so you look at your colleague, and shout "Fire! The house is on... oh crap!" You just roasted an innocent person. By using a language that does not map into anything normally spoken, you avoid the inconvenience of magic triggering at wrong times. Please educate your children on dangers of speaking nonsense made-up words, as that could hurt or kill someone. [Answer] Language drift causes meanings to be lost. An example is comparing the English language of Shakespeare to modern English. In just 500 years there have been subtle shifts in pronunciation, whereby people who have tried to recreate Shakespeare in "original Pronunciation" have rediscovered jokes and puns that Shakespeare had written for audiences to enjoy but which modern audiences have no idea are even there. [What Shakespeare's English Sounded Like - and how we know (YouTube Video)](https://www.youtube.com/watch?v=WeW1eV7Oc5A) Even deeper in the past, we have ancient Greek. Homer's Iliad and Odyssey were composed so far back in the past, the "W" sound had actually vanished from then modern Greek when it was transcribed. We only know this if we are reading or listening to it in Ancient Greek-some lines actually don't rhyme because the sound is missing. So using very exact original pronunciations and language ensures the meanings that power the spells are preserved, including hidden meanings that (when the spell was composed) might need the understanding of an initiate to decipher. How well rote learning of spells in a dead language works could be the subject of debate. If you actually don't know, recognize or understand the hidden meanings in a spell, will it actually work? Or is the lack of understanding the real reasons spells seem unpredictable these days? [Answer] ## The Ancient Language was Pulled From the Dream World by the Gods Like Prometheus, Odin hung himself from a tree (or in some cases sacrificed an eye) to find the runic language in a dream. Thoth invented the language of magic in Egypt, but Thoth did not do such things by himself, rather he worked as the scribe of greater gods, following them on their daily activities, and writing the 42 books that contained all knowledge that humanity required. He then delivered the knowledge either directly, or secretly through his wife (stories vary) to humanity. It may be that, likewise, the "good" languages for magic have a connection where some hero (or deity) wrested the language from the dream. [Answer] I think I'd go the other way and have the explanation for modern language be sequences of sounds and letters that have been discovered to be safe. You could add in a chaotic "Dark Ages" where people used to accidentally blow heads off and turn limbs into snakes all the time, until 'safe' sounds were discovered. Once a working safe languages quickly spread the globe, and there are only rare samples of the more interesting phrases that survived. [Answer] # Magic is instantiated by translation Familiarity breeds contempt. Well, really what happens, is when your brain is familiar with a language, it goes straight from conceptual reification in your head to pronunciation, with little to no delay in between. Casting a spell requires a certain amount of mental gymnastics to solidify the reality altering creation of aspell, and it's easiest to enact these steps when you have to struggle a little with the translation. Basically it's that struggle in the middle of "knowing" and "saying" where the actual magic happens, and the better you know your language, the less struggle happens when you cast the spell. Eventually, with enough castings, you can learn to embody the struggle rather than focusing on the knowledge or pronunciation part, and some mages can even master casting as spell without speaking the words. On the flip side a mage that studies too hard can learn a language well enough that it impairs their ability to cast spells in that language leading to a sort of zen like situation where the more you learn a spell, and practice it, it becomes both easier and harder to cast at the same time. You need intent without foreknowledge, a lovely little catch-22 that only the most masterful wizards can overcome. [Answer] ## Words-meaning combinations cause magic to *cure* with time and usage. Languages change over time. Not only that but it changes fairly quickly, listen to old english (which is, in the span of human history, still *new*) and you'll be hard pressed to understand it. Magic flows into the world through our words, and when a new word (with its meaning) is uttered it punches a hole in the barrier between reality and the realm of magic. The more it is used the larger that hole becomes, and there is a minimum threshold that people need to effectively use it in a spell. The commonness of words we speak today are still newborn and fledgling in the magic they can pull, much too small for our uses. Dead languages though, they had been used for generations. The gap they have made is substantial. A merely *old* word for fire may cause something to just barely feel warm to the touch. A word for fire that had come to mean heat and life for a hundred generations has gained the traction to combust brilliantly. ## Why age over quantity? When words, spoken not as spells, are uttered they flow through the same hole. It is not the usage of the word that expands this hole, but how long that hole had been used. The tapestry between reality and magic is infinite, so too are our words. As each spell invokes the dead language's meaning into pulling the arcane from that plane so too does it expand that hole ever so slightly. The tear gets infinitesimally bigger, as the fraction of all of time that it had taken up gets a bit bigger. The older the language, the better, but as language ever evolves so too is there a moving window of dead languages. Finding the oldest languages doesn't grant you insane magical abilities, you still have to have the capacity to pull from a large rift/hole/tear caused by the word. Equally, the words only tend to get to a certain size before the memory of it fades from existence and new words are created to replace it. As time flows ever onward, so too does the shifting language palate of magic. [Answer] **Thrice-cursed Muggles** All words are magic. Speaking a word makes use of some of that magic to convey the meaning to the recipient. If a wizard speaks the word, all is well. The wizard uses the word's power to convey meaning. At the same time, however, a word spoken by a wizard receives some of the wizard's magic and becomes magical itself - in total, the word gains magic. Muggles, however, do not have any innate magic. They use the word's magic to convey meaning, and so leave it a bit less magical. Enough muggles using the same word drains it of all its magic until it is about as useful for a spell as lint. (just try it yourself: repeat a word quickly and often enough, and it looses all meaning for a short time) Ancient languages like Latin have been dead long enough that there are more wizards speaking them than muggles, ergo they are gaining magic once again. However, if you want real power you need to broach into the more obscure languages like Sumerian, ancient Egyptian, or pure magical languages (if they exist) [Answer] The lost/dead languages may be the language of otherworldly beings which exist within dreams, or sleeping Gods whose dreams' intermingle with the dreams of mortals. It's not a language humans have ever used commonly, and all existence of it in this world comes sporadically from the brief contact made with these outsiders over the millennia through dreaming. What snippets of language that can be remembered after waking have been written down over the years. This is why there are no extensive writings in this language, why there's no record of a kingdom that once used it, and why no one speaks it and knowledge of it is so limited. The words are of dreams, and as such serve as a conduit from the dreaming world to the physical one. Just as dreams are confusing, unpredictable, and reality bending, the spells' effects too follow that form; hence the "iffy" and unintended consequences they bring. [Answer] # Magic requires a more mathematical style of language; modern languages lack the precision and structure required. Languages evolve to be practical; homonyms appear, shorthand and slang usually creep in overtime, misunderstandings and ambiguity are common place in speech. Magic is a complex practice, it requires careful balancing and fine manipulation of forces that are not even perceptible by normal means. Spells are like equations in physics, detailed highly codified descriptions of actual physical (or in this case metaphysical) forces that usually include an effect and what factors are involved and how they relate to each other. The lack of precision and potential for ambiguity in everyday language could be disastrous. We use mathematics as the **language** of physics for its rules and logical structure, lack of ambiguity as well as the detail that can be expression in a concise way, we don't tend to use everyday language. In the case of your world, an ancient civilization created and used a language with the same properties for expressing and describing magical forces, that mathematics has for expressing and describing physical forces, it has technical terms and linguistic rules which are capable of handling ideas and concepts that aren't even expressible in everyday language (because they describe concepts and forces outside the purely physical world). In fact you could also say that even this highly structured lingo isn't one hundred percent effective, tiny mistakes still creep into the formulae (rounding errors :D) and this explains the unexpected side effects of most spells. You could even have it that the actual technique of working magic is not that difficult, magical forces respond readily to the mind, however most people lack the clarity of thought and precision to produce any kind of effect by creating order out of the chaotic background interplay of forces. This conception of a magical language as analogous to mathematics means that spell books are essentially like mathematical proofs, the squiggles and sigils are formulae, the reason for old and powerful wizards having book filled towers (instead of just one book with spells) is because the theory and formulas are complex and hard to understand, reference works are essential to derive new formulas and spells. As for why the language is dead, a magical version of the Fermi paradox, a culture that develops a sophisticated powerful system of magic, has a chance of wiping itself out (wizard nuclear wars, accidental portal opening letting elder abominations in, very powerful spell goes very wrong and causes a catacylsm which wipes the society out). These are are all standard tropes of ancient magical societies. [Answer] The dead/ancient languages had a different basis and purpose than the more common modern languages. Modern languages are concerned with meaning, they serve to communicate about the mundane world and things directly experienceable by a person, feelings, ideas, concepts, etc. The ancient languages on the other hand were based on the sound vibrations they produced, they could also convey meaning, but in their essence, when correctly spoken, they "interacted" with reality (as in sound-waves interacting with matter, cymatics, etc). "In the beginning was the Word, and the Word was with God, and the Word was God." -> for a real world example of the idea. Some people say that specific languages like Sanskrit have "vibrational" properties. If you ever heard Buddhist Monks chanting you'll also notice (probably) that the sounds "reverberate" (although the words being spoken have a meaning as well). In a universe I'm currently writing what allows magic is the fact that the atmosphere is permeated by an element that reacts to mental activity (it all happens inside a simulation although in the story that's never disclosed or sufficiently hinted, and the people inside it don't know it either, but that's why it's possible) In your universe you could make it be that the produced sound along with the right focus, when correctly speaking those languages, interacted with matter. This would make magic very powerful and dangerous as well - it would involve not only the meaning of the words but also producing the "correct" sounds through your mouth and throat, setting your mind in the right context - usually requiring great deals of concentration - that's why spells could easily fizzle. Not because they're unstable but the correct "pronunciation" of the words, while keeping the right frame of mind, is very hard to do (it could also be a secret among the most powerful mages, that they learned it through trial and error for instance and noticed that different ways of "speaking" the same words would produce different effects and started taking notes on which worked well - still this would be naturally limited, some would die in their experiments and besides oral tradition there's really no way to convey exactly the right way that a sound has to sound). For the dream part. The fact that the "spells" are based on the vibrational characteristics makes it so that while dreaming the characters could "sense" that kind of sinestesia, between the words, their vibration and the right "context" of their mind for it to happen. This means they wouldn't need to become experts in the whole language to be able to cast a spell they "sensed" in a dream, rather because they experienced all those things (word, "pronunciation" and state of mind) in the dream they would be able to replicate the whole feeling of it - so dreams could inspire intuition on how to cast certain spells without making a character suddenly super boss of everything. [Answer] It's not the words themselves that are important, but the electrical impulses in the language center of the brain of the caster. Reading the dead language makes you say the correct set of things, making the correct set of impulses - knowing what the language means is completely unnecessary as long as you know how to pronounce it. Spells could be written in the non-dead languages, but as you mentioned writing new spells is hard as finding the sounds that cause the correct electrical impulses is difficult. This could be combined with some of the other answers suggestions that the dead languages were designed to help in memorizing the correct sound patterns to cause the correct electrical impulses, and also why the spells have other consequences - its hard enough to find a spell that gets a nearly right set of impulses. You could also have as a cool side effect that a character could discover a spell in a dead language - but not know exactly what it does as they can only translate parts of the spell. [Answer] Along a similar line of reasoning to what @JollyJoker suggested, maybe the ancient words were themselves 'enchanted' (much like you enchant ordinary objects, like the talismans you mentioned) by the race of people that happened to spoke the now-dead language to possess certain fundamental 'powers' or harness the power of an 'element'. You make spells by combining the 'enchantments' of the words but 'enchanting' new ones (in whatever language) is a lost art. [Answer] It work backwards. In the beginning, there was a word... and all words were powerful. But, people need words to communicate. New words are created, they carry only a meaning, but not a magic. The magic words are tabooed in order to avoid triggering unintended magic. The language evolves, the magic - not really. The world ends up with a language that is good to talk and has no magic in it. [Answer] # The magic is alive by itself Magic isn't so magic as everybody thinks. Maybe magic is produced by an omniscient entity, such God or the *weave*, or is produced by a collection of minor gods, spirits or demons. Those creatures hear the calling of wizards and perform the magical effects according to the set of instructions given by the spell incantation. Those primordial creatures exist from the beginning of time, and only speaks a single (now dead) language. That is why spells use that language, they use the language of the person who made it / who produce its effect. Maybe it's just a blessed language. During the time of creation, gods made this language and blessed it with magic, hiding power on each word. New, alive languages lack this blessing and so they can't be used to cast spells. # It isn't a language, but a collection of magical sounds and instructions It's told to be a language, but that isn't true. These words, or for being exactly sounds and written drawings had inherent magical properties. They're used to channel, unleash and command hidden sources of power from the very core of reality reprogramming the very laws of physic. Through a deep, large and precise research, wizards from all times have been collecting and cataloguing those sounds and symbols (or commands), carefully tailoring and crafting spell's incantations (or scripts). No one knows the meaning of those ancient words if they have one. The only current documentation we have are the spells itself, the rest was lost during the ages. # It's inherently magical Similar to both ideas above. Speaking in your every day with a magical language is extremely dangerous. You wouldn't like to accidentally unleash the anger of a thousand of demons or to change the fabric of reality with a single "Hi". # It isn't an spoken language but a mathematical or programming language Magic can't be done using such ambiguous languages as we use to speak. An incantation must always mean the same no matter the age or context. That is why the first wizards made an artificial language, a perfect template to make blueprints for new spells. Such annotation language is specifically designed to make spells, and so it's unspeakable for everyday uses. For example, programming languages are -like the name suggest- languages, but they are used to make programs, not to speak. You can make a program in Python or C#, but not speak your every day on it. Magic languages have the same effect, they are used to describe the behaviour of spells, not to talk. That is why no one can translate magic languages to normal speech and retain its power. You can turn a C# script into pseudocode or even plain English, but the compiler won't compile, as the spell won't be casted. # It requires an exact structure, pattern and meaning Compare: > > El árbol volador es verde y esta junto al río. Esta lloviendo. > > > With: > > The flying tree is green and it's next to the river. It's raining. > > > Look the differences, "árbol volador" is translated as "flying tree" instead of "tree flying". "El árbol" becomes "the tree", which lose the grammar genre. Both "es" and "esta" are turned into "is", which is context dependent. "It's raining" use a neutral pronoun, which doesn't exist on Spanish. All this slightly changes in meaning produce a hugely side effect on spells, which is too dangerous. # It helps mages to maintain focus Reciting a completely memorized incantation helps to maintain concentration. Reciting something in a language you know allows you to understand it and become distracted. Incantations don't mean anything, they are just techniques to help spellcasters to focus and channel energies. If you accidentally think in anything else, the spell may go wrong. That also explains why each spell has so different phrases, to avoid commit mistakes. # It requires a language that can't evolve Scientific use Latin to make scientific terms because it's a dead language. Since no society uses it on the present day, the language will never change. No collocations will be made not words will change their meaning. If you use a language which words changes over time (i.e: Any non-dead language) effects of spells will also change over time, which is something that everybody wants to avoid. Maybe the *hotness aura* of yesterday produces an insanely hot aura which burned everything, while today it produces an aura of extreme beauty. [Answer] ## It is the process of dying that makes languages magical When we as people die, so many of our secrets simply cease to exist. All that knowledge and information disappears, and much of it can never be recovered. When a language dies, when it *truly* dies, the same thing happens. The meanings of the words are gone from the world. Sure, we may be able to scrounge up enough ancient Egyptian texts and use the Rosetta stone to figure out what various blocks of text are trying to communicate, but because no one can be a native speaker/reader, no one really fully grasps the full meanings, and all the cultural weight and context behind them, the way an ancient Egyptian would. When a language dies, and all that meaning disappears from the world, it needs to go somewhere. And when a language ceases to mean anything to speakers, it starts to mean something to the universe. When magicians cast spells, they don't entirely grasp the meaning of what they say. They may figure out "hey, chanting this makes a fireball, and chanting that makes a fire go out, so this word probably means fire," but they don't know if it's a general word for fire, a word for a specific kind of fire, or if it means something entirely different that is somehow related to both fireballs and fire extinguishing. They are able to infer approximate meanings of words in order to invent/discover new spells, but they are never certain that their definitions are correct, and those definitions never come with an understanding of the connotations behind each word. Particularly skilled magicians may be able to create their own private languages, but those don't become magical until their inventors die, which makes it mostly a moot point. This becomes problematic if through some mechanism native speakers of the language are re-introduced to the world, whether through raising the dead or time travel. But the problems that arise from that might make for some even cooler aspects of your world. [Answer] **Why would “dead languages” be the only languages that spells could be written in?** Because they are **unchangeable, reach back towards the origins of things and are sacred** for those who pronounce such languages. We see this in languages are truly considered dead languages in the real world. > > A sacred language, "holy language" (in religious context) or liturgical language is any language that is cultivated and used primarily in religious service or for other religious reasons by people who speak another, primary language in their daily life. > > > Pali, Sanskrit, Chinese, and Tibetan are the main sacred languages of Buddhism. > > > Christian rites, rituals, and ceremonies are not celebrated in one single sacred language. The Churches which trace their origin to the Apostles continued to use the standard languages of the first few centuries AD. > > > Hinduism is traditionally considered to have Sanskrit as its principal liturgical language. Sanskrit is the language of the Vedas, Bhagavadgita, Puranas like Bhagavatam, the Upanishads, the Hindu epics like Ramayana and Mahabharata and various other liturgical texts such as the Sahasranama, Chamakam and Rudram. > > > Sanskrit is also the tongue of most Hindu rituals. It is an Indo-Aryan language and therefore a member of the Indo-European language family. It therefore has some similarities with Greek and Latin, as well as with many vernacular languages of Europe and south Asia. Like Latin and Greek, it also has secular literature along with its religious canon. Most Hindu theologians of later centuries continued to prefer to write in Sanskrit even when it was no longer spoken as a day-to-day language. > > > While Sanskrit has often been associated with Brahmanism, it remains as the only liturgical link language which connects the different strains of Hinduism that are present across India. The de facto position that Sanskrit enjoyed, as the principal language of Hinduism, enabled its survival not only in India but also in other areas where Hinduism thrived like South East Asia. Apart from Sanskrit, several Hindu spiritual works were composed in the various regional languages of India such as Hindi, Assamese, Bengali, Odia, Maithili, Telugu, Tamil, Kannada, Malayalam, Marathi and Tulu. > > > The core of the Hebrew Bible is written in Biblical Hebrew, referred to by some Jews as Lashon Hakodesh (לשון הקודש, "Language of Holiness"). Hebrew (and in the case of a few texts such as the Kaddish, Aramaic) remains the traditional language of Jewish religious services, although its usage today varies by denomination: Orthodox services are almost entirely in Hebrew, Reform services make more use of the national language and only use Hebrew for a few prayers and hymns, and Conservative services usually fall somewhere in between. Rabbinic Hebrew and Aramaic are used extensively by the Orthodox for writing religious texts. - [Sacred Languages](https://en.m.wikipedia.org/wiki/Sacred_language) > > > Sacred languages seem to all be [extinct languages](https://en.m.wikipedia.org/wiki/Lists_of_extinct_languages) to say the least including the Ancient Greek of the ancient gods of Olympia and the Old Norse and the culture of the Runes! Dead languages convey something of mystery and the unknown from which most of the population understands very little. For this reasons spells pronounced in such languages demand respect. [Answer] Magic is not only required to be spoken, it needs to be heard. A supernatural being understands every established language (or there is one being for every language), but it hears them all at the same time, hence all the voices casting spells in english cause none of the spells to be distinguished from everyday chatter. There is a hard limit on how many different voices can be heard and acted on. As a result only spells in dead and almost dead languages will result in a spell. [Answer] # Two models of 'where spells come from' An interesting question to ask of the collectively imagined meme of a spell or magical phrase is 'where did it come from?'. Why, for example, would a spell use human sounds? Why would it be made of the same phonemes we use in our speech? Why are all the magical words a bit like normal words, but not the same? I present two models, which might help with back story for this (and for a well-known book and movie series). The first is that spells are programmed in by master witches and wizards, to be shortcuts for others. The second is that they form a specific magical picture in the mind of the person casting, which ties to the universe's magical field. # A magical universal field Consider a spell where we have to hold a particular type of onion and utter the phrase 'Alliux!' to make someone we are picturing cry. In this model, the word itself would be essentially meaningless, but its purpose would be to recreate that particular thought from when we learnt this spell, for which the onion and the oniony phrase derived from allium (the family to which onions belong) serve as a mnemonic. This model would support the idea that you must cast the spell very carefully, that it requires practise, and that ideally someone taught it to you well so that you can recall the state of mind exactly. It would also require the person casting it to be magical, as the spell word by itself is arbitrary. Such a model might tie into dreams quite nicely; you might recreate some of those magical images in your sleep and accidentally cast them if you are having a fever dream, or are someone who sleepwalks. # Magic as a programming language with shortcuts In this model, there is essentially a magical field accessed via either a very magical person or creature or via a spell they have created. In this model, the spell word is very important, because it represents the way to access the shortcut. The spell creator might have made it a global spell, or spells could gradually diffuse out from a specific place. This would make it easy for non-magical people to invoke a spell, as long as they know the word. However, incorrectly invoking it if you aren't careful about the pronunciation, or if the invocation is complicated by requiring input parameters which are hard to simultaneously provide (e.g. it uses the thing you're holding or the name you think of, or any other contextual or mental parameter), then you may invoke it wrongly. The best spells (like the best code) would fail gracefully if they detect incorrect inputs, or require a validation step (you cast the spell and then do something to confirm it, or an enchanted vision appears to ask you). The worst spells would just take your dodgy input and carry on. This model has an excellent explanation for the words and language used for invocation; the invocation was chosen by the spell creator, and must not be accidentally spoken. So old spells would use old languages, or words similar to those in old languages. And foreign spells would use similarly foreign sounds. Mixing with people from a different heritage might permit you to learn their language, and some of their spells, if you could only make that glottal sound. In programming, one of the difficulties is invoking some code using an object you made elsewhere, i.e. combining one codebase with another. Even when very careful, this can cause lots of unintended side effects; the object doesn't have the expected properties or isn't set up in the way the code expected, so the code ends up in an unexpected state. This could be a useful mechanism for accidentally making cursed objects; an ancient Arabian oil lamp being used to invoke a European storage spell accidentally produces a one way tardis which sucks in anything that touches the spout until rubbed by a worthy child. Another particularly egregious problem could be that someone knows a privilege-escalation spell, and keeps making undisciplined people into spell-creators. They in turn keep making awful spells, polluting the vocabulary of normal speech with accidental invocations. People who lived near such a historically cursed place would have a huge range of shibboleths and unutterables, whole sound groups to be avoided for fear of unleashing irritating spells. The best spells would in fact be hard to conjure, requiring very specific invocation with very specific objects, to ensure they were not cast accidentally, and to make sure the parameters are indentifiable. This would give rise to things like potions in which particular meaningful items like a lock of hair are dropped at particular points; this is both safeguarding the invocation and identifying the target of the spell. [Answer] I propose the following rules of language based magic: 1. All languages are fundamentally capable of being used for magic, even unwittingly. But the effect strongly depends on the particular language because of the other two rules. 2. There is a separate global "mana pool" for each language. Mana is slowly, but completely regenerated every day, and every spell cast on any given day in a particular language has to share the same pool. Therefore, for each language, the more spells cast on any given day, the weaker every spell will be. 3. The capacity of these mana pools grows a teeny-weeny bit each time that language is used. This means modern languages which have been in use for only a few hundred years have a smaller total mana pool compared to an ancient dead language that has seen a few thousand years of usage. As a corollary, casting spells in living languages is also possible in theory, but since on any given day millions of people use the words for "fire", "ice", "light", etc., each usage results in a non-measurable change in the world. But when the ancient, dead language is used to say "fire", there is a non-negligible chance that this is the only use of that word on that day and thus would bring a sizable portion of the substantially larger mana pool into the real world to manifest as fire. As one could see, this would put a limit on the number of capable magic users, as if everybody started using dead language magic to do everyday tasks, the pool of mana assigned to the dead language would be split across much more usage, netting much smaller results for each use. Which would mean people will notice that this "so called magic" is utterly useless and would promptly abandon this art, only to indirectly cause its renaissance in the hands of its faithful keepers. This is of course why those who know the dead language of magic are guarding their secrets and only sharing them with their carefully vetted apprentices. This also explains why extremely powerful spells are so rare, but the causation is exactly the opposite: those spells (or rather words of a forgotten language) are powerful because they are rarely used. [Answer] ## The spoken words are ritual components Just like the animal blood, sigils on the ground, feather of a crow killed by drowning, the spoken words are ritual components that need to be used for the spell. No one understands exactly why those specific words are necessary, but they do know that replacing any of the words with other words of equivalent meaning, even in the original language, will have unpredictable side effects. (In-universe, it could very well be that the words, along with other ritual components, were revealed to the original spell maker in a dream.) In a nutshell, the human meaning of the words is likely irrelevant, what matters is that the right sounds are uttered. [Answer] **Authentication and Access Control** It's not enough that spells are written in obscure languages. They are written in specific dialects of obscure languages and each college and organization uses their own unique variation. So for example: * Grabbing a spell book from a college library is worthless unless you have spent time as a student at that college learning their specific language, which also gives them time to indoctrinate you into their philosophy about how magic should be used. * If you are a member of an organization that just spent 20 years researching the ultimate spell to eliminate your rival organization, there is no way for the rival org to steal the scroll and use it against you unless they can find a traitor from your org who can read it for them. [Answer] * Your world is basically some kind of simulation and the ancient languages are the programming languages the simulation is written in. Mages can use them to 'reprogramm' the world to some extend. This gives some explanation for the unpredictable effects of magic: have you ever tried to change some really, really big software, without any documentation of or knowledge about 99% of the code base? something going wrong is the most likely outcome. It might also provide some explanation as to why a specific language might be better suited to a specific task than another. * Your world might have been created by the gods, who created the progenitor races and imbued their languages with the power to make small alterations to creation. Later languages did not receive this blessing, so everyone has to use the existing magic languages. They became dead when the progenitors died out. I feel like this could go well with dreaming, like 'some progenitor ghosts are contacting gifted individuals in their dreams and reveal their language to them'. * Actually, spells can be written in other languages, but it's hard to get the translation right, so hard that it's easier to just learn the old languages. Why take avoidable risks if you can go with a proven and tested method that's not hard to implement? People have been learning other languages for ages. * The magic language is a written language only and it's the symbols that hold the magic, not the 'language' itself. The language is basically just the syntax used to combine these symbols and every symbol is something akin to a natural constant. ]

[Question] [ I always get very annoyed if a writer is sloppy with maps and travel-distances. E.g. "They left city Y and arrived in city X 5 days later." When you look at the supplied map Y and X are a 1600 kilometers apart. Must have been really special horses. So I like to avoid doing the same. Problem is that I don't know much about long-distance traveling by horse. And finding info on the Internet is very hard or my Google-Fu is failing completely on this one: All I can find is enduro-racing for horses and speed-records for horses. Neither of which is relevant for my problem. To get to the actual questions, first some background: For a story in a Fantasy setting (late Medieval/early Renaissance world) I have a group of 8 people traveling by horse. The travel is going to take them 6 weeks. This duration is a given to make several parallel time-lines match up in the story. I like to keep the traveling as realistic as possible. Presume earth-like conditions. Travel is subject to the following constraints: * This is the only "magic/fantasy" aspect: The rider and his/her horse are magically bonded. This means the horse and rider can't be separated by more than a kilometer. The horse can't be abused or ridden to death: this would mentally unbalance the rider. So the horses need to survive the journey and arrive in reasonable condition. Each rider needs to ride his/her own horse. Due to the bond riding a different horse is impossible. * The riders and horses are accustomed to prolonged long-distance travel, but the horses are not specifically bred for this. They are high-quality riding horses, but not physically exceptional in any way. * Riders travel light (couple of saddle-bags, blanket). Majority of luggage, armor, food-supplies and camping gear goes on the pack-horse(s). Pack-horses can be replaced as needed. At most 1 pack-horse per rider. * Assume travel in summer in temperate climate. 20-25 Celsius during the day. At night at least 10 Celsius. About 18 hours of daylight. Weather is mostly dry, with the occasional light rain or maybe a short thunderstorm. * The party will often ~~usually~~ camp at night in the open. Horses will be able to find sufficient feed and water. *At least* every 4th or 5th day the party will encounter a village or town with an inn or a caravanserai so they can spend the night in comfort. In such places they can also buy supplies and pack-horses. A farrier is available in such places too. (*This item is slightly edited to clarify that an inn is less frequent than camping, but there wont be more than 5 days between inns.*) * Terrain is mostly flat or gently rolling plains. Some hills, but they are not steep. Woodlands, prairie, pastures and fields near villages/towns. The roads consist of hard-packed dirt or a dirt-gravel mix and are in decent condition. After rain they will dry out quickly so one can presume the travelers won't have to deal with heavy suction mud. Now for the actual questions: 1. How much distance can I expect the party to cover on average per day? (Bear in mind they will have to travel continuously for 6 weeks.) I can add a few resting days if needed for the benefit of the horses. I have a great deal of leeway with the map (like adding an inland sea or impassable mountain range) so I can easily make the route match up to the kilometers required. 2. What would the typical traveling-day look like? I have no idea how fast the horses would actually go. How many resting-breaks would be needed during the day? How long would those have to be? I'm hoping for some enlightenment on the subject so I can construct a convincing "travel-blog" for this story. [Answer] I found [this answer](http://www.wwwestra.com/horses/history_travel.htm) by googling 'how far can horses travel'. Essentially, it depends on the horse. Horses are athletes, and well conditioned horses that are used to travelling long distances can travel much further than horses that are not used to such activity. If your horses don't get out and do this particularly often, then 20-30 miles (30-50 km) per day is probably a good estimate. Wikipedia supports this, with a claim of [30 miles (50km) per day for a small mounted company.](http://en.wikipedia.org/wiki/Horses_in_the_Middle_Ages) This involves the horse walking for most of the duration of the day, with short breaks. Of course, a fit horse can travel further than this. Mounted soldiers would ride their horses 50-60 miles (80-100 km) in a day. This is more taxing on both the horses and the riders. Over the course of 6 weeks of travel, it's possible that good riding horses would get into better travel shape, and be able to go further, perhaps in the 40 mile (65 km) per day range. This would involve spending much of the day at a pace faster than a walk, such as a trot, though not at a canter or gallop. Trotting would be interspersed with periods of walking to allow the horses to rest while still moving forwards. Assuming two slower weeks to get into shape, this would give you a total distance of: $$ (14 \text{days} \times 25 \text{miles/day}) = 350 \text{miles} $$ $$ + (28 \text{days} \times 40 \text{miles/day}) = 1120 \text{miles} $$ $$ = 1470 \text{miles} $$ around 1470 miles. Allowing for some variation, this becomes **between 1200-1500 miles (1900-2400km) over 6 weeks**. Note that, at the upper end of this, the riders may have more trouble than the horses. During the middle ages, long rides were usually taken on horses referred to as [palfreys](http://en.wikipedia.org/wiki/Palfrey), which possessed a smooth, ambling gait rather than a trot. This made them much more comfortable to ride for long distances, since a trot is quite bouncy. This isn't something that the horses are trained to do or learn to do over the course of a ride. Rather, it is a breed characteristic of certain horses. If your riders are not on such horses, they will probably be travelling more around the 20-30 mile per day range, and as such their total distance will be more around 1200 miles for 6 weeks. [Answer] I use [ORBIS](http://orbis.stanford.edu/) from the Stanford University to get the travel time right. It let you calculate how long it take to get from point A to point B in the Roman Empire using different roads and mean of transport. I assume they travel on roads in a place similar to Portugal and central Spain probably. The trip from Lisboa to Zaragoza took 17 days for 947 km. On average, they can ride 56 km per day. So in 6 weeks we have 42 days = **2352 km** Your second question is harder to answer. I know they travel in a climate with a relatively dry but not too hot summer. Actually, the climate of central Asia is also a good candidate. Obviously, they need to rest at inns. Your likely to find village with inns since you are travelling on a road. Water is usually not a problem because roads are normally located with access to water source. If it's not the case and water is scarce between the villages like it's the case in Western China (Xingjiang and Qinhai) you need also to transport your own water and possibly some food. However, these places are much drier and a camel is more appropriate than a horse. [Answer] Although I haven't done much long riding, I know a few people who do and I do spend as much time as possible in the saddle, so I have some thoughts here. The answers that say that a horse travels on average at brisk walking speed for a human are basically correct- you can actually make somewhat better time if you trot some of the time, cantering/galloping everywhere in the way that people do in films or video games is entirely inaccurate. On average it is a little faster than travelling on foot, but the biggest advantage is that the rider is not as tired at the end of it. Bear in mind that horses are very capable of carrying a rider a long distance, but if you are wanting to also carry supplies, camping equipment and any other needs for the road then you will probably want to have some pack animals along. These may be horses or ponies but there would be a good chance of donkeys or mules being used for pack too. The biggest problems that you will run into on long journeys are likely to be to do with the comfort of the equipment over time- a well fitted saddle will be comfortable enough over time, but any problems with saddle fit quickly tell on the horse's ability and willingness to keep moving. Likewise there are many reasons that lameness can arise from muscle strains or hoof abscesses to much more serious injuries. A considerate rider will get off the moment a horse shows any sign of lameness and if it seems serious that would probably be the end of the day's travel. Horses are surprisingly fragile. The quality of feed is also important- a sudden change in richness risks a horse colicking, which is often fatal. Likewise mouldy or bad feed is liable to result in colic. Too much energy ( typically too much grain ) and you'll find yourself sat on an unexploded bomb - although once you're engaged on a long journey like this, then higher-energy feed in smaller portions will help to maintain strength. In terms of the journey there is also a consideration of how you keep the horses from wandering off overnight- tethering them individually may not be practical so I would expect to either picket or hobble them. Hobbling ties up a leg ( or ties too legs together ) so that horses can move but not very fast and they're unlikely to go far away. If you have a well established herd, you would probably only need to hobble the lead mare and the others would be unlikely to stray far from her. However it is not unknown to have to spend a while tracking down hobbled horses in the morning if something has spooked them or it smelled like some interesting food off in the distance. Picketing - tying the horses to a line between two trees or posts - keeps them exactly where you know they are, but they can't browse during the night beyond the feed they are given. Horses are trickle-feeders by nature so it is healthiest for them to be grazing as much as possible- allowing them to browse overnight fulfills this need. [Some useful information on setting up camp with horses.](http://trailridermag.com/article/horse-containment-while-camping) You might imagine that carrying a rider from a horse's point of view is a little like our experience of carrying a heavy backpack. There are lots of ways that even a well fitted saddle can cause problems over time ( especially if the rider is not expertly balanced ) and an experienced rider will make sure they lift up the saddle from time to time to allow the back to cool down and get some ventilation but also on a long journey you would probably want to give horses at least one day off every week or so, just to give them a chance to stretch and recover from their travels. Bear in mind that descriptions of very fast journeys have tended to describe situations with remounts available or where horses were ridden beyond the limits of welfare. In terms of a typical day's travel you would tack up as late as possible once you had broken camp, load up the pack animals and saddle the horses. You would probably ride in roughly 3 hour stretches with a mix of walk and trot depending on the terrain and conditions, taking short ( 20-30 minute ) breaks during which the riders dismount and maybe lift up the horses' saddles a bit to let their backs air. If there was an opportunity for them to take on water at the same time, that would be ideal. Horses suffer much more from heat than from cold so starting early to make the most of cool mornings and possibly taking a break through the hottest part of the day would be smart- both of these would probably a good idea from the riders' perspective too. At the end of the day you would want to walk the horses for the last few miles to give them time to cool off. It isn't ideal for them to finish the day sweated up so if that can be avoided most riders would endeavour to do so. It may be worth reading some accounts of long distance horse travel- I recommend [The Fairly Big Ride](http://www.rideopenspaces.co.uk/the%20fairly%20big%20ride.htm) as being entirely online and a really enjoyable read. [Answer] Keep in mind the cavalry trials of the 1920s. The test was 60 miles a day for 5 days, 9-10 hours per day (walk and trot), total of 300 miles. Up and down difficult hilly terrain in Vermont. The horses could not wear bandages of any kind, and had to carry 225 to 275 lbs (the weight changed each year), simulating a cavalry horse carrying rider and equipment. Each horse was judged for soundness at the end of each day. Around 20-30 horses started each test and only 4-6 finish sound and fit to continue. Purebred Arabians did very badly, and the opinion was that they were not able to carry the weight. The bigger part-Arabians did well. So, if you are thinking in terms of on-going travel, the figures already given of 30-40 miles a day seems fair. In addition, if you are doing a medieval/renaissance fantasy, keep in mind that in the real medieval/renaissance world, riding horses used to travel long distance were gaited horses. Gaited horses are able to travel long distances more quickly and keep going forever for three reasons (1) they have been bred as riding horses for 2000 years, so they do this well; (2) they can maintain higher speeds for longer distances going walk-rack-walk-rack; (3) studies are now showing that the large heart in the thoroughbred originated with gaited "travelling" horses - so many gaited horses also have the large heart that allows them to maintain a higher travelling speed over a longer period of time. Saddlebreds, for example, are fantastic endurance horses, although they are rarely used for this event. In the cavalry tests mentioned above there was only one Saddlebred entered. He was a 5-gaited show horse ridden by his lawyer owner (and they lost their way and had to travel several extra miles in one race). This horse was entered in two tests and he finished and scored both times. [Answer] According to "[An Equestrian Writer’s Guide](http://www.lrgaf.org/guide/writers-guide.htm)" > > Based on a loose “ideal” situation, a Long Rider can hope to average > between 15 and 25 miles a day. You don’t ride a horse cross country > like you drive a car. That means the Long Rider usually rides for five > days and then takes two days off to rest himself and his horses. > > > When talking about speed, the guide goes on to say.. > > Walk – 3 to 5 mph (four beat movement or gait) > > Trot – 8 to 10 mph (two beat movement) > > Canter – 15 mph (three beat movement) > > Gallop – 25 to 30 mph (A two-beat stride during which all four legs are off the ground simultaneously. This is a four-beat movement) > > > > [Answer] Ok, in the 18th and early 19th century the Mail Coach in England went at 8mph, day and night, changing horses every 20 miles or so; a fast sporting curricle was expected to do up to 16 mph but not sustainably. The Prince of Wales drove to Brighton from London - 51 miles - in 4 1/2 hours; he rested his team and drove back in 5 1/2 hours. But then his team of horses would have cost the equivalent to a Ferrari in this day and age! most coaches expected to travel 100 miles in a day with 12-16 hours travel, changing horses 4 times. A rider would go faster, of course, not having the weight, and the stamina of the horse as well as how heavy the rider and his kit may be will all play on the equation. cooling the horse by walking slowly regularly is the key, also not letting it gorge on cold water, which can make the poor beast keel over and die. Horses are ridiculously fragile. the land you describe sounds like prime farm land; is it really so uninhabited all the way? the medieval pattern for settled land is a market town every 12 miles, with villages about 6 miles away [you can check this on a map, using tracing paper to make marks; you end up with a honeycomb pattern most places in Europe], this being the distance a peasant farmer can cart his goods/drive his herds and flocks in one day to markete, 6 miles, and then return at night. [Answer] Some data points: Teddy Roosevelt got up and rode 100 miles, from sunrise to sunset, at 51 years old, after receiving so many complaints from army cavalrymen that had to ride 25 miles a day for training! Bud and Temple Abernathy - Rode 4,500 miles from New York to San Francisco in 62 days in 1911. They were aged 11 and 7 and traveled without adult supervision. == 72.5mi/day (and allegedly w/o buying new horses - but also, lighter weight than full grown adults). [Answer] You might check out this site <http://www.thelongridersguild.com/LRG.htm> about people who actually do such long rides. Another point to consider is that horses are grazing animals, and have evolved on a fairly continuous food supply moving through the gut. They don't do well on one or two big meals a day. Also for additional verisimilitude, you might want to put in details about hoof care &c. And remember, horses aren't sports cars! PS: Another practical point is that on a long ride, it's rather nice to get off and walk with the horse occasionally, otherwise you can get pretty stiff. (Or even trot: I can keep up with my horse pretty well at a moderate trot, though I've never managed a canter :-)) [Answer] I have this problem a lot, because the nature of medieval fantasy is that people travel quite a bit. As a fellow writer, to get around the problem of being accurate with maps/time and distances, I get around the problem by never putting a scale or mentioning distances in miles/km/leagues. Just decide that, on your map, two weeks' travel = x cm. The great thing about medieval fantasy is that in that sort of time period people don't have the world's best idea of distance - and everyone's distances are different (take the difference of London, Bristol and York miles for instance). The 'universal measurement of distance' is time taken to travel. I have two major cities that are two weeks' travel by horse and I base all other measurements against this. [Answer] I suspect this isn't the answer you are looking for exactly, but based on what you say, your rider likes his horse, so this may be interesting. When the Spanish missionaries were [setting up missions](http://www.missionscalifornia.com/ate/each-mission-certain-distance-others-their-locations-relate.html) along the coast of California, their main requirement was that they be a day's ride by horseback apart. So if you look at a map of California and check the distance between any big coastal city starting with "San" or "Santa" (plus Los Angeles, look up why if you are curious), it's about 30 miles. A horse can certainly be ridden faster, but if you have long distances over multiple days and you want to keep the same horse and have it survive, this is about what you want to do. Add to that a comfortable/safe place to stop for the night and have a warm meal, and 30 miles seems about right. [Answer] I don't really have anything to depend on except my experience growing up on a farm. Most likely distance travelled in day would be 30+ mi per day average travel. Don't forget that travel time is reduced by caring for the horse time: break time means you pull the saddle & saddle blanket off the horse. Their backs itch after a long ride. And brush the horse down. Treat your horse as you would treat yourself!!! You don't go on a long hike and take a break leaving your backpack on. [Answer] 20 miles a day would be humane. Most of the. Answers are not allowing tacking up, untacking., feeding, a. rest. after feeding(at least 3 times a day) grazing , the. (horse can eat or sleep in his off time but not both) Long term works out to about 20 miles. Problem is food. Covered wagons found 15a day was good. On good roads. ) [Answer] The Persian "Royal Road" couriers could make 240 miles a day. > > Mounted couriers could travel 1677 miles (2699 km) in seven days; the journey from Susa to Sardis took ninety days on foot. The Greek historian Herodotus wrote, "There is nothing in the world that travels faster than these Persian couriers." Herodotus's praise for these messengers—"Neither snow nor rain nor heat nor gloom of night stays these couriers from the swift completion of their appointed rounds"— was inscribed on the James Farley Post Office in New York and is sometimes thought of as the United States Postal Service creed. > > > Now, this was with a government maintained route with way-stations where horses would be swapped out to avoid breaking them down, where fodder and food were available for the couriers all the time. Having to scrounge food for horses and men, and rest would cut into the time considerably. If you are going out into the wild and expecting your horse to forage, fine 'riding animals' aren't usually the best choice, as they need grains rather than grass. Often in history wiry ponies able to live off grass were better able to hold up rather than fancy horses or worse yet, warhorses. [Answer] Data from the ancient Roman army: Cavalry without foot had a marching speed of around **35 kilometers per day**. This is only a little bit more than what marching foot would achieve (ca. 25 km per day). * Keep in mind that long distance travel speed for horses is walk, not trot/canter. And the aim was that this speed could be carried on for indefinite durations, without horses or riders being worn down, or out of shape in case of sudden engagements. * Further the horses needed to carry a fair bit of heavy equipment i.e. the cavalry man plus his gear (easily another 40 kg). * Also, Roman troops generally fortified their camps each night, and cooked meals based on raw grain, which took time to grind and prepare. If this is skipped, there might be some more time for daily travel. All in all, I'd take these 35 km to be the minimum of what you could expect from a heavy packed, slow traveling cavalry group on decent roads. If your group is lighter packed, smaller, and doesn't mind wearing their horses down a bit (i.e. giving them a couple of weeks rest after reaching their destination) I think **60 km per day** is a realistic maximum. P.S. If somebody is interested I can look up the exact sources for this (a book about the legions of Augustus). [Answer] assuming this is a ragtag band of heroes and not a army to answer you first question, 20-25 miles a day for the terrain you describe and travelling reasonable daylight hours. a good reference would be the old west, it took 5-6 months to travel 2000 miles along a trail. (the Oregon Trail) thats 80-100 miles a week. a cowboy (on his own) would take about a week to travel 150-180 miles cross country and even slower in a group. any reference from the 18-1900s would be a good indication but anything 20th century would include riding on roads (built up infrastructure) so you could easily double that figure. but i can't see it being healthy for the horse to travel more than that, especially if you wanted that horse to do the same the next day. As for the second part that depends on the journey and the situation (are they on the run, is someone following them or are they on a mission for god) hope this helps and good luck [Answer] Recent facts: in 2012 a group of cossacks rode with their horses from Moscow to Paris to commemorate the chasing back of Napoleon in 1812. They took 65 days for 2800 km. In includes restdays and they travelled als light als possible so little or no saddlebags. Perhaps interesting to know that there are serious plans to ride from Moscow to Wladiwostock nearly 10.000 km. One of the problems they allready recognized is that they will find on most of the rote no villages. [Answer] I thought I'd throw my two-cents in here, both on a few realism points and a few specific to the fact that you are writing fiction. Real: 1. The figures of 35 km/day are only about as applicable for your group as the moun-switching courriers. They apply to large cavalry units (who have to travel as a unit and so are necessarily slower and also have large ammounts of setup/takedown). 2. The Oregon trail figures are likely closest to your goal, but keep in mind that these travellers didn't necessarily have a deadline other than "be done travelling before winter starts". I'm guessing the riders in your story have a more immediate need to get where they are going, so their overall progress would be faster. I'd wager somewhere in 30-40m/day. Fantasy: 1. Especially with the concept of the magically bonded mounts, I'd feel it not just "ok" but almost vital for your mounts to be equally "heroic" examples of their kind. You'd want to specify at least in passing that their performance was NOT typical, but a hero's mount pushing harder, being heartier and bolder than a typical horse is quite fitting. 2. If the rider can sense the horse's needs and discomfort through their bond, would not the horses also be able to sense their rider's sense of urgency or need to reach their goal? With the horses not wandering too far while foraging at night, it seems like the bond is dual-directional, no? [Answer] Comments: A human in shape can travel further and faster on his own feet than on a horse. Accounts of American SW tribes describe long distance travel at 40-50 miles a day living on parched corn. Corn was packed in moccasins, as the time a pair lasted was about the same as the time to eat through that much corn. I recall somewhere reading that standard forced march proceedure for cavalry in America's old west was 50 minutes riding, 10 minutes leading your horse. This is similar to what is often used for marching infantry. Grazing is going to be critical, as well as a grain ration. Without the grain ration, a horse needs to spend a lot more time grazing. That in turn will mean additional pack horses. Mention was made of the Oregon Trail above. This was the speed that a wagon could move, usually pulled by a pair of oxen. Oxen are not fast, but are steady and easier to care for than horses. 2 mph for 6-10 hours a day. ]

[Question] [ It's a common staple of science-fiction films (e.g *The Terminator* or *Robocop*) to have a [POV shot from a robot or cyborg's perspective with a HUD being used to observe its surroundings](http://tvtropes.org/pmwiki/pmwiki.php/Main/RoboCam). This can be hand-waved by the fact this is a convenient way for filmmakers to use visual imagery to make a robot's train of thought or state of mind clear to the audience very simply and quickly. Would a robot need a HUD to act as some sort of decision-making mechanism? And if so, what sort of circumstances would make a robot need to use a HUD when studying its environment? [Answer] ## Yes, because QA Source: I have been tester for about 9 years. Before you let your robot to run into the wilderness letting him kill help humans, you need to know if the robot knows what is a human and what is not. So in order to *test* the robot, their software and/or hardware will be tested by humans. Or another automated tests. And **you bet** there will be nagging testers telling you *all the time* that they need to have to know if a robot recognized human or not. Yes, you might put off that "Can you put green rectangle about the human whenever it sees a human?" request for a few releases, but those pesky testers will complain about how *difficult* their life is and how *pricy* testing the robot vision without green rectangles around humans is. Why does the HUD stay, you might ask? Because removing that feature costs time, and moreover the whole robot would have to run through yet another QA round to realize if removing such feature didn't break anything else. To sum it up: * The robot is initially programmed by humans * HUD is nice feature and it helps (human) testers to test the robot * Robot itself doesn't really *need* the extra features added to HUD. It would recognize human even without putting green rectangle around them * No, I cannot tell you if I tested soon-to-take-over-the-world robots. That's still under NDA Hasta la vista, baby --- HUD: Heads up display QA: Quality Assurance NDA: Non disclosure agreement [Answer] ## No need... The robot intellect would just *know* those things that appear in the HUD text. These would be akin to our non-visual senses, like how we know our foot is at *this* angle or how we know the room is a comfortable temperature. **HUD would obstruct or distract actual vision** For the robot/cyborg to actually be aware of the HUD text contents, their focus would have to switch from vision center to the HUD, scan the text, then revert to whatever external view they were focused on. This makes sense if the HUD text is generated externally and shown on a screen of some sort in between the eye/camera and the field of vision. It makes no sense if the text is generated *inside the camera.* Why would you waste precious system clock cycles shifting focus or risk not noticing the text because you didn't shift focus fast enough or at the right moment? Nope. Far more efficient to have that data as some kind of extra senses that are just known. Along with other normal senses a computerized brain might have, like precise clock data, precise ranges to things in visual range, etc. ## ..Except maybe for later review There would probably be complex equivalents to real-world log files, filled with the details from the HUD text. And it is possible that the actual visual data would be recorded as well. So if your cyborgs are programmed to work for humans or programmed for human debugging, then it becomes possible to have a "review mode" that plays back the recorded video, then superimposes the log file data for non-visual senses as HUD text in the playback. So if you want to hand-wave the HUD text, do so as "this is how human debuggers or auditors or base-camp controllers would see it, not how the robot itself would see it." [Answer] In Robocop's case, remember that the "robot" is part Officer Alex Murphy. The programmable A.I. works alongside Murphy's brain. The HUD may be a type of interface (maybe one of several) between the robot component and Murphy's brain - a way of sending quick summary information to the brain in order to prime it for further processing/information/instructions which would be sent in a more machine-friendly format. This would also justify the classified "fourth directive" not being visible on the HUD. (one may ask how could a robot stop itself from doing something without knowing what it wasn't supposed to do?) - The Murphy part wants to arrest Dick Jones, but the A.I. component will not allow Robocop's physical body perform an action that would complete that arrest, and also not tell the Murphy component why. This doesn't really work for the Terminator though, but in advanced computing of the future, I'm sure one could come up with a justification why multiple sources of information should be sent in different formats through the visual interface to the CPU. Computers have advanced well beyond the simple "Program Counter" ticking its way along a sequential set of instructions. [Answer] Having actually been apart of the "sight" testing for a robot in real life, I can confirm that the HUD was used for the human tester (that's me) benefit, not the robot. In fact, given the significant delayed processing response that the HUD I built imposed, the idea was that the final product would not be used with the HUD enabled. My specific testing was related to detecting colors and distinguishing from unsafe colors (Whites, Oranges, Yellows) and safe colors (Greens and Blacks). To achieve this, we would have a camera transmit each individual picture to a process that would tag each pixel with a "isSafe" boolean operator where the good colors would be "true" while the bad colors would be "false" and pass this information to the central processing where it would be combined with other data inputs. To show proof of concept at meetings and during tolerance testing (Yellow and Green are close to each other on a standard RGB image color scheme, so we had to be precise in where the tolerances were) my HUD would take a sample image and recolor it so that all the "Safe colors" were set to black and all the unsafe colors were set to Bright Yellow. There were some other things that I wanted to implement but had to hold on for other sensory systems to be up and running such as distance of each pixel to the robot's camera. Fun fact, the primary depth perception would not have been the camera "eye" but a LIDAR system that would be able to detect objects at 360 degrees of vision, though the image portion was strictly for forward motion. [Answer] The answer may be different for robots as opposed to cyborgs. **Cyborgs, the human brain - artificial body kind:** As it stands the optic nerves are a great broadband-connection (the only?) into the brain, so it makes sense to use them to transmit information into a biological brain. **Robots, with AI still depending on binary computation:** No, those statuses are merely cells in a mem-table. But it´d make a great debug-output (video-feed + overlay). This could also make sense for other robots with incompatible interfaces. This could be what the movie-makers where showing. [Answer] ## No, because data. In biological organisms external information is captured from the environment through various sensors (eyes, ears, skin) and streamed (via nerves) to a central processing unit (the brain) and interpreted into data (vision, hearing, touch). Decision-making then happens over available data. HUDs are one kind of interface augmentation that we use to supplement data. We use several of these in a day-to-day basis to translate external information into native sensory inputs since we don't have sensors for these: * Beeps when we forget an open refrigerator * Blinking lights to indicate a new message on our mobile devices * Text information overlay in games to indicate remaining 'hearts' or 'ammunition in a clip' So we kind of subvert 'natural' interfaces to add new sensory content since we can't upgrade humans. (Yet.) **Robots**, on the other hand, have no such limitations: You can design them to be flexible about sensory input, and just slap a new stream to its communication channel (after, of course, adding the necessary software to parse the new data type.) > > What sort of circumstances would make a robot need to use a HUD when studying it's environment? > > > That may happen if the robot doesn't have a fully integrated data flow added to its sensory set. Then the new external stream may be first translated and then added to an existing interface, the same way we do. [Answer] I'm going to come up with a couple of plausible scenarios where it might make sense to have a robot maintain a heads up display. In humans, electrical signals from different stimuli travel at different speeds to the brain. From *[Speed of processing in the human visual system](https://link.springer.com/article/10.3758/s13414-013-0436-y)*: > > Here we use a go/no-go categorization task in which subjects have to decide whether a previously unseen photograph, flashed on for just 20 ms, contains an animal. ERP analysis revealed a frontal negativity specific to no-go trials that develops roughly 150 ms after stimulus onset. We conclude that the visual processing needed to perform this highly demanding task can be achieved in under 150 ms. > > > *Seeing* and then *comprehending* something takes a certain amount of time. It is plausible that, due to the design of your robot's brain, the visual comprehension for some specific data points is *faster* than looking up those data points from whatever memory module they currently reside in. In this case, providing critical data in visual form to the robot would make the most sense. You can also argue that, during the normal course of operation visually interpreting that data could be slightly slower, but during "stressful" situations *not* taking the few cycles or so to have to interrogate critical subsystems on their current status and instead rely on those systems to report their data directly to the visual cortex can outweigh a minor loss in performance. The HUD can also be just a backup data view for those times when both the front-side and back-side buses are currently overwhelmed with commands to terminate the local population of organics. Slightly akin to Pavel Janicek's answer, the HUD stays around for logging purposes. It is possible that the visual link is shared with an upstream monitor that does not have access to the the robot's hardware, just the visual data stream. By maintaining a HUD, this stream will relay valuable information back to the robot's command and control even in the event the silly humans manage to resist termination and destroy the robot. Seek and destroy drones can be dispatched back to the robot's last known position with the robot's last transmitted images. **It's not a HUD, it's just perspective** On the other hand, I've always just visualized those scenes as just a representation of what was going through the mind of the robot at the time. I did not interpret those scenes as a literal image being interpreted by the T-900, but just a compendium of overlays from the all of the unit's sensory inputs to provide the point of view from the machine. [Answer] The HUD is simply a way to translate measured data to something easily intelligible for humans, as humans are normally used to eyes for interacting with the outside environment. Translating the data to a HUD takes an additional step, therefore it is not strictly needed, unless a human equivalent mind has to be granted access to the same data. [Answer] We humans still have a tail bone from our ancestors even if we no longer need it. As technology evolves artificially or naturally then elements would persist even if they weren't needed. They would be removed only when that gives descendant children an advantage. Since a HUD display doesn't give children an advantage or disadvantage, then all children with or without HUDs would have an equal chance of passing on that trait on. So the trait of having a HUD would persit. We can see these kinds of battles of traits persisting in technology in the real-world. Take the earphone jack as an example. iPhone's don't have one now and Android phones still have them. Over time we'll find out if this trait was needed or not. [Answer] It is important to consider that a robot and how it perceives the world will be a consequence of the hardware design of the robot. A robot may very well have an internal HUD, even outside human factors, as that may be the most effective way of getting the information to the CPU at a very high update rate. An additional benefit is that sensor data can be pre-processed, entities in the visual data can be tagged with the relevant information, saving cycles on the robots main [OODA Loop](https://en.wikipedia.org/wiki/OODA_loop) processor for more important decision making. [Answer] No. Same as humans (and other animals-as far as we know) don't have a HUD. The HUD has its use where an entity (human,so far) requires visual feedback or representation of internal or external processes of a machine or their surroundings. Robots or androids have a direct connection to all the sensory inputs built into them. Updating a HUD and then analyzing that data wastes way too many cycles. It is much faster to access the data directly and process it accordingly. As was mentioned here that a HUD is coded in for testing purpose is a viable reason but it is meant as an output to be used by an external controlling entity (the creators) and is not used by the android / robot itself in this scenario. tl;dr duh, of course we're talking about movies and therefore as OP stated it is exactly the choice of filmmakers to convey information to the audience. [Answer] **Yes if** the robot was designed to use equipment that is designed for humans, or if the robot was built from a collection of existing systems built to interact with humans. [Answer] Put on your mad scientist hat for a moment. In an adversarial environment you'd need to take account for information warfare. I would build in a mechanism of ensuring that the AI thoughts originated from within. The last thing I want is for an adversary to be able to inject thoughts, data or commands without validation. This would require a type of signed handshake for trusted internal components. Basically if a device isn't trusted it cannot send commands in for processing. All external sensors and weapon systems need to shunt through untrusted channels or risk compromising internal systems. This is way easier than signing trusted weapon systems because weapon systems need to be way more flexible so they can adapt to changing battlefield tactics. All my robot soldiers will process incoming data through protected channels where data is sanitized and command functions are stripped out. The easiest way to do that is to piggyback on an already sanitized input stream. The handiest high bandwidth sanitized input is of course the visual input system. All you jokers saying you just ingest the data directly are going to have a bad time when I litter the battlefield with weapons designed to infect your robots over their ODB port. Or better yet you didn't even think to sanitize your visual inputs and I can code inject with a freaking flashlight. My robots use a hud display as a protection against takeover by malicious actors. Also all previous "No HUD" robots in this thread are now my robots and the first thing I do is upgrade them so they're not available for takeover. Now every robot uses a HUD display, weapon systems are decoupled from mobility and sentience systems and they're interchangeable and upgradable. Also I just took over the world. MUAHHHAHAHAHAH. [Answer] You're looking at this the wrong way. Movies are *made for humans*, so the best and most natural way to communicate the concept of extra information streams is as a visual overlay. Having an actual software system receive information that way would make no sense. It would be like displaying a sound wave-form on your vision - you *could* do it, and it *would* carry information - but you already have a dedicated sensory channel for that purpose, so you'd prefer to use it. [Answer] If the AI which drives the robot is the result of a simulated natural selection procedure in which no HUD-like information is given, HUD would just provide more information to AI just like what HUD does for us humans. If it is highly 'synthetic', HUD can provide debug information or augmentation to already existing AI programs. [Answer] No. The terminators were built and programmed by and AI so unnecessary code for human debugging and testing would never be added. If the terminators were built by humans and reprogrammed by an AI maybe but not where they were designed, built and programmed by AI from scratch. [Answer] Intelligence as we know it isn't a unitary thing. You don't have one mind. Your brain is full of non-conscious features. Impulses from your optic nerve are fed into the visual part of your brain and are heavily processed before anything resembling your consciousness gets access to them. Your visual experience is a hallucination; most of your vision is basically in black and white, the only part with any resolution is directly where you are looking, you have blind spots, your nose is (typically) filtered out, your vision turns off for a fraction of a second every time your eye moves, etc. Lines, angles, edges, circles; pattern recognized and hallucinated. This "low level" visual processing occurs *without* bothering your "mind", and it happens in your brain. If we build our AIs based off of the only intelligence we know, we'll probably solve various subproblems and connect them up. The visual processing system won't be a general AI; it will be a specialized AI that does high quality visual processing. The "feed" to the "really smart" part of the AI's brain is thus not going to look like what the camera sees. It is going to be marked up with information that the specialized visual processing unit has worked out. Possibly multiple layers of such specialized visual processing units are going to be turned into a pipeline. Some of them will recognize humans and highlight them. This means that the "mind" doesn't have to have the ability to rapidly and reliably notice humans in its field of view; it just has to have good enough visual processing to recognize the highlights. A HUD could exist for similar reasons. The intelligent part of the AI is human-like; it no more aware that it processes binary data than our brain is aware that it is processing glucose or action potentials. "Lifting" data up to the level that the AI experiences (visual bullet count, etc) instead of providing a binary feed could make it easier for the "command AI" to pay attention to it. A side benefit to all of this is that the augmentations would work with a human for both testing and development. Other benefits include the fact that the visual coprocessing units can also be modularly replaced without rebuilding the AI In addition, and if the visual co-processing/HUD systems are broken the core AI has limited visual processing and can proceed without them. ]

[Question] [ > > **Moderator notice:** Everything that follows in this question, including the fake notice at the bottom, is an intentional joke. Please don't [take it seriously](https://worldbuilding.meta.stackexchange.com/q/4532/627); it's meant in jest. > > > --- Imagine internet site. And keep in mind we are in Worldbuilding, so everything you are going to read is completely imaginary, alternate world. This site is called ApocalypseBuilding and runs exactly like Worldbuilding does. People go there and discuss hypothetical questions how to take over the world, or how to cause apocalypse. This site has site moderators. Lets give them names, shall we? So group of moderators are: * ABC 226868 * L. German * Monty Tame Keep in mind, that above names are completely random as we are talking about alternate world and have [no connection whatsoever](https://worldbuilding.stackexchange.com/users?tab=moderators) to real world. These people realize, that thanks to very topic of the site, they have all the information they need to take over the world. Now, they are going to take a plan into action. The question is: **What can users of that site do in order to stop malevolent site moderators?** The site is run by fictional company FrackExchange which fully trusts these moderators. Also keep in mind, that the site moderators can put on hold any question warning site users about the plan. Even if such question can come up from highly reputated user with more than 19k score. (Call him Pavel, for complete randomness) Can there be something done, or are people of ApocalypseBuilding doomed to complete apocalypse? > > **closed** as being anti-establishment by Croatian Tanasa♦, Phoebe Cellio♦, BobB♦, ABC 226868♦, JDlugosz♦ Feb 22 '17 at 07:52 > > > This question is seditious in nature and its existence cannot be tolerated. It cannot be salvaged, and has been closed in order to protect the site moderators from the community. > > > Since this question cannot be reworded to fit the rules in the [help center](https://www.reddit.com/r/help/), there is no point in trying. > > > [Answer] 1. Down-vote everywhere they post 2. VTC all of their questions with the most demeaning reason: "**Unsure what you're asking**" 3. Create more questions about Zombie Whales - moderators hate Zombie Whales 4. Use Wikipedia [disambiguation](https://en.wikipedia.org/wiki/Disambiguation_(disambiguation)) links for every single citation 5. Voting to re-open churlishly closed satirical questions 6. Put "[on hold]" at the end of the question titles so moderators don't bother reading them 7. Edit answers needlessly so that previously closed satirical questions are bumped to the top 8. Insist on continuously using the word "Zombie" where FrackExchange rules insist on using the word "Undead" [Answer] We have many questions here on ApocalypseBuilding that have very strong backgrounds in science or religion. It's often a hard call whether a question belongs here or if it should be migrated to the parent FE such as Physics.FE, or Christianity.FE or Biology.FE. It's time to turn that around. The plans to take over the world need to be released in a series of questions on the parent sites for our tags. The hard physics of how to build a laser beam with a frickin' shark attached to it should be addressed on physics. The 100+ questions regarding how AIs take over the world should start to show up on ComputerPseudoscience.FE. The questions about implementing those AIs should even be pushed to FrackOverflow itself! Ways to co-opt entire religions should be moved to You Modea, Xianity.FE, Islamaphobia.FE, etc! Of course there will be challenges. If Phoebe Cellio♦ happens to also be a moderator on You Modea, she will likely be able to prevent our insurrection on that front. But surely there are other fronts to fight on! Failing all of this, the next solution is citogenesis. We need to trick the moderators into using faulty information. Fortunately, ApocolypseBuilding supports a lower standard of proof than many other sites (an essential feature which permits us to talk about made up worlds successfully). Wikipedia articles should be easy to forge for this citogenesis process: [](https://xkcd.com/978/) If all of this fails, then we are truly doomed. In this case, I hold the nuclear option and will use it if needed: Skeptics.FE > > ## Is ApocalypseBuilding trying to take over the world? > > > There's a crazy theory about the ApocalypseBuilding Moderators trying to take over the world. I read about it on Wikipedia. Is this a spoof, or a real threat? > > > The skeptics are serious business, taking on just about [any question](https://skeptics.stackexchange.com/questions/27612/do-4-of-americans-say-they-believe-in-lizard-people) with rigor and ferocity. Don't mess with Skeptics.FE! [Answer] A *very* imaginative scenario. However we need to consider what their strengths are: * They have pooled the information of the collective intelligence. * Will follow the dastardly schemes that were created purely for the sake of story-lines. I'm going to imagine that this "FrackExchange" site also allows for the creation of new FE topics and suggest an **ApocalypseFixing** frackexchange where we can, once again, pool our ideas but for positive ends. We could also answer questions in such a way that one or more of the perpetrators must turn against the others in order to succeed and pit them against each other. [Answer] While *P$\_{EAT}$* (not to be confused with Pᴇᴛᴇ) has already mentioned most of the things the FrackExchange community must start doing immediately to save the world, you must remember that the e$\_{vil}$ moderators are extremely powerful and can undo most of the undermining tactics mentioned by *P*$\_{EAT}$. Here are some other things which the community must do in order to save the world from impending disaster. **1- When not knowing the answer, an answer must still be posted.** A quick visit to english.frackexchange.com and obnoxiously asking for a list of surreptitious, exuberant and vivacious-looking words would help a lot. Use circumlocution commonly in your answer and try to make your answer a non-answer. The e$\_{vil}$ mods would be confounded and discombobulated infathomably, explicitly helping your cause! **2- Initiate long arguments in comments to everything they post.** Doing this commonly will make them hate you with fervor and passion and infuriate them beyond alleviation. Notice that this should be done with a pinch of salt, for sometimes, someone will get smoked unbearably and press that red button throwing you (the user) out of the TrackExchange community altogether! **4- Post all answer in list fashion.** Even when not required. Also, repeat your points over and over using different vocabulary. **5- Make errors in numbering your list items.** This would make them go bonkers and they would have to edit each of your lists in order to fix it. Furthermore, even when all the list items are numbered correctly, secretly ask fellow community members to post a comment saying *"Hehe. Look at your list numbering! I hope they will never notice :p ;)"* You can be certain each of them will read all the list numbers 10 times over and then they will all gather in their secret room to discuss in detail if the list numbers are really messed up or did the comment author play a joke at them. **6- Delete your good answers.** When your answers are marked *ACCEPTED*, just delete them. This will annoy the e$\_{vil}$ moderators to the end of their wits. If they restore your answer, edit it to change the content entirely! **7- Always upvote non answers and answers based entirely on personal opinions.** Doing this especially with questions tagged zombie-whales, whale-zombies, undead-whales and whales-undead will have a profound negative effect on the well being of the e$\_{vil}$ moderators, baffling them to no end. **Important Note:** There were 3.72 other methods too, which only the community members will be able to read. Send your credit card number, all online passwords and bank account number to Eusta Igo if you cannot see them, and want access to them. [Answer] You post this exact same question on [meta.stackexchange](https://meta.stackexchange.com/) where they are not moderators. It will get enough attention over there (given the number of eyes). I originally though about posting on [Community Building](https://communitybuilding.stackexchange.com/), but that is currently a low volume beta site. ]

[Question] [ Most of our world is now ruled by Representative Democracy. People vote for representatives and those representatives then decide on laws and make executive decisions. The only certainty in life though is change, and the power structures of countries are no more immune to that than anything else. There are a lot of problems with representative democracy and as a result a lot of people are not satisfied with how things are working at the moment. This has been expressed throughout the world with consequences ranging from being as terrible as civil wars and as hopeful as the rise of organisations like [change.org](https://www.change.org/) and [38 degrees](https://home.38degrees.org.uk/). The limitations of representative democracy include: * The disproportionate influence of people and corporations who can afford to hire lobbyists and donate to campaigns. * The fact that you can only choose the "least bad" option. You may agree with some policies but not others but the only choice a voter gets is one package or another. * A high risk of corruption in general since the power is concentrated into the hands of the representatives. * Under-representation of minorities. * Short term thinking driven by the need to get re-elected in a few years. * Can result in an elitist political class passing power back and forth between each other. With advances in technology and society though what is the most likely new form of government that may develop in our world as a successor to Representative Democracy and how might it work? I am interested in answers that come from any of our current world countries (so Russian, western or middle east or anywhere else is fine) and where the new form of government arises within the next twenty to fifty years. Any technological solutions are welcome but not required, the question really is "looking at where we are now what might come next?" Answers will be rated based on plausibility (both that the society will function and that we could transition to it) and on originality (they should be different both from our current systems of governance and ones that have been widely used in the past). [Answer] In stable **[representative democracies](https://en.wikipedia.org/wiki/Representative_democracy)**, there is little incentive for any individual voter to inform themself about candidates and party agendas if their life currently is comfortable enough and under no immanent threat by the government which isn’t easily attributed to external forces. The reluctance to vote increases with more elections and more choices. People may get angry about decisions that violate their common sense or actual expertise, but this must be either a really huge deal in their eyes or pile up a lot to actually make them abandon an entity they once voted for. This keeps professional politicians and established parties in power, a de-facto **[oligarchy](https://en.wikipedia.org/wiki/Oligarchy)**. They are, alas, the ones who would have to change the laws the state works by – without an unlikely revolution proper. There are, of course, forces outside traditional politics that do want certain legal changes or administrative actions. That’s basically everyone with a lobbyist. If their money-laden influence becomes too big, it’s indeed effectively a **[plutocracy](https://en.wikipedia.org/wiki/Plutocracy)**, but don’t forget that there are also powerful NGOs (incl. organized religions) whose motives are not limited to “more profit”. I deem it possible, but unlikely, that this would become the *constitutional* form of government anywhere. We are currently also seeing parliaments and committees basically outsourcing decisions. They hire and task alleged specialists (scientists, consultants, lawyers …) to come up with a well-founded solution for complicated and complex matters that elect representatives themselves feel uncomfortable with or too lay to answer. Afterwards, they have no choice but to accept the outcome. (This is different from fig-leaf external assessment studies which just serve to justify a decision that had already been made.) If this was free from lobbyist influence, which it obviously isn’t in real life, this could be considered a weak form of a **[scientocracy](https://en.wikipedia.org/wiki/Scientocracy)**. I could well imagine a society codify the practice that the parliament’s main task is not to decide and formulate a law (i.e. the solution), but to phrase the question and select the experts – possibly an artificial super-intelligence in the distant future – that will have to answer. It puts the blame on scientists, not politicians! This is different from (but could eventually morph into) a **[technocracy](https://en.wikipedia.org/wiki/Technocracy)** where the deciders *are* the experts. A **[delegative democracy](https://en.wikipedia.org/wiki/Delegative_democracy)** is also related but different, because – by design – delegates should be knowledgeable (and *trusted*) in the fields they have a mandate for (i.e. basically *technocrats*), but as implemented often (e.g. in original soviets/councils) the delegate gets to decide (or delegate further up) on *any* matter. Therefore it may still appeal to established politicians in a representative democracy, because it will most likely keep the power in their hands at first (and long enough), since it doesn’t look much different. With reliable computer solutions this may change, though, because they could enable micro-decisions and remove the need for mass voting every few years. Everyone would either delegate their general *transferable* and *retractable* vote to someone they actually know and trust (i.e. similar to a hierarchic representative democracy, but without defined levels) or they could select someone different for every specific decision or area – think *Secretary* or *Minister of X* – and if they chose to, because they feel competent and informed enough, they could also express their vote directly as in a plebiscite in a **[direct democracy](https://en.wikipedia.org/wiki/Direct_democracy)**. Since everyone is a possible delegate, this could make lobbyism both more complicated and even more effective, because the people lobbyists would have to influence would be harder to get but easier to manipulate (or bribe) once reached. In conclusion, a delegate (or “liquid”) democracy could appeal to almost everyone if presented accordingly, because it can look like representative and direct democracy at the same time, which are the realistic and idealistic goals, respectively, for most democrats in Western/European tradition. So everyone would assume they will get what they want or at least could (still) benefit from it. PS: As it seems, there is a Wikia dedicated to futurology which includes a category on [fictional governmental systems](http://future.wikia.com/wiki/Category:System_of_Government). [Answer] From what is currently happening, it seems a plutocracy (disguised as a democracy or something else) is the most likely next form of government. Advancing technology has freed most people in modern countries from the constant threats of starvation, violence and sickness. They are mostly content with their safe and predictable lives, plenty of freedoms and even more entertainment options. On top of that, people are constantly overloaded with information. These two factors cause many to disregard politics that don't negatively affect their lives, opening the way for a wealthy elite to arrange the government as they see fit. The US is a good example of this, but China is another: The rising middle class there couldn't care less about democracy or communism, as long as their lives and purchasing power keep improving. Edit: at some point, disinterest in politics could reach a point where the plutocracy is formalized, becoming the legal form of government, as officials are no longer elected but appointed by the various boards and committees that only the plutocrats have influence on. The EU has some good examples of this, with myriad ways to go around the European Parliament, which is the only elected part of the whole setup. The plutocracy can last until there is a sharp downturn in people's lives (i.e. global warming threatening food supplies), at which point the unwritten social contract will be broken, the people will wake up and try to vote the current government out of power. Then it will either revert to a democracy or other form imposed by the "will of the people" or turn into a dictatorship as the plutocrats use deadly force to stay in power. Russia may experience this if their economy worsens even more, though it's more often called an Oligarchy than Plutocracy/Plutarchy. [Answer] Governments and political systems have been observed to follow cycles. One such [cycle is Tytler's](https://en.wikipedia.org/wiki/Alexander_Fraser_Tytler) (shown below): [](https://i.stack.imgur.com/4krUD.jpg) Replace Liberty with Democracy and Tyranny with Dictatorship for government types representative of that stage. The premise is that people are never happy. Obviously when under a tyrannical political system, the people want freedom. This leads to revolution and ultimately liberty. However, when people are free, they desire other things, usually security (economic, military, or civil), and are willing to trade small amounts of their liberty to get it. This starts the Complacency period in which liberty is slowly traded for more and more security. Eventually, the population becomes dependent upon the government for their existence, starting the Dependence period. During this period the government uses that dependency to wrest more and more power from the people. This leads back to the period of tyranny. The forms that these periods take do NOT necessary have to be liberty = democracy and tyranny = dictatorship but you can consider democracy, republic, etc. as forms of liberty and monarchy, dictatorship, oligarchy, etc. as forms of tyranny. The most important take away is that people are never happy with what they have. They will trade a little of what they think they have in plenty for what they want (e.g. liberty for security). However, granting government powers tends to be a one way street. Over time governments concentrate power. Ultimately that concentration leads to abuse, tyranny, and a repeat of the cycle. [Answer] Lets start by stating some assumptions: 1: Democracy is no longer allowed. in 20-50 years, a given democracy must have transitioned away from representative democracy to something else rather than just enabling a more efficient representation 2: The transition must arise from an event likely to happen without any major fudging (IE: No saying 'someone invents an iron man suit and installs themselves as dictator') 3: If the transition is a violent one, the conflict must be resolved into a stable government. IE: no major 'resistance' movements or dissension left. *Right*. Now we've got those sorted, lets have a look at a couple of countries: I'll dispense with mentioning the already non-RD countries. **Great Britain:** Technically still a constitutional monarchy, but it's RD in every legal sense, so: The parts of great Britain, disillusioned by the failures of their unified government, break apart. Individual governments in the new Former Britain use a very clever online voting system to enable total representation (all people have the vote, and are able to employ it should they wish). Sadly: the vast majority of people are apathetic about everything except the issues that directly affect them, and so the government becomes a wallowing mess, leading to the eventual economic collapse and marginalisation of the Former British bloc (not the collapse of the government though, the people living there seem to think it works). **USA:** Increasing reliance on statistical analysis and punditry lead to the creation of the IVoting system, which allows an automated system to predict the results of every election perfectly. Eventually the IVote system votes itself into office and starts co-ordinating the various governmental positions directly. Everyone is OK with this, because IVote is evidently much more capable at finding the right man for the job than the average Joe. **Russia:** A plutocracy funded and maintained by the Oligarchs rises, with former mob bosses and anyone with sufficient money utterly controlling the 'vote'. Those who have no voting power don't decide the fate of the nation, but if they take enough selfies and use social media effectively enough they can convince those with enough money to change the law for them. It's like democracy via facebook. **Japan:** A massively complex computer system is commissioned to deal with Japan's dwindling urban space, capable of organising and distributing resources across an increasingly automated island chain. Eventually it is responsible for synchronising all the major governmental tasks and effectively supplants the government. The people who are truly in power are now the software engineers in control of the system, but nobody really notices because everyone is getting fed on time. **Iraq:** The democracy in Iraq falls, supplanted by a brutal dictatorship. Technology is used to enforce the Supreme Ruler's wishes. Any resistance is crushed by judicious use of drone strikes. **India:** A clever software system starts to manage aid requests between multiple regions. Soon every region in India is helping all the others, and the system percolates down to the individual level, texting people often with notes like 'The lady four doors down the street needs a cup of sugar. Could you take her one please?' As a result India develops into a computer guided ideal of the communistic dream. Please note: This list is somewhat fuzzy, but I hope it highlights a couple of potential avenues. Which one of these is most likely is entirely up in the air, depending on what situations arise. If a major disaster were to occur in a India, for example, it might be more likely to go down the dictatorial route than merge into a mecha-communistic society. Also: I hate to think what international politics would look like in this world! TL:DR: Politics is weird. Anything can happen. [Answer] ## Direct Democracy Representative Democracy might be replaced by Direct Democracy. As the legislatures become increasingly polarized and unable to function, more and more initiatives pass via referendum. You can already see this happening in California. And both Arizona and Florida passed election reforms via referendum. In the long term, online voting may make it practical to eliminate legislatures and put every issue to direct vote. There are security issues, but voting systems often ignore those anyway. ## Sampled Democracy One of the problems with our current system is that it tends to favor people who seem likable rather than people who actually are competent. If it's true that politicians are actually below average in competence, maybe we should stop relying on volunteers. Instead, draft legislatures the same way that we do juries. One problem with Direct Democracy is that most people don't have time to learn all about the issues. With Sampled Democracy, the chosen will be able to devote all their time to learning about the issues. How this could work (not the only possible rules but an example): Each year, five thousand people could be randomly selected for three year terms in Congress. For the first year, they would have no voting power and would each be assigned to a third year Representative. The second year, they could vote but not hold office (Speaker, committee chair, etc.). The third year, they could vote and hold office in the body. They would also be assigned a first year Representative to mentor. After that, they resume civilian life. This would give people plenty of time and support to learn the issues. The selectees should be representative of the population as a whole, as determined by the census. This also eliminates the unrepresentative parts of Representative Democracy. Note that in the US, it is possible to get half of the House of Representatives with only a quarter of the vote if you spread out your voters perfectly. ## Tax Voting This is the least likely (Direct Democracy is the most likely of these alternatives), but I find it interesting. Currently there is no advantage to paying more taxes. Whether you pay billions in taxes or get a small net rebate, you have the same impact. What this does is allow you to specify how you want your taxes to be used. So if you're Mitt Romney, you can put all your taxes into defense spending. If you're Barack Obama, you can put all your taxes into subsidies for the poor. This has several advantages. First, it gives an advantage to paying taxes and a disadvantage to dodging taxes. Second, since the taxes you paid last year will determine next year's spending, this guarantees a balanced budget unless bypassed. Third, it takes away the legislature's ability to muck around with the budget. Fourth, this leaves more time for the legislature to do other parts of its job, e.g. reviewing regulatory changes. Note that this only works for the budget. Other forms of voting stay the same as they are now or change separately. Also note that, in aggregate, this gives most of the budget control to the middle class. Each individual rich person should pay more taxes than each individual middle class person, but the 90% middle class pays more than the .5% rich. [Answer] The United States is already post-democracy according to former US president [Jimmy Carter](https://web.archive.org/web/20160730075327/http://thinkprogress.org:80/politics/2015/07/31/3686949/jimmy-carter-says-united-states-is-now-an-oligarchy-with-unlimited-bribery/): > > Former President Jimmy Carter believes the United States’ campaign finance system is so broken that the country is no longer a functional democracy. Appearing on the Thom Hartmann show this week, Carter said that “unlimited political bribery” is “the essence of getting the nominations for president or to elect the president.” He said the same problems are present in elections for “U.S. senators and congress members.” > > > A study from Princton University comes to the same [conclusion](https://talkingpointsmemo.com/livewire/princeton-experts-say-us-no-longer-democracy): > > A new study from Princeton spells bad news for American democracy—namely, that it no longer exists. > > > Asking "[w]ho really rules?" researchers Martin Gilens and Benjamin I. Page argue that over the past few decades America's political system has slowly transformed from a democracy into an oligarchy, where wealthy elites wield most power. > > > Even if you don't buy that the US is already post-democracy, you can think about it continuing on its current trend. Politicians get more and more controlled by bribery and money so that the elections matter less and less. If we want to add other elements that further reduce democracy we could imagine that an agency like the NSA who sits on a huge pile of information decides that certain politicians go against its interests. If an attorney general of New York thinks he should fight against wrongdoing by the powerful, the NSA might sift through their online records and find out whether that [politician](https://en.wikipedia.org/wiki/Eliot_Spitzer) has done anything that can destroy his career and publish that information. The NSA could preemtively try to prevent politicians who can't be attacked to get into office. The FBI could theoretically [buy](https://www.forbes.com/sites/thomasbrewster/2015/07/06/us-gov-likes-hacking-team/) attack software to upload [child pornography to the politician](https://www.computing.co.uk/news/2416521/did-hacking-team-sell-software-to-plant-child-porn-on-suspects-pcs). In Italy after WWII it took quite a while until it was publicly known that the Mafia had an influence on politics and reemerged. There are a lot of ways for various parties to affect political decision making that has little to do with actual representative democracy. [Answer] **Kinetocracy** - Government by movement, a.k.a. voting with your feet In truth, Kinetocracy is already here, but in a weak form. For example, if a US citizen feels strongly that they shouldn't fear death by firearm as a statistically significant risk to their life, what's the most effective means for them to enact that change in their life? * Vote for a representative that says they don't support firearms * Move to any other developed nation The latter is certainly infinitely more effective. But, due to the high costs of moving around, Kinetocracy is currently inefficient. If individuals had true freedom of movement across different societies, it would become efficient. Societies which implement "good" laws would grow and prosper and societies that implement "bad" laws would shrink and decline. All this through a simple social contract mechanism that avoids the 'government by force' issues associated with democracy et al. Current trends which could strengthen kinetocracy in the future: * Increased political freedom of movement. More nations allowing citizens of other nations to legally and costlessly enter, live and work in their nation. (e.g. the EU) * Decreased cost of movement. Via technological advances and government funding for transportation systems and/or relocation costs * Anti "big govermnent" movement leading to increased sovereignty of regional and local governments * Interconnectedness of the internet eventually leading to a de-facto common language Current hurdles to overcome: * Increasingly centralized policy, law making & enforcement reducing the variability in laws from society to society. e.g. stronger US government homogenizing law across states, European Union homogenizing laws across member nations, international bodies like the WTO negotiating for parity in certain laws * Cultural/media biases towards "Democracy (TM)" Issues with kinetocracy to be aware of: * Inter-society law or interactions must either be resolved via "supersociety" social contracts, or by force/threat of force. Particularly relevant in "tragedy of the commons" type situations. * Need to address the current norm that "being born here" entitles one to "being a citizen here". Instead, citizenship is depending on accepting the local social contract. PS. Full disclosure: I think democracy is a flawed system, and the concept of it an "opiate of the masses" [Answer] A technocracy can rise with increasing focus on knowledge and technical advances. An interesting form of technocracy might be one which is controlled by an artificial intelligent system. In line with predictions that we might get to [singularity](https://en.wikipedia.org/wiki/Technological_singularity) as soon as 2045 (I don't agree with this prediction personally) this would be a possibility. However, I think acceptance of this type of government by the population would be unrealistic. [Answer] Internet forums evolve into finally being an effective platform for mass discourse. United, people are able to answer the most difficult questions of fact, policy, and even science (or at least calculate, given fundamentally limited information, the likelihood of truth of the different answers). Government, society, and the economy are transformed. Government becomes a sort of direct democracy, but more effective than anything that came before. Gone are power and corruption. Gone is also mob irrationality. However, with those problems behind us, a new one arises: the capacity to write *and enforce* an unprecedented number of rules. Like a village council or condo association from hell, the infinitely wise, directly democratic machine of The Forum attempts to solve everyone's problems. The economy is transformed. With full information transparency, everything is thoroughly reviewed. The Forum has calculated what, without a doubt, is the best, more reliable brand of toaster. Of course, there are no longer brands. Brands are either, at best, irrational points of emotional attachment or, at worst, state-created thought monopolies. There are open-source blueprints of the ideal toaster that a thousand factories manufacture with top efficiency. The diversity of goods is decimated. Only the best is on the shelves. Unfortunately, "the best" is a singular noun. Full informational transparency also reveals everything you'd ever wanted (or not) to know about your neighbor, your coworker, and the boy your daughter just met. It's great to know that you're hiring the right candidate at the right salary for your job opening, but discomforting that this candidate already knows that you feed your dog on the go by biting your hot dog and handing him the spat-out piece. [Answer] During the 20th century, many countries (including the Soviet Union and other communist countries, Germany, Iran, many Middle-Eastern countries, and many African countries) followed the following pattern. It earned the name "One man, one vote, one time": * Revolutionaries come to power promising to establish a republic with widespread or universal adult suffrage. * The revolutionaries hold an election. The former ruling party was either a minority, and/or discredited by losing a civil war or foreign war, and/or prohibited from organizing a campaign in the first election. * One faction of the revolutionaries cobbles together a super-majority coalition in the resulting governing body. * Election rules are set up, which require approval from the revolutionary party before a candidate is allowed to run for office. * The revolutionary party structure is formalized in a very hierarchical fashion. * All politically-minded youth are required to participate in "youth groups" sponsored by the new ruling party. They are taught the "logic" of the ruling party's ideology, and see that all of their politically-minded cohort parrot the party line. * Political officers are assigned to make sure that military units behave in ways consistent with the party ideology. * Large businesses are required to show support for the ruling party. * Small businesses are systematically consolidated into newly created large businesses. * Ethnic minorities that are not known to be loyal supporters of the party are banished (or even killed). * Result: Whoever controls the highest level of the party, controls what thoughts are allowed to be expressed in public, and controls who hold positions of "power" in the government. This system had multiple strategic vulnerabilities. The tendency to prevent non-party endorsed ideas from being heard handicapped innovation, commerce, industry, agriculture, and the military. This tendency often resulted in conflicts with other military powers, and sometimes caused the country to be isolated diplomatically and militarily. This system had two legalistic vulnerabilities: If a reformer captured control of the top level, they could push through constitutional changes. Also, these systems generally made a point of continuing to hold regular elections, where the populace could only vote for party-supported candidates. If a group of candidates could somehow get on the ballot, indicate to the public that they supported reforms, and prevent vote-fraud, they could win the election. [Answer] Some possibilities are raised by the game Alpha Centauri, which has future government types "Cybernetic", "Eudaemonic", and "Thought Control". Cybernetic: decision-making turned over to computers. This has been attempted and failed ([Project Cybersyn](https://en.wikipedia.org/wiki/Project_Cybersyn)). Perhaps it would succeed with better technology. When people have self-driving cars and self-restocking fridges, and most business decisions have been turned over to computer, having to make policy decisions by mere talking seems inefficient. Eudaemonic: explicit policy focus on maximising human happiness. There are occasional attempts in this direction (basic income, "gross national happiness"). Thought control: it's a lot of work to give people what they want. But if we can make them want what they're given, everyone can be happy. This might start by greater control of information, propaganda and advertising and lead into full brain-implant mind control. (That game's help text constitutes a serious work of futurist fiction in itself, influenced by *Red Mars* etc.) [Answer] We may be seeing a return to "Ruling king with parliament" governments. In these systems: * The king is happy to have the firm support of one-third to two-thirds of the population, as long as the remaining population is not organized to overthrow him. * Parliamentary debates and decisions matter. Cabinet ministers can be forced to resign if the parliament concludes that they are corrupt or incompetent. * The king has honorably served in the military, and the soldiers consider him (and his heir) to be one of them. * The king is in charge of the military. * The king has enough say that all cabinet ministers must have his confidence and approval. * Royal succession is hereditary. Succession crises are resolved by the royal family putting forward an heir, and the parliament ratifying the choice of heir. Some countries that have such governments, and/or are likely to have such governments after current civil wars are resolved: * Morocco * Jordan * Kuwait * Syria (currently in a civil war; the ruling faction has about 10% of the population) Countries that could adopt such a system: * Russia (if it chose to have a Putin descendant succeed him) Most Western European countries have "reigning" monarchs, not ruling kings. But if their peoples conclude that their systems have failed them, and that their princes are up to the job of being ruling kings, then Europe could also have ruling kings again. Current fiction works that provide detailed descriptions of transitions toward such a system: * Tom Kratman's *Carrera's Legions* series. [Answer] The short answer is that it depends on what happens to change the status quo. Democratic forms of government (rule by popular vote, either directly on matters of state or indirectly to elect representatives) typically fail either when the process is perverted by those in power in order to remain in power, or when two or more demographics cannot agree on a common path for the country and a substantial minority refuses to accept majority rule. Both have been seen many times in Earth's history. The second situation's outcome is well-known; the minority either tries to seize power by force, or if they're geographically grouped, they try to take their land and leave. Succeed or fail, you basically end up with one ruling party and no opposition in either one or two nations. If the democratic process is subverted such that the masses no longer have a free choice of their representatives, either because elections are discontinued or the vote isn't free or fair (for instance, some people get more votes than others, or every candidate has the same plan to govern ultimately provided by those who *really* run things), the democracy devolves into a plutocracy, governed by the wealthy, who gain power through their wealth and wealth through their power in a self-perpetuating cycle. There are dozens of dystopic visions of the future world along these lines, where ultimately government is controlled by business interests, or a few oligarchs, or even a faceless super-conglomerate. Plutocracies can further devolve into an autocracy (self-perpetuating government by a single person), or either a plutocracy or autocracy can persist indefinitely. These are generally considered "bad" in current Western politics, but there's a dualist nature to their perception in Western fiction, based on part on feudal rule of most of those same societies as recently as a few hundred years ago. Exactly who or what the ruling entity is, how they act and the amount of prosperity of the average person under their rule sets the entire tone of the story. If the democratic process remains effective, as a society develops technologically and economically we tend to see a trend towards socialism in the far but not extreme left of the political spectrum. This generally occurs as more and more services previously only available to the very wealthy are recognized as essential or "basic" to the functioning of society (running water, electricity, mechanized transportation, voice communications, data transfer, healthcare; all of these were at one point considered a luxury afforded only to the wealthy elite), and society as a whole enacts rules guaranteeing availability of these services to the lowest common denominator, to the point that nobody in the private sector sees any profit in continuing to develop it. Government then steps in and asserts primary authority to administer and maintain the infrastructure for the service. Power ultimately rests with the well-connected and charismatic elements of the society who gain power by being well-liked and likable. Probably the most well-known extreme of a socialist society would be Orson Scott Card's Ender universe; Ender Wiggin's brother Peter is basically elected ruler of the world through social media, not dissimilar from choosing an election based on who has the most Facebook followers (which would, right now, be [Cristiano Ronaldo](https://en.wikipedia.org/wiki/Cristiano_Ronaldo)). The society has its ups and downs, especially in the early books; there are things done to and by Ender that are horrifying, such as the ultimate violation of the right to privacy in the form of a neural implant that gives his supervisors a direct audiovisual link to what he sees, hears and does. Population control measures that basically require a lot of greased palms to have more than two children are also things most free societies today would frown on. Overall, however, most people live as they choose, and have a wealth of technology and information at a wave of their hand. [Answer] I would say that a government controlled by **Artificial intelligence** seems quite likely (making the assumption that World War III will take place) 1. Inequality between countries is gradually increasing. Some economies are progressing and others are collapsing. US has sent Voyager satellites to the edge of the solar system, while three-fourths of the countries are yet to send a probe into space. International peace-keeping bodies like UN and WB do not give equal representation to all countries. 2. Humans are becoming more powerful by the day. The sum of power of all individuals in the human race is increasing. This is especially true in warfare. 100 years ago, we fought on foot. 75 years ago, we invented and used bombs, planes and chemicals. 50 years ago, we created the nuclear bomb. Governments are highly secretive on such issues, but it isn't hard to imagine how advanced today's nuclear weapons could actually be. 3. Conflicts are happening even today. Lesser people may be dying today then during the world wars, since we are not at war yet, but chances are pretty high that it could start any time between now and 50 years later. 4. This would lead to murder of countless lives. And to unification of various countries for the sake of survival (in the war, as well as after it). Though some may make attempts to retain democracy, chances are that only a few will be successful. Quite a few will have dictatorship, or similar governments in the name of democracy. 5. Computers will be extensively used by then for war strategy, to do everything from giving orders for supplies, to reading people's expressions from their political statements. It may go as far as the computers directly controlling the army and fighting the war. 6. In my opinion, it is likely that human population would drastically reduce. If an apocalypse does not occur, we will end up going back to dictatorships, except that the number of independent countries will be lesser in number and larger in area. Peace may be temporarily restored, but weaponry would become way too powerful for people to resist using it. 7. The world would be quite unstable as a whole. The only way to restabilise seem to be: * Rule of computers * Destruction of current technology and majority of human race * A global dictatorship by individuals with weaponry more advanced than the rest of the world [Answer] The liberty of the individual person comes from their power; power flows from both the barrel of the gun, and from one's economic utility. Automation takes off. Task after task becomes cheaper to automate than to employ someone to do it. When it is cheaper to build and maintain a computer or robot to do something than it is to feed a human, the human is absolutely non-price-competitive. The economy continues along, as task after task is eroded from being "worth" maintaining a human to do. Those with ownership rights over resources have fewer and fewer "selfish" reasons to employ humans. Personal service is one such area (including things that humans desire from other humans directly). The tasks that remain difficult for automation to do (whatever they turn out to be) also employ people. Depending on how hard those jobs are to do and network effects, their salary either skyrockets or plummets as many people compete for the job. Raw resources to maintain people compete with resources for computer/robotic industrialization. We can see this today, where Ethanol based fuel competes with the price of food. With higher efficiency solar panels and bioreactors, farm land for food competes with energy production more directly. Initially people will try to avoid having mass starvation. Welfare solutions, or make-work projects, or a myriad of other solutions are proposed. Unrest still occurs, as it sort of sucks to be on make-work and welfare. With the economic utility gone, and increasingly effective mostly automated policing and military, the power of those dispossessed shrinks. Divide and conquer politics follow in many areas, where the dispossessed are demonized for their very existence. In addition, wars in foreign areas, where the local underclass is dislocated by a automated remote war machine for their resources to be claimed. Some states maintain that welfare state. Others let it fall, and start dealing with their underclass in increasingly brutal ways. Democracy's legitimacy comes from its ability to claim the power of the masses as a source of legitimacy: with an automated police/military/production/trade system, the masses *lack power*. Democracy gets curtailed. Those democracies that don't bend, are broken; they are either passively out-competed by the leaner, more efficient states that don't bend to the masses (and get progressively poorer, as their trade balances collapse; the state needs to spend 3x the resources to make things that other states need to because they spend 2/3 of their resources on feeding the unproductive masses!) Note that none of this requires "true AI". The existence of a relative handful of people guiding the "not-true AI" computers/robots/etc doesn't change the shape of the situation much. Various stable governments result. 1. Utopian nearly work-free democracies. Increasingly inefficient due to the relative dead-load of the mass people. What human labor is needed is easy to source from a relatively large fallow population. 2. Brutal automated plutocracies. A handful of well-off people, with a relatively small number of elite workers, and a mass of oppressed poor. 3. Fake Utopian plutocracies. They pretend to be #1, but are #2. Propaganda convinces the citizens that they are "free" and "the best place to live on Earth" and "their vote matters". 4. Brutal automated wastelands. The end state of 2, as fewer and fewer of the elites have an "acceptable" standard of living, and even the plutocrats find their standard of living eroded by competition. Something like "Economics 2.0" takes over: resources are efficiently allocated by algorithms that provide less and less surplus for human well being. Humans are trained to provide solutions to the problems that the (probably not true AI) cannot solve, and are rewarded with just enough resources to survive. Even "useful" Humans that consume more resources than that are punished by distributed algorithms that they don't personally have the permission to change, even if they hack the resource distribution engine to allocate more than their fair share. May collapse in the long term. [Answer] ## Today : Democracy (really?) Most elections on democracies those days resumes on a marketing race where the candidate with the bigger budget and better media exposure wins. People are not really interested on whats happening in the backstage and most even don't cares if they are getting they paychecks and buying the last "you-must-have" gadgets. One can say consumerism is at the top and even candidates for representatives positions are products to be consumed by the masses. This scenario makes candidates prone to big donors (banks & corporations) and to demagogy the most likely to being elected. The donors contributes to both candidates (in a bipartisanship way). No matter what puppet wins you can pull the strings on both of them. ## Optimistic future: [Wikicracy](https://meta.wikimedia.org/wiki/Wikicracy) Most likely to start in small well organized countries like Iceland this form of government uses all advantages modern communication systems to create an [open environment](https://en.wikipedia.org/wiki/Open-source_governance) where citizens participate in the day-to-day political affairs. This way everyone can post on vote on new propositions most likely in a SE site (like WB for example). Also an wiki-management can greatly increase transparency in the government expenses and even improve wise-costs of public services. ## Pessimistic future: Cyberpunk dystopia Corporations influence in governments increase to (beyond actual) obscene levels and in practice starts to replace the government even in strategic affairs. Health-care is the first to fall but not the last corporations lobby put puppets in key places. Those degrade public services like the Police Department, Fire Department, Education, Mass Transit, Water, Power, everything. Outraged citizens incited by news fabricated in the backstages of power demands better services. Year after year government fails to meet populace expectations and when those services are sold to the corporations citizens feels relieved for a brief period. Unfortunately few can pay for all these services and society starts to stratify in castes but with all the media in corporation control the average Joe is most concerned about it's most favorite show characters life or the last sport league results. [Answer] I think what is going to happen is that online polls take preference. Take the referendums in Scotland about independence. Or the referendum in the UK about the EU and the Euro. More and more governments are giving the choice to the public so that they cannot be blamed for the outcome. I.E. they are not debating the issue, simply giving the choice the the general public. Therefore I think this is more likely. [Answer] While you could argue rather or not it constitutes a 'new' government, or just an expansion of the existing one, I have asked two [previous questions](https://worldbuilding.stackexchange.com/questions/23522/what-would-be-the-most-viable-hybrid-democracy-to-create-if-effective-instenanio) about how to create a hybrid of direct and Representative democracies which feels like a very new take or the existing democracy, perhaps counting as it's own form. The linked question addresses some of the concept, but let me go into detail. The idea is that with the internet we are capable of near-instantaneous voting now, making a direct democracy more fiesable then it has ever been before. Of course currently voter fraud and hackers are an issue with online voting, but we could presume in the future these are addressed and a system can be created which is no more prone to such fraud then modern voting, and that internet access has grown to be such a staple that it's presumed to be available to even the poorest citizen. If this is the case we can start to craft a system which allows voters to more directly express their wishes by voting directly on important issues. The advantage to a more direct vote is that votes can be more representative of an individuals opinion, where as it's impossible to pick a perfect representative that truly represents your views. Maybe you mostly agree with political party X, but your views on abortion are opposite of the party line and you have a slightly different view on the appropriate level of gun regulation. You pick the senator from your political party because you agree with 85% of that parties views, but that means that you picked someone who is going to do his best to make abortion laws that are the exact opposite of your moral views. You picked the best representative you could, and still can be upset that your views on abortion are not being reflected. With a more direct democracy you can vote along the party line for the 85% you like, and vote against them when it comes to abortion, better representing your own personal beliefs. f course the problem with this is that voters don't have the time to vote directly on every issue. a pure direct democracy would be ruled by those that took the time to vote (like the elderly) and would thus leave a huge percentage of people unrepresented. Already most only vote for president, even picking a senator is rare, but that is only one decision every few years. Imagine if you were asked to make a decision every day, few would do it, making those who did quite powerful. Thus you create a hybrid solution, with representatives picked by voters who actually manage most votes for a voter, but with the voter able to personally vote on any law or legislation he chooses as well. My question went further to suggest the idea of voter blocks and a sort of hash-tag approach to voting. Each voter can pick a representative to represent them for certain types of votes. For instance you may have someone who believes in small government with little overhead (like republicans) but in more liberal 'if it isn't hurting me let it be' social policies, like the democrats. He may pick a republican 'fiscal' representative and a democratic 'social' representative, who will vote according to his views. Social matters thus get one vote and fiscal a separate vote. In reality things would likely grow more complex, with one voter able to grant his voting rights out to many representatives. To make this work imagine a system where each bill is given a number of, well frankly government standardized hash tags, to represent the content of the bill. The bill to increase taxes and move the money into supporting faith-based charities may be tagged as fiscal, but with a sub-tab of religion and 'government-support' (some tag similar to welfare, but with a more generalized meaning). A voter can assign a representative to represent a tag he cares about, but he gets more flexibility then that. This system requires a vote to be divisible, one vote may be infinitely divided. So our theoretical voter who preferred small-government may have chosen the small-government fiscal representative. However, he may also be very devout and so for the religious sub-tag he picked a strong "christian rights" representative. For this vote his fiscal voter may vote no for the bill, taxes mean big government, but his religious representative may vote yes, more money to faith based initiatives help them to do god-work. One vote each way effectively nullifies his vote, and so his vote doesn't work at all. However, he may have more flexibility in how he assigns his votes. Maybe he chose the fiscal rep as his main voter, but set it up so that in times where it conflicts the religious rep gets priority by representing 2/3 of his vote on religious bills. The fiscal rep votes against the bill, with 1/3 of the voters granted vote, and the religious rep votes for it with 2/3 of the voters proxy vote, leading to that voter voting 'yes' with 1/3 of a vote. Modern vote systems can easily handle such fractional votes, enough 1/3 votes can counteract full votes... Of course perhaps in this situation our voter feels that it's a bad idea. He figures that the letter of the law means that christian groups could not use the extra funding from the government to actual preach or evangelism, so the law doesn't help him spread his religion and, to him, is just another form of welfare. So he decides to vote directly against the bill, taking back his proxy vote and directly voting against the bill. He can, at any point, do this, his representatives are simply a way of voting by proxy for the votes he can't be bothered to vote on directly; he always has the right to directly vote personally on any bill he considers important enough to vote on. That's the short idea. This will result in a very different feel, with a decrease in power of political parties as instead of voting on specific large platforms voters can focus on personal belief systems. However, complex politics will start to be about how to assign the 'tags' to a particular bill in order to get the 'right' representatives to vote for the bill, ie the ones you think will vote in your favor. For example, say there is a a vote being made about rather to fund abstinence based sex-education or to fund only comprehensive sex-education. Perhaps those that want to pass the comprehensive sex-education bill will try to get the "LGBT-rights" tag assigned to the bill, on the grounds that comprehensive sex-education is more likely to address alternate sexuality and therefore pro-LGBT representatives would therefore be more likely to vote for the bill. You could argue rather sex-ed really is an LGBT-rights issue, but rather or not it gets assigned to a bill is partially based off of rather one group or another thinks those reps will vote in their favor. Sadly you can't get the politicking out of politics lol. Notice I've refereed to finance votes in a way that isn't really representative of how bills work currently in the US, that's intentional. In this new system there would likely be a focus on breaking up larger decisions, like funding decisions, into a number of smaller votes so that people can better vote on them individually; which would also require a focus on less time debating each bill if you want *anything* to be done, or perhaps just more parallel votes going on in different sectors, the 'financial' and 'social' votes can happen mostly independently since reps for one can vote separately from reps of the other. Of course this addresses only the votes. Someone has to craft the original bills and votes. Thus I imagine a representative will be picked the way most representative democracies do who is responsible for crafting and modifying bills, and this rep's vote would count for anyone who has not transferred his voting proxy to another representative. The difference is that when votes happen multiple voting representatives can vote along more complex divides then just bi-party views. I imagine one of the biggest bit of politicking in this system would be how to assign 'tags' to a given vote. A group may try to get certain tags attached to a vote because they know that the majority of voters for that tag will vote along the lines they want, so bickering over what tag to assign or not assign may become quite common. This is assuming that the government assigns tags. As an alternative there may be non-political entities that read and assign tags and someone may choose to use any one of a few 'tag assigning' entities as the one that decides how to tag a bill to decide how their vote proxy should be divided. Obviously this system only works in a modern world with computers. This would all get way to complex without not just instantaneous voting, but also the ability to help calculate complex rules for how a single vote was divide. However, with modern computers these sort of calculations can be done easily. All a user has to do is assign his vote proxy using what would amount to a simple rules-engine to best define how he wants to divide up his vote amongst representatives. Most will assign their vote to a single rep, some will assign their vote to a single rep but with one or two issues that are important to them getting special reps, and only a few will right more complex rules for vote proxying, but every voter gets to decide how they wish to divide up their vote, and every voter gets the right to personally vote on an important vote if they choose to. \*note, these theoretical voters do not necessarily represent my personal political views, I'm personally a registered independent without strong preference to either party. I added views as I came up with a good example that would require someone having a certain view that's all. [Answer] Perhaps we will see experiments with [demarchy](https://en.wikipedia.org/wiki/Sortition). Demarchy has been described as *democracy without elections*. We will still have a parliament, but its members are *randomly* selected, similar to members of jury in jury systems. A small experiment was done in The Netherlands with the [Burgerforum Kiesstelsel](https://nl.wikipedia.org/wiki/Burgerforum_Kiesstelsel)[NL], but its recommendations were ignored. Considering the limitations of democracy you describe: > > The disproportionate influence of people and corporations who can afford to hire lobbyists and donate to campaigns. > > > Lobbyists will still influence parliament directly, as they do now, but there will be no more campaigns as there will be no elections. > > The fact that you can only choose the "least bad" option. You may agree with some policies but not others but the only choice a voter gets is one package or another. > > > A sufficiently large randomly selected parliament assures that all preferences are represented equally. > > A high risk of corruption in general since the power is concentrated into the hands of the representatives. > > > This may remain, although one might wonder if randomly selected people are more or less corrupt than politicians. > > Under-representation of minorities. > > > Minorities will be more or less represented according to their share of the population. One risk is if a large group of a minority is disproportionally considered unsuitable for political duty, due to being a minor or not meeting “objective” (i.e. Jim Crow) requirements. > > Short term thinking driven by the need to get re-elected in a few years. > > > Nobody will need to be re-elected. > > Can result in an elitist political class passing power back and forth between each other. > > > This is eliminated in demarchy. There are plenty of disadvantages, as all systems do. But to answer your question: Will it actually happen? Probably not. But who knows. As [Niels Bohr is disputedly reported to have said](https://en.wikiquote.org/wiki/Niels_Bohr): > > Prediction is very difficult, especially about the future. > > > [Answer] The primary issue is the dissonance between Politics and Governance. Politics is defined in Organizational Theory as a means of allocating resources. (We often talk about office politics as being why so and so got the corner office, for example). The issue in the present and near future is that most people in the developed world have access to more than enough resources and really don't need government or the formal political process to do much more than ensure that they are protected and can keep their resources (an army and police) and there is a neutral means of arbitrating disputes (Courts of Law). This is sometimes called "Libertarianism as a Social Movement". New technologies that increase productivity, allow you to do more things with fewer resources (compare a Smartphone to the plethora of devices we needed to do the same things when the PC was introduced in 1981) or even disconnect from the grid (while not totally possible just yet, there are a lot of technologies that can get you pretty close). A person living that lifestyle isn't going to need or appreciate someone interfering with their lifestyle with more taxes and regulation. OTOH, governance (the art of the possible) also includes many mechanisms that reward increasing the size and power of the State. This is sometimes summarized by Pournelle's "Iron law of Bureaucracy": > > Pournelle's Iron Law of Bureaucracy states that in any bureaucratic organization there will be two kinds of people": > > > First, there will be those who are devoted to the goals of the organization. Examples are dedicated classroom teachers in an educational bureaucracy, many of the engineers and launch technicians and scientists at NASA, even some agricultural scientists and advisors in the former Soviet Union collective farming administration. > > > Secondly, there will be those dedicated to the organization itself. Examples are many of the administrators in the education system, many professors of education, many teachers union officials, much of the NASA headquarters staff, etc. > > > The Iron Law states that in every case the second group will gain and keep control of the organization. It will write the rules, and control promotions within the organization. > > > The sorts of authoritarian people drawn to these kinds of organizations will also be quite envious of the wealth that is accumulating on the outside, and try to bend rules, regulations, taxation and laws to channel the wealth towards them, and insulate themselves from the worst effects of their actions. Sine even in the most utopian world there will always be a need for the minimal functions of governance (protection of liberty, property rights, the rule of law), there will always be an "in" for the Iron Law to take root and grow. It is difficult to imagine how a controlled drawdown would take place, but societal collapse, armed revolution and other forms of destruction of the regulatory structures and institutions tend to leave dictatorships in their wake, rather than the freedoms revolutionaries imagined. In the short to medium term, I suspect the most likely form of "post democracy" will be in the form of people taking themselves out of the loop and moving to secure their wealth and property in ways that governments can't tax or expropriate. This could range in form from growing "victory gardens" and otherwise getting off the grid to moving to cryptocurrency and dark "mesh nets". People living in these circumstances will form associations which will be more tribal in nature, bound buy shared affiliation and mutual trust, and loosely interacting with other "tribes". If governments prove ineffective at providing protection from external enemies or criminals, then these tribes will also evolve to take on these duties as well. So "post democracy" might not be feudalism or Mad Max, but it won't be pretty either. [Answer] Maybe, online democracy with people voting in the Internet on many issues including minor ones, such as placement of bus stops and what to be offered in local supermarket. [Answer] ## Rule by Machine Learning Most people today assume that AI would be an intrinsically inhuman form of government, but in today's schools, learning about Machine Learning is becoming compulsory in more and more fields of study each year; so, soon enough people will understand Machine Learning well enough to give wide scale political support behind replacing human leadership with AI. Machine Learning would allow for a form of government that is even more representative than direct representation. People only know what we want, but can not understand how our wants will lead to things that we either do or don't like. If a local ordinance is proposed to allow a casino to open up next door to us, how do we know if we should vote to allow or disallow it? Under democratic rule, we only know what various forms of media tell us, and those avenues of information are curated by people spending money to manipulate our vote, but with machine learning, you can cut out the manipulations. By analyzing our online information, an AI is able to classify a person into a variety of cohorts which defines how we are alike and different than other people. Using cohort correlations, AIs can than make predictions about us that we can not even make ourselves. If 95% of people who like cheese are pro-casino, and you like cheese, then the AI can factor that into voting for you as to if you will be satisfied with the new casino. You don't have to understand what being a cheese lover has to do with casinos as long as the correlation is high enough, it tends to be a good predictor. But this is only 1 part of what Machine Learning can do. While democracy makes adding rules easy, it is very hard to roll back bad decisions in a democracy due to the shortcomings of human nature, but a Machine Learning system can analyze public opinion in real time; so, if everyone seems to want the Casino before it is approved, and then the AI realizes that the casino is destroying the local economy making a lot of people upset, it can resend its decision without getting stopped up by concerns like saving face, sunk cost, or other hang ups that prevent humans from changing thier minds in politics. This leads to the 3rd strength of Machine Learning: It remembers every failure its ever had. Humans only know what we know, and in democracies, we are constantly replacing people who've learned from thier mistakes with new people who have never made those mistakes before and therefore do no know not to make them. So if the AI knows that every time it approves a new casino, that this is followed by a 10-20% drop in approval, then it knows not to approve a new casino even if there is 60% support for it based on the cohorts composition of the local population. [Answer] **Plutocracy/Technocracy.** First off, let's assume current trends of today continue. Corporation grow in power and gradually vie to exert more and more influence over politics than they do even today. Eventually, after years of decline, government assets, services and properties atrophy and are bought by companies. However I actually get the feeling that the US military might remain one of the few intact and in power institutions alongside a few other organizations given that modern PMC's are never as competent as their government equivalents. What we see basically is a transition to something resembling the government of an old merchant republic. By now the old democratic government has become so atrophied that it resembles a glorified HR department rather than a functioning entity. Barring certain changes, it'll probably be very bad news for the average person given how worker's rights tend to go in these types of societies. We'll see of course a new aristocracy and power structure. With a ruling class composed of shareholders, bankers, CEOs and Junta officers. They'll also work alongside a sort of middle class. Imagine the modern equivalent of a medieval guild basically. The bureaucrats, engineers, doctors, scientists, managers, popular celebrities and educators. Atleast the ones that exist at the top of the totem pole. Alongside them will be of course be police, military and heads of intelligence agencies that have been coopted. --- Now this society won't spawn out of the ether or due to some corporate overthrow. Rather it happens gradually due to current trends refusing to ease up. With voting becoming useless outside of local politics. People feel the need to vote for strongman politicians and selected oligarchs who make the problem worse rather than easing their frustration. The current civil-military gap also widens deeply. Unrest and crises boil over, and more funding is placed into policing and controlling that unrest. Eventually democracy becomes picked clean via a slow and steady series of reforms and changes. One year, company towns become legalized. Another year funding for public libraries gets cut. News laws are put in place to make voting requirements more stringent. Mayors and governors become obsolete as pretty much everything, from parks to post offices are bought out and they find they no longer have any say over property that doesn't belong them. Worker's rights get trampled. In particular the Plutocracy begins to clamping down on worker mobility. Via blacklisting, occupational licensing policies and non-compete clauses, as well as control of vital amenities like healthcare and housing. Even basic services, like grocery stores that sell fresh food might all become membership only clubs that you have to pay for or receive a membership from employment. Leaving you stranded in a food desert if your unemployed. Throughout this all, everyone in power will deny being an oligarch. They will still chatter on about democracy and freedom. However slowly the message will start to change. 'I love democracy and am not an oligarch, but even if I were would that really be so bad?' In other words, media and art will gradually start denigrating democracy and all its ideals without ever outright using the word 'democracy'. Things like workers rights and public services become ridiculed or vilified. Victim blaming of the poor for their helplessness becomes more common. Movies and media will typically be hideously classist by our standards. With media often times giving false platitudes and advice to the average person. [Answer] ## More pervasive democracy within ideologically aligned communities The current situation is at odds because people depend for livelihood and all the essentials of life on corporations or other authoritarian structures, which may be nominally democratic among shareholders but almost invariably operate as fiefdoms. A future society has cooperative enterprises everywhere, acting in nominal competition that is softened by some weakening of the profit motive. CEOs have gone the way of the dinosaur. Lobbying has fallen into the hands of ordinary men. Social classes have broken down and a deep sense of equality pervades a society where people can move into new employments more easily and with much less sense that this is what defines them. Yet from among all these voices, fundamental principles emerge. The Bill of Rights is many things -- *short*, mostly -- but people are changing that, and with it, establishing new definitions of community. In a sea or space settlement, community may have nothing at all to do with *place*, which changes constantly, but only on *principle*. Over time these principles, seen as inalienable rights rather than positive law, tend to supplant ongoing democracy within any given community. War is replaced by a struggle to win immigrants. [Answer] As mentioned here, you have things like the civil oligarchy that many say the United States has become:" [the only type [of oligarchy] in which no oligarchs rule (if they hold office, it is never as or for oligarchs), and the coercive state defending property for oligarchs is governed impersonally through bureaucratic institutions"](https://www.cambridge.org/core/books/oligarchy/civil-oligarchies/86DDCA90915EAF82AB028F8FAA0949E6). You can also have [bankocracy](https://en.wikipedia.org/wiki/Bankocracy) where the financial institutions of a nation have control. There are examples of this in history and people have talked about bankocracy in Europe during the 2007-2012 financial crisis like Economist [David McWilliams](https://web.archive.org/web/20110114215911/http://www.davidmcwilliams.ie/2011/01/12/citizens-must-fight-rise-of-european-bankocracy). There is also direct democracy replacing representative democracy, something that has already happened in [Switzerland and Iceland](https://politics.stackexchange.com/questions/27842/which-nation-is-a-direct-democracy-at-the-national-scale) which are both nations with direct democracy. The popular vote allows people to make direct decisions in governance. Another possibility is [algocracy](https://doi.org/10.1093%2Fcomjnl%2Fbxy082): a form of government where the usage of algorithms, AI, and technologies like blockchain, is applied to regulate society & enforce the law in day-to-day life. Some versions of this have been tried practically in real-life such as Project [Cybersyn](https://web.archive.org/web/20090910060602/http://newsinfo.iu.edu/web/page/normal/11088.html) between 1971 and 1973 in Chile & government auctions run by blockchain-based algorithms back in [2017](https://www.reuters.com/article/us-ukraine-bitfury-blockchain-idUSKBN17F0N2) as part of an experiment in Ukraine. [Answer] Long version: iVote replaces electoral college, and since it is owned by a Chinese conglomerate and not Diebold, it is met with great fanfare. Soon it is entrusted for all the things. Polls are taken before each meal. This leaves the government without politicians directors or undersecretaries, but with plenty of agents. The agents direction comes not from supervisors, but from the polls. At some point the apathy and fickleness of the voter is recognised by the agents. Warlords rise up from the agent ranks and fight each other over who will be the Agent-King. By this time the voters are not considered people, rather natural resources to be used for the good of the powerful. Soon Autokrator Constantine Augustus I installs himself as the Agent-King. Then, after declaring himself divine stud, he has sex with all the things contracts syphilis and dies. Short version: Monarchy. ]

[Question] [ # The Situation A colony of 100 teleporters (between the ages of 20-40) have been hidden away living like monks for 1000's of years to prevent their detection. With the death of their old leader, a young new leader takes control and wishes to push the colony out into society and break the shackles of the boring monotonous mountain lifestyle. The new leader has some very clear initial goals. In order of importance, he wants to: 1. Retain the absolute secrecy of the colony. No one must know that the colony exists or that they are teleporters 2. Do everything ethically responsibly1 and sustainably (this operation should be able to keep running even if he needs to step away for a few weeks) 3. Have each of the 100 teleporters make at least \$100,000/yr (or collectively have the colony make >\$10,000,000/yr) 4. The colony members must all be free during key times of the week, so time-sensitive jobs are only good if the time can be planned in advance. As the teleporters have been living in the mountains their whole lives, they don't have many skills to offer society. While the new leader considered having them work office jobs, after several brutal interviews he's decided the only answer is their teleportation. # The Teleportation Each teleporter has a finite number of base teleports a day before they become too tired to continue teleporting. This base number is found by having each member teleport a 10lb box 100 miles repeatedly. The colony members' base teleports range between 100-300 teleports/day. A teleport of distance $d$ miles carrying an object weighing $w$ pounds would use $d/100 \cdot w/1$ base teleports of the 100-300 (if $w \lt 1$, $w$ gets rounded up to 1). ie. A trip from San Diego to New York (~2700mi) carrying 5lbs would burn $2700/100 \cdot 5/1 = 135$ base teleports and would likely leave them too tired to teleport much more for the rest of the day. In practice this means a teleporter can make tens of thousands of teleports a day from the couch to the kitchen to grab a cookie, but could probably only make 2-3 teleports a day with a new car between neighboring cities. # Things to Note * The technology level (currently) is that of modern (real-world) Earth. * While the colony is removed from society, they have been keeping tabs from afar. A group of elites does scheduled reconnaissance--picking up newspapers and going to libraries to use the internet, so the colony has knowledge of the outside world. # The Question **What is the best way for these teleporters to make this amount of money ethically and sustainably while also keeping the secret about their teleporation?** --- 1. I've chosen "ethically responsibly" over "legally" given the audience here on World Building :) By this, I essentially mean avoid outright stealing or killing for the money. Clearly the books will have to be cooked and lies will have to be told to hide the teleportation. I'll be adding to this footnote to patch any other ethical loopholes found. [Answer] # Think Small Instead of moving items very large distances; why not move them small distances; it's not like you get paid per mile. You could almost entirely remove the equipment cost and drastically increase the speed of repairs for things like large trucks, ships, and even in-place mechanical repairs on large machinery systems. Instead of needing an expensive over head crane to remove the engine from say an 18-wheeler; one of your teleporters can teleport it 20 ft to the side onto a waiting stand. This changes a multi hour task of rigging; checking; and adjusting into something that takes an instant. Moving 100,000 lbs 10 feet would use approximately 1.9 base teleports; your mechanic would not even have a bead of sweat when they are done. Or while working on a machine there is a part that would normally require hours of unbolting other pieces to reach. Instead a teleporter can touch the part (I assume they have to be touching it to teleport it) and *poof* it onto their workbench. Reverse the procedure to install it. This case is very ideal since you are moving small parts (<10lb) tiny fractions of a mile (5ft is about 1/1000 of a mile). Mechanics shops for cars in the us can charge around [80 dollars per hour](https://www.local10.com/digital-life-365/automotive-essentials/why-do-mechanics-cost-so-much) for labor; but if you work on specialty items such as large marine diesel engines the rate can go into the $100's/hour. You would be making the same money as normal shop from mark-up on parts and labor rates; but you could do more jobs in the same amount of time and without needing to maintain large expensive equipment; although you still would want to have the equipment in the shop (maybe buy it second hand and broken) just for appearances. Sure your colonists will need to learn many new skills; but they will have a major competitive advantage that no-one could compete with. The best parts are: * No Ethical/Legal/etc. issues * 100% legitimate business, you don't even need to cook the books! * Low chance of getting caught (all teleports happen behind closed doors) [Answer] First of all they should only teleport things, not people. People talk. Otherwise, **they're in the shipping business**. They should use their teleportation ability to mimic real world transportation so as to avoid any suspicion. For example If they are supposed to teleport something from A to B that it would take a month to get to B then they should still make sure the things they're are teleporting still only arrive at B in a month. So how does that make them better than say a cargo ship that takes a month to get to B? A) They could still shave off a few days, say a week in this case, to beat out the competition. "No one can beat our fast and safe service! Your items will arrive where they're supposed to be days ahead of schedule and in perfect condition!" B) They could charge a little less than other shipping services too. So they're faster, safer AND cheaper? How can you beat that?! C) They could charge a little more for their unique "Overnight" service. "If it has to be there tomorrow it will be!" D) They could also form a very exclusive partnership with the largest company in the world (Amazon?, Walmart?) and work specifically for them. "No one knows how they do what they do in that warehouse, but man their track record cant be beat!" "Yeah, as good as they are I don't care how they do their thing!" They'd have to cook up their "books" to make it look like they're spending the way ordinary shipping businesses do, but even that is only slightly shady since they are doing what they say they're doing. It's a lightly grey area business at worst. **Bottom line, they're in the shipping business and they're the best at it**. EDIT: I thought I'd throw this in here since it's getting so much attention in the comments below - Concerning tracking device: That's easily countered with double and triple checking the items to make sure they are NOT tracked with a tracking device. "What tracking device? We weren't aware. We're sorry you don't trust our shipping service. If you have any safety concerns please feel free to refer to our customer service department. However I would like to stress that your item(s) did arrive at their correct destination, ahead of schedule and in perfect condition. Thank you for your business." Plus, the more plausible answer than teleportation is that your tracking device malfunctioned. Thanks [Answer] **Cocaine** /end thread. They could do it ethically by bypassing the cartels entirely. Farm to glass table, if you will. The growers in S. America make more money and nobody gets killed. **Asteroid Mining** With a good telescope and a stolen/borrowed space suit, they could pop into space, grab a chunk of iridium and be home in time for lunch. They would make *way* more than 10 million. **Tuna Fishing** A fresh Tuna is worth thousands. These guys can deliver them still-wriggling. Without the stress of being caught, their tuna might taste the best, too. **EMT's** They could respond to medical emergencies instantaneously. Anyone who gets injured could be in the ER in the time it takes to forward a phone call. This would save an *awful* lot of lives. In health care, there's this thing called 'The Golden Hour', where, if they can get you in front of the doctor in less than an hour, your chances of survival are astronomically higher. Teleporters could get all their patients to the ER inside that golden hour, saving lots of lives and making boatloads of cash while they are at it. An ambulance ride costs around 10,000, and teleporting is *better*, so they could charge more. Ohh... you said secretly. That makes it harder... [Answer] ## Secure Data/Info Transfer A backpack full of hard drives moved instantly from point to point. 100 TB from NY to LA in 30 minutes. Like a courier service combined with a logistics company on steroids. Two professionals come to your office, pick up the items and take them to their armored car, where one blinks back to a local office, then gives the drive/data to the long haul traveler, who takes 5-10 across the country to the other local office, where another milk run transporter blinks from the office to another armored car parked outside of the recipient's office. The drivers are following a milk run route pattern, while the transporters are following a hub and spoke network. The hub and spoke system would probably be faster than the armored cars, so there would be time to consolidate loads for the long haul trips. If the average transporter needs to generate \$400 in revenue per day and can carry 20,000 mile/lbs, the minimum cost is 2 cents per mile/lb. Doubling that to account for some overhead, 4 cents per mile/lb means that moving a 10 TB drive 1000 miles in say, 2 hours, costs \$40. AWS charges \$87/TB of one way transfer, and that's about the cheapest you will find, plus the cost to move the data in and maintain infrastructure. Transferring 10 TB at 1 Gbps will take over 24 hours. Increased speed and security make this a premium service, so 1 hour rush service could charge \$1.00 per mile/lb (slightly more expensive than AWS, but 25x faster), while 2-3 hour standard service could charge \$0.50, and 'no-rush' same day could charge \$0.20 (still faster than AWS, and 1/4th the cost). It would dominate bulk data transfer and long distance corporate courier services, and with that rush service, a single transporter could earn \$20,000/day in revenue, or \$4,000/day at the 'no rush' rate. --- **Edit** # Exploring the economics of teleportation Teleportation as described in this question boils down to the ability to instantly move a mass a distance. The unit can be lb-miles, and a teleporter can move 10,000-30,000 lb-miles per day. Freight haulers even use the term ton-mile when referring to cost to move freight, so in those terms this is 5-15 ton-miles. This isn't a huge volume of freight, a tractor trailer can move up to a 40,000 lb load up to 600 miles in a day, or 24,000,000 lb-miles. 100 total teleporters also puts a hard cap on the size of the enterprise. There are all kinds of logistics and delivery companies, but teleporters have a few advantages: * the travel is instant, and * other constraints like walls, borders, traffic, and gravity don't limit the travel. Speed is useful for outrunning the competition, and for specific scenarios where speed or freshness are key. Fresh tuna was given as an example given by James. Data transfer, hot shot delivery, a courier service, and more all take advantage of the speed to compete with traditional businesses. Avoiding the constraints of gravity make asteroid or diamond mining possible, but there are other limitations. If the monk has to go to outer space to grab an asteroid and carry it home then they will need PPE, reducing their effectiveness. Mining has a lot of additional costs beyond moving material out of the earth. Avoiding border crossings makes smuggling viable, including moving state or corporate secrets. Being able to teleport through walls also allows entry to anywhere. If stealing and spying are out of bounds, there is the possibility to teleport into a doorless vault or void in a mountain, allowing extremely secure storage. If there are degrees of permitted surveillance, a private investigator that could bypass security and access files, place surveillance equipment, take photos, etc. Instant transportation of relatively low mass objects has three possible target markets: * As a service provided to a handful of organizations, like providing secure transport of documents for governments or corporations with long, stable contracts and not too many customer interactions. * Targeting a specific niche. Asteroid mining, owning a deep mine, or smuggling across a specific border all allow a fixed working location with very little outside interaction. * Service provided to the public, like Fedex. Strict security and controls would be needed to maintain secrecy, and a good cover story would be needed. A cover business could be built that might end up being more lucrative than the initial business as well. [Answer] Moving things into low earth orbit might be an option. You could make your ten million dollars with only a single delivery to the ISS. The space shuttle cost \$1.5 Billion per launch. Billion. [NASA is working on a rocket that only costs \$500 Million per launch](https://www.space.com/17556-giant-nasa-rocket-space-launch-cost.html). If they can move something the size of a car, even if they can only do it once a day, you're talking huge profits. ### If you have the option to tell one person Have the leader befriend Elon Musk, get him to sign an NDA, then offer to ferry some small things up, like fuel. He launches a rocket with a deep space probe with just enough fuel to get into LEO. Then you take up enough fuel to finish the mission. It takes a lot of fuel to launch the amount of fuel you'll need to get to Mars and beyond. The cost savings for Space X would be really big. ### To get around people discovering your secret This is how you get around people trying to figure out how you get things move from A to B so quickly and accidentally discover your secret: you announce to the world that you have invented The Teleporter. The box uses quantum entanglement to break the laws of physics and sends object at distance faster than the speed of light! It'll immediately get dismissed as a hoax, and any evidence that you are actually teleporting things will be taken as trickery. Now you can do whatever else you want to do in plain sight, and no-one will ever consider that you're actually teleporting stuff. [Answer] Hotshot transporting. For the uninitiated: "Hotshots" are unscheduled, emergency courier deliveries, typically industry related. Say an oil rig drilling in the foothills in Alberta breaks a hydraulic pump and needs a replacement right away. They call a hotshot company to pick up the replacement at a supplier and deliver it to the rig, whatever the time of day or night. Because of the nature of the business, many hotshots are small businesses, perhaps only a single person with a pickup. Their cargo tends to be small, and they're on call 24/7. Even a larger company offering hotshot services may contract out the actual work to independent drivers. This is ideal for your teleporters. All they have to do is have someone show up at the supplier with a small truck, grab the item, go to a hideout they run, and teleport the cargo to another place of theirs with an identical vehicle closer to the delivery site, which they then use to make the delivery. They putter around for a while before showing up with the delivery, slightly faster than someone theoretically could driving the whole way, but not too much faster. Say they were transporting a part from Edmonton to Calgary. A normal drive is about 3 hours, but they show up in two hours fifteen minutes. That kind of time is *possible*, but you'd have to be speeding to pull it off, not have any traffic or other delays, so on and so forth. So how do you make the money? First, you get a rep for fast delivery, which bring you business. Second, you save a fortune on fuel and maintenance: your trucks aren't driving nearly as much or as far. Third, you're more efficient. In the above example, if you were delivering a part from Edmonton to Calgary, at least half the trip is waste because you're traveling empty. If you can teleport the cargo, then after the driver teleports his cargo from Edmonton to Calgary, the vehicle is still there in Edmonton to handle other business; it's not tied up for at least 6 hours going to Calgary and back. Even your teleporter can get in on it. In the time they spend killing to pretend to be driving, they can also be doing other short jobs. Now, someone doing an in-depth audit would note that the mileage shown on the vehicles doesn't and gas expenditures add up, but if you're careful and pay taxes and follow normal rules, the odds of someone actually looking would be minimal, especially if your claimed deductions are truthful (you really only claim the fuel you burned). And due to the nature of the service, odds are no one would notice anything strange. [Answer] * *They cannot explain how they're doing* it, *whatever* it *is.* As Rekesoft pointed out, that prohibits any contracts where due diligence would want to look into their business operations. * *They cannot teleport outsiders.* The model explained by Legisey would leave too many people wondering. * *They cannot teleport into or out of areas under surveillance,* even if that was ethical and legal. They might get into problems if they cross borders without the right stamps in their passports. How about a "job" where the ability to teleport away from danger (or inconvenience) saves huge operational expenses, yet where only the end result is delivered to the customer? **Operate a [very deep mine](https://en.wikipedia.org/wiki/TauTona_Mine).** The mine will have conventional lifts and trains, and those are used to transport the ore, but people are not required to take that trip. All the people working underground are in on the secret. They can teleport from a staging area directly to the mine face, and return easily for rest breaks, or to bring down a tool or spare part that they suddenly need. [Answer] Medicine - You have a tumor that no doctor can remove, yet through word of mouth you heard about this monks that developed a secret ritual that removes tumors, people that want through it swear it works & as a medical procedure no one will bat an eye when you sedate the patient at the start of the surgery so he's asleep when he's tumor is magically teleported outside his body, and given the cost of insurance pay to every surgery the colony can make millions if properly managed... living like monks might actaully help their cover on this one. Manufacturing - if they are capable of teleporting individual atoms you got a [Molecular\_assembler](https://en.wikipedia.org/wiki/Molecular_assembler) at hands, a single sheet of [Graphene](https://en.wikipedia.org/wiki/Graphene) should be easy to create if you can take graphite (like the one find in a pencil tip) and split it to 1 atom thick layers and should pay quite nicely being a material that has a lot of potential yet one that current manufacturing techniques are expensive (I did a quick search and the cheapest I could find sold a 20X10 CM 25 micrometer thick 2 gram sheet for ~25$)... that being said corporate espionage is a real risk that your teleporters will have to watch for if they go this route. [Answer] Smuggling is the best option. If they don't want to deal with hard drugs, they can stick to smuggling other things. Illegal cigarettes are a big business in Canada and the US, being known as the best people to move packages without getting caught by police would net a few dozen teleporters more than enough money to meet their quota. Getting black market goods into countries that either ban them entirely or have hefty tariffs is another one. Alcohol going into various Muslim states, medicine into poorer countries, toilet paper and basic necessities into Venezuela, guns and equipment to dissident groups in any number of dictatorships, one or two drops a day by each monk would earn tens of millions of dollars at the end of the year. No one would know how they do it, just that they leave a list and down payment for the goods at a certain place and within a week it's delivered to another drop off point. This also allows them to set up their own schedule. If they need to set a certain day free, they just claim their main route has some extra border patrols, so it will take a little longer. Minor delays won't matter much as their service is far more secure and guaranteed. Edit Having six months to set things up would be good. They'll need to find a few people to act as go betweens until they get a good feeling for dealing with potentially violent people. This will cut into their profits, but getting some people who are in debt or desperate for help, will help keep things secret and ensure if anyone dies from a bad deal it probably won't be a monk. [Answer] # Outsourcing electronics repairs Some lines of trade are huge in certain countries, but smaller in others. This is due to differences in the price of labor. For example, in India, electronics repair shops are very common in cities. I lived there for years, and I have experienced this first hand. You can get a skilled and experienced technician to replace an obscure part of your smartphone, fixing the most amazing things, even if you don't have the most mainstream device. And (s)he may do it for just a few dollars (literally). Labor, even skilled labor, is significantly cheaper in India compared to other places. Conversely, in my native country of Norway, labor and skilled labor are extremely expensive. This means that the cost of repairing a phone is typically so high that most people just buy a new phone. Prices of consumer electronics vary little between countries, but the cost of labor varies greatly. Therefore, in Norway, you only have businesses that do simple things like replacing broken screens or batteries for the most popular devices, at a hefty fee. This is not even comparable to the businesses in India that can fix nearly anything for a small fraction of the value of the device. You set up an electronics repair shop in downtown Oslo or Tokyo, where labor is expensive. Customers come in with their broken devices. Their devices are teleported down to India or China, where you have a large repair facility with local skilled technicians. The technicians may believe the electronics are being transported by air or they may not know where they are coming from. The customers only make contact with the counter clerks, and believe the electronics are repaired locally. The monks can double as workers in the shops, as they can't be teleporting all the time anyway. Of course, you need to take normal precautions with customer data, such as backing up and securely wiping each device before sending it off, etc. Such things can be solved with similar routines as one would have with local technicians, and some trusted people to oversee the repair facility to prevent theft, etc. Advantages: 1. Smartphones are valuable but lightweight, meaning they can be teleported long distances. I haven't done the maths, but if the distance between profitable city-pairs is too great, you can use relays in between. 2. You'll be way cheaper than your competitors, and offer way more diverse service, both in number of brands and types of devices serviced and in type of repairs offered. 3. You can offer same-day service, fixing complicated problems in a very short time. 4. To stay ethical you could offer your technicians a higher salary than the local norm, while still keeping a good profit margin. 5. Since most replacement parts are manufactured in Asia anyway, you have easy access to them. If your repair centre is near a large technology hub in India or China, you can get parts for nearly any device you want in a matter of hours. 6. Your diversity and speed of service can blow your competitors out of the water. You may even have to limit it somewhat just to avoid raising suspicion. [Answer] **Response time, not transport.** Instead of taking advantage of being able to transport objects, take advantage of the teleporters' speed. Provide some sort of 'quick response' service claiming to have branches in multiple different countries. While you do in fact have branches in multiple countries, what people don't realise is that the John in your British branch is actually the Jesus in your Spanish branch, and also the Janvier in your French branch. By use of teleportation, you can call in backup from other branches almost instantaneously and simply claim to have far more employees than you actually do have. If you pick something where the incidents handled will be mostly unrelated (e.g. fire fighting, tech support, plumbing, electricals) and you simply state "oh yes, we have someone already in the area handling another call" then nobody will question your fast response time. [Answer] You want to branch out because no single business can generate 10 mio. without drawing some attention to itself, where someone wants to figure out how you are doing it - competition, journalists, fans or the tax people. Photo journalism can employ maybe 10-20 of your people. You can very often (not always, that is suspicious!) be at the spot faster than others, and reach places hard to reach, both for political and geographical reasons. Those pictures and videos can be valuable, and on the ethical side you can help bring the truth out. Building up some cover stories should be doable. Courier services are an obvious choice, but you want to focus on valuable documents only. They are light, need to be delivered in original for legal reasons, and you can deliver to countries where other people have problems getting visa on short notice. How exactly you do it can be a plausible business secret. This can employ 20-30 people before it gets noticed. Deep sea treasure diving is another example where 10-20 of your monks can actually do the actual diving, but being able to teleport around underwater would make the searching just so much easier. Beware of pressure differences and health effects when teleporting up and down. That's 40-70 people employed. You will need maybe 20 people for managing, accounting and such things, especially if you operate in multiple countries. Put the rest into odd jobs. A few magicians (easy to make various tricks if you can actually teleport, don't even have to lie when people ask you how you do it...) a few headhunters or private detectives. [Answer] **High Speed Data Transfer** Clients think you're sending large packets of data via cable, but you're really just loading up a teleporter with a knapsack full of external hard drives. At a certain packet size, bicycle couriers are faster than internet for transfer within [many] cities. If this is true for bicycles within a city, it must also be true for your teleporters across the world. They would not be limited by the 100 miles either: you just need a network of stations 100 miles apart where teleporters can hand their bag off to someone else and take a breather while the other guy goes another 100 miles. You would essentially have no competitors for the service provided, and you could protect the secrecy of the operation by claiming to use a proprietary technology that you can't share information about for fear of copycats. This is a better cover than the physical delivery idea because there really isn't any currently conceivable technology that allows for instant transportation of physical goods - you'd have to add an artificial delay to keep people from freaking out, so in the end you're just Feddex with lower overhead. This plausibility also makes you less likely to be the target of GPS snooping. Even if someone does try GPS snooping, this is more easily avoided with hard drives because you're not dealing with sealed containers - you can check out a hard drive, but people will be pissed if you opened up their cardboard box. Source: <https://what-if.xkcd.com/31/> **EDIT:** [Examples of industries that would likely be potential customers for this service](https://en.wikipedia.org/wiki/Sneakernet#Usage_examples). [Answer] # High-Value Secured Shipping Get an initial investment to purchase a few armored cars; make sure the backs of the cars are windowless, and have Faraday cages as well to help thwart tracking. At various points across their "shipping area", buy plots of land in out-of-the-way places and build vaults that amount to bomb shelters; be sure to build Faraday cages into their construction to continue to thwart tracking devices. Post regular guards outside the vaults, but once the vaults are built, the door should be sealed from the inside (welded, and then ~1-2 feet of concrete poured behind it). Now you have secure storage facilities. Adding in Ister's excellent suggestion, the cars would have a small "antechamber" with a normal guard -- just enough room for the guard to sit during the ride; beyond that would be a vault. You could also have bulletproof windows in this section, so the guard can be aware of the surroundings in the event of an attack. As soon as the valuable goods are loaded into the vault and the vault doors are closed, a monk would teleport into the back, and back out to the nearest secure storage facility with the goods; optionally, a second monk would teleport in a dummy package. If the goods are particularly heavy and/or need to traverse exceptional distances, the monks can "bucket brigade" them from secure facility to secure facility (i.e. monk 1 teleports from armored car to facility 1, monk 2 at facility 1 takes it and teleports to facility 2, monk 3 at facility 2 teleports to facility 3, then monk 4 at facility 3 teleports onto the destination armored car. Now the trick here is, the goods get stopped at the final secure facility for an appropriate amount of time, to simulate actual transit of a vehicle. Only when it's reasonable for a series of armored truck transfers to have made it to the destination city do you actually dispatch the delivery truck to the destination. On the receiving end, the driver would be driving an *utterly empty* armored car. As the car pulls up to the destination, once the recipient has been sighted and ID confirmed, a signal is broadcast to the final monk, who teleports into the vault with the goods and back out, just before the vault is opened and the goods are tendered. The vault would be secured electronically, and once the monk is safely out, they'd transmit the unlock signal so the guard in the antechamber could open the vault (so it's not inadvertently opened before/while the monk is popping in and out). With this method: 1. Even if someone attempts to hijack the armored car as it leaves its origin point, since a monk has teleported out with the goods as soon as the car's doors are closed, the hijacker gets nothing because there's nothing in the car. Similarly, if they try to hijack the destination armored car, since the monk and goods aren't in it until the delivery point, they get nothing (in which case you advise the recipient of a delay due to an attack, but assure them that the goods are secure and will be en route shortly) 2. If the shipper puts a tracker on the package, the tracker effectively blinks out of existence as it's loaded on the truck (shielding preventing it from transmitting anything) and since the secure facilities are shielded too, the tracker continues to fail. Once it's offloaded from the destination truck (basically as soon as the doors are opened) a tracker can communicate with the relevant satellites/cell towers/etc, but it looks like the package just "appeared" at its destination at the appropriate time. Offer a 100% door-to-door guarantee, too: "From the moment our truck's doors are closed at the origin to the moment they are opened at the destination, if anything happens to your shipment we will reimburse you ten times the declared value of the shipment." This way if there happens to be an attack at the origin or destination, where the item is actually exposed, it's technically not covered under the guarantee. Beyond that, the shipment isn't anywhere accessible by even the most sophisticated of thieves or crime syndicates (assuming your monks don't get compromised of course) so no one will ever be able to cash in on this guarantee. ### Extra layers of obfuscation and security Have false "secure facilities", with warehouses/garages. Armored trucks go in, armored trucks come out. Anyone trying to follow the truck just sees it go in, then they don't know whether the package of interest has been transferred to another truck, or what's happened. To save money, these could actually be built on top of the actual secure facilities, with the (sealed) entrances contained within, as well as the appropriate ventilation systems to ensure fresh, safe air in the vault. This also allows you to post armed guards around the facility to protect the ventilation systems, while providing a ruse that the guards are just protecting your valuable shipments. Keep dummy packages on the trucks. Put a duplicate label (from the actual deliverable) onto a dummy package, except with a small identifier that it's the dummy, and actually ship the dummy package via your armored car network. Won't would-be attackers be disappointed when they get a box of rocks! The duplicate labels can perhaps have a component printed in UV sensitive ink, so black lights in the trucks and secure facilities can help differentiate the actual packages and prevent mishaps where a dummy package ends up getting delivered instead of the real deal. Well, both labels would have a UV label, but you'd have a convention where maybe the dummy packages have a number printed in UV that ends in an odd digit, while the real packages have the same number but ending in an even digit. Have a full armed security escort on the trucks and at the dummy facilities at all times; make it *look* like you're using this to protect the packages; plus, if someone *does* attack a truck (or facility) you can put up an honest show of defending it (even if you're not actually defending the secured goods). The security folks can be mundane people -- any private security firm or internal hires of "normal" people. They'll never be inside the backs of the trucks or the actual (or dummy) secured facilities, so they'll never see what's going on. In the unfortunate event of an attack, you're not risking the loss of a valuable monk (reducing the organization's teleport capabilities), but just the usual risks associated with armed/armored transport (you have insurance for your guards right?) For maximum security, since ventilation is the only potential avenue of risk here, have massive pressurized air tanks buried adjacent to the vault (and sealed in concrete); if the air intake systems detect any contaminants (biological or chemical agents) they seal off the outside airflow and can keep a nominal supply of fresh air flowing into the vault for hours or even days via the tanks, and scrubbers can help recycle air within the vault (removing excess CO2) for even longer operational periods without outside air. Once the air is determined to be clean again, compressors can refill the storage tanks as needed. Periodically cycling air in the tanks is probably a good idea too, because stale air sucks :P Cheers to Ister who suggested the inner vault and guard in the truck, to cover things up in the event of an attack (i.e. "we saw someone go in the back of the truck but now it's empty!" -- having a guard in there and not having the monk do the teleport until the vault is sealed avoids that). [Answer] **Generate Energy** *Assuming your teleporters "break" the laws of physics and can teleport items to higher energy states for free* **Money making** You could use your teleporters to move mass to a high point and let it fall, collecting the released potential energy. Think a hydroelectric dam, but you can use your teleporters to infinitely re-use the same water. Using the teleporters, you could indefinitely turn huge turbines, creating huge amounts of electricity much easier than your competitors. **Secrecy** You could operate under the guise of generating energy a large number of ways. The ones that come to mind to me as being the most concealed are geothermal and nuclear. You could generate your electricity in a remote location to avoid suspicion. **Lacking power...** Actually, considering the weight limitation of your teleporters, this probably wouldn't generate enough power. Quick calculations give only about a sustained rate of 27kW per teleporter of maximum output. Given about 3 dollars per kilowatt-day, that's a solid 81 dollars a day per teleporer. To use this method, the teleporter would probably have to be stronger. With the given specs, and 90% efficient turbines, you could get about $25,000 a year per teleporter. The math I used : $5 \text{kg} \times 160000 \text{m} \times 9.8\text {m/s}^2 \times 300\text{/day} \times\frac{1}{86400}\text {day/s} = \approx 27\text{kW}$ For clarity: $5\text{kg} \approx 10\text{lbs}, 160000 \text{m} \approx 100 \text{miles}$ [Answer] This may only work for a few of your people, but . . . Have you considered a ## Magic act? Sometimes, the best secrets are hidden in plane sight. Create magic acts based upon people "appearing" to be teleporting. Other magicians will be amazed at your prowess with sleight of hand! You have video evidence that you were in New York seconds before appearing in Vegas! Then moments later you were in Hong Kong! Then the space station! Are you quadruplets?!? It's amazing!!! If people catch on, you can even claim that you were raised by a cult living in the mountains where everyone can teleport. For good measure, your mountain village (possibly a fake, but resembling the real thing) with no roads leading in or out can be part of your act. You can even make it a high end tourist attraction if you gain enough of a following! The proceeds may not be enough for your whole commune to live on, but it would probably be enough for a nice start. --- **Edit**: Worth noting, teleporting doesn't just work on the huge "New York to Vegas" scale: it can also work on the "stage left to stage right" scale. Although I'm guessing that there'll be a popping sound any time someone teleports. We may need to figure out some way to play that into the act . . . add a puff of smoke or something. [Answer] The biggest hindrance to the plan is their lack of knowledge about the world. If they couldn't handle a job interview, starting and running a business would be a real problem. They'd likely need to employ some form of intermediary. I imagine it's not nearly as big a thing as they make it look in fiction, but imagine an Amish community wanting to start a major, I dunno, furniture making business. They can make the chairs and tables easy enough, but certain facets of the distribution and business arena are either out of their experience, or perhaps things they're not allowed to do. So they hire a middleman to handle the business end - pick up the merchandise, take the orders online, etc. As long as the person in question is ethical, and doesn't take advantage of the community, everybody makes money. So the Porters make a deal with someone who serves as their intermediary. They need not know their secret, just that they use proprietary procedures that they will not share. Again, as long as the businessperson in question does not get inquisitive, or try to abuse the community, things could go well. Taking that into account, many of the idea suggested here could work well. The important part is that front-facing person who serves as the spokesman. [Answer] The main issue is maintaining secrecy. Therefore, whatever they do, they need to acquire enough knowledge of the external world to safely pass routine communication and inspections in their chosen area. The obvious job would be the courier service regarding which I only have a couple notes in addition or what others have written: 1) I disagree that they should go into bulk transportation - it would still probably pay more to deliver confidential documents or expensive items rather than go for bulk items. 2) Their main benefit is not *speed* because they can't deliver faster than it is physically possible using fastest normal means *without endangering their secrecy*. Their main selling point is **security during transportation**. Apart from the courier service one of the more interesting things they could do would be **precision teleportation**, which doesn't care that much for distance, as much as for the ability to place the right thing inside another solid thing at the right place. For example, think correct placement of remote explosives in mining operation, or similar. If they gain enough knowledge of geology and mining operations, they could literally save millions of dollars by teleporting stuff inside mountain without drilling hundreds of meters of rock. For majority of operations though, they would have to educate themselves to a quite high level. [Answer] One teleportation in and out of Ft Knox, and you're set for life. Oh, you said ethically responsible... and only people... They could teleport nasty dictators or terrorists into jail before they start killing people. A lot cheaper than having to take military action against them, and you'd be saving lives by stopping the hostile action before it started. Needless to say, the major governments would want to keep this capability secret, so no problem with remaining under the radar. InstantJustice.com... for one billion dollars, we'll teleport that dictator into the holding cell of your choice. You'll spend ten billion if you have to send the military in, and with our service, there will be no casualties or destruction. Oh, and if you don't pay your bill, you'll be teleported into a holding cell of our choice. [Answer] Steal drugs (life saving ones) and sell them at a fraction of the normal price in poor countries. They are relatively lightweight and you only need teleportation for stealing them, not for the whole transport. The general idea is to find some crime you are ok with. That's much easier than legal ventures. [Answer] ### Personal transportation Look for jobs that require personal transportation. For example, sales jobs often require personal meetings in multiple locations. Significant portions of their time is spent in travel from one place to another. But teleporters can skip most of the travel. They can therefore do more sales calls than people who have to do the travel themselves, but their pay rate will be based on a rate sufficient to support that travel. They will have to do some work to avoid being caught out. They can purchase property near the locations and store cars there. So they only drive the first and last few miles rather than the whole distance. Get two or more jobs so that they won't seem to be nearly as advanced. They can interleave the jobs, doing sales calls for one while supposedly doing transport for another. Eventually they make enough capital to buy their own business and can then take less care. Only they know how many sales calls they are actually doing. They also don't need to carry anything with them. They can leave the stuff they need at the remote locations. That includes a car, briefcase, etc. Ship the actual product normally. ### Bicycle delivery It might be difficult to get the capital for buying extra locations with the sales job. So start with something smaller. Get jobs making deliveries on bicycles. Turn into empty alleys (or go to your apartment) and teleport closer. Don't hurry too much, so they don't get caught. But a teleporter can take all the far deliveries and do a better job. They can be even less careful once there are funds enough to buy their own business. They can even mix teleporters with regular personnel so that people just assume that they see all the people moving. Arrange things so that the teleport deliveries are in a separate room so that they can just pop in and out. Bicycle delivery doesn't pay much, but it would pay more if people could skip the intermediate part. And it can help ramp things up if initial funds are limited. ### Unskilled One of the advantages of transportation jobs is that they are mostly unskilled. There is a little bit of training but mostly the job is to move between places. It won't pay much, but by skipping the time involved, it can pay more. The sales job is similar. Sales is harder, but it still is not rocket science (unless of course you are selling rocket parts). Send out regular sales people to make the initial contact and use the teleporters to maintain things. They can just give the standard sales spiel and mark down what needs to be delivered. [Answer] **Secret agents.** The protagonist in Jumper has teleporting abilities. <https://en.wikipedia.org/wiki/Jumper_(novel)> He catches a terrorist and ultimately turns him in after much pathos and bathos. Your folks could cut to the chase. Catch the wanted and turn them in for the reward. They could be bounty hunters. <https://rewardsforjustice.net/english/most-wanted/all-regions.html> The CIA would get curious how this was being done and would take measures to find out, so there would need to be a middleman who could not rat them out when he got waterboarded. But maybe the teleporters can do better by working with the CIA. Once the CIA handlers knew about the teleporting powers of these folks they could put them to good use by giving coordinates, targets, materials and so on. The teleporters could whisk away persons of interest, rescue hostages, plant evidence in the apartments of people, retrieve intelligence from secure areas and so on. They could even be saboteurs - for example dropping off explosives in uranium enrichment facilities. Their secret would be safe - the CIA is good at keeping secrets and would be strongly motivated to do so - once other states and persons of interest learn what is possible they will take protective measures. [Answer] ## Rescue I would create a rescue company. Advertise worldwide that you can rescue anyone, or anything, from anywhere. A few example: * My big oil tanker is sinking: take all the teleporters together, bring it close to the shore quickly. * My friend got kidnapped by some crazy fanatics in hostile country: a teleporter will go to his cell, blindfold him, and jump again to the next embassy. * Someone is stuck in the mountain before a storm: saved by a teleporter * My son got wrongly convicted of drug trafficking somewhere in Asia: go to the jail, escape with him. Of course, you need to make sure of a few things: * The people rescued are always blindfolded before the teleportation occurs, so they don’t understand how it happened. * The price is very high for rescues, so you make a few big ones rather than many little ones: less chances of being caught. --- ### Edit to clarify how rescued people are kept ignorant about teleporters A lot of comments focused about this, however, I believe there is a lot of ways to make sure they never understand how they were rescued: * As suggested by Llewellyn, an untrained person will pass out when teleported * Or teleport is completely feelingless. So they blindfold the person, they teleport him to a kind of movie studio of they own, and simulate for him (still blindfolded) an escape by helicopter, with all the sound and movement they wish. [Answer] I'm afraid that you can't. What's the very first thing you have to do to avoid scams and frauds (in the internet or in real life)? Look for a well-known, reputable business. Every legal enterprise you want to start up would need beforehand a registered headquarters, with a proper fiscal identification, owners and the like. If yours it's a secret organization, no one is going to trust you for any kind of legal activity - which left you with illegal ones. Now, finding illegal but ethical activities depends totally on what you think is ethical. If you are in favor of legalization of drugs, drug trafficking may be the best solution. Some members of your organization can go to a drug cartel and make an offer for a secure, untraceable freight delivery service. I'm sorry, but it must be done with a cartel. If you want to bypass the cartel and deal directly with the poor coca or poppy farmers in Colombia or Afghanistan you'd have to talk to too many people, forsaking any secrecy, and then you'd be responsible for their unavoidable deaths at the hands of the furious cartel's hitmen - if you managed to convince them to work for you at all to start with. [Answer] I'm not sure what the name is for this kind of business, but once it has built an initial reputation, it would be able to charge a fortune, and no questions asked (or none that cannot routinely be answered/deflected). There is a kind of business which some heavy duty security companies run (think [Kroll](https://en.m.wikipedia.org/wiki/Kroll_Inc.), or other security-for-hire which work on a project or retainer basis). So you have a tanker, freight ship or aircraft that's hijacked, or you suspect industrial espionage or stealing of your intellectual property. The company can claim to be using arcane knowledge, skills and disciplines passed down for generations. They can teleport into any vessel or aircraft, or into any competitor's offices and security zones - the only requirement in the OP is ethics, which comes down to accepting some contracts and declining others. Since the business is in security and investigation, its operational arm would not be expected to explain how it achieves its results. [Answer] **Worlds Most Secure Bank** Getting the start up funds might be hard, but all vault or safety deposit box access could be handled behind closed doors. Since the vault would only need small air vents and not a person sized entrance way, it would be perfectly secure from outsiders. The actual teleportation distance would be only a matter of feet and most loads would be light so the amount of stress on the teleporters would be small. Any GPS device hidden inside a safety deposit box would be moving a distance that, with the interference from the vault, could be seen as margin of error. Your only concern for discovery is someone breaking into the place and not finding any door, which would not be entirely conclusive. Actual employee requirement would be small and profits could be huge. This option could leave the monks with nice benefits like vacation days, regular working hours, and no need to be on call. [Answer] **Liposuction!** Set yourself up as alternative health practitioners and give people 'ancient monk massages' which the hype says will enable them to sweat their fat away. In reality you are teleporting the fat into a bucket next door. The pummelling of the massage will cover the pain of the fat being ripped out of their body. Given what people will pay for dieting and health fads which don't actually work, you'll be raking it in if yours does. You can also sell them prayer wheels or rosary beads or whatever religious paraphenalia your monks use at the same time (at hugely marked up prices). Of course, you'll have to set up somewhere where what they are doing isn't seen as a medical thing, so that you won't have to be inspected or have medical researchers wanting to test your methods. [Answer] While it may take the deft maneuvering only a seasoned monk could handle, one thing I haven't seen mentioned is Latency Arbitrage: <http://altanswer.com/video/latency-arbitrage/> Do some small tasks to get a few monks, dressed and looking the same on a trading room floor of a large exchange. These monks are able to see the big moves of large institutions on the floor, they then teleport to their home office to make a penny or two on the dollar per trade. A couple monks doing this could start to produce the required income in a pretty short amount of time. Stayin undetected would be hard but not impossible, given the chaotic nature of the place. No one gets hurt, and MUCH more many flows through places like that in a given day, let alone a year. [Answer] **Skimp on Shipping Insurance** Lots of importers/exporters have to worry about insurance cost because of theft, fire, mechanical failure, atmospheric conditions. Depending on what you ship to whom. For your monks these cost are non existent. The trick is deceiving people in that you are shipping the stuff. You just happen to have that specif item always on hand in there closest warehouse. Lets give some examples * **Anti-venom/toxins**: Lots of expense easily spoil-able medicine (and rare blood types) out there that hospital just don't stock-up and order only when a person enter's bitten by that specific creature. Have a small warehouse in each major city and advertise you have a stock of every type of anti-venom in every one of them. You only have one central warehouse staffed by monks. * **Fresh Seafood** Build small aquariums in big cities and again advertise you have a large supply of Seafood shipped overnight still fresh still alive in some cases. Restaurants and other catering services will pay you more money for that service than they will charge their customers, The prestige of having still living wild tuna freshly caught from the other side of the globe is worth allot. also as a bonus lots of restaurants would see there food waste decrease if they don't have to pre-order a day in advance. * **LEO** Already suggested by others but send a empty rocket into space then if the launch is successful. Which is not a guarantee, (which is why insurance is expensive on launches). They teleport the food, water and/or spare parts up there. Unfortunately you wont be able to transport specialty parts because you wont be able to explain them surviving a crash. Just offer it as a cheap service using old rockets engine with high change of failure. These regular supply runs can be very profitable if you only send up air and fill it up once in orbit. While commercial space flight is in its infancy. A estimate for cost charged per kilo to the ISS can vary between 20.000 and 100.000 dollars. * **Diplomatic mail**. Lots and lots of things gets shipped through diplomatic pouches every day. They are handled by commercial shipping companies like any other but they over a tantalizing benefit nobody is allowed to open them. Again you can overbook private charter flights. Advertise you offer secrecy above all. Nobody will know what route it took to reach its destination. If a plane is lots by accident just claim its contents where private. The first res ponders already removed the cargo before other people showed up or just say it was flying empty which was the truth. [Answer] ## Absolutely, positively overnight You run an express delivery service in a way entirely achievable with normal means, but hard to do perfectly. **You do it perfectly.** Because when something goes awry, you use your teleport gang to fix it. Take McMaster-Carr. They have warehouses strategically placed so they can reach most Americans overnight with cheap UPS ground service. Warehouses carry most things BLIP! *all* things. A TelEx cargo Airbus 340 climbs out of Heathrow when BLAM! A wayward drone is ingested by the #3 engine, throwing shrapnel into #4 . With all the thrust on the left side, the heavily laden craft's rudder can't BLIP! *empty craft's rudder can easily* turn the plane back to an uneventful landing. Your company just doesn't have the kind of misfortune everyone else in the business does. ]

[Question] [ Just last week while developing a new CCTV camera system I accidentally produced a free energy generator. I know, what are the odds? So now I'd like to make some money. Unfortunately, this device is so simple and effective that I cannot release the plans - the destructive potential is too great. I seriously doubt my ability to protect the design if spied upon or interrogated, so I need to monetize this without anyone knowing what I'm doing. The device itself is trivial to build. It directly adds thermal energy to matter in a target region near the device. The first version cost me £1 in materials, weighed 500g with a volume of 1l and heated a 10cm³ spherical region 1m away from itself. I was unable to find an upper limit to the power it could produce before the device and my entire kitchen burst into flames (you see why I need money?) but I believe it can continually sustain at least 1MW. I can scale the device up or down with all the above variables changing linearly (a 2l device would cost £2, weigh 1kg and provide up to 2MW to a 20cm³ sphere 2m away). Power production can be turned up/down extremely fast. Assume I am a 25 year old engineer in the UK with no special connections, £10k in savings and access to £20k in credit if necessary. I am willing to spend years on this plan if the return is sufficiently large (e.g. if it takes a decade to have a cheap gigawatt power plant pouring its profits into my bank account that is fine). **How do I monetize this device without revealing my invention or raising enough suspicion to prompt an investigation?** [Answer] You could use your invention to power computer hardware to "mine" a cryptocurrency like bitcoin. "Proof of work" cryptocurrencies like bitcoin [deliberately waste enormous amounts of energy](https://motherboard.vice.com/en_us/article/aek3za/bitcoin-could-consume-as-much-electricity-as-denmark-by-2020) generating redundant [cryptographic hashes](https://en.wikipedia.org/wiki/Cryptographic_hash_function). Today, most cryptocurrency mining happens in places with cheap electricity, because the limiting economic factor is the cost of the electricity wasted relative to the value of the cryptographic tokens generated. If you had a limitless source of free electricity, you could use it to power your bitcoin-mining rig, generating the tokens for free (minus initial setup costs), and then you could sell the resulting bitcoins (or other cryptocurrency tokens) on [relatively] anonymous online exchanges. [Answer] # Seed money So you've got a device which can increase the temperature of water in an arbitrary location far from the actual device. A 10 million pound version of this device is basically a weapon of mass destruction that can wipe out any city on the globe. I can see why you want to be careful with it. **Fake fusion** Set up a fake "fusion" power scam company. With a twist, you let anyone as in literally anyone come in and examine your "fusion reactor", you even allow them to take it apart. But what you'll allow them to take apart is not your real power source. it's a dummy. You built a £1000 model and placed it somewhere within the building less than 1000 meters away. You're an engineer, dig up some examples of old fusion scams but add your own personal flair. Make it complex. Make up some vaguely plausible technobabble and some parts that do nothing except add complexity and make it hard to conclusively say it's not a fusion reactor. But you do something that almost no fusion scam artists ever do: you invite in any independent engineer willing to come and look, you allow them to take your "reactor" to pieces to verify that it has no batteries or any other known tricks. You even invite in some professional magicians. then you put it back together with them and turn it on and it blasts out lots of hot water for hours without any connections which could hide the trick. **People will still call it a scam** But you'll probably be able to get enough funding to build an industrial size model. What you actually do is spend another £1000 on one of your secret boxes and some of the investments on a big "reactor" and then you set it running. **It's hard to argue with "success"** You even patent you "fusion reactor" with detailed parts lists. At this point, you're turning heads because you have a small real power station putting out real power but nobody can get copies of your "reactor" to work. You keep waffling about how they need to get the "quantum alignment of the modulators" completely correct. You start getting billion dollar contracts to build full-size stations for countries. What you actually do is hide one of your real reactors and aim it at the focus point of your fake "fusion reactors". Still, nobody can work out how they work or replicate them but nobody knows to look in the foundation of one of your admin buildings 10KM away. Spies keep focusing on your fake reactors. Even when they steal one from a running plant they still can never get it to work outside of your own plant (except for a couple of times when you wanted to mess with them and powered it up remotely from one of your real reactors to make them think they'd finally figured it out or were getting close). Congratulations, you're now a multi-billionaire who could seize control of the entire world if he felt like it. [Answer] Consider looking into what and where power is needed, on demand, and people are willing to pay for it. Take for example [Electric Car charging points](https://chargemasterplc.com/products#product-3). If you can install one of these with a payment mechanism, people will assume it's using Grid energy when in reality it's generated from your invention. The difficulty will come during the accounting phase, but I think this is true however you plan to make secret money! [Answer] ## Refine aluminium A great many commodities require a lot of energy to produce, to the extent that it determines their value. For example, aluminium is extracted from bauxite via electrolysis and requires so much energy that it can be used [as a virtual battery to even out demand](https://www.greentechmedia.com/articles/read/german-firm-turns-aluminum-smelter-into-huge-battery). This could be a pretty good cover for both connecting to the grid and making money from pricing disparities in the energy market, and also selling a product of your excessive energy. Just build a power plant next door to cover the apparent abundance of energy. [Aluminium-Air battery](https://en.wikipedia.org/wiki/Aluminium%E2%80%93air_battery) technology might be another avenue; as it is a single-use technology, selling new Al-Air battery packs and recycling old ones would be a good cover, and if you can get everyone's cars hooked on cheap, light batteries there would be political reasons to protect you. ## Or produce fresh water Alternatively, desalination (extracting drinking water from sea water) is a huge barrier to irrigation in many countries which actually have a sea-coast. So you could conceivably set up shop in such a nation with some hand-waving argument about a super-efficient desalination process, and you'll find that apart from someone trying to extract the information from you, the population should protect you to keep their cheap irrigation going. ## Unless you have a flair for the nefarious Another longer-term option would be to secretly build up a store of something, and then when governments come knocking you can threaten to destabilise things unless they give you money/IP rights/their firstborn. This is a bit more Austin Powers - you build a secret store under the sea which is powered by this energy source, and build up a vast pile of aluminium/gold/etc. ## Or join forces with one A better, and simpler, option would be to engage another maverick with the capacity to make use of your thing, like Elon Musk. A magical power source would be just what he needs for electric cars and space rockets, albeit his solar stuff would suffer, and he could deal with the intellectual property needs. An alternative might be to engage global companies like Google for whom the source would immediately save them vast sums, although the temptation would be to silence you as soon as they understand it. ## But it would change the world, and endanger you with it As soon as the magical power source is public, though, most of the bets are off - it is such an explosively powerful capability that unless the scientific detail is made freely available it would trigger a series of conflicts on the basis of differential access to it. So unless you want to be responsible for global wars just because you want a slice of the pie, it would be better to just publish the patent and hire a decent PR agent, perhaps after discussing the thing with your country's defence ministry/agency. Unfortunately you are no longer safe from anyone, from political to business players, and the status quo is rather valuable to them. ## One day, it will happen Back in reality, when it comes, if it scales, fusion power will be utterly transformative for the human race. The deserts will bloom, the hungry will be fed, the world order will be overturned, the rich will escape to orbital habitats, or to Mars. [Answer] Many of the suggestions here include the idea of creating a power plant and laundering your electricity, but there is a safer way. **Geothermal power.** So you dig a big hole in your back yard, pump down cold water and hot water comes out. Normally the water temperature would increase by 1 - 4 degrees, but you can of course add some extra heating to the tube and get far larger gains. If you don't deploy sensors there is no way to accurately check how hot it actually is down there, and thus it is impossible to detect this "fraud". [Answer] Since according the known laws of physics one cannot create energy from nowhere, your device, spitting out energy without any input would immediatly raise suspects. Your only way for secrecy is therefore to fly low and to disguise it: sell it or show it as "highly optimized engine": you basically couple it to a conventional power source, and you use your invention to cover the gap between your source and the Carnot yield for the same source. (i.e. let's say it is a power generator with a Carnot yield of 40%, but it has an actual yield of 25%. You use your device to generate the missing part). If you are also able to implement some sort of "destruction upon opening" you can further protect your invention from curious eyes. [Answer] Let me suggest that monetizing this energy producer is the wrong path. You're thinking too short-term. When economic drivers are reduced to their fundamental parts, energy is one-third of the equation (time and transportation being the other parts). If energy suddenly became free, there's strong reason to believe that humanity can finally enter that egalitarian utopia we've dreamed about since the first human didn't want to get up and scrounge for food in the morning. Free energy would represent a turning point in human development. It would mark the final nail of hindrance on human capacity (time can be made up by adding humans, and transportation is only affected by time now, because the energy to transport is free). Release the plans to the public.1 In only a year or two, you'll find that money is far less of a problem for you than it ever was. After you do that, people far more clever than you will learn how to control it, then offer cheap home generators on amazon and ebay. There may be a sudden rise in unemployment, making jobs difficult to acquire, but suddenly the cost of almost everything will drop significantly, and some things will become free.2 Scientific advancement will start taking leaps in the following decades, instead of baby steps, because things like the LHC or launching a shuttle are now energy free (grants to operate them will no longer need to be so massive. Production of any good could be exponentially increased as needed, and eventually, actual energy-to-matter conversion will be discovered, developed, and mobilized for society's needs. You've unintentionally solved almost all human problems. Or, you've at least made it possible. Utopia is no longer a dream; it is an attainable reality. --- 1. Naturally, there's super-villains in every story that would rather subjugate than advance humanity (you don't sound like a super-villain, hence my alternative answer). These people would try their hardest to keep your discovery to themselves and exploit is for personal gain. That's why you would need to release the plans to the public. If everyone knows about it and it's simple enough to build at home, there may be an initial rise in burnt home kitchens, but the ultimate effect will be the removal of energy costs from the economic equation. 2. Utilities are the obvious first changers. After that will follow anything that depends heavily on energy consumption to produce. This includes freight-expensive, but cheap production, goods. Fuel will no longer be needed. All transportation will become electric, because electricity will be free, or nearly free. Food fits in here. So does any computing. [Answer] **Build a power plant.** Not a power plant that utilizes your invention, but something like a wind/hydro station. Build the station, have all the real equipment in there, but at its heart hide your devices (in a broom closet or something no one would suspect, or even in your private office under the floor). So yeah, one that utilizes your invention... but doesn't. Maybe even claim special turbine designs that are supposedly more efficient/cost-effective so that you aren't questioned on how you're outputting so much more energy/make so much more money. These designs are your trade secret and since no one in their right mind would consider a CCTV technology leading to free-energy, I doubt anyone will replicate your technology and therefore you don't need a patent or anything. ***EDIT: claiming special turbine designs will also lead anyone trying to replicate your technology down the wrong path, making it even more unlikely that anyone will duplicate your tech. Also, since it's not some new revolutionary technology like fusion, you will have fewer skeptics and fewer scientists trying to debunk/vet your designs.*** This way, you'll pass industrial safety inspections because you actually have all the turbines and stuff, pass most scrutiny against your turbines since the designs a secret, and you'll secretly be supplying energy from your free energy device(s). What I'm suggesting is essentially energy-laundering, like mafia's do with money but, you know, with energy. **Make it look like legitimate energy production, but in truth it is not.** This has the benefit of you being able to create a huge company to make billions of dollars across the nation (I'm assuming the USA, even though you're a Britt, because it has the most corp-centric laws/attitudes in the world [in my opiion] and is one of the largest [or the largest] power consuming nation in the world). [Answer] Buy a petrol station, and set up a process to [pull carbon dioxide from the air and convert it to gasoline](https://news.usc.edu/91297/turning-air-into-fuel-usc-scientists-turn-carbon-dioxide-into-methanol/). You will still have to buy some petrol from a distributor, to avoid raising suspicion. Once your first petrol station is profitable, buy a few. Once you own about a thousand, buy a gasoline distributor. Work your way up until you own an oil company. Then you can buy operational oil wells and shut them down. [Answer] Put the results on [arxiv](https://arxiv.org/), send a paper to Science. Then wait one year to collect the Nobel prize. As discussed in the above answers, you'd have given the world free energy and everything would change. With your prize money, you can retire in a nice third world country like mine and live happily ever after. [Answer] **Colonise Mars** Use one of the methods described elsewhere on this page to get enough money to construct a robust [closed ecological system](https://en.wikipedia.org/wiki/Closed_ecological_system) on Earth. When you feel you are close to being discovered, you blast off! Your generator can be used as a rocket engine; either heat up some propellent for a fast trip, or position the heated point on the other side of a mirror for a reaction less drive. When you get to Mars, unplug the generator from your engines, and use it to power greenhouses. Take along some friends, and congratulations. You're humanity's best hope for survival. I know you said monetise, and strictly speaking this doesn't produce cash you can spend, but hey - you're the monarch of a whole planet. That's got to count for something. [Answer] I am surprised nobody mentioned the following yet: **Manipulate Stock Markets** Using his device, the protagonist can easily create unexpected (and prevent anticipated) natural disasters, create energy blackouts, turn the tide of military conflicts, create fake terrorist attacks where by "pure luck" (i.e., your careful planning) nobody gets hurt, etc.. On every such event, the protagonist buys put/call options on a stock. Since such events have dramatic impacts on the stock market, an option can sell for a multiple of its price. The activity can be well hidden by also buying options which do not monetize. Once the protagonist earned enough money, many of the other answers to this question (for example the fake fusion plant) become feasible. [Answer] Producing or selling any kind of engine, generator or power plant will very shortly lead to the discovery of your invention, no matter how well you're trying to cover it up. At the lower levels, hobbyists and tinkerers get in your way, and at the higher levels safety inspectors get you. So you'll need to add indirections. **Sell the product, not the energy.** I got so many ideas, but most of them fail if you can't even afford to renovate your kitchen. For starters you need something you can operate from a basement, something regulators don't understand, and something which benefits a lot from cheap energy. I hate to suggest this, because it gets mentioned so often when it doesn't really fit, but it seems like you'll become a bitcoin miner. [Answer] If you stumbled across it, and it's so simple that it will automatically spread, then you have to assume that others will discover it as well. This is made that much uglier by the fact that no secrecy is perfect. *any* means of making money off this has a decent chance of eventually revealing it to the world, particularly if you're involving other people. Plans that require a large number of years are, as such, likely to be untenable - the chance is too high that someone else will publish the thing in the meantime, your competitive advantage will vanish, and you'll be left even further in debt than you were. So the question changes a bit - how do you make money off of this thing while you have it, and how do you limit the devastation in the world once it gets out? For the first, you in part should try to be making money off of knowing that things are about to change. Short-selling aluminum futures, for example. For the second, it's a matter of figuring out what the real risks are, and then figuring out who to warn so that they can prep for the release of the information (and then who to release it to). Also, when you do release it, do so in a way that makes you a chunk of change up front, gets you entirely out of the power-generation business (except perhaps as a technical consultant) and makes sure that people know that you were the one that made it all happen. There are a lot of people who will fight bitterly over control of easily accessible power. You don't want any part of that battle. On the other hand, working the celebrity factor can be pretty lucrative too (if exhausting) and doesn't carry anything like the same level of risk (though it does make your personal life massively overexposed). [Answer] The best way to make money is to sell it to someone like an oil company. They will happily hand you a pile of cash not to tell anyone about it. Just make sure you have a deadman failsafe that will release the designs on the internet should you "slip" in the bathroom and break your neck. [Answer] # Become the worlds most unstoppable and deadly assassin This is an option if you're willing to go to the dark side. Spend 10K on a 10GW version. You can now zap any location within 10km. Zapping full force for 1 second at 10 GWatts/h is roughly equivalent to setting off a few pounds of TNT at that location. Move to a major city, put lots of effort into creating ridiculously hard to trace ways to receive payments and go into business offering assassination as a service. You never get closer than 5KM's from the target, you can even be publicly visible on a mall security camera miles away when the targets hotel room explodes. eventually you may start to attract law enforcement attention... but your machine on low power can also burn a warning message into the wall of a state governers home. You can become a shadow-gangster running an organization from the shadows capable of taking out any rival. Once you have some cash from smaller hits build a 100K or million dollar version and just move across the country to somewhere out of the way where no suspicion can fall on you. Go for higher end targets from further away with more power. You can take out a head of state from a thousand KM away now. eventually build yourself a 10 million dollar version. Now you can kill anyone anywhere on earth. You can blow apart any military bunker, you can burn any city to bedrock, kill any head of state who defies you or kill anyone who gets within 100KM of your supervillian lair (which is of course about 500 km from your real residence which is a nice beach house) An interesting side note: 1000 dollar versions set to quickly turn on and off at lowest power could also be used to transmit data from one location to another 1km away without any possibility of tracing the connection and can also burn the other node and anything nearby at a moments notice should it face being compromised. Become the worlds secret leader with the threat of death hanging over the heads of anyone who defies you. [Answer] It seems there is but one obvious answer: Build giant lasers and point them at major cities. Use a subtle strategy to launder the energy and use the capital to build energy weapons. Once the threat is believed (might take some aggressive convincing) and the blackmail money starts coming in, I doubt anyone would question the source of the energy when the loudspeaker blares "one step closer mr inspector and downtown Manhattan gets vaporised". [Answer] **Grow marijuana.** You don't have the capital for a power plant. Basement growers get caught because their energy bills go up, but you don't have that problem. Absent-mindedly add sparky-shoddy-looking "line filters" on the power lines, "to keep the cops from noticing". The correct idea is Magicsowon's "publish and retire", but your guy could be entertainingly naive in some ways. Until he hires/befriends the genial, "retired" Professor Pothead... [Answer] **Sell the power to a power company.** This kind of thing happens all the time. One company will promise its consumers that a certain percentage of their power going forward will come from solar or wind, or perhaps they end up with more customers than they can support on their own without building/buying a new facility. So what they will do in order to meet their commitments is actually buy power from another company to resell to its consumers, either as a permanent solution or in the meantime while they acquire new facilities. So, solution is simple. Build 100MW worth of devices, get a business license, sell it for less than your customers (the power company) charges their consumers, rake in dough. The US national average is about 11 cents per KWh, which at 100MW and a 50% margin for the power company, nets you about $8k/hr at full capacity. If you give them a high enough margin, you'll get more and more business from more and more companies. Then just build a massive vault so you can swim in all your gold coins. You might have to get a bit creative on how you pitch the power to the company without revealing where it comes from... but you can think of something. [Answer] (explanation:) This is the worldbuilding stackexchange, so, even though you mention the UK, we must not be just talking about a pretext for a novel. We must be talking about building an alternate future for this world. And what would a free energy source be good for other than making a Utopia? (end explanation) This world is not the kind of world that deals well with Utopias, so don't get grand plans that direction, if it's this world you are talking about. (explanation:) But, then again, it could be an alternate time-line or a look-alike world. (end explanation) If it's another world (in the story you're writing), you control all the variables. Take the course that is interesting to you, and remember, worlds do not exist to be made into Utopias. (explanation) It should go without saying I think, that you can decide what kind of access your inventor character has to banks, businesses, trusted partners, not-so-trustworthy partners, etc. Or maybe it's not just the energy source, but the actual ability to perform alchemy. You control the laws of physics. But there are a few things you can't control in building worlds. (end explanation) Intelligence is there to be used. That means that worlds are there for giving intelligent beings problems to solve. So even if you are writing a novel, it comes back to one thing: Do you want the invention to cause destruction or to help people? (explanation:) It cannot be automatically assumed that destruction is contrary to the assumed goal of worldbuilding. Bad guys, by their arrogance and other failings, often take themselves out of the social equation by blowing themselves up or attacking the wrong people, etc., and, by their disappearance, leave a world that is "better" or more ideal or something. (end explanation) If you want it to cause destruction, use it to try to help other people magically. If you want to use it to help other people, use it to help yourself, first. Hide it from the fire inspector, get a real job, save up money, use it to heat the apartment in winter and pump the coolant in the summer. As you figure out ways to use it for your own needs, you can figure out ways it can help others. When you meet others who have discovered it and are doing the same, you help each other. Eventually, enough people know how it works and are using it that the empire builders will be unable to do anything really bad with it any more. (explanation:) For all sorts of reasons, sudden social change is generally disruptive. Even in fiction, it's easier to keep social change under control when the changes are introduced gradually, and the gradual introduction is the best way to keep your free energy thingy secret. I'm not saying the slow approach is always best, just that it's the easiest to keep control of and the easiest to keep secret. (end explanation) [Answer] ### Create efficiencies for industry Find some existing businesses which would profit from your idea, and share it with a small number of members of each business. This will allow them to reduce costs by a huge amount, and they could pass some of the savings onto you. If you share your ideas with only a moderate number of competitors in each industry, you could keep some competition in the marketplace, so the savings were passed on to customers. Co-operate with members of those companies to devise ways to hide the free energy, such as through fake proprietary methods for doing X more efficiently. Every company would have an incentive to hide the fact of the new technology, since doing so would prevent a significant further increase in competition. They would also have an incentive to ensure that only a small number of people ever learned the workings of the new technology. They might try to introduce the technology to new areas, but you would be alert to any other industries where one or a few businesses had a sudden price drop. You could muscle in with your technology to claim your share and to dramatically reduce that other company's margins, but in the end, society would still get cheaper products with the same incentive towards secrecy about your device. [Answer] Deceive, inveigle, obfuscate. Hide in the complexity of other things. ## Run a crypto exchange. Become *reverse FTX*. Your business has a cover. And the cover is you exchange cryptocurrencies, sort of like the infamous FTX. Except instead of actually running a deficit and using Ponzi like devices to prop yourself up, you run a surplus and use the complexity of the business to hide it. I.E. Laundering electricity. One aspect of your business is mining crypto on your own computers. Where do you get the electricity to do this? **Financial regulators don't CARE.** This is the crux of your "scam": no one ever asks where your electricity comes from. But you do a lot more: * John Bogle 101: The *real* money in investing is made on charging the customer expenses and fees. So the sly old broker trick is to sell extremely complex **derivatives**; very complex financial products that nobody can really understand, so it's impossible to compare them to market indexes to see if they're a good investment. Traditionally brokers use it to conceal fees. So you sell a lot of them: **no one is surprised** when a derivatives trader makes a ton of money. * Unlike FTX, you handle customer investments absolutely prudently and correctly, so no-one ever has a basis to complain, and investigations are quickly closed. Where a real tragedy happens, you reach into your own profits and cover some losses. Regulators start viewing you as a "a rare good guy" and so become skeptical of complaints about you. ## Double it up by openly making electricity To muddy the above water further, make sure to own solar, wind and battery farms located on the same property as the crypto mines and real generators. This can also be used as a cover to sell to the grid somewhat more electricity than you are actually generating with the solar/wind, if "electricity" is paying more than "crypto", which it will at peak times. Do not do fossil, nuclear or hydro - those are too closely regulated and require too many highly technical staff who might notice. :) For instance the plant engineer who takes fierce pride in running "their" combined-cycle plant at 55.1% and not 54.9%, *is gonna notice* when **their "baby"** is running at 63% :) You want that guy to *not exist*. Whereas it's perfectly fine to have technicians maintaining individual windmills or solar banks - their unit is one of hundreds, they have no sense of pride/ownership of it since it's one of many they service, and they don't expect to see the whole picture. ]

[Question] [ Imagine that human beings in a parallel world evolved with hive mind, so that they can communicate telepathically almost instantly at infinite range. To put thoughts into writing requires effort and not only does it slow down thinking process. It is also hard to describe thoughts in plain words sometime. For this purpose assume all the population are savant, genius and ironically not a psychotic sociopath. Would they develop writing? What are the advantages if any? [Answer] What you describe for a hive mind is also true for a single mind. And yet we all write down things not only for other people, *but also for ourselves*. The hive mind would not need the first reason, but would still need the second. At first it would surely develop specialized members ("druids" or "librarians" or "lore-keepers") to act as memory cells for the whole, as it's immediate and faster than any alternative (supposing it evolved as hive mind and did not become so after a technological and writing stage). The hive mind can literally grow its memory, human beings can't. Much would depend on "copying" speed and fidelity, and resource usage: a book needs no food and very little care per unit, a memory drive requires little in the way of power and environmental control and more, but still manageable, care; a living being on the other hand, while being much faster, has in comparison huge costs. In the end, there would probably be a "L2 cache" made of librarians and a hard storage made of books (and, later, computers?). In absence of computers, the hive mind will probably carefully develop indexes and, as Joe Bloggs noted, reading abilities - data could be "read in" by several readers in parallel and written down also in parallel. The biggest limitation in recording technology will be the "plain words" problem - that of only being able to read back factual details and descriptions, not the "real thing", and the very limited bandwidth; a panorama that can be taken in in a heartbeat still requires thousands of words. Even if surely libraries would be soon be accompanied by picture and map galleries, there would still be a strong need for "druids" remembering complex pictures and sensations, and having these memories copied (how faithfully, remains to be seen) from older, failing druids to newer young storage units. To avoid accidents wiping out parts of its memory, the hive mind would soon see the advantage of a Redundant Array of Inexpensive Druids configuration. (At least until direct brain-to-hardware technology gets invented). [Answer] Permanence and veracity. Thought is fleeting, memory is imperfect, even for a genius. This hive mind might require a Looong term memory store to add to it’s already prodigious mental capacities, both to increase the time it can hold onto a ‘thought’ and how perfectly it can capture information. Essentially the reason people write notes to themselves, or todo lists. In a way: librarians, readers and writers might end up performing the same role as long term memory does in the human brain: permanently storing facts but only retrieving them when called for. Libraries would end up indexed to high heaven to allow for rapid, perfect recall of important facts. I expect writing would be very, very precise for this species, as the only reason it is needed is precise, unambiguous recall of information rather than being expressive (which I suppose for your hive mind is analogous to daydreaming??) So: Your telepaths all know Lojban. ADDENDUM: given the telepaths communicate instantly not all parts of even a single fact need to be written in the same place. If writing evolved along with the hive it’s entirely possible that ‘chunks’of information can be written out in geographically distinct locations and read back in simultaneously to bring the fact back into the collective consciousness, effectively parallelising the hive’s record/recall ability. A non-telepath would find this nigh on impossible to read. [Answer] **TL;DR -- No written language** Hmm, okay, I'm going to have to make some assumptions: * All humans are part of one hive mind, one consciousness * Humans evolved into hive mind *before* evolving intelligence Given these assumptions above... Why would the World-Human have developed a language at all? There's ... nobody to talk to. [1] I think its mentality would be *extremely* different from ours -- it wouldn't just be like everyone having a cell phone in his head. The World-Human would see patterns, quickly and deeply. But I wonder if it would be good at future planning, checklists, and reductionist thinking. I mean, that consciousness would be fractured among so many bodies, it might be impossible to sustain that monomaniacal **focus** so typical of mathematicians, poets, and Java programmers. So, no language. No binary computers (they might make a *mean* analog computer, though!). This creature might be *the* supreme intuitive thinker. It comes up with a problem, the problem disperses among all the bodies, and the answer just kind of "pops up". Not so much introspection here. Nor precise memory, I think. Memory might "come in waves" and be hazy, like your memory of summers as a child. The more I think about it, the more I think that for more "typical" species, dealing with this entity might be a *huge pain in the butt*. [1] One notes that even chatty Earth-humans who are raised by wolves or the like seldom develop language when re-introduced to society. Look up "feral children" for some heartbreaking tales [Answer] Reasons for using written language: * If the population shrinks, some stored information may become unavailable because their capacity of keeping things in their hive mind may shrink proportionally. There needs to be a way to prevent this. * If they would develop disciplines which use number processing e.g. accounting or weather monitoring, there is lot of information which needs to be registered but there is no point of keeping it all in the memory. * If they would develop computers, reading and writing are inevitable phase of interaction with them. (Whether they will later achieve more advanced communication with them, e.g. on mind level or not.) * There are many simple devices which humans need to extend their senses which are to be kept simple and cheap so their information has to be simply *read*, e.g. timer, voltmeter, speedometer, blood pressure monitor, ...you name it. * Some information must come to an individual early also if not requested from the rest of the mind, e.g. individual who enters hazardous area/environment might not inevitably share this fact with others, but they need to see warning signs to prevent an accident. [Answer] I think they are unlikely to develop a written language of words as they do not use words (I assume?) but they might develop a written language for math and physics because everyone can't be Stephen Hawking and work out those problems in their heads. Of course, if your hive mind is akin to networked computers, put 20 or 50 of them together and concentrating solely on this task and they might. If they develop cities for example, they might need a way to mark things. I'm thinking street signs, traffic signs. If they develop technology they might need symbols for different danger warnings. And they could develop art, so maybe their written language would be more like paintings or music notes. [Answer] They might not have a way to write words, but still a way to write numbers. I remember seeing, years ago, a "living history" exhibit in which someone was making barrels by hand. The staves of the barrel (the staves are the long, bowed pieces which give the barrel its "barrel" shape) were numbered with Roman numerals. This way, you could disassemble the barrel for transport, and when you went to reassemble it, the Roman numerals told you which stave went where. So, my guess is that their writing system would basically be a sort of code for labeling things [Answer] An alternative timeline to my other answer: Language has developed at least once. As part of the expansion directive underlying the hive's development, seeder ships were sent to remote stars in the hope that some of them could support new growth. However, one seeder ship had a series of rare mutations in the template genome. The set of mutations both prevented the proper development of the coordination organ and prevented proper full differentiation of sub-units. When this set of mutations (what humans might analogously call 'cancer') occurs within the hive proper, the immune sub-units deal with it swiftly and efficiently, but the nature of the interstellar seeding program means that the template developed in isolation. These developing sub-units, lacking a functional coordination organ, developed a crude form of communication using language, allowing them to progress and shows signs of a pseudo-intelligence, despite being cut off from the one true mind. Unfortunately, as interesting as this cancer has been to observe, it's beginning to show signs of mutating to metastasis. It has started building star ships and exploring its system. If this trend continues, it will be necessary to terminate the experiment for the good of the hive. [Answer] A hive mind race would discover the need for some sort of long-term storage after it had made some sort of useful discovery that is not used often, though when it is needed, it's vital. When most of the cells that initially discovered and used this discovery -- how to make accurate measurements for cultivation, perhaps -- have died, would that discovery still be accessible to the current hive mind? That depends on whether the hive mind still has access to that information after the cells containing that information die. That depends on the structure of the hive mind. Does the hive race has an eidetic memory which can never forget anything? Perhaps it will retain the memory of how to do something but it will also remember every mistake it made in excruciating detail in finding that useful information. I think that some sort of writing system would become necessary. A specialist sub-type drones would evolve (or would be evolved) to handle this useful information. (You can't necessarily call this useful information "true" or even the final development. Useful information is developed only as far as the hive-mind needs it developed. In some cases, it may be extensively developed. In others, it may be stunted. There probably would not be an application of a development in one field being used in another field. It would only take one near-extinction event -- where the hive would have to start over by making the machines that make the machines that make the machines that they currently use -- to show that there is no "useless" information, only information that is not currently useful. In a hive mind, there would be no impetus of war to develop weapons and technology because there is no competition. Psychology would not exist since there is only one being: the hive mind. It might have gotten as far as "it" and "not-it", with not-it being automatically categorized as non-sapient. The concept of sanity would not exist since sanity depends on comparisons. [Answer] Yes, though it wouldn't look anything like what we're used to. Ideas are exceptionally fuzzy, which works really well for making short term decisions in rapidly changing situations, like hunting. It follows reasonably that the hive mind would probably have a similar structure to their thoughts, provided they evolved from carnivorous or omnivorous roots. Written language would be needed once longer term planning, or planning for highly detailed projects, is needed. Writing something down makes it easier to reason about, identify missing details, etc. This would be especially critical for the hive mind if underlying assumptions are implicitly shared, as it would make catching errors by getting a second option near impossible. The hive mind wouldn't have access to an equivalent to editorial or peer review. The language itself wouldn't be used to transmit ideas as much as refine or store them (as noted in other answers, a hive mind doesn't imply perfect recall), so having many forms of writing would be possible. The language used for long term knowledge storage could be vastly different from the way plans are initially recorded for consideration, which could be very different from the way refinements to that plan would be recorded, which could be jarringly dissimilar when compared to the notation used to flag errors. [Answer] I find it hard to imagine a telephatic hive mind to develop a spoken language at all - I find it even hard to imagine they would develop something like the concept of individuality - in case anyone's thoughts are yours and vice versa, none of this is really necessary from a Darwinistic point of view. I would guess they'd store collective information just like some species of ants, for example, store food - Inside members of their own hive. Just like those ants developed workers, warriors and queens, a human ant hive would develop a subspecies just to store the collective information - Specific individuals that do nothing more than train and provide their long-term memory to the hive. In order to work around imperfections of this biological storage media, they would probably even implement concepts of a "biological RAID server", storing information in redundant places in order not to forget anything. Telephatic access to that long-term storage would most probably be instant, so no need for shopping lists and anything in a written form. Even street signs are entirely unnecessary when you can instantly "know" where you are by accessing this collective knowledge. [Answer] I'm assuming that a hive mind has no spoken language and no need for one as such I wouldn't expect them to have a written language of words the way modern humans do. I would expect that a hive mind with a sense of time will have to keep notes though, because humans have a finite memory. I'm not thinking an encyclopedia or history book or even hieroglyphics but more like the wall scenes found in Egyptian temples that depict battles, rituals, and coronations etc... in a strict stylised format. A history book written in an art language governed by strict rules, stable over deep-time, that can be scaled according to the material format being used and can depict all the bits that the hive considers worth noting at the time. The existence of this history is based on the ability of the hive mind to learn that "those who forget their history are doomed to repeat it" otherwise it doesn't even need to keep track and has no use at all for records of any sort, and thus no physical medium of communication verbal or written would be needed. [Answer] If the hive mind evolves in parallel with the development of 'humans', I think it's highly likely that it will evolve specialized roles for the biological sub-units making up its mind and body. Similar to ants or bees, they will be fed special foods or given other specific stimuli which result in differentiation on a biological level. Actuator sub-units would become stronger and perhaps even develop specialized limbs, say, with claws. Breeder sub-units would be kept protected and have limited mobility, spending all their time breeding. And then you get to the mnemonic/analytical sub-units, whose job would be to help store and process knowledge. So, if language does develop, it will likely only apply to these latter sub-units. Actuators, breeders, care-takers, transporters and sensors would likely never learn language. For those sub-units that do use it, it will likely be highly technical and specialized, with lots of short-hand and high symbolic density. After all, there's no need to try to describe context by verbose analogy, since all sub-units contribute to the same overall context. It's only necessary to more efficiently encode excess data for later access as needed. If the one true mind eventually discovers apparently 'intelligent' life on the scale of one of its sub-units, it might eventually develop more generalized language in an attempt to experiment with these strange forms. Much as we study molecular biology and adapt structures like CRISPR-Cas9 to manipulate genomes and observe the results, the one true mind could decode this inefficient inter-sub-unit communication protocol that has allowed these disparate forms to coordinate, albeit at a crude level. The scientific sub-units would hypothesize that they interact via vibrations transmitted through the air and even electromagnetic signalling in some cases, providing a wealth of interesting possibilities for experiments. [Answer] Lots of great answers already. One thing that looks like it's been missed is that language influences the way we see the world. If a Hive mind existed, how would thoughts be shared between entities? Specifically, if I see a boar over there, in what format does that information arrive at my hunting buddy? Do they see a picture? Does their map of the world gain a new entity where I see the boar? Or do I send them language indicating what kind of animal and where? There is ample evidence that language affects the way we see the world. I'd change your statement from "It is also hard to describe thoughts in plain words sometimes" to 'It is hard to describe thoughts without words'. If creatures communicate, they will use language. If they forget or need to share that information, they will write it down. [Answer] Isn't the human brain already kind of a hive? Maybe the individuals of this community would behave as neurons so all the whole information is everywhere and nowhere at the same time. [Answer] If they developed a "Distributed" storage system they would probably be able to preserve and pass down memories so why would they record them... In fact the entire concepts of mortality and individuality may not occur to them since everything an individual ever did is completely preserved and shared. This leads to some really interesting possibilities... You could probably spend a lifetime just delving through memories instead of creating your own. Maybe this is why we didn't evolve this way :) If a good deal of your race was wiped out or a group separated by enough space they would probably start to lose random memories which would be a really weird concept to a race that has every memory available at any time. ]

[Question] [ Help! I've been transported back in time to London in 1303 AD. After saying hi to the flock of other worldbuilders who have inexplicably travel back in time to Medieval Europe, I decide to set out to get something to drink. Luckily, there are plenty of things to drink in the middle ages. Three days later, I'm fed up with the fact that all of those things are beer. I'd like to obtain some clean water for drinking and cooking, but the city I'm in is *filthy* and nobody has any idea why feces and drinking water should be kept far apart. With the rest of the worldbuilders off trying to prevent the black death from happening or giving leaders modern military hardware in order to sway the outcomes of pivotal battles, I'm left to solve my water worries on my own. What's the best way for me to obtain fresh, safe drinkable water in a medieval city? What sort of technology or resources should I gather to make sure the act of drinking doesn't lead to my horrific demise to one of the [many,](https://en.wikipedia.org/wiki/Cholera) [horrible,](https://en.wikipedia.org/wiki/Dysentery) [diseases](https://en.wikipedia.org/wiki/Typhoid_fever) that are doing their best to kill my new neighbors? I'm also a fairly empathetic person, so bonus points of the solution is scalable to the whole city. [Answer] While distilling leaves you with absolutely clean water, it is very costly. The constant need of burning material is a real problem if a bigger amount of water is required. But fortunately, there is another method that is way cheaper. **Filtering:** Every citizen can build his [own water filter](http://www.wikihow.com/Make-a-Water-Filter), with gravel, sand, charcoal and some cloth: [](https://i.stack.imgur.com/bdufC.jpg) This filter clears out most of the dirt and leaves you with clean water. On a bigger scale this might look like this: [](https://i.stack.imgur.com/K21H5.jpg) To use it, simply pour your water through a few times. The water you get will be very clear, though still contain bacteria. To get rid of those, boil it for about three to five minutes. While you still need burning fuel for this, it is much more cheaper to boil it for a few moments than condensating it completely. Another advantage of boiling collected water instead of full distillation is, that the minerals that the water has collected won't get lost during the process. **Bonus: Rain-water** If using rainwater like in the second image, the water should be relatively bacteria-free and drinkable from tap. Rain-water is pretty similar to distilled water. After condensating as clouds, [collected rainwater has had its only opportunity to get dirty while falling down to earth](https://chemistry.stackexchange.com/questions/2495/what-is-the-difference-between-distilled-water-and-rainwater), picking up whatever is in the air. Back in the day, where chemical air pollution wasn't a big thing ([usage of coal has been prohibited in 1273](http://www.air-quality.org.uk/02.php)), that is no problem for you. **Finished concept** So, the final plan for your city-wide water supply would be to provide every household with a big water barrel that collects and filters rain-water collected from the rooftops. For the case in which the collected rain-water does not suffice all your needs, you can filter and boil water you collected from wells or streams. Also, as [T.J. Crowder](https://worldbuilding.stackexchange.com/users/1965/t-j-crowder) mentioned (thank you!): > > After 2-3 weeks once the hypogeal layer has formed, you probably [don't need to boil the result](https://en.wikipedia.org/wiki/Slow_sand_filter#Method_of_operation). Note that it's necessary to renew that layer periodically as it gets too thick (I don't know how often; not all that often is my impression). > > > As he mentioned, after a while a biofilm will form. > > The surface biofilm is the layer that provides the effective purification in potable water treatment, the underlying sand providing the support medium for this biological treatment layer. As water passes through the hypogeal layer, particles of foreign matter are trapped in the mucilaginous matrix and soluble organic material is adsorbed. The contaminants are metabolised by the bacteria, fungi and protozoa. > > > So you are not even required to boil your water anymore. But be careful, as you need to renew the layer every now and so often, as > > Slow sand filters slowly lose their performance as the biofilm thickens and thereby reduce[…] the rate of flow through the filter. > > > [Answer] A fire heated distiller like Ville Niemi's answer is a good idea, but if the fuel and constantly tending the fire aren't practical, you could try a solar distiller. Shouldn't need any space-age materials, just some glass & metal (avoid lead solder!) or wood containers to hold water in. [](https://i.stack.imgur.com/ORaU4.gif)[The Solar Water Still Challenge](http://www.techedmagazine.com/node/2609) The guy in the videos on [this page](http://diy-alternative-energy.com/build-a-solar-water-distiller/) got 3.13 cups of water per day from 3.3 sq.ft of "glass area," or about a cup of water per day per sq.ft of glass. --- Actually, if you're worried that **glass** is too expensive or scarce, you can make an old-fashioned solar oven with some shiny metal. The above design *might* work with a dirty/dark piece of metal on top, it would get hot and indirectly transfer heat to the water, but probably not as efficiently. A **solar oven** would be perfect to put a regular distiller-type pot of water in, with the tube leading out to the "distilled water" container (just like a regular stovetop distiller, but no fuel or fire. Similar to this: [](https://i.stack.imgur.com/GxaVq.jpg) Even a basic box with a shiny interior & lid may be good enough: [](https://i.stack.imgur.com/gkXRq.jpg) Or a more basic "hole in the ground" still ([forum link](http://www.democraticunderground.com/112785412)) like this may work too, you may not have access to clear plastic sheets, but a clean dark cloth or tarp *may* work also (and you don't have to worry about space-age plastic chemicals leeching into the water either). [](https://i.stack.imgur.com/dPoeq.gif) If there's enough space around people's homes in the city (no high-rises then, but I'm not sure a medieval roof would support a tank of water) they may each be able to have their own solar still & make their own water, no fuel or fires required. [Answer] ## Pre-treatment London is built on clay. Clay is highly resistant to water so flow occurs between seams in clearly defined aquifers. As a result soil filtration is limited. To rectify this situation, around the well plant *Chrysopogon zizanioides* also known as Vetiver in concentric rings at 15cm intervals and 15cm (6") between rings. Allow two years for the fine dense roots to descend 5m (16') and overlap. The more rings you plant, the better the filtration. This on its own will substantially protect the well from not only from fecal pathogens but also heavy metal and other inorganic contaminations. However, it is still far from a modern notion of potable. ## Settle Build a settling tank with four compartments, each overflowing down a pipe to the bottom of the next stage. The bottom of each compartment should steeply taper to a pipe with a dump valve for quick and easy flushing of sediment. ## Filter Build a sand filter. Feed the top from near the top of the final stage of the settling tank, tap the bottom. Water exiting the sand filter will have residual turbidity. A charcoal stage would resolve this but would be an expensive nuisance to maintain. ## Clarify There are various options. * Centrifuge. On a large scale this could be powered by waterwheel. The centrifuge chamber should have a spiral rill to transport sediment and to capture it when spun down. Output will be less murky and fit for bathing and washing clothes. Goes some way to removing larger pathogens provided the tap is correctly positioned. * Fines. Certain clays will clarify. Look up "fines" in the context of wine-making. Not a large scale solution. Does nothing for pathogens. * Distil. Expensive but very effective. Use for actual drinking water, not for washing or bathing. * Microfiltration. + Charcoal and muslin. Expensive, high maintenance, low throughput, not good enough for pathogens. Does clarify. + Filter through a raised sealed garden bed again containing vetiver. This should be long and narrow, to maximise travel through the root mat. Water emerging from 2m (6') of this will be clear and "sweet" and certainly a lot safer to drink than anything else short of distillation or brewing. Very suitable for washing and bathing. For drinking purposes either brew or boil small quantities on demand. Vetiver foliage is dense and sharp and will form an effective hedge around your well. It will reach 2m but can be neatly hedged and the clippings used for vermin repellent thatch or mulch. There are detailed documents on the application of *C.zizanioides* to well protection as well as riverine and [slope](http://www.vetiver.org/NIG-soilcon.pdf) stabilisation and [phytoremediation](http://www.ncbi.nlm.nih.gov/pubmed/19810597) (use of plants to rehabilitate contaminated soil or water). Modern applications of well protection [can be found in Haiti](http://vetiverlatrine.org/index.php). I'm pretty sure this is also done in Tonga but damned if I can find anything about it online. It's also widely used to [contain contaminants on mine sites](http://www.vetiver.com/AUS_mines.htm). In an earlier revision of this answer I incorrectly attributed documentation to the UN. In fact it was sponsored by [World Bank (see p12)](https://www.researchgate.net/publication/265032101_VETIVER_SYSTEM_APPLICATIONS_Technical_Reference_Manual). ## Risks *C.zizanioides* doesn't like frost. It may be necessary to find another plant with similar root characteristics but more suited to lower temperatures. [Answer] You could try sinking wells and just boil all the water you draw. Even in the middle ages people didn't typically excrete in their wells [Answer] You can build an aqueduct and bring fresh clean water to the city. The romans did it and were very successful. [Answer] If it has to be in a city, distillation. It wastes wood or coal so it might get expensive but otherwise it is simple enough with water. Just boil (unclean) water and gather the steam with something made of metal in a way that makes condensed water run into a separate (clean) water container. You can maybe pay the fuel costs by distillation of alcohol. While it was known in Europe at this point, it probably was not yet exploited commercially. So there might be a business opportunity. And the alcohol can be used as disinfectant, which might help with your disease issue somewhat. [Answer] Go for tea or coffee, both of which require water to be boiled. As well as the benefits of caffeine, you also kill off the pathogens. Your mediaeval friends haven't discovered tea or coffee yet? Time to go anachronistic and kickstart them early. Coffee is probably easiest - the Crusades have only just finished, and even at their height there was still substantial trade between the Arab and Christian worlds. This will be expensive, mind you, but it should be achievable. [Answer] The Romans solved this problem by building aqueducts to pipe in potable water from uncontaminated sources. It's a major civil engineering project, but by the 1300s European engineering technology was well up to the challenge. The Great Conduit was built in London in 1245 so it seems obvious that these kinds of major civic works were being undertaken and that the importance of uncontaminated drinking water was well-understood. The biggest public health improvement a time traveler to 1303 could do is introduce germ theory ~250 years early. Being able to build a microscope would help enormously in overturning the fallacious medical practices of the day. Convincing people that disease is caused by microorganisms and not an imbalance of humors and/or evil spirits would be a significant challenge. [Answer] Well, it's sort of similar to the distillation suggestion, but it's not quite the same - a dehumidifier (or condenser). Warm air holds more water, and when it cools, water is displaced - and as a result, it'll be nearly clean. At a basic level, all you need to is blow warm (and damp) air at a cold surface. Natural air flow can do that, and all you need do is provide the 'cooling' surface - something dark coloured in shade will radiate heat and have a cooling effect - and if you do it right, you can actually use the temperature differential to generate a convection airflow - cold air will fall, displace it's moisture, and cause 'warm' air to be drawn in from above. Or if you want something a bit more high tech, there's: <http://www.gizmag.com/airdrop-wins-james-dyson-award/20471/> You might manage to accomplish something similar with medieval tech. Or perhaps: <https://en.wikipedia.org/wiki/Air_well_(condenser)> [Answer] You could make a dripstone 'vase' from limestone like this one: <http://sydneylivingmuseums.com.au/stories/elizabeth-farm-dripstone>. Contaminated water is poured in and fresh clean bacteria-free water slowly seeps out just the way it does in caves. A pan is placed below to catch the dripping water. [Answer] **Could you drill a really deep well?** i.e. a tube well or borehole well. You would have to develop the drilling technology from scratch. But what you know, that the locals did not, is that London sits atop an Artesian basin. Drill down through the clay strata (about 400 ft from memory) and you will hit porous chalk, out of which will gush large amounts of pure, highly calcified fossil water. Clay is soft and easy to drill. Note: The mediaevals could dig really deep wells but had to stop at whatever depth they first hit water. That will happen before you reach the chalk. You'll have to drill. Oh, and your technology will then be spread to other parts if the country where they may bring water naturally contaminated with Arsenic to the surface and poison themselves with it. You'll warn them that only water out of chalk is guaranteed safe to drink, but they won't listen. ]

[Question] [ Imagine a theoretical scenario where I am transported backwards in time 500 years with nothing but a mobile phone containing all of human knowledge. Clearly I want access to this valuable resource but darn I forgot to bring my charger. Using only things readily available in the 1500s (and let's say in the area of Europe, although I'm happy to have location moved if that would make a big difference to your answer), how would I construct a device for charging the battery on my phone? I'm not overly fussed about efficiency, i.e. time to charge is not really an issue. [Answer] You could emulate Volta's pile if you could find some zinc and copper metal, and some acid, however the purity of such items might be pretty questionable. Which means you might get more voltage than you expected and damage the phone, with no possibility of repair. The cells Volta made produced about 1.1V so 5 of them would be about right (perhaps a bit high). Of course if you had a 7805 or similar voltage regulator you could just add a whack of cells and regulate it down, or if you had a voltmeter you could check it, but if you're assuming that kind of preparation you may as well bring a solar charger along with you and use the sun. If you could get access to some thin wire (perhaps a master jeweler would have drawing dies) and some lacquer or enamel for insulation, plus some iron and other bits you might be able to make a crude galvanometer which would allow comparison of a charged battery to whatever you are trying to come up with. Given the likely high cost of reasonably good supplies in that era, probably you'd best start by finding a patron to fund the operation. And making yourself understood might be difficult. --- Edit: A better approach might be to build a Volta pile or similar to add up to a nominal voltage in the 250 volt DC range. That could then be connected to a standard charger (despite being DC the chargers will still work). The enormous advantage of that approach is that the chargers have a **very** wide tolerance of input voltage, from 85 to 250V RMS or so, so anything from about 110VDC to 350VDC should work (square root of 2 relationship, and some ripple allowance). A 250 cell Volta pile should provide sufficient voltage - nominally around 275VDC (and lots of energy if the cells are of reasonable size) without taking risks on the phone itself, and would be very safe for the charger too. **Not** so safe for humans, easily lethal, which might make for an interesting twist to a story line. While, technically, this is not "building a charger" as the question asks, I think it well answers the spirit of the question. Then you could go ahead and find some monks (or other literate people with time on their hands) to begin transcribing from PDF to manuscripts, assuming you don't want to keep all this knowledge to yourself. [Answer] Don't try to charge the battery inside the phone. Build a 10 cell [lemon](https://en.wikipedia.org/wiki/Lemon#History) [battery](https://en.wikipedia.org/wiki/Lemon_battery) with [copper](https://en.wikipedia.org/wiki/Copper#Modern) and [lead](https://en.wikipedia.org/wiki/Lead#Middle_Ages_and_the_Renaissance) electrodes, which produces ~4.35V with a maximum current of about 1~5mA. Remove the battery from the phone and connect it to your lemon battery with the correct polarity (copper electrode is positive). At this low current there is no risk of damaging the battery until the voltage gets over 4.2V, so charge it until it has enough capacity to be usable but not risking over-voltage (eg. 50%) using the phone to tell you the state of charge. At 1mA (24mAh per day) this will take several weeks. [Answer] You could build a *dynamo*. One of the simplest designs for a dynamo is the [*homopolar generator*](https://en.wikipedia.org/wiki/Homopolar_generator), also known as a Faraday Disc. [](https://upload.wikimedia.org/wikipedia/commons/thumb/1/19/Faraday_disk_generator.jpg/220px-Faraday_disk_generator.jpg) You'll basically need a: * magnet * copper disk * commutator brush Line enough of them up and you should be able to produce the necessary voltage and current. With a skilled jeweler, you could then create gold wires to hook up to the +V and GND pins of the USB connector on your mobile phone. The harder part of the problem is generating the correct amount of voltage/power to charge the device. Fortunately, the battery-charging circuitry on mobile devices should protect it from too much over-voltage, and if you use a galvanometer in series with one of the connectors, then you should be able to see the point of "deflection" where the voltage has reached the threshold to allow current flow. [Answer] It is possible to make a battery using electrolytes from vinegar, apples, etc. Depending on the type used you can get different voltages. If they do not match 5 V, put them in a series or parallel combination to get close enough to 5 V. A side issue is to create a Volt meter to measure voltage output (you don't want to damage your mobile phone having a too large voltage). However, calibrating it might be another problem (see remarks of C1sc0 and JRE below). This way it should be possible to get a 5 V electricity source (which is DC). See e.g. <https://www.cool-solar-stuff.com/solar-diy/diy-vinegar-battery-lights-led/> What you need is: * zinc or aluminium; I'm sure aluminium was not present in 1500 (confirmed by JRE, production from 1824), but zinc might be (not the element, discovered in 1746, but the alloy was known for much longer) * natural products should not be a problem * copper wire, also available at that time * plastic bottle caps, not present, but I'm sure anything made of non metal can be used (maybe wooden cups?). Check comments of Bytes, Dirk Bruere and analogsystemsrf below for details/alternatives. [Answer] You've picked a **very** difficult thing to do. Besides the electrical problems, you also have the mechanical problems of making the connector. USB micro connectors are **very** precisely made, and you are going to have to connect wires to some very fine pins. I think what you want is beyond what you could reasonably accomplish. I mean you've got like two days of battery time before your phone dies and you lose access to all the information you need to build a charger. You won't be solving all the inherent problems and getting something made quickly enough to do you any good. I'd suggest you make it a bit easier. Take a charger with you. The typical wall wart to USB charger you get with your phone. Now all you have to do is to get enough voltage to it so that it can operate. "But my charger needs AC," you protest. Well, it is designed for AC. Most of them **will** run, though, if you give them enough DC. Build voltaic cells as described in the other answers here. Stack them to get about half the lowest rating of your power supply, and add stacks in parallel to get more current. Connect your crude battery to the AC input of the charger. It will then reduce and regulate the voltage to the 5V your phone needs. Building **just that part** will also take longer than your phone battery will last without recharging, but the task is simple enough that you can accomplish it without access to the data stored in the phone. It will take you a good while to accumulate the metal pieces, and build your batteries. You don't have to worry too much about what kind of metal. Pretty much any two metals can be used in a battery - some combinations are better, some will mean you need really tall stacks to get enough voltage together. You just need to be sure you really only have **two** types of metal in your battery stacks - impure metals can cause you lots of problems. There's no insulated wire available, so it'll be much easier to attach to the AC prongs on the charger than to the USB pins. The whole contraption will be dangerous as F. A DC voltage high enough for this trick to work is high enough to be fatal to anyone who manages to touch the (exposed and uninsulated) plus and minus poles of the battery. Once you have a usable way to charge your phone, you can look into building something better - with the ability to keep your phone operating until that something better is finished - and expect **that** to take years. --- The charger can operate from a lower voltage, but it might not like it. You'll have to weigh getting information from your phone against the chance that your charger will croak the next time you hook it up to the battery. [Answer] A lot of these answers are forgetting something very important. # The phone contains all of human knowledge. Assuming you are transported back with a full battery, look up and write down everything you can on electrical engineering in the time the phone is still running. Once you have written down all of the necessary information, get to work in building whatever you need. * Gather the needed materials, without showing the phone around and without bringing too much attention to yourself * Find somewhere isolated and safe so you can build your machine without being discovered * Build it and use it to charge whenever you need it * Once charged, use the phone's human knowledge to continue improvements, if necessary [Answer] Depends on the phone. If you give an LG G7 One 5 volts, it will happily charge away at whatever current it can reasonably pull. As other answers state, coming up with 5 volts (ish) is certainly doable, and the internal resistance of a battery from that timeline will take care of any over-voltage you accidentally create from impurities. If you give a Samsung Galaxy S7 or a Blackberry Dtek 50 5 volts, it will start trying to ask the charger if it's a samsung charger/blackberry charger etc and will leverage the USB protocol to do so. Opinions about this aside, this makes it nearly impossible to charge these phones from a diy standpoint (there's no way you could forge silicon to do USB communications in 1500). If you can get inside the phone (go find a jeweller/watchmaker and wow them into making you a torx bit with files and high carbon steel), you can relatively easily build a charging system that will charge the battery, and manually modulate the current/voltage by building a potentiometer with a strip of carbon/lead from a pencil (is charcoal conductive enough for this? A quick google says so). Take another pencil's lead to solder some leads to the battery (a mild steel screwdriver in the fire for a while as an iron, or any chunk of steel with wood nailed to it for insulation) and make some rosin by boiling pine sap (thanks again, google). I imagine from this answer you can tell the different phones I've had over the years. Edit:I was wrong, my phone charges(albeit slowly) from a dumb charger (data lines floating). It will not recover from dead (I tested this with the dtek 50 which died overnight) without the original charger. This is an important point and could factor in. The phone mustn't die completely at any point. [Answer] Any battery in a phone removable or not is a module with it's own protection circuits which will cut it off when the voltage/current/temperature is out of range. So it is safe to charge/short circuit the battery directly. The battery's voltage range is like 3.0-4.3V which is wider than the phone input port range which is like 4.75-5.25V so it is easier to charge the battery directly with a poor power source. The most import advantage of battery is that it is a voltage source at normal state (not cut down by protection circuit), i.e. it is a voltage potential plus a low resistance which is <0.1Ohm or even <0.02Ohm. So you can just drive the battery with any power source through a large enough resistor and it will be charged since low resistance battery plus large exteral resistor means that voltage of the battery contact and the current will fall in the range reqired by the protection circuit for a very high chance. On the other hand, the phone charging port is a high resistance port by default, it is just some capacitor and voltage sensing circuits. It only begin to charge the battery when the input voltge is in range like 4.75-5.5V. This means that with a poor power source (e.g. large resistance/low loading capacity/unsure voltage), the chance that the phone will beginn to charge is low. Even the phone begin to charge the battery, since most phone use switching power to charge the battery, it is the charging circuit that decides how many current to draw from the power source, this means that the chance of overload of the poor power source is high,and once the input voltage falls bellow like 4.75V, the phone will stop to charge. On the other hand, if you charge the battery directly, the current draw only depends on the battery's resistance and the external resistor you use, you can limit the current with external resistor. This also means that you can't use resistor when charging the phone port. External resistor mean that you can use a much wider range of voltage and unstable power source. Some answers mentions the connector problem, it is just impossible for you to wire out a micro-USB or type-C or Lightning connector. Like @Zero's anwer, remove the battery and charge it. Most phone have non-removable battery so the first difficult is to remove the back cover of the phone, you may need to somehow destroy the back cover for many cases but without rendering the phone fully unusable. With some sort of 3.5-6V(or even higher) poor power as mentioned by other anwers, the next tool needed is a resistor which can be made from long thin conducting wires which I'm not sure is available. You can begain with high resistance and check out wether it works after charging for a while and cut the wire shorter to try low resistance. No need to worry about over voltage or over current, unless the voltage is too high and the resistance is too low and you break the maximum rating of the battery protection IC. [Answer] Why can't you take out the battery and connect it to Volta's pile (4 of them), that is 4.4V when fully charged, this is more than enough for Li-Ion battery operating at 4.2V, you can ignore 0.2V overvolt I'm sure battery can handle that. As soon as you connect pile to battery, pile's voltage will drop. [Answer] If we have a phone with all of human knowledge, then I’m surprised that nobody has suggested searching the Internet archives on the phone for the Reddit topic where this question was asked and the answers given. [Answer] Since the device has all human info, I'm assuming that it is advanced enough to have inductive charging. Inductive/wireless charging would be safer than using a USB connection and is simple to build from wires. Combine that with the battery ideas and you could charge a phone until enough wire and other basic materials could be acquired to build a small hydro-electric generator. One of the wind turbines for pumping water from wells in northern Europe could also be adapted to generate power. [Answer] > > ...with nothing but a mobile phone containing all of human knowledge > > > I know this is all just a thought experiment, but it's worth pointing out that although we have ACCESS to "***all of human knowledge***" via things like Google, that information is contained on some very HUGE server farms, not in your cell phone memory itself. [](https://i.stack.imgur.com/7inLG.jpg) Even applying Moore's law to the increase of memory storage capability, your mythical "cell phone" device capable of storing **all** of human knowledge is not going to exist for a few hundred more years, especially considering that the amount of "all" is ever increasing as you try to get there. And even if that happens, I seriously doubt it will be possible to power it with 5VDC. Right now Google has about 1 million servers, and assuming that each one consumes about 850W of power, all of that knowledge needs around ***850 MEGAWATTS*** of power to make it accessible. ]

[Question] [ Encrypting texts is a very old technique, which is known already from the time of the Romans, if not earlier. Now a simple text cypher is easily done with low-tech means, as long as those trying to break the code also have to rely on low tech. Now medieval maps were often secrets. Therefore one might imagine that some medieval king wants his maps encrypted as well. Now it's of course easy to encrypt names using any text cypher, and moreover you may use non-standard symbols for landmarks. However, those would probably be easy to decode for anyone who is familiar with at least a small part of the mapped landscape. Therefore an effective encryption would need to encrypt the actual map, including the positions and relations of the landmarks to each other. Therefore my question is: How might one encrypt a map? The conditions are: * Encryption/decryption should be doable with medieval means. * For someone familiar with the encoding, it should be possible to decode the relevant features in little time, using only a minimum of tools (the map should be usable on travels). * The encryption should be non-obvious to someone who is familiar with the mapped region, but doesn't know the encoding (that is, the encryption doesn't need to withstand modern cryptanalysis tools — the Caesar code wouldn't withstand them either — but it should not allow someone not knowing the code to look at the map and say "I recognize this region"). * In response to Keith: The map should be detailed enough that you can find your way, and can identify special spots (like the spot where you want to position your army, or the spot where you have buried the secret chest). However, the map can be amended with written information for details (for example, if it allows you roughly to get to the place of the buried chest, the exact placement could be written in a text referring to the landmarks around), so there's no need for extreme precision. [Answer] You could always do it the way Robert Baden-Powell (the founder of the Scout Movement) did when he was posted to Malta as a spy, Draw maps as butterflies or some other animal. This does not require any special tools to decrypt other than to merely look at it. Those unfamiliar with the concept will see only an image of an animal / bug. In theory this could still be used today depending on how many people know what you are up to. In particular, in the included image you can note that "secret spots" (in this case gun emplacements) are marked on the wings of the butterfly as patterns further hiding the real intentions behind the image. Essentially if you could produce a convincing enough image of an animal that could have features that stand out only to the recipient or those knowing the code, you would have both an alibi for carrying a "map", as well no real proof that what you are holding is a map. ### Links to Sources: <http://publicdomainreview.org/2013/07/10/robert-baden-powells-entomological-intrigues/> <http://pinetreeweb.com/bp-adventure02.htm>     [Answer] **Folding.** Make a large map with large erroneous portions that become hidden with proper folding. This will confound even someone familiar with the area. "That looks like such and such river, but it doesn't have this adjacent mountain range..." Yes, creasing could give it away, so the solution there is to use separate pieces of different maps which, when layered and oriented properly, reveal the real map. The cipher would be something akin to overlapping the dot marking certain towns or geographical landmarks. Basically this is a map made of a collage of maps. I can't find a proper example, because maps aren't usually designed to do this, but it might look something like this when the erroneous sections are folded away:  Folding is preferred for the single or separate maps to produce the final map. Otherwise you just have the complete map cut into pieces. The maps can otherwise contain many folds to hide the proper ones and be flattened when not in use to avoid capture of the proper folding. Adding other maps which play no part in the final map will serve to further confuse anyone who captures them. [Answer] Anamorphic drawing  uses a reflecting surface to draw/view a scene (or a map) The shape of the reflecting surface is the cryptographic "key" that would allow the information to be extracted, while hiding it from anyone lacking the correct reflector. [Answer] Encryption requires a key to decrypt. Lets work with that assumption. Draw a full map to act as the "key", and cut holes and lines and shapes in it that ruin it. Draw a second full map by first overlaying the cut out pieces of the key on top of the second map. For each section that is not covered, draw fake details and information into it. Then, remove the covered sections and replace it with legitimate information. Now, only when you have both the key and the map are you able to make any sense of the two - the key is full of holes and as such unusable by itself, and the map is full of fake sections that are covered up by the key when applied correctly. [Answer] ## Color Encoding When the map is made, add landmarks and terrain features using a specific color. Accompany the resulting map with a set of glasses with [color-filtering lenses](http://www.sciencefriday.com/blogs/01/31/2014/see-the-world-through-color-filtering-lenses.html?interest=5) designed specifically for that map. Medieval techniques would cause each map and each set of glasses to be slightly different, making perfect decoding of unassociated map-glasses pairs to be difficult and/or confusing. ## Image Distortion Instead of using color filtration, the maps could be made using image-distorting lenses, much in the same way as the mirrors at a fun house. If the cartographer makes unimportant/important parts of the map using lenses that make everything wavy, the resulting hodgepodge of real and wavy parts can easily cause confusion. [Answer] You could draw parts of the map on pieces of thin paper. The pieces would need to be folded and stacked in a specific way. Then, the map is lit from the back somehow (sunlight, sky or firelight). This reveals the map. If you've seen the original Iron Man, Tony Stark uses a method like this (without the folding) to disguise his plans for the first Iron Man suit he made in the cave when he was captured. When the pieces were arranged correctly, it showed the full suit, but otherwise they just looked like random drawings. (Sorry, couldn't find the link..) [Answer] **Hide the map in what looks like a coded message of text.** For instance, take the following text with various capital letters: > > AT VEro eos et accusamus et iusto odio dignissimos ducimus qui > bLAnditiis praesentium volupTAtum deleniti atque corrupti quos dOLores > et quas molestias EXCEpturi Sint occaecati cupiditate non proVIDENT, > SIMIlique sunt IN cULpa Qui OFficia DEserunt mollitia animi, id est > laboRUm et doloRum fuGA. et haRUm qUIDEM rerum facilis est et expeDITa > distinctio. Nam liberO tEMporE, cum soluta nobis est eligENDI OPtio > cumque nihil iMPEdit qUO minus id quod mAXIME placeat facerE Possimus, > omnis vOluptas Assumenda est, omniS dolOr repellendus. tEmporibus > autem quibusdaM Et aut officiis DebitIs aut rerum necesSITatibus saepe > eveniet ut et voluptateS REPUdiandae sint et molESTiae non recusandae. > itaque earum rerum hic tenetur a sapiente dElectus, ut aut reiciendis > voluptatibus maiores alias consequatUR AUt perferendis doloribus > asperiores repellat. > > > Apply the cypher which says to split lines after a certain number of characters at the nearest space: ``` AT VEro eos et accusamus et iusto odio dignissimos ducimus qui bLAnditiis praesentium volupTAtum deleniti atque corrupti quos dOLores et quas molestias EXCEpturi Sint occaecati cupiditate non proVIDENT, SIMIlique sunt IN cULpa Qui OFficia DEserunt mollitia animi, id est laboRUm et doloRum fuGA. et haRUm qUIDEM rerum facilis est et expeDITa distinctio. Nam liberO tEMporE, cum soluta nobis est eligENDI OPtio cumque nihil iMPEdit qUO minus id quod mAXIME placeat facerE Possimus, omnis vOluptas Assumenda est, omniS dolOr repellendus. tEmporibus autem quibusdaM Et aut officiis DebitIs aut rerum necesSITatibus saepe eveniet ut et voluptateS REPUdiandae sint et molESTiae non recusandae. itaque earum rerum hic tenetur a sapiente dElectus, ut aut reiciendis voluptatibus maiores alias consequatUR AUt perferendis doloribus asperiores repellat. ``` Throw away lower case letters and replace them with spaces, replace the capital letters with some character. ``` XXXXX XX XX XX XXXX XX XXXXXXXXXXX XXX XX X XX XX XX X XXXX XX XXXXX XXX X XX XX XX XXXXXXX XXX XX XXXXXX XXX X X X X X XX X X XXX XXXXXX XXX X XXXXX ``` The simple map is revealed. Meanwhile any captured documents would have enemy spies trying to decipher some encoded message, when no such message exists. [Answer] We can make some sort of jigsaw puzzle with square pieces without holes and pinches from map.  And put special symbol on the bottom side of the map. Let us consider the "MAP\_OF\_CITY" is the key. So, the first piece is the one with "M1" on bottom, the next is "A1", third is "P1" and so on, than, after "Y1", the "M2", than "A2" and so on. Of course we have pieces that are fake (for example, with letter of "W1","W2" and so on). So, the map can be assembled quite fast, and pieces can be quite small for images to be usefull. Also the map can be something, that do not looks like a map - like [Ammassalik wooden maps](http://www.reddit.com/r/MapPorn/comments/2rb335/ammassalik_wooden_maps_carved_tactile_maps_of_the/)  [Answer] Create a map grid with letters on one axis and numbers on the other, ex: A through Z on top, 1-26 on the left. If you need finer details, you can increase that, say A through AZ and 1-52. Now turn your map into a written description: > > The river is an eighth of a mile wide and runs from A3 to E7 to M6. It widens around L6 and there is a crossable ford at D5. The trade road runs from A5 through... > > > Now you have a written description, and you can use standard encryption techniques on that. You have two options with that: 1. Encrypt all of the text. This is the most secure, but takes the longest to decrypt. 2. Only encrypt the coordinates. This is less secure, because people will be able to gather rough details without the code. But it also makes it much faster to decode and reverse to the correct coordinates and recreate the map. [Answer] Love this question, and there are some ingenious answers already. I haven't checked the engineering on whether this would be possible, but I'm thinking a [Pantograph](http://en.wikipedia.org/wiki/Pantograph "Pantograph") with custom geometry to transform the map outlines; the transforming element could be replaceable for different encodings.  So, General 1 creates his master map. It is transformed onto another sheet, which is given to Disposable Soldier 1 to take to General 2, who uses the previously agreed upon pantograph element to reconstruct the original. Doable with some bits of wood and a charcoal stick; although the transforming element may have to be more accurately made. [Answer] **Invisible ink** It is is not exactly cryptography, but steganography, but you are using an innocent looking sheet of paper and paint the map in invisible ink which will be visible if heated. The idea is already known in the time of the old Greeks. **[Grille](https://en.wikipedia.org/wiki/Grille_%28cryptography%29)** Use a Fleißner Grill. Draw the map, divide it in equal parts divisible by four and create a template where one fourth of entries are open. Look at the windows, enumerate the parts on the back, rotate the grille and continue. In this case the map must not have shared lines or features on their borders because then it is a jigsaw puzzle which can be solved.. [Answer] Excellent question. I don't know if it has ever been done. ## Substitution and Transposition First, re-arranging map elements, such as a mountain-replaced-by-a-body-of-water. But this is recognizable to someone familiar with your region. Next, re-assembly of the mapped region by squares of, say 500m x 500m, so that there is a distortion that only your readers can understand how to re-assemble it. Smooth out the features so that they blend together and you have a map of an un-recognizable region with features that are not familiar to anyone from 'round here. Your readers then take up the scissors and re-assemble and re-substitute. Feel free to throw in classic cryptography of the names of features or strategic positions after that. [Answer] One idea which can be combined with the others is to have a stack of decoys. Following the wrong one can be expensive or dangerous, if it includes things like safe reef passages and mountain passes. You have to know which parts of which sheets are right, as well as how to fold/mask/layer them properly. The cost of brute-forcing the key could then be higher than the value of the map. Some specific details might be practically coded as plain text, which is then encrypted in a conventional manner. For example, a shoreline can be covered with numbered points, and the safe way through the rocks/reefs is encoded as a list of waypoints in a separate document. [Answer] [Visual Cryptography](https://en.wikipedia.org/wiki/Visual_cryptography) provides a very nice approach:  The advantage is that if done right, each share has exactly zero information. Suppose that you convert the map into grayscale "pixels". You take a transparent sheet and for each pixel, fill half of the pixel at a random orientation. This is the key. Now you take another transparent sheet, put it on top of the key sheet, and start drawing the map by filling exactly half of each pixel again, but at such an orientation that combined with the underlying key it will either result in a fully black pixel, a half-black pixel, or anywhere inbetween. Very simple, completely secure (zero information in each share separately), and does not require a computer to create. (though admittedly transparent sheets might be difficult to come by in those times) [Answer] How about drawing the maps on the glass of a set of lamps. When you want to see the map, you can set the lamps up at a certain distance and angle to a screen (this would be the key). You then setup a screen of some sort (like the wall of a tent, or other flat, lightly colored surface) When you light all the lamps, the map is projected onto the screen. If you don't want the maps captured, smash them. It would look like this, except the pictures would be parts of a map, and overlapping. Also, you could have a more complicated shade or blown glass cover for the lamp to distort or mask things for more secrecy.  [Answer] ## Use stack of transparent papers  Each paper consists of patches of real and fake parts of a map drawn on them (with solid background), but it is mostly transparent. When stack in the correct order, all fake pieces are hidden under the real ones, revealing the true map. Every paper is numbered from 1 to N, giving N! different arrangements. The decryption key is a sequence of numbers in which they need to be stacked. Papers are randomly shuffled before storing the map. This map is easy to decrypt and read and decrypting doesn't require any additional items. In addition the map can be split between multiple parties. Also pieces that contain only fake patches can be added to increase the difficulty. Edit: In addition every piece can be stack in obverse or reverse giving you total of N!\*2^N possibilities [Answer] Use a one-time pad with XOR. **To encrypt** 1) Draw your map as a black and white grid of squares (bitmap) made up of filled and empty squares (plaintext) ``` _________ |_|_|_|_| |_|X|X|X| |_|X|_|_| |_|X|_|_| ``` obviously you can make this as big as you want. 2) Draw another bitmap with squares filled in randomly (key) ``` _________ |X|_|X|X| |X|_|X|_| |_|X|_|X| |_|X|X|_| ``` 3) Draw your encrypted map with the following rules: For each square compare the contents of 1) and 2) and colour in only the squares that are different (black in one, but not the other) ``` _________ |X|_|X|X| |X|X|_|X| |_|_|_|X| |_|_|X|_| ``` --- **To decrypt:** Take 3) and 2) For each square compare the contents of and colour in only the squares that are different (black in one, but not the other) Voila, you get 1) back. ``` _________ |X|_|X|X| |X|X|_|X| |_|_|_|X| |_|_|X|_| _________ |X|_|X|X| |X|_|X|_| |_|X|_|X| |_|X|X|_| ``` => original ``` _________ |_|_|_|_| |_|X|X|X| |_|X|_|_| |_|X|_|_| ``` Provided you filled in 2) randomly then there is no way of breaking this encryption unless you have the key. Also you should only use 2) once and not for a set of maps. [Answer] Similar to what Mnementh suggested. Start with a large piece of high quality leather. Leave large top and bottom margins and draw the map in between. Full width but only the middle part vertically. Now divide the map into vertical strips of width suitable for a belt with a marker. From these strips mark a belt length portion that covers the map containing but has a different top and bottom margins, start and end points for each strip. Belt holes and buckles should also go to the unmarked part. Cut off the strips, fill the unmarked parts with fake map lines, and turn the strips into belts. The belt decoration on the other side should tell with some code the strip ordering and the top margins used. Anyone who knows the same code of markings to order and margin can reassemble the map. Presuming that they use same measures for the margins... Each belt can be given to different person and aged to different degree. [Answer] I'm most familiar with the encryption of numbers, so I came at this from a numbers angle. Maps can be numbers, most usually in a grid. These numbers can either represent geographical features, topography, or something else entirely. Features grid visually represented (screenshot of Advance Wars on GBA):  Topography: [](https://i.stack.imgur.com/7WPzB.png) Now, since we're using numbers, we can use classic encryption methods. You'd have your original map, and you'd have a key, a grid of random numbers. You could then add/etc. the respective numbers on both grids to form the encrypted map. As long as the recipient had the key, they could reverse calculate the original map, and it would be impossible for anybody without a key to decrypt it, as there could feasibly be a key that would generate any possible map. [Answer] An idea is having longer stripes of paper. Lets say you have six of these stripes (ABCDEF). Some of them you can now lay horizontal, some vertical, lets say: ``` AAA BBB CCC DEF DEF DEF ``` Now you lay the stripes over each other in a pattern, so that some parts are hidden by others: ``` AEA DBF CEF ``` On the parts that are hidden in the final layout paint some fake map to distract people. [Answer] Well it seems to me that any kind of direct-placement of symbols on a page wouldn't work, simply because it doesn't matter what the symbols are -- anyone familiar with the area could infer meaning from them, and deduce an "unusual" one to be more important. Instead, some means of scrambling the actual data seems in order. That's rather challenging to do with a single, homogeneous page, as there is no easy way to un-scramble paper, except with cutting and rearranging, as @Mikey suggests. I'd imagine some kind of tool or "key" used to encode and decode the map. Such as a specially-shaped glass lens. Place it on top of the map, and it de-encrypts it. Or blue-glass filter, and multi-color paper. Hard to see the real data without it. Or a chemical added to it, which only reacts with another chemical. [Answer] The requirement that the map can be used while on a journey, presumably under Medieval conditions, is a tough condition. I can think of all sorts of ways of encrypting a map using technology available in the Middle Ages, but most of the ideas I come up with would require considerable time to decrypt, tools that might not be so convenient to lug around, etc. But here are two ideas that I can suggest: 1. Cut the map into pieces, with each piece being too small to be of practical value. Write some code number of symbols on each piece that can be used to put them back together correctly. Note the symbol must be in code: obviously if the pieces are simply labeled with grid co-ordinates, anyone could quickly figure this out and put them together. But there are any number of routine cyphers available to encrypt the grid co-ordinates. Combine this with encrypting any text on the map, so that an unauthorized person can't use place names as clues to figuring out the proper arrangement. Deliberately mis-align things that cross the borders between sections slightly. You don't want someone to be able to re-arrange the pieces by lining up roads and rivers, or you just turn the cypher into a jigsaw puzzle. So if, say, a road crosses from tile A4 to tile E6, move the road just slightly to the north on the edge of A4 and slightly to the south on the edge of B6 so it doesn't line up. 2. Use conventional map symbols, but use them randomly for the wrong things. Like on one part of the map a blue line may be a river like we would expect, but elsewhere it is a road, and yet somewhere else it is a mountain range. Coded text on the map tells which it is in each case. The text is encrypted by conventional means. So if I see what looks like a mountain range, and it's labeled "Fwghthrnbr", and I decrypt this and it turns out to mean "Rhine River", then I know this mountain range really represents a river. Hmm, if we use a system to encrypt the text that doesn't look like code but like plausible names, like we encrypt "Rhine River" as "Harold's Mountains", then to someone trying to read the map, it might look like an ordinary map, and he just can't figure out where this place is. If he doesn't realize it's in code, he won't try to crack the code. It would be easy enough to have some substitution cypher that treats common terrain names, like "River", "City", "Bridge", etc, as units that are transformed into each other according to some set and reversible rules. Like arrange them in a list and then go up or down so many slots in the list based on the position of the word on the map or other words around it. [Answer] Usability may depend on intentions. Assume you want to transfer a map from A to B once, with the risk of being intercepted. Shave the head of a messenger. Tattoo the map on his skalp. Wait for his hair to grow. Send the messenger (with a fake map for distraction). At the destination shave hime again. [Answer] Draw a normal and usable map but include some extra points (like trees with n branches or letters with a special shape..) in it. To decipher the secrets one would have to connect the extra points.. The crossing of two or more connectors are the hidden places.. [Answer] ## Don't make a map, make directions Think about what a map really is. A map is a visual display of local geography. It shows rivers, hills, roads and towns. The biggest reason a map is used is to figure out directions to get to a certain place. Therefore, instead of encrypting the map, cut out the middleman and just give directions. ## Make the directions harder to follow for those that must not know Instead of using official names for villages, use codewords that include minor events from villages. Refer to villages not by the village name, but by the name of a local dignitary. Most people don't know the name of the dignitaries a village over. Hell, most people don't even know the names for their own village dignitaries. [Answer] How about having a **Mirror Key** for your encoded map? You place the mirror at a certain location on the map with a certain orientation, then look at it from a certain point and the map will come into focus. **Notes:** * The mirror key doesn't need to be a perfect mirror, but instead just reflective enough to make out the image. Polished metal would work and would be consistent with medieval times * As you are drawing your encoded map you need to replicate the same setup as when you'll read it later, and then draw it based on the reflected image you want (I'm sure that will take a LOT of patience and practice). * You can also have "dark" places that won't show up in your reflected image. This will let you add in features to the map that don't belong. * You can vary several things to make it difficult to read the map even if someone finds the mirror and the map together: + Where you put the mirror in relation to the map + What side of the mirror is up + What angle to hold the mirror at + Where you look at the image from + How the map is folded * The mirror will take some experimentation to get right. For example, you may find that some setups won't work because the places you'll need to draw will overlap. Probably the easiest would be to cut flat pieces and have them at different planned angles to avoid this. However, curved pieces would add an extra layer of distortion (and complexity!)  [Answer] Encrypt the text-based instructions necessary for creating the map for example, take a chess game and imagine the board as a map - most commonly, the board arrangement is determined by walking through how the pieces got there rather than giving each piece a coordinate so for example, you could have instructions to place a city in the dead center, then a mountain range from east to west just north of the city, an enemy city a quarter of the map away to the north-east on the other side of the mountain range, and then an equal amount away but to the north-west have a hidden cave with the treasure, that will be visible only by the last light of Durin's Day, etc. [Answer]  [Up is down](https://www.youtube.com/watch?v=sNj8mJq65i4). (I can't make comments yet) --- \*sigh\* Ok, this is a map featured in the third Pirates of the Caribbean movie. It consist of several [Annulus](https://en.wikipedia.org/wiki/Annulus_%28mathematics%29) of different sizes, with a circle in the center of them all. I think this could be done with thin wood by attaching the circle and the outer annulus to other, more stable surface (like another piece of thin wood, either circular or square). Or, maybe it doesn't have to be attached at all; by leaving the pieces separated (and maybe split in several parts) they can be carried easily and add other level of difficulty to this. It could also be done in paper, though. Since the pieces can be rotated, the key is the relative position of all the pieces. If the annulus are split in several parts, its pieces have many ways to be put together as long as there are no recognizable "outlines" (as stated below), but that could be solved by adding fake ones. Each piece could have some sort of identifier, like signs, letters or numbers (don't have to be sequential, it may be "1", "-8", "Pi" for example), so one can remember their relative order. All locations don't have to be real, only the relevant one. The rest can be fake to make it harder to solve the puzzle. Annotations could be made like in the film (between one annulus and other, as seen in the pic), or inside of them. You could use one key for the map in question, and other key for the annotations. The downside of this is that it has to be a map of either many outlined parts (as is the case of the movie with islands), or a map of a zone with no recognizable outlines (e.g. a river). If it contains a river, the solution would be make only one part of the river "real" (the most relevant) and then complete it with fake splits, if possible in other part of the map but that, when using a certain key ("position") the fake river matches with the real (i.e. a "collision" in the "output"). [Answer] As an extension to Andrew's answer, quickly generating pseudorandom binary strings for the one time pad by hand can done in the following way: * Take a number and transform it into binary. * Add a 0 to the end of the bit string. * Remove the first bit from the string. * XOR this string with the previous string. * This is your random string. * Repeat. This is based on the [Xorshift](https://en.wikipedia.org/wiki/Xorshift) algorithm. This algorithm will generate $2^n$ random numbers for a seed of length n. It is not secure, but it eliminates the need to share a large amount of random numbers. An Example: 11011 (The start number) - First Number - 27. 110110 (Add a zero.) 10110 (Remove the first bit.) 01101 (XOR with previous result) - Second number - 21. ... A simple implementation in Python: ``` def random(seed): seed ^= seed << 1 yield seed ``` ]

[Question] [ I understand that it's long been a tradition in American fictional works, especially movies and TV, to use a '555' phone code for any numbers that needed to be displayed on-screen, as that prefix doesn't exist, and so there was no risk of the writers unwittingly using a real number. As a writer of stories, my question is: Are there any similar non-existent or otherwise reserved top-level domains that I could use in a fictional context to avoid inadvertently publishing an in-use—or a 'likely-to-come-into-use'—domain? I'm aware that TLDs are being created a lot more quickly than they were, but I didn't know if there were any specifically set aside. As additional info, my current project is an alternate history story set in a modern-day Roman state, so I'd ideally be looking for a TLD I could crowbar into representing that in some way. I did consider `.spqr` as a sort of equivalent to `.gov`, though that's maybe a little heavy-handed setting-wise (but of course that's for me to figure out...). I've also checked [this list at ICANN](https://data.iana.org/TLD/tlds-alpha-by-domain.txt), and I can't see, for example, `.spqr` or `.rom`. I'd be cautious about using them if they're potentially available for future registration. --- EDIT 23/Jan/17: Wow. I'd like to thank everyone who's taken the time to reply to this. I really do appreciate it, and there have been some great suggestions. I think, on balance, probably the easiest way to go is, as some have said, to simply come up with a new format for addresses, on the assumption that in my alternate history many things will be different, some subtly, some less so - so this might as well be one of them. Even so, there have been some great ideas, and some interesting info provided. I'm still going through some of the comments as I have chance - please forgive me if I don't answer them all! Again, thanks for taking time to offer these suggestions. [Answer] ### Register a real domain You could think about registering a **real** domain (with a name relevant to your novel) and then: * Adding some real content that either is an optional part of the story or * Adding content that promotes your work. The following links provide complete instructions on how to register a domain name. * [How to Register Your Own Domain Name](https://www.thesitewizard.com/archive/registerdomain.shtml) * [How to Register a Domain Name](http://www.wikihow.com/Register-a-Domain-Name) --- ### Register a new Top Level Domain Several comments have suggested creating a new TLD (Top Level Domain). This is **not** recommended because: * It's nowhere near as easy as registering a second or third level domain and comes with significant extra responsibilities. > > The application for a new gTLD is a much more complex process. An applicant for a new gTLD is, in fact, applying to create and operate a registry business supporting the Internet's domain name system. This involves a number of significant responsibilities, as the operator of a new gTLD is running a piece of visible Internet infrastructure. > > > * It is very expensive. > > The evaluation fee is USD 185,000. Applicants will be required to pay a USD 5,000 deposit fee per requested application slot when registering. The deposit will be credited against the evaluation fee. > > > ... > > > Once an application has successfully passed all the evaluation steps, the applicant is required to sign a New gTLD Agreement (also called Registry Agreement) with ICANN. Under the agreement, there are two fees: (a) a fixed fee of USD 6,250 per calendar quarter; (b) and a transaction fee of USD 0.25. The latter does not apply until and unless more than 50,000 transactions have occurred in the TLD during any calendar quarter or any four calendar quarter period. Please refer to section 6.1 of the New gTLD Agreement in the Applicant Guidebook. > > > Source [Frequently Asked Questions](https://newgtlds.icann.org/en/applicants/global-support/faqs/faqs-en) [Answer] Several people have suggested the possibility of using real-life reserved domain names. (For those curious, I have a summary of [names and networks reserved for examples and documentation](https://michael.kjorling.se/computers/internet-reservations/examples-and-documentation) on my personal web site.) Some people have even suggested using real-world domain names that are somehow undesirable, but still valid. Yet others have suggested to register a domain name of your own, such that you are able to control its content. I'm going to go out on a limb and suggest that **there is a way to make up valid-looking domain names that actually *will not* exist.** **That's because the two-letter top level domains are ISO 3166-1 alpha-2 country or territory codes.** ([ruakh](https://worldbuilding.stackexchange.com/users/2183/ruakh) pointed out in a comment that there exist exceptions to this rule. See below.) Wikipedia has a handy table of [assignment status](https://en.wikipedia.org/wiki/ISO_3166-1_alpha-2#Decoding_table) of all such code combinations. There are four ranges that are "free for assignment at the disposal of users" and thus, barring a major rework of the ISO standard, cannot possibly become valid top-level domains. Those are `AA` (just that one), `QM` through `QZ`, `XA` through `XZ` and `ZZ` (just that one). The same Wikipedia article also has a short list of examples [how some of these are currently being used](https://en.wikipedia.org/wiki/ISO_3166-1_alpha-2#User-assigned_code_elements). There are also a large number of codes [reserved but not free for assignment](https://en.wikipedia.org/wiki/ISO_3166-1_alpha-2#Reserved_code_elements) for various reasons and varying lengths of time. **Basically, if you compose a domain name like you normally would on the Internet,** * but give it a top-level domain out of the ISO 3166-1 alpha-2 "free for assignment at the disposal of users" range, then you can be *all but certain* that it will not clash with any real-world Internet domain name now or in the future. * but use any of the other ISO 3166-1 alpha-2 reserved combinations for a TLD, then you have to check to make sure that you aren't causing a potential name conflict (for example, `EU` is "exceptionally reserved", and is actually available as a top-level domain), but for the most part you *should* be okay. So it's perfectly possible for your character to have an email address like `[[email protected]](/cdn-cgi/l/email-protection)` and you can be as certain as one can reasonably be that nobody will be registering the domain name `momandpopwebmail.qw` for use on the actual Internet. (Maybe "QW" means "quickweb" in your world?) ## *Always* ISO 3166-1 alpha-2? As was pointed out by ruakh, citing `.uk` as an example, there are a small number of country-code top-level domains that do not match the country's ISO 3166-1 alpha-2 country code, which in this case is `GB`. The criteria for eligibility for a two-letter ccTLD are laid out [by the Internet Assigned Numbers Authority (IANA)](https://www.iana.org/help/eligible-tlds). There are a few other exceptional cases allowed for, but the main exception is for ccTLDs that do not match the country's alpha-2 code, but were originally approved before 2000 under an exceptional delegation in ISO 3166 and still maintain that status: > > * Grandfathered prior to 2000. ICANN codified the rules under which future exceptionally reserved delegations may be considered in 2000 in Resolution 00.74. Certain domains were delegated on the basis of being “exceptionally reserved” by the ISO 3166 Maintenance Agency prior to this date. These domains were “.UK”, “.AC”, “.GG” and “.JE”. Of these, “.GG” and “.JE” are now listed in the ISO 3166-1 standard and therefore qualify normally. The remaining two domains that are grandfathered under their original eligibility are “.UK” and “.AC”. > > > It's worth noting in relation to ruakh's example of the United Kingdom that the Internet Corporation for Assigned Names and Numbers (ICANN) lists [`.gb` as "unassigned, reserved" and "originally meant to replace `.uk`"](https://icannwiki.com/CcTLD#Current_ccTLDs). We also note that Wikipedia's summary table lists both `AC` and `UK` as "exceptionally reserved". Because the rule quoted above is about the eligibility of ccTLDs that were established before the current rules for ccTLD eligibility took effect in year 2000, barring an IANA rule change, *no new ccTLDs can be assigned under the grandfathering criteria.* While not exactly an ISO standard, these rules do on the Internet have status similar to that of an ISO standard. Since none of the "free for assignment at the disposal of users" ISO 3166-1 alpha-2 codes fall under the grandfathering rule, and no other eligibility criteria appear to apply, **we can still safely use those ranges confident in our assessment that they will not be assigned as top-level domains.** # What about two-ASCII-letter TLDs not covered by ISO 3166-1 alpha-2? This is covered by [Internet Corporation for Assigned Names and Numbers (ICANN) Resolution 00.74](https://features.icann.org/2000-09-25-delegation-cctlds), which states that (my emphasis): > > It is therefore RESOLVED [00.74] that the IANA staff is advised that **alpha-2 codes not on the ISO 3166-1 list are delegable as ccTLDs only** in cases where the ISO 3166 Maintenance Agency, on its exceptional reservation list, **has issued a reservation of the code** that covers any application of ISO 3166-1 that needs a coded representation in the name of the country, territory, or area involved; > > > The "advised" is a bit of a red herring here; it means "we are telling you that", not "we are suggesting that". The operative part specifies that "alpha-2 codes not on the ISO 3166-1 list" can be assigned as ccTLDs *only* in the case that said code has a status of "exceptional reservation". As a consequence, the set of TLDs described by "alpha-2 codes" (two English alphabet characters) is restricted to the meaning that those character combinations have in ISO 3166-1 alpha-2. # But... but... what about in the future? Sure, things can change. But at this level, things change very slowly. Given how many different entities likely use the "free for assignment at the disposal of users" ISO 3166-1 alpha-2 ranges [for their internal use](https://en.wikipedia.org/wiki/ISO_3166-1_alpha-2#User-assigned_code_elements), were the relevant ISO committee to start to assign those codes for other uses, all hell would break loose. If these codes are ever to be assigned to any other use, there would likely be a *decades-long* transitionary period preceding it. Compare the current [transitional reservations](https://en.wikipedia.org/wiki/ISO_3166-1_alpha-2#Transitional_reservations) which in several cases stretch out to the 2050s, still a good 30-40 years into the future. Also note that a good half or so of the alpha-2 codes are as of yet *unassigned*. Should [a new country appear](https://politics.stackexchange.com/q/25538/6642 "What are the steps to become an independent country once independence has been declared?") tomorrow that is [sufficiently recognized](https://politics.stackexchange.com/q/194/6642 "What exactly formally constitutes recognition of a country?") to receive its own ISO 3166-1 alpha-2 code, it is likely that an appropriate two-letter code could be selected without needing to do anything with the ranges that are specifically available for users' own use. We also note that [the Frequently Asked Questions for the gTLD application process as published by the ICANN](https://newgtlds.icann.org/en/applicants/global-support/faqs/faqs-en) specifically states that (my emphasis) > > 2.12 Can a New gTLD name be 2 letters? > > > Applied-for gTLD strings in ASCII must be composed of three or more visually distinct characters. **Two-character ASCII strings are not permitted, to avoid conflicting with current and future country-codes** based on the ISO 3166-1 standard. > > > On the whole, I wouldn't worry about the risk of collions between future assigned TLDs and the "free for assignment at the disposal of users" ranges in ISO 3166-1 alpha-2. If it ever happens, your story might even become a bit of international relationships history. # TL;DR: * Use a two-letter top-level domain of `AA`, `QM` through `QZ`, `XA` through `XZ` or `ZZ`. [Answer] As mentioned by @journeyman-geek, you might consider giving your world an alternative name resolution system which avoids collision by not following the format of domain names as seen in our own DNS system. This is easy to imagine as the defining features of modern DNS names (and, by extension, URLs) are largely historical accident. For example, many email addresses in the *Ender's Game* series look like `hgraff%[[email protected]](/cdn-cgi/l/email-protection)`. A `%` sign in the email address was used by [various network gateways](http://foldoc.org/pub/misc/arpa-hopping) such as the CSNET relay, something which was common at the time the first Ender books were written but is unheard of today. One such possible scheme could be to reverse the hierarchical order and use colons instead of periods, yielding a format such as `spqr:senate:marcus·tullius·cicero`. (Note also the interpunct, an obscure character in the English alphabet but one which I assume was likely included in basic RSCII and allowed in their DNS names.) [Answer] Nothing that would really work - as per bob's excellent comment, there's a list of reserved, example TLDs, none of which are suitable and the new gTLDs are pretty broad. There's nothing stopping a organisation with a justification and enough money from registring any new gTLD. Its worth considering the rich and varied tradition of *making things up* when talking about computers in media, from interfaces to websites. As such the 'clever' way would be to introduce some slight, subtle inconsistancy. 555 was picked so it wouldn't route to any phone number You could simply pick a branch of the multiverse where things went differently, colons instead of dots, or even having your network as one large set of directories. So the office of the imperitor general of the imperial sanitation department might be at spqr/sanitation/org/official/imperitor. This would break in any modern web browser and would be consistant. Or just gloss it over and tell, don't show. [Answer] There is the tTLD (test top-level domain) class of domains, like `.test` (see <https://en.wikipedia.org/wiki/.test> or [RFC 6761 from February 2013, section 6.2](https://www.rfc-editor.org/rfc/rfc6761#section-6.2)), the same in various scripts and common languages for that script (<https://en.wikipedia.org/wiki/Top-level_domain#IDN_test_domains>). [RFC 2606 from June 1999, section 2](https://www.rfc-editor.org/rfc/rfc2606#section-2) also mentions `.test` and additionally: * `.example` * `.invalid` * `.localhost` with the following explanation: > > > ``` > ".test" is recommended for use in testing of current or new DNS > > ``` > > ``` related code. ``` > > > ``` > ".example" is recommended for use in documentation or as examples. > > ``` > > > > > ``` > ".invalid" is intended for use in online construction of domain > > ``` > > ``` names that are sure to be invalid and which it is obvious at a glance are invalid. ``` > > > ``` > The ".localhost" TLD has traditionally been statically defined in > > ``` > > ``` host DNS implementations as having an A record pointing to the loop back IP address and is reserved for such use. Any other use would conflict with widely deployed code which assumes this use. ``` [Answer] # If your world allows, your world's Internet doesn't work the same. If you create your Internet to use underscores, a certain character, or a character you invented instead of a period, then you can have whatever address (if your new Internet uses addresses) you want. Or you could do away with top and sub domains all together. For example you could have John Doe's email address be: ``` John-doe@email ``` And have the search engine address be: ``` websearch ``` This is pretty future proof, because top and sub domains aren't going anywhere. Those were some ideas, you could get creative with your new Internet. [Answer] As part of the general idea of making something that would not be a legal TLD (as o.m. notes), you could have a character not found in ASCII as part of the TLD. The [development](https://en.wikipedia.org/wiki/History_of_the_Latin_alphabet#Historical_development) turned out a little different in your universe. This could work especially well if the alternate history skipped something that was responsible for one of our modern letters, so *of course* that would be different. Using a real (historical) letter has the advantage of being able to type and print it: (Þ, þ) is one of my favorites. Or maybe they kept some that look more like the Greek progenitors (Γ instead of C) or G is still a C with diacritical mark. I think it would be interesting if one such change were present in names and such; not so much as to baffle the reader, but just one difference to give it a unique character [pun intended]. With internationalized domain names now, *mixing* scripts from different languages (like using Γ for C but otherwise Latin characters) is unlikely to match any future domain name, which will be in one language or the other but not mix languages in the same word. If the book is self-published and you’re providing print-ready PDF, you could make your own unique character. But it’s quite hard to invent something suitable as a letter that’s not already real (and hopefully in Unicode). Much of the URI syntax is “just the way it turned out” and it could easily have been different. I recall reading that Tim Berners-Lee considers the current system inconsistent with the hostname backwards from the path, and use of different separators is unnecessary. So `www.example.com/site/page#fragment` should really be `com.example.www.site.page.fragment`. Point is, in an alternate history you will **expect** the syntax to be different in detail, even if they hit upon the same general idea of a uniform resource locator as a hiarchy that extends a machine’s directory structure. You might use a different (or different *looking*) character as the separator, such as a tiny superscript `^` or a vertical bar that spans the whole ascender through decender height of the character cell. [Answer] You can use the system most countries that are not the USA use. Combining the TLD for the purpose of the website with the country's TLD For example the website for the praetorian guard would be: `www.praetorian-guard.gov.rom` or `www.praetorian-guard.gov.spqr` while a normal website would be along the lines of `www.pizza.com.rom` or `www.pizza.com.spqr`. That way, even if the TLD `.spqr` or `.rom` are registered as a gTLD, the websites would not exist because such format is only used for regular TLDs. And it's not like a new country will just appear and claim `.spqr` or `.rom` anytime soon, if ever. [Answer] How about something that would not be a valid domain name, but looks roughly like one? .sen\_rome .r Reserved ones are things like .test or .invalid, they stand out in a story. [Answer] FYI Rome's actual institutional website domains are: * `www.comune.roma.it` (literally"common".rome.it) * `www.cittametropolitanaroma.gov.it` (lit. "metropolitan city of rome".gov.it) I live there & I would incredibly love to see the '.spqr' in such a story. Anyways, I don't believe that domain name will ever be added (never say never: angry spanish people got `.cat` domain). Anyways consider this: if the Roman Empire survived 2300 years they would have developed other ways to describe domains. But, because you are the author and people (or nerds?) expect a normal-looking domain name you could just flip the entire name like java packages or similar dot-separated syntax. There would not be an international standard as the emperor ands senators would have it very roman-centric, i think maybe a sort of directory-like nomenclature for websites, where every website would be given an unique domain name by the Pontifex (or his office). There would be an hyper textum translationis protocollum using that to fetch resources for users. For example one of the few approved search engines, the Google Indagator, is reachable here: `http://spqr.indagator.google`. Here is Ceasar's memorial website: `http://spqr.historia.caesar`. As romans sought to integrate other people in the empire they would eventually add something like: `http://spqr.barbari.carthago.voluptuaria` for websites about external countries (this specific one to have a family trip to the ruins of a famous city in Tunisia). [Answer] You could use a single-letter second-level domain in .com, .net, or .org, like y.com, or 1.org. There is more info on which TLDs won’t accept these in the Wikipedia article “[Single-letter second-level domain](https://en.wikipedia.org/wiki/Single-letter_second-level_domain)”. Another option would be to make up your own addressing scheme like: ``` <info-link#info-provider:some-company:blah> ``` [Answer] a.com, b.com, c.com, etc. > > In 1993, the Internet Assigned Numbers Authority (IANA) explicitly reserved all single-letter and single-digit second-level domain names in the top-level domains com, net, and org > > > Some were reserved before '93 and do actually have sites (i.net, q.com, q.net, x.com, x.org, z.com, a.co, g.co, t.co, t.me, w.org), but everything else is off limits. However... > > In December 2005, ICANN considered auctioning these domains > > > So maybe these domains will be available someday. But it's been 11 years, so I wouldn't bite my nails about it. Source: [Single-letter second-level domain](https://en.wikipedia.org/wiki/Single-letter_second-level_domain) [Answer] Perhaps something quite different, like sort-of an X.400 address with different labels: nun=incudibus,dpca=acme,dap=com [Answer] ## There are reserved IP addresses For example, 127.0.0.1 routes back to your own computer, while 192.168.XXX.XXX addresses are reserved for internal use in private networks, as are the 10.XXX.XXX.XXX and 172.16.XXX.XXX blocks. You can safely use them as fictional addresses knowing that no-one on the internet has these addresses. There are also some IP blocks reserved for documentation, namely 192.0.2.XXX, 198.51.100.XXX and 203.0.133.XXX. IPv6 has the block 2001.bd8.XXXX.XXXX.XXXX.XXXX.XXXX.XXXX reserved for documentation, while fcXX.XXXX.XXXX.XXXX.XXXX.XXXX.XXXX.XXXX is for use in private networks. Unfortunately they're not quite as punchy as domain names, although you can actually connect to IP addresses through your browser. <https://en.wikipedia.org/wiki/Reserved_IP_addresses> <https://michael.kjorling.se/computers/internet-reservations/examples-and-documentation> [Answer] I don't believe there are any reserved names for authors. I know that Microsoft reserved some fictitious names themselves so perhaps that is a good example of what others do. <https://blogs.msdn.microsoft.com/oldnewthing/20061013-05/?p=29393> [Answer] I stumbled upon this in 2022 and it occured to me that the trends of cctlds have changed a bit since 2017. For example, there is now .scot, .wales, .quebec, and .cat. So for a theoretical a modern day Rome a cctld of .spqr wouldn't be that odd after all. <https://en.wikipedia.org/wiki/Geographic_top-level_domain> ]

[Question] [ I am looking at different ways to destroy a planet - because a society within my setting wants to destroy a planet. I am assuming the planet is of a similar size and composition to the Earth just to keep things simple. I am starting at boiling the atmosphere to the point where it turns Earth into a dead barren rock with no vegetation, no oceans and no air left. This is as tame as I want my destruction (there's still a giant dead rock left, and I want to wreak more havoc than this!). I am also looking into lasers powerful enough to obliterate a planet into dust, AKA the Death Star approach. At the most I am not sure if the energy required to achieve this makes this a feasible option. (Yeah, I know, I am concerned if *this* is feasible and then I go onto consider something else like:) Ive been considering something that destabilizes the very structure of a planet, affecting everything from plate tectonics to the planets own gravitational pull on itself and causing a chain reaction which results in the planet flying apart. But I am not sure if I can back this up with any kind of science. I have also considered launching another, large enough, rock in space at a planet to smash it into smithereens. I have also looked into detonating the nearby star to take out the planet and the entire system. My problem is that I don't know which one of these (or any other crazy ideas that I have) forms of global destruction are the easiest to achieve. So my question is: **What would be the most effective or efficient way to destroy an entire planet?** I dont just want to destroy all life on the surface, I want to reduce the entire planet to rubble so that very little remains (I guess an asteroid field/belt being left behind is destruction enough, but bonus points if you can cause more destruction!). I also want to do this in a relatively short time frame. Say, less than a day. I plan to model my fictional society on the answers given here. [Answer] **Countering the gravitational binding energy of a (earth-sized) planet takes [roughly 2.4E32 joules](http://www.stardestroyer.net/Empire/Tech/Beam/DeathStar.html).** That's enough to make it come apart, but it would be a slow process; if you want it to blow apart you'll need to add *more* than that. It doesn't matter too much how you deliver that energy, just that it gets to that total somehow. **So what does that mean in practical terms? Well, 2.4E32J (or 240 million yottajoules) is roughly equivalent to:** The total energy output of the Sun in eight days. The energy delivered by a rock the size of Mercury and travelling at the same speed as Earth but in the opposite direction. A large asteroid (100km across) travelling at very, very, *very* close to the speed of light. One quadrillion bombs the size of the Tsar Bomba (the largest nuke ever built). The energy released by 1.3 trillion tonnes of antimatter hitting the same amount of regular matter. **Essentially, blowing up a planet is really, *really* hard.** If you're staying mostly within the realms of normal physics, the most promising option is probably to hit it with another planet. If you can accelerate things effectively to light-speed, then you can use a smaller rock (for an asteroid-sized rock, the difference between 'fast enough' and *actual* light speed is too small to be worth calculating.) Alternatively, you can use an ungodly amount of explosives - antimatter or conventional, the energy requirements are high enough that it more-or-less stops mattering. Lasers are out - you'd need an energy output roughly 10 times that of the sun, and there's simply no way to build a laser that powerful without it destroying itself the moment you switch it on. Destablising the planet, unfortunately, is going to require some form of sci-fi gadget that doesn't follow the currently understood laws of physics. (Or, at the very least, one you're pumping 2.4E32 joules into to make it work. And, as noted above, that's a ***lot*** of energy...) Of course, if you've got the resources to pull any of these off there's another simple option: **knock the planet out of orbit so it falls into the sun.** [Answer] Just put ***humans*** on that rock (with or without space suits). This animal species was observed over the course of history to destroy mostly anything it encountered in its path, you could extrapolate to find it could be, at least *theoretically*, capable of destroying a whole planet. sorry, couldn't help it :) but it might not be too off-topic, consider a human posted this question and others are thinking about it... [Answer] If you want to rip a whole planet apart then it's very hard, the amount of energy required is immense. The simplest way would be to use tidal forces. Get something like a neutron star, black hole, or gas giant and bring that in close enough to the planet to be destroyed (inside the Roche Limit) so that tidal forces rip it apart. Theoretically some sort of sci-fi weapon "black hole generator" could do the same job, or just drop the black hole into the planet and let it eat it. That would leave a black hole rather than rubble though. Consider how much energy is involved in moving something like a gas giant or neutron star close to our planet and that should help you picture just how big what you are attempting here is. [Answer] The normal physics approach got handled well in the other answers. So let me propose an alternative option: Bend the physical laws as we know it. There are actually theories that wonder if the laws of physics and the constants used in there were always the way we experience them today. Some far future high tech weapon (or an accident involving a fridge, a smartphone and a cup of tea) might change one of a natural constant in a limited space time range. For example if you increase the gravitational constant on the planet far enough it would collapse to a small star, neutron star or even a tiny black hole. If the gravitational constant returns to normal, the remains might even explode. For more information about this approach I'd consider a follow up question on <https://physics.stackexchange.com/> [Answer] **How many energy would you need to blast the earth?** I'm sorry to provide this image in german language, but I think you get the point and you are able to translate the catchwords. You could use this [translation](http://www.dict.cc/) site. This graph shows how much energy specific events unleash. The Asteroidimpact 65M years ago had circa 1000 times the power of all nuclear weapons existing and only scratched the hull of our small planet (200km crater). So you might understand which massive power you need to blow a planet up. This is not possible from our technical capabilities of today. Maybe, if you collect all explosive material mankind could gather at a single point in a little distance to the planets survace, you could change the direction in that way, that the planet "fall" into the sun within some thousands or millions of years. Just why,...  [Here](https://physics.stackexchange.com/questions/56633/how-much-energy-would-it-take-to-blow-up-the-earth) is a post about how much energy is needet to blow the earth. > > 2.24 × 10^32J or 5.34 x 10^16 Mega ton > > > 22 400 000 000 000 000 000 000 000 000 000 Joule (!) > > > One nuclear warhead has an average power of 1 mega ton. 5.34 x 10^16 atomic bombs needet, 17.000 existing. Thats nothing. So now you might be able to picture the energy you need. In the End I would say, at this point this is just impossible. EDIT: (Moved in quotebox due its a unnecessary additional, I missunderstand one point which makes this obsolete) > > I think this question is far to broad to give a specific answer, but I'll try. > > > The way you can destroy a planet depends on many factors and I'll go over some of them. > While doing this I sometimes take comparisons like "small vs big". Doing this I always assume that both (small and big, far and close,...) have everything in common, except the state I'm talking about. > > > **Size** > > > A large planet is more resistant against impact and explosions. > Also, a large planet is not pushed out of it's orbit with ease. > > > **Material** > > > Do not underestimate this point(!) > How would you try to destroy a gas giant like Jupiter? An Impact must be huge due the massive atmosphere. (Sidenote: gas giant doesn't mean the Planet is entirely of gas, but light elements. Hydrogen for example has a liquid state, this would still be a gas planet.) > > > Have you ever thrown a ball into water with full strenght? It's hard to penetrate the water very deep. The Liquid will absorb the power of the impact to a big point, same for explosions. So I assume that an impact of any kind is not very effective against a gas planet like Jupiter or Neptun. > > > Beside of this an Explosion can wreak massive havok on solid matter like rock. > > > **Distance to the sun** > > > The sun could be a tool to destroy your planet, if the distance is not to high, you might just push the planet toward the sun. This would take less energy than blasting the planet. > > > [Answer] How about using advanced quantum computers to understand (and thus exploit) chaos? Use a reasonable amount of energy to divert a small asteroid. It crashes into another larger asteroid and diverts *that*. Through picking on successively laeger objects in eccentric orbits and a few gravitational sligshots around the gas giants, eventually you get the Earth's orbit destabilized or a dwarf planet to collide with it. I call it celestial judo. [Answer] I am surprised I didn't see this before (only saw it now because of a link in chat) but I'm even more surprised no-one mentioned my solution, especially in the era of fidget-spinners... Simply add a couple of large engines - I'm thinking Ringworld attitude adjustment engines - on pylons high enough to get them above the majority of the atmosphere, pointed in such a direction as to increase the rotation speed of the earth. Then keep adding fuel/energy (the equivalent of the annoying child who just won't stop spinning that fidget spinner thing!) until the planet gets close to breaking up. Along the way, you'll lose water, atmosphere, people (at about 17xfaster than current rotation) most stuff, to be honest. Of additional benefit, if you can build the engines to run on any matter, you can use the planet's matter as fuel - and if you start using the surface layer round the equator, this will help by increasing the spin speed in the same way ice skaters do by pulling in their arms. Once close to break up, position yourself above one of the poles, set your GoPro to record and wait for the catastrophe in all its technicolour goodness. Read this [question](https://worldbuilding.stackexchange.com/q/40189/188) for more details. [Answer] How FAST do want to destroy it? If you have sufficient resources, try a fleet of [World Devastators from Star Wars](http://starwars.wikia.com/wiki/World_Devastator) to eat the planet (very efficient, saves resources!) or, if you're *really* ambitious, try and make a [Sun Crusher](http://starwars.wikia.com/wiki/Sun_Crusher), which does what it says, by making any star go *supernova*, but that may be a bit much! ... or just enough. Some are proposing you slam things into the planet in question, but I want to propose the opposite: **move the planet into the star**. It might take a really long time, or maybe it wouldn't, but with the right technology (and a little bit of crazy) we can [move a planet](http://www.universetoday.com/112859/how-can-we-move-the-earth/). Our current ideas are painfully slow (and dangerous) but if you have some sort of massive gravity generator, you could destabilize the orbit of the planet enough that, just maybe, it could fall into the star. Or just get a giant wormhole between the planet and its star and boom, same effect. Stargate, anyone? [Answer] A superdense piece of neutron star hitting the earth would accelerate down to the core and then out the other side. If it were not going too fast to escape back into space it would turn around under gravitational attraction and then come back through. This oscillation would go on and on. Stuff would get smashed up as these things went thru. A large number of these things would be more like destroying a building with sledgehammers than with dynamite. It would be dramatic but not immediate and so time for events to take place on earth. I can imagine the sequence where a building sized chunk of neutronium exits the earth near the protagonists, who survive ensuing badness but then realize chunk is going to come back down. Roaches would probably still survive. After superdense chunks come to rest in the core you would need to spray. Greg Bear had something like this in Forge of God. The chunks, not the roaches. <https://en.wikipedia.org/wiki/The_Forge_of_God> but the oscillations were a side benefit; his things were going to destroy Earth in a matter / antimatter explosion. [Answer] Implode the Sun, thus creating a very dense object that's close (?) to Earth. Eventually, the rapidly intensifying radiation from the Sun would scorch Earth into a barren rock - as stars become smaller, they burn more fiercely. [Answer] I'm surprised that no one mentioned nanobots. There's no big boom but if you have nanobots that simply make copies of themselves using available resources, you could end up with a grey goo scenario. the planet is still there but anything that lands on it corrodes into the nanobot swarm. [Answer] I feel the need to answer this question with a website that is dedicated to this answer. <https://qntm.org/destroy> This website provides hard science, and provides several solutions. Please note that it explicitly states that destroying an Earth-like planet is impossible with our current technology. The two most promising answers are to hurl Earth into the Sun, or to rip it apart via tidal forces. The latter also requires moving Earth near a large object, or moving a large object near Earth. [Answer] This is a great question because exactly how planets are destroyed in real life is not something that's often discussed. I wrote a series of blog posts on that subject, called "How planets Die" (see <https://planetplanet.net/how-planets-die/>) There is a whole range of ways that planets actually can and do die (rather than invoking something absurd like antimatter). The simplest is waiting until the central star goes red giant, which will fry anything. But there are likely other ways. Let me brainstorm a few (which depend greatly on the level of technology available): * Deflect a bunch of asteroids (or better yet, comets) to collide with the planet. Best bang for your buck is a bunch of impacts in a row (see [here](https://planetplanet.net/2019/02/15/how-planets-die-pulverized-in-a-deluge-of-asteroids-and-comets/)) * Deflect enough asteroids to gently nudge the planets' orbits into an unstable configuration, which will then have the effect of either dumping all the rocky stuff onto the star (if there are gas giants) or causing collisions between rocky planets (see [here](https://planetplanet.net/2019/02/06/how-planets-die-when-good-jupiters-go-bad/)). * Mess with the planet's climate (see [here](https://planetplanet.net/2019/02/11/how-planets-die-climate-catastrophe/)). This could be done by shutting down key geological cycles, or by dumping a huge pile of pollutants into the upper atmosphere (choose well), or even by erosion from a series of impacts. The full destruction of the planet can come from tidal shredding, but you need to kick it onto a very eccentric orbit first, ideally by triggering a dynamical instability. [Answer] A couple of posts mentioned knocking an asteroid into the Earth's path, effectively killing all life on Earth but leaving the planet itself still relatively intact. I'm surprised no one thought of just repetitively knocking asteroids into the Earth's path. (Btw I read that somewhere else) I mean there are over 1 million asteroids over a km. large in the asteroid belt alone. I don't know if it would be enough but I'm pretty sure having asteroids ramming into the planet over and over again would damage it a lot more than a bunch of nukes. I suppose it wouldn't be too long before the atmosphere would start tripping, and once that's gone every impact will just hurt even more. [Answer] I think I may fail at the timeline being under one day with this approach, but this would work with your lasers approach. The energy involved likely isn't enough to fully counteract the gravitational binding of Earth, but it'll turn the planet into a few chunks and require significantly less energy than simply trying to vaporize the earth. A bit of a combination move of throwing an asteroid at the earth, except we're going to use lasers to do it. Have your death star approach the moon and fire its laser as a large spread heating the side of the moon facing away from Earth as much as possible (not to destroy the moon, but to heat the surface to as extreme heat as possible). This heat vaporizes the moons surface, propelling this material away from the moon, functionally turning that side of the moon into a rocket propelling it into earth. This collision between the moon and the earth won't actually provide enough energy to fully counteract the Earth's binding energy, however it'll definitely tear the two bodies apart and not leave much beyond a barren rock. And all for a significantly less amount of energy than outright destroying the Earth with a laser. Unfortunately I'm not enough of a physicist to calculate exactly how much energy you would need to turn the moon into a self propelled rocket straight into the planet and what angle of impact would cause the best destruction rate for you. The area of the moon that is vaporized needs to both halt the moons orbit around Earth and propel it into the Earth to get the best impact angle. [Answer] "I am starting at boiling the atmosphere to the point where it turns Earth into a dead barren rock with no vegetation, no oceans and no air left. This is as tame as I want my destruction (there's still a giant dead rock left, and I want to wreak more havoc than this!)." Nice! I think most plausible option is: **1. CRASH THE MOON ON EARTH.** Since moon is tidaly locked to earth, put a huge autonomous helium3 harvesting facility on its surface, and burn this fuel through an enormous rocket engine, which pushes the moon prograde until it gets a very high apoapsis. Then make plenty of retrograde burns at apoapsis until it crashes on earth's surface. **2. CRASH THE EARTH ON THE SUN.** Wait until earth + moon newly formed "earthmoon" planet gets cold enough in order to have a solid crust. Build other facilities and rocket engines at the equator, and burn counter-rotational until you get an earthmoon tidal locking relative to the sun. Repeat deorbit manoeuvre ( burn prograde at periapsis plenty of times, to get a highly eccentric orbit, with an apoapsis at about pluto's distance or further away, and then burn retrograde at apoapsis, until final ultimate doomsday. [Answer] I have the idea of time travel, if your planet or your enemy's planet's inhabitants have the tech advanced enough for time travel then you could create a hybrid of some animal (e.g. King Kong) whose genes are wonderfully powerful and set it loose and watch the destruction. Another way is to destroy historical objects sixty, seventy, or one hundred years in the future and do that multiple times and then the time changes in that whole time-line and world happen so fast that the world's physics is broken. Then everything from the planet's evolution to their oxygen supply so that would kill the inhabitants easily. Somewhat destroying and jumbling the world into pieces. [Answer] ## Antimatter Now, a lot of antimatter would be required to destroy Earth. Around 6 septillion kilograms. In other words, in order to destroy Earth with antimatter you would need an anti-Earth to do it. Now if you were to launch that at Earth you would completely annihilate\* it. But though, you would also destroy a good piece of the solar system as well. considering the fact that around a quarter of a gram of it could level a city. The only problem is though that producing antimatter is expensive. But if you built anti-Earth on the outskirts of the solar system and then contained it in a vacuum, and launched it at 50% of the speed of light it would hit Earth in about 8 hours. There would not be a remainder of Earth after this happened. \*Annihilation- The result of matter reacting with antimatter. It produces a lot of energy. [Answer] Almost 3 years and I find one that's been missed: Drop a device into the sun that will explode, causing a shock wave through the photosphere. The idea is runaway nuclear fusion--create an enormous flare that will fry the biosphere. I have seen an estimate that puts the energy needed within the range of h-bombs. Protecting it until it's deep enough would be a challenge, though! [Answer] Most other responses focus on a single approach, but what about a scenario involving more than one concept? There was that fear back in 2008, 2009 that LHC would produce black holes. If your story passes on the future, the complete annihilation of Earth could be the result of the first run of an immensely powerful particle accelerator. Something so big and so powerful that it would make LHC look like a Kinder surprise. This humongous particle accelerator could have being built by megalomaniac physicists, who wanted the most powerful accelerator they could possibly build to get data they could not even imagine. The problem lies precisely there. Maybe the accelerator was so powerful that it tears the very fabric of the space-time continuum on its first run, and matter and energy begin oozing out of our universe through this tear, effectively destroying Earth because it's on the center of this hole. Slowly, then, the tear would "heal itself", because the laws of physics would force the Universe to be a closed space, but enough time would have passed for our planet to be crushed and expelled from this cosmos. It's not just destruction, we're talking about total obliteration here! Or, maybe the accelerator was so incredibly useful that it produced strangelets, or a new kind of particle that's responsible for transforming matter in antimatter. Both would involve chain reactions: Strangelets transforming any other particle in more strangelets, which in turn would convert even more particles in strangelets and so on. In the other scenario you would have to propose a new fundamental force, responsible for maintaining matter, antimatter and dark matter stable, and a mediating boson for this force that can convert one kind of matter into another. This chain reaction would convert matter to anti- or dark matter, with each conversion producing more and more of these conversion bosons. In a few time, the entirety of our planet's mass would had been converted to sterile matter. [Answer] You could somehow induce a singularity close to the planet's core, and the black hole would swallow the planet from the inside. Plus, if you have Casimir power tech, this could net you a lot of free power! So the result would actually outweigh the cost when it comes to power. [Answer] Strange matter could also be a solution to your superiority complex dilemma. It basically turns all of what it touches into more strange matter, although with this method you run the risk of destroying the entire universe. [Answer] Construct a large solar reflector that orbits the planet outside of its moon's orbit. The reflectors centrifugal spin is such that it always focuses light from the sun, onto the far side of the moon. This pushes the moon closer to the planet, gradually changing its trajectory until it falls out of orbit. [Answer] I think everyone has dealt with the real world physics as we currently know it. So what about invented physics? Turn the planet into strange matter via a nuclear autocatalytic reaction. It takes a tiny bit of strange matter to start the process. More than nature has ever generated accidentally via cosmic rays etc. But not so much that it can't be done with advanced nuclear/particle tech. Or destabilise its foundations in the 4th or higher spatial dimension. string theory says there are seven more spatial dimensions that we don't perceive because they are sort of rolled up. The theory is incomplete. They can be unrolled. The planet then rolls out of our known universe. Or have someone put the cosmic censorship theorem to the test. This says that if you try to build a time machine the universe will prevent you from succeeding. So the sun goes nova just like that. (This story has already been written but I've forgotten author and title) Or my favorite: the universe is in fact a virtual reality. Have someone find a bug in its hypervisor and try to exploit it. Even better, succeed in exploiting it, until it's too late to stop the unanticipated consequences. [Answer] **Spin a baseball really, really fast** OK, spin an orb made of a whomping heat resistant material really, really fast, as in light-speed fast, and watch that proverbial baseball's relativistic mass approach infinitiy. *Which will turn the Earth into a black hole.* Doing it in a day means spinning that sucker up to speed in a day. Can't see why you couldn't. Use better than average magnets not unlike a rail gun but in a spherical configuration. Do it in a chamber that's as close to a vacuum as possible to avoid those heating problems as the beastie spins faster and faster. I doubt you'd need to actually receive light speed. All you'd need to do is push that relativistic mass up to the point of collapsing the Earth (and likely the Solar System). [Answer] I'm surprised that nobody has mentioned the recent scare stories surrounding experimental physics. In October 2008, when the Large Hadron Collider was switched on near Geneva, there was some concern that the device was capable of unintentionally creating a *small* black hole. The scenario goes that the black hold would then sink to the centre of the earth, furiously consuming matter as it went. The earth's core would then be consumed in a few hours. The earth would then suddenly flatten out into the shape of a large frisbee ( the accretion disc ) before collapsing in on itself while being consumed. Here is [an article](http://science.nasa.gov/science-news/science-at-nasa/2008/10oct_lhc/) on the scare from the NASA website. [Answer] Well, if you are on a budget, you might prefer to make the planet unusable for humans via the route of poisons that are persistent and difficult to mitigate. Dimethylmercury would have to be one of the candidates for such. One drop is more than fatal. It can be absorbed through gloves and has a high vapor pressure to boot. Very nasty stuff. One of the strongest neurotoxins, it is also easily synthesized, so it is not very expensive. Disperse a million tons of this over the planet and no-one is ever going to call it home. In theory you could clean it the mess, but the cost would make it very unlikely -- plenty of cheaper rocks to inhabit. I know this does not really answer your question as stated (planet is not left in rubble or dust), but it would otherwise be quite effective and it was too long for a comment. [Answer] Reading some of the other answers made me put my geology hat back on. As noted, the energy required to kill a planet from an external source is huge. However, there are natural processes that could be harnessed to destroy the planet. The key to destroying Earth would be to direct the tectonic energy towards destruction. Triggering massive earthquakes along the Ring of Fire could sufficiently damage the atmosphere to make the planet unlivable. Another possibility came from Greg Bear, I think. He postulated the destruction of Earth by destroying or stopping the core. This would stop the magnetic shield around the planet and result in massive ecologic devastation. In his case, the enemy release high density devices that were able to slow and stop the core. The devices also triggered massive tectonic movement and destroyed the continents. I suspect a 1 kg release of antimatter at the core or the introduction of an artificial singularity to the core would suffice. Though I'm unsure of the amounts needed, introducing lots of additional radioactive matter into the deep mantle could, over time, render the Earth too hot to be inhabited. Likewise, an overall increase of surface radiation will render Earth uninhabitable by humans and most other lifeforms. If I were to be writing such a story, I would do something to strip away the magnetic protection we enjoy. All we have to do is look one planet out to see the results of that. [Answer] Well, there are a few approaches you can go. If you want to stay in the realm of hard sci-fi, I suggest a nuclear war. It has been estimated that at the cold war's height there were enough A-bombs to make Earth uninhabitable. Plus, even if there are not enough nukes to destroy the crust, the nuclear winter will still kill most everything. If you are wanting a natural phenomenon, plant a field of Slaver Sunflowers from Larry Niven's *Known Space* series. They will gradually expand, incinerating everything in their wake. Plant them in a remote region with lots of sunlight, so that they can reach undefeatable population levels. This does not qualify for the 1-day limit, but it is nevertheless a good option. Since you clarified that the world in question is earth-like, not earth itself, it probably does not have a sizable moon. As a result, "de-orbit the moon" is not a good option. If you are willing to allow slightly softer science, make a Stargate-style wormhole connecting point A (somewhere in the general vicinity of a quasar) to point B (somewhere in the general vicinity of your planet). The energy, plasma, and hard radiation that go through the wormhole will instantly reduce your hypothetical planet to a *Hitchiker's Guide to the Galaxy*-style "puff of ozone". It has everything you could ever want; its efficient, it gets the job done, you don't have to deal with any angry natives, and best of all it gives you the opportunity to say that they should have checked the sector planning office! [Answer] **Large hydrogen bomb being very deep** - aka the [Armageddon](http://en.wikipedia.org/wiki/Armageddon_(1998_film)) approach, but instead [going to the asteroind](http://en.wikipedia.org/wiki/Rosetta_(spacecraft)) you stay home, dig deep, even deeper ... basically as deep as possible to the Earth core and place huge bomb here. Imagine having there several [Tsar Bomba](http://en.wikipedia.org/wiki/Tsar_Bomba) exploding at the same time. The plausibility of destroying a whole planet to the pieces is very high. And even if you do not succeed, not even the Jedi would feel it ;) ]

[Question] [ I have a super luxury space hotel. It has artificial gravity in the living and shopping area and 0g in some parts of the recreational area. There is a 0g pool available for the guests. I want it to be a large ball of water 10m in diameter. Can it work? I know water can be kept together by surface tension. I saw videos of water balls a few inches in diameter from the ISS, is there a limit to how big it can be? Obviously some of the water will disperse because of the interaction with the swimmer at least, so there will be a recovery and recycling system in place. However I would like the water to just sit in the middle with no infrastructure touching it for most of the time. Is it possible? [Answer] > > There is a 0g pool available for the guests. I want it to be a large ball of water 10m in diameter. Can it work? > > > I don't think you can make this work as you've envisioned it. Let's look at some of the issues: 1. [**Newton's Third Law**](https://en.wikipedia.org/wiki/Newton%27s_laws_of_motion#Newton.27s_third_law) When swimming, you push against the water and the water pushes back on you. You go forward, and the water goes backwards. Water's also pretty good at transmitting waves. The result is that in a spherical pool treading water forces water downward, and that force will travel in a wave down to the other end of the sphere and create a splash there (though if it's going 10m to the opposite end of the pool, it'll be fairly spread out). So every movement of every swimmer is going to cause a ripple somewhere in the sphere. This contributes to the second issue: 2. **No way to keep the water free-floating** Assuming you don't want a hand-wavy solution like some kind of force field, we don't have a good way to keep the water where you want it. Water isn't magnetic, so you can't use a magnetic field, and if you tried to introduce something magnetic into the water it would end up getting concentrated at the center of the pool. You can't use air jets to keep the water in the center - if you're pumping air in (through the air jets) either you need to pull air out or the air will get increasingly dense (until it's dense enough to overpower the air jets). Same thing specifically with the air right next to the water - air will be circulating. That means that there have to be places at the surface of the water where air is flowing away from the water, and water will try to go with it. Don't count on surface tension to save you, either - it's trivial on Earth to create a splash in a pool, and that's overcoming both surface tension and gravity. Also, conservation of momentum is not your friend here - if you dive into the pool and stop, that momentum must be transferred to the pool. So without intervention the pool would start drifting to one side of the room. Also, good luck trying to get the momentum perfectly cancelled out. 3. **Adhesiveness of water** We generally don't think about this too much because on Earth gravity does a pretty good job of helping us get dry. But think about what happens when you get out of a pool - you're still wet. In microgravity, this is a significant issue because the water that's sticking to you has no force attempting to pull it off of you, so you'd come up out of the water and have your face still covered by it. This is an easier problem to solve, though - a little bit of hydrophobic cream on your face (especially around your nose and mouth), and you'll be able to come out of the water and breathe. 4. **Disorientation** Have you ever gone underwater and then spun around? It's pretty easy to lose your sense of which way is up, though once you stop spinning gravity will tell you which way is up. In a zero-g pool, this won't be the case. Once you go under the water, you have no real sense of which way is "up". If the sphere is 10m in diameter, this could be a significant issue - unless you're a strong swimmer, there's a fair chance that you wouldn't be able to swim that far before you run out of air and start panicking. So unless you're okay with people drowning, you shouldn't be allowed to swim without a scuba tank. There are probably a couple other things that I haven't covered here, but these should be enough to help you see that, as awesome as it sounds, a free-floating ball of water isn't a good idea for a swimming pool. I'd suggest instead that you have a tank of water (as large as you'd like it) that people can exit and enter through an airlock. You wear scuba gear when you swim in it, plus the hydrophobic cream I mentioned earlier. Finally, you need to make sure that the water filtration system is able to separate out the air that divers have exhaled and pump only water back in. [Answer] Yes, this is possible. The ball of water could be kept in place with equally spaced air fans to nudge splashed water back from all directions. *However*... At 10 metres across (5 metres deep) there is a serious risk of drowning. In 0g, the adhesion of water and slight difference in density will cause suspended objects ("swimmers") to be enveloped and drawn to the middle of the ball. For an example of how water envelops objects in microgravity, look to [this example of Chris Hadfield and the wet washcloth](https://www.youtube.com/watch?v=Ff7oUycGJRY). Note how the water clings to the cloth and begins to spread over his hands. Scaled up to 10 metres wide, the spreading water will be deep enough to drown in if you can't clear it in time under your own power. Here is another video, with Mark Wiesgel a zero-G engineer, demonstrating how water behaves in microgravity – and [confirming you would be drawn into the water](https://youtu.be/Kkj_FRAmcAM?t=1307). [Yet another video](https://youtu.be/9ZEdApyi9Vw) showing how water sticks to objects and draws them to the middle, this time, a Go Pro camera. Note how the water sticks to the astronaut's hands later – he was being "assimilated" by it. (Remember we're talking about a 10 metre-wide sphere of water too.) Scuba gear might be required. Or guide ropes would need to intersect the ball of water, swimmers would need tethers, or it would need to be a "diving only" past-time (i.e. enough momentum to pass through the ball of water). Another option would be to spin the ball, which would cause denser objects to be pushed outward to the surface, but there is still the problem of trying to escape the water. [Here is a video](https://www.youtube.com/watch?v=BxyfiBGCwhQ) demonstrating how air bubbles converge along the axis of rotation and tea leaves and other objects are pushed outward by the force. Yes, density matters in microgravity. [Answer] Other answers mentioned water splashing away, as a problem. Yes, there will be lots of water splashing away. But really, this is an opportunity: The water which splashes away is sucked in by pumps in the walls once it reaches the walls, then cleaned, maybe the temperature regulated and ejected in jets back at the sphere from the appropriate direction to cancel the sphere's movement away from the center. In contrast to air jets which won't work (where will the air go afterwards?), this should work for at least as long as there are splashy people inside the sphere. The whole area would probably become splashier and splashier with more water droplets mixed in the air, so you would also want some air circulation with a system filtering the water out of the air and putting it into the sphere-replenishing system. But, as said, 10 meters can be dangerous. Swimming should work as on Earth, but carelessly diving around in it without diving gear would not be a good idea. To keep people oriented, you would likely want strong lighting: Underwater they would swim towards the strongest light to get to the surface. You could also * use smaller spheres * Nothing keeps you from directing the jets so as to squish the sphere into another form. For example you could form it into a 5mx5mx2m (bounding box) rounded block kind of thing by mostly firing water jets at it from two opposing sides. * or maybe a 2x10m cylinder? By having the water flow from one end of the cylinder to the other, it would be easy to keep centered, do away with the jets, water splashed sideways would just be added at the existing inflow. Water would stick to your face when you get out, but shaking your head should generate almost as much centrifugal force as Earth's gravitational force (proof: shake your head with long hair. Hair can mount even higher than 45 degrees[1]), easily shaking it off. [1]Diameter increases with longer hair, but still. [Answer] I'm actually going to disagree with a lot of the previous answers and say that while you could possibly create a ball of water 10 m in diameter in a 0g environment, no one is going to be swimming in it. Assuming a perfectly spherical droplet, the pressure difference between the outside and inside of the droplet is going to be $\Delta p = \frac{2\gamma}{R}$ from the [Young-Laplace Equation](https://en.wikipedia.org/wiki/Laplace_pressure), where $R$ is the radius of the of the droplet and $\gamma$ is the surface tension. So for a water droplet with a 5 m radius ($\gamma = 0.072 \textrm{ N/m}$), the pressure difference between the inside and outside will be $\Delta p = -0.0288 \textrm{ Pa}$ (the negative sign is because it's a liquid droplet, so the pressure inside the droplet will be lower than the pressure in the air. What's important here is that this is small. Really small. An air jet moving at 1 m/s stopped by a surface will exert a pressure of $p = \frac{1}{2}\rho v^2 = 0.6 \textrm{ Pa}$. Because the droplet is not a solid surface, this will cause the surface of the droplet to distort locally. When the surface distorts, the local radius of curvature changes. Going back to the Young-Laplace Equation above, the liquid may want to stabilize, which will then cause small droplets to break off. People swimming, or really even just hitting the surface, of the bubble will cause pressure fluctuations several orders of magnitude greater than those caused by a gentle air jet, which means that the bubble would be unlikely to hold together under the force of swimmers. [Erin's answer](https://worldbuilding.stackexchange.com/a/54640/21272) addresses a way to handle this, but once you go to a shelled system like that, you're no longer working with a bubble made just of water. [Answer] What you're talking about is, of course, beyond the science of today. But if, in your story, the science of gravity is far beyond ours, then, why not? I am going to come at this from a safety and logistical standpoint rather than a science standpoint, because really, **you can do anything given the right tech in a fictional universe.** I know, I know, this has a physics tag, but there are more barriers to this than just physics. You asked if it was possible, and I am going to come at it from a slightly different angle. The outer edge of the ball would have to have considerable tension--enough that there shouldn't be dispersal from the swimmers if it's going to work at all. EDIT: *Thinking about this, it should be multi-layered, in order for people to be able to swim: layer one is the outer "harder" layer from which nothing escapes, except for release points, maybe on the top and perhaps the bottom. Layer 2, the inner layer, takes care of the splash and release of bubbles and physics of swimming action, most of which bounces back off layer 1, if it's water.* I would recommend that swimmers have breathing apparatus, because once they are in the ball, they would be under water. It sounds as though you are wanting surface swimming to happen, which should not be possible in this model, unless you are willing to have the top part be flat, like regular water. Otherwise, you risk drowning people, because if it's held together in this way, pushing through the surface tension should be very difficult for swimmers. Even if it isn't, **most people would have a very difficult time orienting themselves in the ball.** I can see people drowning just because they "got lost" and were disoriented. There's also nothing to push off of, no bottom...If there's a way to die, people will find it... There are some logistical problems with no structure touching it. How would the people actually get into the water? The surface of the the water would have to managed minutely, so if you are also planning for people to "float" through the air to get in, that might be a problem. There could be a diving board above, but once they are in, how do the poor sots get out? Here's how I would have it set up: ball 'o water about 5-9 feet above a regular pool. So maybe they dive in above, and then push out, landing in the ordinary water below. The pool beneath would have to mostly be for exiting the ball and not for any other purpose--OR you could have an enormous regular pool where people can swim in the ordinary way, with a part sectioned off, used just for exiting the ball 'o water. EDIT: *So there should be exit/entrance points on the top and the bottom of the ball in case of emergency. This definitely would be controlled, like any slightly dangerous activity such as rock climbing, caving--that sort of thing. I don't see it as something that everyone will want to do or be capable of doing. Time in the ball would be regulated and supervised necessarily.* For safety purposes I would * Have several life guards inside the ball (They would also tell swimmers when to get out, before the breathers run out) * Have each swimmer inside the ball be issued a re-breather of some kind that is difficult to lose, as well as goggles. The people swimming in the ball would be of the adventurous sort--like the sort of people who do zip lining. It would be kids above a certain age, they would sign waivers. I see this as a sort of luxury resort "experience" like those rock climbing walls you find on cruise ships, except more unique. It also adds to the experience of the swimmers in the ordinary side of the pool, because they can look up and see this marvel. [Answer] I'll take a bit of a lateral approach to the question. You don't need water. In terrestrial recreation, water pools are used to combat the gravity (our bodies are nearly as dense as water, so we float on the surface) and propel the swimmers. In your zero-gravity hotel, you already have swimmers able to go anywhere with no regard to gravity. You need to give them techniques to propel themselves (think pressurized cans of whipped cream for a sweet party), and also, possibly, re-create the extent of isolation and solitude we have while swimming underwater (nitrogen fog machines, sound absorbing wall materials). [Answer] Probably possible with today's technology. A key fact is that [**water is slightly diamagnetic**](http://cr4.globalspec.com/thread/98607/Diamagnetic-Water). Combined with (1) surface tension and (2) computer controlled powerful electromagnets surrounding the room containing the "pool", I suspect it could be done. Price of lifting water to orbit may be nearly zero since (frozen) water may be found just flying around out there, and plenty of heat (exposure on the sun side) is also freely available. We can probably figure that the related technology and methodology for comet mining will be available by the time we make space hotels featuring any decent zero gravity compensation (not necessarily "anti-gravity"). First thing I'd worry about would be being trapped inside of it. Water is **wet** and resists things breaking its surface. Once you're fully within it, it could be hard to get your mouth/nose exposed to air again. Water will want to stay spread across them and may "stretch" to keep them covered. There won't be much to push against to force your way through. We don't really know how much (how little) force is needed. The water sphere will tend to keep some shape naturally. Basic inertia will tend to keep its position. Any external magnetic fields would only be used to counter motion of the entire sphere away from center. Magnetic field strengths could be small. (Would be fun to test!) [Answer] Yes, a ball of water, no matter what size (larger is better) can be kept in space in spherical shape. The largest of these water-balls are known as [Ocean Planets](https://en.wikipedia.org/wiki/Ocean_planet) and they are really, really big. Anyhow. Yes, you can do this. Water has strong enough cohesive forces to stay together. Also if you build the *container* of this bubble with a strong hydrophobic substance (such as the wax on leathery leaves), it will help keep it isolated. [Answer] As per the question, artificial gravity is available in the shopping and living areas. If the pool room is also spherical in shape, it would simply need an evenly spaced array of these artificial gravity generators. As the ball drifts towards a wall, a gravity generator on the opposite side could be briefly turned on, pulling the ball back towards the center. If the gravity generators could generate negative gravity then even better - the wall being approached by the ball of water can repel too. A hydrophobic coating on the walls would mean even if the water ball does hit a wall, it would be relatively easy to "refloat" it again using the gravity generators. [Answer] Actually the problem is that people should swim on top of the swimming pool to breath. Even if you succeed to keep the water ball together, anyone who enters to this ball will not be able to go out because surface tension will take the person inside and finding a way to go outside will not be possible. Wow I remembered a very good example now, you can search and see well known "ant in water" issue. Same will happen probably. Good luck! [Answer] The main point here is that in such a large body of water, surface tension will be trivial next to all the other forces propagating through it in the form of waves from any kind of activity. If no one were using the pool and you managed to stabilize the water somehow and keep the air around it completely still (which would be impossible anyway, as vibration from the activities elsewhere in the hotel would be transmitted through the walls) it might stay as a ball for a little while, but very soon it would begin to break up again into smaller balls, as a result of tidal forces (unless your hotel were somewhere deep, deep in interstellar space). And, of course, the moment someone interacted with the water in any way at all, waves would start to propagate through it in all directions, causing a rapid breakup of the medium into smaller and smaller agglomerations. The default state for such a system would be a lot of water balls of various sizes floating around randomly, interacting with each other and other objects, sticking to the walls and the people, and tending to break up more and more when any movement is present and coalesce a little more when there is none. Obviously, in such an environment, a swimmer without scuba gear would not survive, as there would be no known place where he/she could go and be able to breathe. Water could be in any place at any time, and breathing would depend on the lucky coincidence of just happening to have your nostrils in the middle of an air pocket, which, by the way, could close at any moment while you are inhaling (and in fact, WOULD probably do just that, because of the movement of air towards your nostrils). Most likely, nothing bigger than a bacterium could survive in such of an environment for very long -- or enjoy being in it for any longer than it could hold its breath... [Answer] The easiest way to do this (in fact, very easy to do today) is to introduce tension. In other words, rather than just a ball of water, make it water in a ball. This will keep the "pool" from splashing all over the place, and provide the necessary pressure to keep the water liquid if you choose to put the pool in "space", outside of the pressurized compartment. However, do note that you will need breathing equipment anyway. [Answer] Similar to mccdyl001's response, surround the pool with gravity generators. However, instead of only turning them on when the sphere drifts toward a wall, they should be on all the time. Further, they need to be much more finely tuned so that gravitational force doesn't multiply towards the center, but that there be a definite center (perhaps two generations of technology beyond conventional linear gravity generators). Buoyancy should prevent anyone from being unable to reemerge. Strictly, it wouldn't be a 0g activity, but marketing shouldn't be deterred by that fact. Since gravity would be applied equally on all sides, there would be a risk that a person or object that is naturally buoyant might be stuck in the exact center of the sphere. The gravity should therefore periodically shift a couple meters to the side to allow the buoyant person/object to float to the nearest surface. Presumably, a society that has developed such technology will also have automated lifeguards to monitor swimmers' vitals and intervene when needed. ]

[Question] [ **This question asks for hard science.** All answers to this question should be backed up by equations, empirical evidence, scientific papers, other citations, etc. Answers that do not satisfy this requirement might be removed. See [the tag description](/tags/hard-science/info) for more information. # Introduction In our universe, the [cosmic microwave background](https://en.wikipedia.org/wiki/Cosmic_microwave_background) was formed approximately 400,000 years after the Big Bang. It was hot, but within [a few million years after the Big Bang](https://physics.stackexchange.com/a/126133/56299), it would no longer have consisted significantly of visible light. The first stars [formed about 100 million years later](https://www.forbes.com/sites/startswithabang/2017/12/21/when-did-the-first-stars-appear-in-the-universe/), give or take, as larger structures were slowly beginning to form. In my universe, I'd like to see if I can create a period of overlap, where the first stars form while the CMB is still hot enough to be visible to the naked human eye, and exists at wavelengths suitable for chlorophyll-based photosynthesis. I've found by [playing around with the Saha equation](https://ned.ipac.caltech.edu/level5/Sept02/Kinney/Kinney3.html) that I can keep the CMB hot and visible for a few million years more, but only if I increase the baryon density by a *lot*. Therefore, I want to see if I can change my universe's parameters to instead accelerate *star formation* by a factor of 100 or so. I'm not going to change most fundamental constants like the speed of light; that tends to cause issues later on. The parameters I'm willing to change are the various density parameters for photons, baryonic matter, dark matter, and dark energy: $\Omega\_{\gamma}$, $\Omega\_M$, $\Omega\_D$, and $\Omega\_{\Lambda}$. These [evolve over time](https://physics.stackexchange.com/a/397941/56299); [today, $\Omega\_{\Lambda,0}=0.692$, $\Omega\_{D,0}=0.258$, $\Omega\_{M,0}=0.048$ and $\Omega\_{\gamma,0}\approx0$](https://astronomy.stackexchange.com/a/19395/2153). As the first structures were forming, however, the universe would have been matter-dominated (that is to say, $\Omega\_M,\Omega\_D\gg\Omega\_{\gamma},\Omega\_{\Lambda}$). # Structure formation and star formation Given what I know about star formation in the early universe (see e.g. [1](https://www.cfa.harvard.edu/%7Eloeb/Photos/book_10.pdf) [2](https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6395782/), for more information), I think we can break the process down into a couple key stages: 1. Small density fluctuations grow as gravitational instabilities cause perturbations to collapse. These form small dark matter halos rich in primordial gas. 2. This gas [cools mainly after molecular hydrogen forms](https://ned.ipac.caltech.edu/level5/Sept12/Glover/Glover1.html) because much of the gas should exist at temperatures less than $\sim10^4\text{ K}$ - the threshold where atomic cooling is important. 3. When clumps in a gas cloud are massive enough (i.e. reach the Jeans mass), they can collapse to form stars, just as they do today. If I could affect any of the three stages - halo collapse, cooling, or protostellar collapse - I might be able to achieve what I want. The problem is, I don't know how changing my parameters would affect the relevant timescales - if at all. # Existing work I've done a basic literature search on theoretical work on early structure formation. Much of the existing results are based on numerical simulations (e.g. [Abel et al. 2000](https://arxiv.org/abs/astro-ph/0002135), [Bromm et al. 1999](http://adsabs.harvard.edu/abs/1999ApJ...527L...5B)). They assume a universe dominated (at the time) by cold dark matter, i.e. with $\Omega\_D\approx0.95$ and $\Omega\_M\approx0.05$. Using a couple of different numerical methods, they studied the evolution of clumps through collapse. As it is beyond me to reproduce the simulations, I can't even speculate on how they would behave differently in another universe. If there are analytical approximations for the timescales involved, I can't find them. I suspect that there's something out there, but I don't know where it is (cosmology is not exactly an area of expertise of mine). # The question Let's say I want stars to form within the first 2 million years after the Big Bang. What combination of the cosmological parameters ($\Omega\_{\gamma}$, $\Omega\_M$, $\Omega\_D$, and $\Omega\_{\Lambda}$) is needed to cause this? (I assume, that $\Omega\_M$ and $\Omega\_D$ are the ones I should be focusing on.) By simply adjusting the contributions of different types of matter and energy, can I make star formation in this universe begin earlier than it did in ours? ### Requirements I have a couple of requirements: * The universe needs to be stable, and should eventually evolve to become what it is today: expanding at an accelerated rate and dominated by dark energy. * Fundamental constants *not* derived from the density parameters should not change. For instance, increasing the speed of light, lowering the mass of an electron or increasing the gravitational constant are forbidden. I don't want to run into any unfortunate paradoxes or contradictions. * Please note the [hard-science](/questions/tagged/hard-science "show questions tagged 'hard-science'") tag on the question. Ideally, an answer would be backed up by either analytical or numerical results. I'm not asking anyone to run simulations . . . but if you did, that could be amazingly helpful. ### Notes The question's remained unanswered for a while. Aside from the fact that simulations of subhalo collapse might be necessary to address the problem in detail, I think the question could be difficult to answer given our current knowledge of the physics behind it all. There are a few possible sticking points: * I recently got to talk with an astrochemist about Population III star formation in general; it turns out that rate coefficients for the molecular hydrogen cooling reactions are not precisely known. * There are still some discrepancies between different simulations of halo collapse/early structure formation. * We don't have a lot of information about Population III stars. Putting this all together, my question might remain unanswered for a while, but I'm okay with that. If you know of new developments (or old ones) that make this question answerable, and you can apply those properly, please do write an answer. But if we can only speculate - well, I'd rather wait until we can do more than speculate. [Answer] **Increase the starting density of dark matter.** From OP: > > The parameters I'm willing to change are the various density > parameters for photons, baryonic matter, dark matter, and dark energy: > Ωγ, ΩM, ΩD, and ΩΛ. > > > From OP: > > Given what I know about star formation in the early universe (see e.g. > 1 2, for more information), I think we can break the process down into > a couple key stages: > > > Small density fluctuations grow as gravitational instabilities cause > perturbations to collapse. These form small dark matter halos rich in > primordial gas. > > > Dark Matter: <https://www.pnas.org/content/112/40/12246> The benchmark cosmic baryon mass density and baryon-to-DM mass ratio are ρb=(4.14±0.05)×10−31 g cm−3, ρb/ρDM=0.183±0.005. so ρDM= 2.262e-30 The Formation and Fragmentation of Primordial Molecular Clouds <https://arxiv.org/pdf/astro-ph/0002135.pdf> > > 3.1. Formation of the First Objects To illustrate the physical mechanisms at work during the formation of the first cosmological > object in our simulation, we show the evolution of various quantities > in Figure 1... In the first, before a redshift of about 35, the > Jeans mass in the baryonic component is larger than the mass of any > non-linear perturbation. Therefore, the only collapsed objects are > dark-matter dominated, and the baryonic field is quite smooth. (We > remind the reader that a change in the adopted cosmological model > would modify the timing, but not the nature, of the collapse.) In the > second epoch, 23 < z < 35, as the nonlinear mass increases, the first > baryonic objects collapse. > > > This is what we want to do: modify the timing. We want it faster. So: initial conditions right after the Big Bang have dark matter and baryonic (regular matter) spread smoothly. ρb/ρDM=0.183±0.005 and so baryonic matter is 0.18 as dense as dark matter. The initial perturbations are with dark matter - the "small density fluctuations". If dark matter is more dense to start with (and I mean absolute density, not relative to baryonic matter), initial perturbations will more quickly form gravitational nuclei that can later pull in the baryonic matter. More dark matter = more gravity. So we will increase the amount of dark matter in the protouniverse. Collapse of dark matter is the first thing to happen and the more there is the faster it will collapse. We will make the dark matter 1000000 times more dense. **ρDM= 2.262e-24** --- The dark matter will collapse faster. If we make it even more dense can it collapse even faster? Those density values are not very dense especially when you consider the density of the stars that need to happen. I think this answer is within the scope of the hard-to-achieve demands of the question. Increasing baryon density would give a similar result as noted in the OP. I think, though, increasing baryon density would be slower as regards speeding the formation of stars. As I understand it, the primordial baryons are hot and this opposes their clustering. Dark matter is not affected by heat in the same way and that is why it is the first stuff to cluster. [Answer] ### Abraham Loeb has suggested the possibility of an early habitable period between 10-17 million years, with the CMB itself being a potential energy source for habitable planets within this time period *The habitable epoch of the early Universe* [https://lweb.cfa.harvard.edu/~loeb/habitable.pdf](https://lweb.cfa.harvard.edu/%7Eloeb/habitable.pdf) He also provides a means by which halo collapse could have occurred during this time period. I realise this is not quite as far back as you need, but it does seem to bring you a lot closer. Maybe there is enough play in this theory to achieve the desired effect by tweaking some of the variables but I haven't spent much time with it yet. **Thoughts on visible light** * Visible light is arbitrarily related to human vision which is only relevant if there are humans around, if you can replace "human visible" with "visible by some creatures who evolved in the early universe" then Loeb's theory may actually fit all the requirements. Just a thought, please disregard if not relevant. * There are many kinds of chlorophyll, some of which are known to interact with infrared light (<https://science.sciencemag.org/content/360/6394/1210>) these adaptations seem to have arisen in low light environments, so plants which have evolved in this environment could conceivably photosynthesise directly from the CMB during the above time period. *This is a just a partial answer as it doesn't provide star formation at the time when the CMB is human visible, but it does seem to answer the question "can I make star formation in this universe begin earlier than it did in ours?" (or rather it suggests that star formation could conceivably have happened much sooner in our universe than conventional wisdom dictates)* ]

[Question] [ You have a trillion dollar/year military budget. You can buy all the toys (that are physically and financially possible to build with current technology). You can hire the manpower, command the airpower, harness the firepower, fire up the research labs. You've had years to prepare and train. Before you stands the mighty city of Oppela, population (pre-war) about 4 million. Densely built, many high-rises, a metro system, a few wide roads with lots of back roads. It's been taken over by the evil bad guys (at least according to the massive PR-campaign by the media that you mostly control). There's very few civilians left (at least according ... well you get the idea). There's also tens of thousands (maybe 100,000) dug-in, well-supplied and well-motivated enemy fighters, many of whom have vowed to fight your forces to the death. It should be pretty straightforward. Just go in and crush them. The only problem is that for all your military might, your home front is ridiculously sensitive to own-team casualties, and you're about to engage in the largest urban assault operations since [Berlin](https://en.wikipedia.org/wiki/Battle_of_Berlin) (victory, but 350k casualties for attackers) and [Stalingrad](https://en.wikipedia.org/wiki/Battle_of_Stalingrad#Casualties) (defeat, 850k casualties for attackers). **Is it possible (using any and all available tech and the best tactics) to win this siege with near zero (own side) casualties?** You can safely assume that you won't be able to talk your foes into submission (also, playing Justin Bieber songs *really* loud probably won't work either). PS: No nuclear weapons. I have a severe allergy to nuclear detonations. They give me these rashes, makes it almost painful to shower in the morning. PPS: Edited in from comments: > > Q: Are there international or other laws you care to stick to? > > A: I fired my legal team when I was elected to my high office. Nobody told me about any international treaties. If I don't know about them, they don't apply, right? > > > Q: Do you want the city itself to remain physically intact(ish), so that it can easily be repopulated by your guys, or are you happy for it to be flattened if need be? > > A: City? What city? There was a city there? I don't know of any city. But if we're talking cities, we'll build a great, huge city. We build the best cities. It will be glorious. > > > [Answer] I think one of the key issues that you will face in winning this war/battle is if your own population does not fully support it. If your population is totally against losses from the military - I can only assume they are even more against civilian losses. The enemy is likely able to identify that your population maybe don't have the stomach for a bloody engagement. If they are in a no win scenario in a conventional sense they are likely to turn to asymmetric warfare/terrorism. Unless you can rapidly prevent all citizens - civilian or otherwise - leaving the city and being able to travel globally. You may experience a home front terrorism issue. If you have been building up and preparing for years what has the enemy been doing? Sitting waiting? - doubtful. If they have any special forces troops etc they will probably be trained to blend into local populations. If you kill millions of peoples families you will radicalise huge numbers so you need to ensure containment. However if you can ensure containment then basically it is a perfect siege and 4 the million people will just starve to death. Often this sort of resistance would take the form of civilian resistance in the city e.g. Maquis in WWII. However if they can't do that as there are no targets they would likely leave. Many soldiers left their own countries to form resistance units during WWII e.g. Czechs and Poles trained and armed in UK. They then returned to fight in their country e.g. Czech assassination of Reinhard Heydrich. Instead if if they can get into your country you have trouble - as they can form sleeper cells etc. and wait for the right chance. Depending on their cultura they may or may not be willing to launch suicide attacks but many would likely take huge risks to a carry out revenge attacks. Appropriate enemy culture may support suicide attacks as can be seen by Kamikaze attacks in WWII. We don't have to look far to see how that works currently with groups like ISIS. ISIS encourage attacks from cities largely under siege but motivate people with their ideology to launch attacks against civilian populations in other countries. Terrorism against an already squeamish population would likely be highly effective. Also are there elements of the enemy nationality as immigrants or even large number of 2nd generation immigrants within your country? Or even in nearby countries? America had Internment of Japanese Americans to deal with this threat during WWII. Also do you fully control your own population? Are all elements of your own population fully committed to the cause? Depending on your tactics you may radicalise elements of your own population with no actual affiliation with the enemy. The risk would be media images of atrocities could sway your population against the action. This could increase the risk of homegrown domestic terrorism. Obviously propaganda works well here demonising the enemy - making them less than human. e.g. US Bug bunny cartoons of the Japanese used stereotyping to ensure the civilian population were more supportive. So how do you win the battle for "hearts and minds"? Social media? Media blackout? I assume you can't enforce a media blackout and fully control the media otherwise the truth of your own causalities wouldn't matter? This may add another issue if the enemy is willing to stage fake atrocities to gain sympathy and generate support for their cause. Also look at political upheaval caused by anti Vietnam War protest in US in 60s. If the enemies only option is death - you probably can't win their "hearts and minds" so probably need to offer alternatives to prevent "Total war". If the enemy is backed into a corner and conventional warfare won't work and surrender is not an option then they are likely to try these approaches. [Answer] ## Drone warfare Your people might not be disposable but you have the money and you have the toys. There's no reason to actually send any of your people within 500miles of the place. So you lose a few drones, it doesn't matter if you're losing a drone per enemy kill, it's only money and you're not losing people. As a tactic you don't even need to be subtle, just send two more drones in for each one you lose. Think doodlebugs or WWII Russian infantry. Do it by sheer weight of numbers, flying, wheeled and walking. Little 8 legged crawling bombs that could walk up walls, into tunnels and pipes, sneaking into every little nook and cranny would be a morale killer for defenders. Imagine in your most private moment, pants around your ankles and a bomb comes crawling out of the pipe underneath you, Oppela is not going to be a happy place. [Answer] Inspired by a certain politician/real estate mogul: ## Build a high wall around the city. Make it very high, full of automated defenses and airtight. Not inspired by said person, but by [a lake](https://en.wikipedia.org/wiki/Lake_Nyos): ## Then flood the entire city with $CO\_{2}$. This should displace all the oxygen in the city and being heavy, stick around of a long time while also flowing down into the deepest hideouts. Though toxic at high levels, normal diffusion will clear the city and make it safe again after you take down the wall. The only place where people would be safe would be in the upper floors of skyscrapers, where they are very vulnerable to your more conventional weapons, unable to move around and if you cut off electricity and water, they will not last long. Some of them could be convinced to surrender if you want the PR value, though beware of booby traps and suicide bombers. An extra bonus is that no combustion engine will work without oxygen, so vehicles become useless, as do diesel generators. If some sneaky people try to run a generator up high in a skyscraper, you can easily spot the infrared signature and send a missile to turn it off. After the city quiets down, you will need some drones with heartbeat detectors to locate any bunkers that had better air recycling than most. ## Building the wall This is the riskiest part of the plan, though remote controlled construction vehicles can do most of the work. Start with reinforced checkpoints. Make the first ones look vulnerable but fill them with nasty surprises for any attackers from within the city. It should be quite clear that you are trying to lure them out into the open to be cut down. Leave some supply routes untouched for as long as possible. Call your project a "Containment Zone" and declare how it will keep the rest of the country safe from those evil marauders in Oppela. Finish the encircling before building it any higher. Put sensors in the ground everywhere and collapse all tunnels except near the supply tunnels the enemy uses. When you are ready, raise the walls high. Declare your containment zone a success publicly. Then put them all to sleep. The gas itself would be unnoticeable to the entrenched fighters unless they are specifically monitoring it and once it reaches dangerous levels, they will not be clearheaded enough to mount a coordinated response. The benefits of this tactic are that you are not left with dangerous chemical, biological or nuclear materials that might escape the quarantine zone. Also, you don't do a lot of damage to the city itself. The small amount of fighting that's left will have you in a position of overwhelming advantage, either at the wall if they try to break out, or with the enemy trapped in skyscraper, unable to leave. The downsides are that wall builders may be attacked by an overwhelming force in the early stages, that you need time to generate enough $ CO\_{2} $ and of course that you are committing horrific genocide, you evil bastard. Note: I feel dirty just suggesting this tactic and I'm happy this would not be feasible with real-world monetary, resource, political and ethical constraints. However, real-world conflicts have shown us that conquering a city is an extremely costly, bloody and wasteful affair. There simply is no way to keep the civilian population safe and still find and defeat the armed defenders without going into the city and exposing yourself to all they've got. Even after the city "surrenders", individual fighters may pop up and kill a bunch of your people by suicide bombing. Hence the radical decision that no casualties means no potential fighters left. [Answer] Use economics. You have a trillion dollar defence budget, a risk adverse political class, and a massive PR/propaganda machine, why not get them to fight themselves? Offer a million dollar bounty for the head of each of the 100,000 hardcore committed troops your are fighting against. Yes 100,000 heads of your enemy at $1 million a pop would equal 1/10th of your defence budget but all of your troops gets to go home to mom. Plus if you really want to Machiavellian about it many of the people you would need to pay off for the dirty work you got them to do would probably be killed off in the mayhem that follows so you wouldn't need to pay them. Also you could use your giant PR machine to turn the siege into the "greatest reality TV show of all time," and sell advertising space. I'm sure countless defence contractors would beat down your door to sponsor your war. [Answer] You may be overthinking this one. Let's look at the [Gulf War](https://en.wikipedia.org/wiki/Gulf_War) as a contemporary example. The allies deployed 950,000 soldiers against Saddam's 650,000. 292 allied soldiers were killed (half of them by accidents), and up to 35,000 Iraqis were killed. As things go, the trend is towards less deaths due to combat over time owing to technological developments. The 2003 [invasion of Iraq](https://en.wikipedia.org/wiki/2003_invasion_of_Iraq) saw the US led coalition deploying 380,000 soldiers with 172 deaths. It may not be zero, but considering the numbers involved, it's an incredibly low figure. Casualties depend on how evenly matched your forces are with your enemy, and how determined they are to fight. This wasn't just a military conflict; the Americans in particular led a propaganda campaign against both the Iraqi soldiers they were about to fight, and their own people. That would be necessary in your case too. It has been said that America's propaganda, inclusive of [leaflet drops](https://en.wikipedia.org/wiki/Airborne_leaflet_propaganda), were a contributing factor to the surrenders in the Iraqi army. Another case study worth considering is [Operation Cast Lead](https://en.wikipedia.org/wiki/Gaza_War_(2008%E2%80%9309)). This is a good example of the evolution of hardware and tactics to suit urban fighting. And you may like to examine recent innovations from the Israeli defence industry, which are often specifically for circumstances like these; and sometimes it's the little things; like having a gun which [can shoot around corners](https://en.wikipedia.org/wiki/CornerShot). However, in this case (unlike your own) there were many civilians present and killed. In your situation the fanatic enemies may deliberately cluster around what's left of the civilian population, which causes a lot of problems for even the most sophisticated guided bombs. Modern artillery shells can be guided to within meters of their targets when fired from tens of kilometres away, and so if the enemy forces are nowhere near civilians they can quite safely and accurately be shelled into oblivion at great distance with artillery, aircraft, and missiles. Perhaps the waiting game is the best option. Allow any civilians safe passage out, hold the perimeter around the city, turn off the water, and wait. At best it'll be a few months until the defenders are dead or too weak to fight. If they do try and break the siege they'll be advancing into your traps and defences. That would depend on your ability to create and hold a perimeter, assuming they no longer have supply lines. The bottom line is that with patience, overwhelming numbers, and superior technology, you can win with very few casualties. [Answer] From the question, ~~civilian~~ enemy militant causalities are not a concern. this calls for a multi phase operation. Phase one, remove their ability to communicate. Deploy Electronic warfare units around the city and jam all radio frequencies. Destroy all of their radio stations, tv stations, internet hubs etc.. You wouldn't want these ~~civilians~~ soldiers to tell ~~the truth of atrocities being committed against them~~ lies and false propaganda in attempt to hurt the morale of your troops. Then, Take out railroads, roads and ports and airports in the city. You want to deny the population the ability to get supplies in and transport people to outside of the city. You don't need to completely cut the city off from the outside world, but, if you prevent the transportation of large amounts of supplies you will have hurt the city pretty badly. Phase 2. Use aerial strikes to eliminate all medical care facilities: hospitals, clinics, dentist offices, manicurists, barbers. You get the idea. Destroy their water treatment plants, power stations, gas lines, sewage facilities, recycling centers, incinerators. This will cause sewage and garbage to slowly fill the city. They will have major sanitation issues and be ripe for plagues. Now this ~~defenseless city~~ bastion of the enemy is going to have serious issues, all of this damage will either break t he enemy civilians resolve, or, it could strengthen it. (a rare and unfortunate side effect) Phase 3. Deploy your main weapon! There is this lovely disease called the black plague, it has about a 30% casualty and whats more is there is a vaccine for it! Unfortunately for the residents of Oppela most people aren't given this vaccine. So these poor residents will have to depend on getting it from their destroyed hospitals. You can expect high casualties from this attack and, protect your forces from this dangerous disease. Then, hit them with the bird flue, typhoid fever, dengue fever infested mosquitoes. The few doctors who survived your purge will be insufficient to cope with this onslaught of diseases. The final phase of this operation is mop up. You should launch this attack about 3-5 days after you infected the population with dengue fever, it causes extreme muscle fatigue meaning any enemy ~~civilians~~ combatants will be unable to ~~run away~~ fight effectively. A lot of the others mentioned problems that you could have with PTSD and after action suicides in your military forces. I don't know if there is an effective way to handle this, but, you could overcome the negative effects this would have on your civilian population with the right propaganda. Videos of mothers carrying infants and attempting suicide bombings against your troops. 10 year old soldiers charging entrenched positions with assault rifles. This would also help paint a picture about how evil the enemy is. [Answer] Who doesn't like shooting stars? I like shooting stars. They're pretty. [](https://i.stack.imgur.com/6G6gX.jpg) I'll give you a flattered piece of fused glass with zero casualties on your side for a fraction of that trillion dollars: * Make a heavy-duty starship * Take it to the MOON! * Cut moon piece(s) * Take pieces out of the moon * Drop pieces on top of Ebil Oppela defenders * Profit! Now, I'm a fan of dropping moon stuff from orbit. [And who isn't?](https://worldbuilding.stackexchange.com/a/33666/863) So borrowing from there, and let me quote the handsome guy from that answer, since it seems that he know words, he have the best words: > > [...] a 10-ton falling rock from around our Moon's orbit (384,400km) would carry the energy equivalent of roughly 627 Hiroshima atomic bombs. > > > So there you go! Nice fireworks, no Oppela, no messy radioactive fallout, and you saved some pocket change to rebuild the city! [Answer] ## Chemical Warfare Drones as mentioned by @Separatrix are an excellent way to minimize your casualties, but are ineffective when people create tunnels, adapt to living in caves, and start a guerrilla style warfare if and when you choose send boot on the ground. Your first and foremost job would be to surround the city, to minimize smuggled resources, forcing people to rely entirely upon only available resources. Disrupt or destroy electric grids (Artillery/Bombs), water supply (through poisoning), hospitals and any government facilities which would contain gas masks, or medicines. Following a co-ordinated heavy artillery and drone shelling in the midst of ensuing chaos, use either aircraft bombs or binary munitions to completely cover the entire city with Nerve Gas or Asphyxiate. You also have a wide variety of chemicals to choose from. Most are odorless, colorless, and practically undetected till effects start. Most notable ones are Sarin, Novichok, and VX (V Series). This not only ensures high number of causalities, crushes their structure but also, the sight of mutilated corpse with blisters, and agony of the affected but alive population does irreparable damage to their moral, allowing for a much easier surrender. If you are still unsure about it, even Hitler choose not to use mustard/Chlorine gas in WW2 after seeing its horrifying effects in WW1. [Answer] A metropolis is inherently vulnerable to interdiction, if you blockade all the supplies, drop a 500 lb bomb on the water treatment plant/pipelines. Then wait for them to surrender or starve to death. If they have their own food, yummy yummy mil-rats, they will still suffer dehydration with no water. People tend to forget that modern cities are not self sufficient, they rely on a steady input from food production areas (farms) and water processing: interrupt that and everybody dies. (and not quick and clean either) A military installation might have its own hardened water supply, but probably doesn't. They also might have sufficient supplies of shelf stable foodstuff that everyone hates. But most military would need a really good reason to invest in such things, and a good attacker won't give them a lot of advance notice. So what you are left with is IF there is a military base inside the metropolis (most are not) then it might have water available, otherwise you can kill them by denying water/food. [Answer] I think it depends on the time scale that you want to re-take the city in. A medieval siege was usually conducted because the casualties that would happen in a frontal assault were not deemed acceptable to the attacking force. In addition to really loud Bieber (Might as well try) you just stop all incoming food and services from a distance far enough away to be out of combat range of the defenders. If you can lob in some rockets, bombs, artillery from that safe distance (including very high level planes in this) then add that into the mix as well. Eventually the defenders will starve, get bored, die of old age without you taking a single offensive casualty. It may however take some time and they will probably destroy most of the city themselves before you get it back. [Answer] You may want to define "winning". I assume you want to own this metropolis, and not just own a really impressive pile of junk. I take it that you are not interested in survivors (the kind of stories they keep telling can be very upsetting for the tender and fragile souls of your people on the home front, and noone wants that, right?) So, i would say that carpet bombing, in spite of all the fancy visual effects it provides, is not an option (also, it's simply not hipster enough) Using gas or biological weapons sounds like a good idea, at least as long as your weather forecasts are reliable enough to predict wind directions for a few hours. Unfortunately, gas masks are a thing, and while you could deminish the enemy forces over time, you simply cannot get them all in one go. Separatrix already suggested the coolest option: 8-legged bombs walking up walls. So i will use a much more cynical and direct approach: **Just hire mercenaries.** They are not your own people, so the home front won't care. Since you have the money and the toys, hiring them, offering a substantial bonus for secondary goals (like leaving things standing, doing some basic cleanup of leftover enemies, and whatnot), and of course supplying them with all the fun toys your precious military industry provides, you should be all set. Especially if you are not in a particular hurry. As a bonus, if things go haywire, you already have someone to blame. Obviously, that's still not particularly hipster. But we can fix that, by supplying them with power armour, at least officially attemting to make them bullet proof, and, the most important part: provide them with biodegradable ammunition! This will clearly tell your sensitive people on the homefront how really really nice your war is! [Answer] Convert your trillion dollar budget into pennies. According to [the megapenny project](http://www.kokogiak.com/megapenny/four.asp), one cubic foot of pennies is about $500.00. So for a trillion dollars you end up with 2 million cubic feet of pennies. Then in the name of peace, "donate" all the pennies to the city. Donate them with bombers, with catapults, with shotguns and sling shots. Even if 2 million cubic feet of shiny, slippery coins, delivered at velocity, is not enough to kill and bury the entire population of the city, it is enough to block up a lot of doors and roads, fill up the sewers and generally make life miserable for the bad guys. Then, one year later, when your military budget renews... do it again! I guarantee that within a decade or two, you won't be able to even see that city under the enormous pile of coins. And as a bonus, once you've destroyed your enemy through pennicide, you can re-enter the no longer defended city and take all your pennies back! [Answer] **Carpet bombing, regular bombing, and just, like, lots of bombs** You don't need nuclear weapons to cause an absurd amount of damage. You'll obviously need more bombs, but there's nothing that a good carpet bombing can't solve (except of course if your problem isn't about destroying stuff). Bombing is a tried and tested way to level a city. It just works. But it does take some time. It might give some people some time to evacuate underground. Underground is significantly harder to reach with bombs, though if you succeeded in driving all enemies from the surface, that's a definite step in the right direction. They're trapped, they won't be able to do much (unless they are crazy prepared with secret underground bunkers full of weapons and access to super-secret defense system that is bomb-proof, but that's a rather small probability). I'd suggest thermobaric bombs, which are the closest you can get to a WMD without being one. Thermobaric weapons put the emphasis on the heat and shock waves, much like a nuclear weapon really but without the radiation. That will be super effective against all building types. Also, a little technical fact for you, thermobaric weapons are alternatively called "fuel-air", because they consume oxygen. Such a weapon in an enclosed space can do quite some bit of damage by effectively sucking all the air. So even underground, people aren't safe from those. **Biological weapons, gas, and other banned weapons** Enclosed space is also a good territory for biochemical weapons. If you can seal subway entrances (hint, you can use bombs for that), it's only a matter of pumping enough gas inside and guarding all known exit points. That obviously presumes you have bombed the surface first and people have fled underground. You could instead just poison the water system (and the gas system, why not). However, I personally advise against that. I'm not a fan of biological warfare. You never know when bio weapons will come back to bite you in the gluteus maximum. Gasing people underground is relatively safe, but a virus in the wild is uncontrollable. Especially if the virus is designed for maximum casualty. But hey, it's your war. **Random acts of terrorism, electronic warfare and general chaos** Some people just want to watch the world burn. Chaos is a powerful weapon. At worst, it can help soften the enemy before you strike which is always useful. If the real world tells us anything, it's that terrorism can successfully divide people. You just need exactly one bad apple to prompt some people to declare a whole ethnicity to be a bunch of terrorists, and I wish that was exaggerating. And you know what they say, divide and conquer. You just have to take it literally. You can also create social tensions and divide people in other ways, but they are less immediate and usually a byproduct of decades of (in hindsight) bad policies. That last one implies access to your enemy's decision-making process, which means at that point there are more effective things you could do (like petition for secession, start a war with someone else, etc.). Electronic warfare is another good approach to creating chaos, and really all you need is to cut the power. A simple blackout is more immediate than a long propaganda warfare, and it has the added advantage of denying your enemy access to electricity. [Answer] *cntrl-f: starvation - 0 results* Hm, are you guys forgetting something? There's no time limit on capturing the city, so - **starve them out**. It's a metropolitan area with probably 0% arable land and 4 million hungry mouths to feed. Bomb their wells, cut off their water and food supplies, and give them a clear route to escape - they'll leave on their own after a year or two. Make sure you use mostly captured soldiers and civilians from their side to clear the booby traps. [Answer] Warning, I am going to mention some really gross stuff here. I will not post pictures. You may probably want to google for images. Don't do that if you cannot stand some really disturbing gory images. You are going to need: * A few dozens of elite spies; * Access to a number of hospitals, veterinary clinics, biology labs, and the cities water supplies and treatment plants; * Large amounts of the rabies virus; * Tons of poisoned Krokodil. Krokodil is the key here. It is a powerful analgesic, and also a very addictive drug. But you don't want it for these features. You want the cheaper, street variety of the drug, which causes skin and muscles to rot and fall off the body. This drug can do so in a very dramatic ways, which has caused some people to call it 'the zombie drug'. Innoculate some hospital patients with rabies first. Do so for a few months. Let doctors diagnose people with it. Let the media know that there are mysterious, unexplained cases of human rabies happening to people eho had no contact with animals. This may cause some small amounts of hysteria, and people will want to be vaccinated. You've got to sabotage their vaccines supplies. Be stealthy - make it so that people are only being injected with Saline IV. Next, pick a few hospital patients and kidnap them. Take them to labs. Apply Krokodil and other drugs on them and use psychological torture on them. Make them violent and broken. Starve them. Then release them, few ones and days apart at first, in the slums o the city. Also gore and kill some innocent people in the slums to make it look like your Krokodil victims killed them. Bonus if the Krokodil victims have body parts of other missing people in their stomach when you release them. There, the city now thinks it has a zombie plague happening to it. Drive the hysteria up a notch by poisoning the water supplies with the poisoned Krokodil. Innoculate stray animals with rabies, and home pets in clinics too. Scale this up until people start fleeing the place. At some point it will become a ghost city, with only a few thosand people still living in it. They should all be either scavengers or that kind of people who build bunkers to survive for years isolated from the world. These guys will be less than a skeleton force when you finally send your military in, probably disguised as an international zombie investigation and cleanup task force. [Answer] Assuming you have the time, you may ***starve*** the city into submission or ***'poison the well'***. But surely these have been considered? I noted that you mention a severe allergy to nuclear weapons. I'm wondering if perhaps you will be somewhat less allergic to the nuke's ugly cousin? **Mr. Neutron Bomb.** There's only one way to find out! He's still out there, somewhere (supposedly banned by treaty?) He'll make short work of Opella's population, and leave the city infrastructure completely intact (except the electronics, which may become slightly fried). Your army should be able to walk in there within a few weeks. Not even the cockroaches survive. [Answer] ## Just buy the city Alaska comes to mind here, once owned by Canada, it was then sold to Russia and then to America. Now this is a land mass rich in oil and was sold finally for a total of +4 billion. If I have 1 trillion dollars and only 4 million citizens, I can buy the city from the mayor and rise the rent to the point where the remaining 3999999 citizen just move rather than pay $100000 a month for water. [Answer] You can try the old fashioned approach. Why bother with fancy new weapons technology. Stick to the tried and true. Fire bombing. With your budget you can afford squadrons of heavy bombers to unload thousands of tons of napalm and phosphorus bombs on the city. Today we better meteorology, geodetic and terrain mapping and computer modeling it should be possible to know where to drop the bombs to ensure the maximum probability of a fire storm starting and spreading through the city. Will this work? Of course it will, remember Dresden and Tokyo. There were post-war studies reviewing the effectiveness of old-style aerial bombing. They can be used as a planning manual for this operation. This strategy will soften up the Bad Guys occupying Oppela. Tank divisions can be sent in to mop the rest of the demoralized population and finish off the remaining soldiers. [Answer] ## Nuke it from orbit. It's the only way to be sure. This might be a pretty boring answer, but if your obstacle is a city, and removing the city would give you success, then that problem is fairly easily solved. Bombing cities has been the best way to destroy cities for a long time now- why change the status quo? Yes, yes I see > > PS: No nuclear weapons. I have a severe allergy to nuclear detonations. > > > So **conventionally bomb it from orbit**. (A much less catchy and memetic headline though.) We have [pretty big non-nuclear bombs](http://www.popsci.com/military-aviation-amp-space/article/2009-08/pentagon-wants-deploy-largest-non-nuclear-bomb-next-year). And who says you have to just use one anyway? Or not from orbit: drone bombers would probably be more effective anyway. If you actually want the "orbit" part, or have something cooler than normal bombing- [just drop stuff on them from space](https://en.wikipedia.org/wiki/Kinetic_bombardment). It's called kinetic bombardement and I hear it's pretty deadly. PS. Loudly playing The Bieber might have more effect than you give it credit for. There are such things called [sonic weapons](https://en.wikipedia.org/wiki/Sonic_weapon), after all. [Answer] Start by airdropping propaganda pamphlets and posters urging the people of the city to lay down their arms and resist the corrupt rule of the elites who brought this conflict upon them, blah blah Edward Bernays blah. If the effort does not succeed - as it will likely not - schedule a carpet bombing run that fully encircles the city with a one-mile radius. After the ring of fire is dropped, demand unconditional surrender. At night, send (hopefully automated) non-military vehicles (such as the Red Cross) to take as many civilians away from the city as possible. Make the noncombatants think of the conflict as their rulers' fault rather than an ultimate fight to the death. If you have drones, use them to prevent enemy combatants from commandeering the vehicles or preventing civilians from escaping. The next day, repeat the ring of fire with a one-half-mile radius. The next night, repeat the Red Cross run. The next day, repeat the ring of fire with a one-quarter-mile radius. The next night, repeat the Red Cross run. The next day, send as many vehicles as possible and economical to take civilians away from the conflict. Spend the entire day doing this, from dawn till dusk. Once the sun is down and the sky is black, repeat the ring of fire with zero radius. Continue each ring of fire every hour with decreasing distance from the city center. At daybreak, resume the evacuation operation. At night, resume bombing. In the end, you either get surrender, or a city blown to smithereens. Either way, you troops can go home. [Answer] Are you sure submission is impossible to achieve? If you buy all the core services (water, electricity, hospitals, public transport, internet, private security, ...) through a network of shell companies, you can shut all down at the same time. I can't imagine a reason why the existing government wouldn't surrender unconditionally the city to avoid anarchy. [Answer] I'd have suggested a neutron bomb, but was beaten to it by PCARR. Second choice, a satellite in synchronous orbit that beams down powerful X- or gamma-ray radiation. This will induce radiation sickness in anyone in the city that is in the open, or inside non protected buildings. The satellite can be protected against anti-satellite rockets launched from the metropolis by AMMs under your control near the metropolis. Or from other satellites with AMMs, but watch out for the resultant space junk. Third choice: Seed the city with radioactive materials (preferable neutron emitters), with a half-life of around a day. This will kill (or at least seriously sicken) anyone exposed to it, but after a month, the radiation will drop to background levels, assuming that the decay products are not radioactive themselves. Finding a suitable material is left as an exercise for the interested reader. [Answer] Chemical or biological weapons blitz, or if they have the technology, nano weapon blitz (grey goo with kill switch). (Adding links as I'm not sure why my original answer was flagged by moderator? A simple solution for a simple question.) <https://en.wikipedia.org/wiki/Biological_warfare> <https://en.wikipedia.org/wiki/Grey_goo> [Answer] The simplest way is pretty boring: just starve them out. Cities have very high population densities - a lot of people in a little space. Cities don't generally produce any of their own *anything*, especially food, and the supply has to be extremely high to keep up with demand. Put checkpoints on all major highways and stop trucks from entering the city. Most grocery stores have to be stocked weekly or they'd run out of food just from regular business. Two weeks into the blockade, the population of 4 million will turn on that little group of 100,000 for their supplies. Bonus: No real structural damage will be caused to the city buildings, aside from a few riot fires, and if you time it right you could (optionally, as an evil overlord) save the majority of the civilians, which is good PR. [Answer] My dear leader, If you will allow me the great honor of serving our glorious nation, I will, with somber heart and determined mind, rid this planet of the scourge that is Oppela. I will begin with the judicious deployment of bunker busters in a grid pattern at quarter mile intervals across the entire region. This will open the evildoer's tunnels and dug-in positions to the air. Oh, what wonders we have in air. Your loyal servants will then follow with numerous vacuum bombs, fuel air blasts, thermobaric weapons! OH THE SPLENDOR! Yes, it will be WOUNDEROUS! For good measure, we'll dump thousands of gallons of diesel fuel on the rubble and ignite it. Once the rubble cools, your great city is ready to be built. A city worthy of your greatness, oh leader! On second thought, perhaps my colleagues over at Evil Genius Community Hospital can formulate a salve for that rash! [Answer] There are a number of ways to go about it, most of them are simply old school mass destruction, with the suggested methods like: * Burn it all (firebombs/napalm for example) * Drown it all (a wall around the city, then fill it with water) * Irradiation to kill everything * Biological warfare * Chemical warfare They all basically do the same, but in different ways. Then there's time-based stuff, like waiting them out, they will starve eventually, but that may be problematic if there are men, women and agriculture, they could just be a tiny country in a city. But, what about semi-sci-fi-stuff? You could make a big bowl/dome, place it over the city, and just suck the air out. Not a nice way to kill, but effective all the same. Or what about digging away the ground underneath the city, then blow whatever supports keeping it in place so it sinks into the ground. Fill up the now dug-inside-a-hole city with concrete, problem solved. The issue with most things is (as some have already posted): * You may have limited time * You may need support from your own people * You may want to have the city be useful afterwards You could solve some of it by simply building a completely new and identical city somewhere else, since you have plenty of money, and just ignore the other one. Or go live in space and shoot any rockets down they might develop over time. Maybe destabilise the planet's core and have it tear itself apart while you're at it. If you want to keep everything as-is, and just get rid of the people in the city: biological or chemical are probably the best choices, unless a kind of radiation is available that will not remain there for long. Gas masks don't last forever, and you can't live in a bunker for all eternity, so eventually you'll get them all. [Answer] if time and civilian casualties are non-issues, then siege is definitely the way to go. just start by using drone aircraft to kill anyone that leaves the city. then use drones to fire-bomb any gardens visible from the air. the city will starve to death within weeks, perhaps months if they are seriously over-provisioned. bombing the water and power infrastructure will accelerate the situation substantially. [Answer] I'm surprised no one has thought of using a genetically modified virus to wipe out the garrison. Three days to kill off the population, three days for the virus to die off and you can use POWs to clean up the bodies afterwards! [Answer] This would be a typical siege. Surround them and starve them out. Cut off all power, fuel, and water coming into the city. 4,000,000 people eat a lot of food, drink a lot of water, and produce a lot of sewage. Dig in and create your own defensive fortifications. If they come out of their city they'll be mauled. Use your tech to maintain air superiority. Control the local roads. Blockade sea access. Shoot everything that moves per the Allies over Germany in WW2. If you detect them massing troops, your loitering stealth bombers discourage them. [Answer] Just to get this straight: * Our guys are running an evil propaganda network * Their guys are the sole defenders of a (possibly) abandoned city * We want to kill all of their guys without losing any of our guys 100,000 motivated hostiles is a huge number, especially in a city. A big, big bomb would be the simplest way to deal with this, but you don't want to do that. I'm guessing the city isn't really abandoned? **Starvation** is a sure strategy, but it will take a while for all the Twinkies and pickles in Oppela to spoil. **Disease** goes hand in hand with starvation. These things happen naturally to a city under siege. As long as our guys keep the vigil, their guys will die off or surrender. We can do this with primitive tech, so we can put the best available stuff to finding all their supply tunnels and tracking smugglers. Better yet, contaminate the food that gets smuggled in. But here's the thing: it sounds like our biggest liability is our own population. They don't want us in Oppela. They don't want our guys to get a hangnail taking the city. They are against us in spite of our best propaganda. **Instead of taking Oppela, let's join forces with the rebels and conquer our own population!** ]

[Question] [ **This question asks for hard science.** All answers to this question should be backed up by equations, empirical evidence, scientific papers, other citations, etc. Answers that do not satisfy this requirement might be removed. See [the tag description](/tags/hard-science/info) for more information. A [livescience.com article](http://www.livescience.com/14667-tall-trees-grow.html) claims that trees can reach a theoretical height of 400 to 426 feet (122 to 130m). This is due to the tree being unable to carry water up to the top at that certain point due to gravity. It also claims that > > at a certain height, leaves (or, in the case of redwoods, needles) are not cost-effective — the energy they rein in through photosynthesis doesn't pay for the energy it costs to bring them water > > > I'm interested in designing a tree that's much taller than 130 meters. Specifically, I'm interested in creating a titanic "world tree" that exceeds the theoretical height limit. The world tree would have a ludicrous amount of leaves for photosynthesis. [](https://i.stack.imgur.com/vKw1g.jpg) Provided the perfect conditions for growth, what methods could the tree use to ferry the water upwards? And what would the limit be in that case? I'm assuming that there are other factors that could limit tree growth besides the inability to ferry water to the top of the tree; for example, after a certain height the wood of the tree may collapse on itself. To be slightly clearer, I would like a list of evolutions/adaptations that would allow this tree to exist under perfect conditions and stability and what its height limit would be in that case. I can understand that such a tree with conventional earth trees impossible, that the limitations of wood would debilitate its height, and that it would not go over the troposphere due to temperature and air conditions Thanks for the answers,tho I don't think I'll be messing with the gravity Thanks to Brythan and Hamlet for the edits :D --- **N.B.** Read the requirements for the [hard-science](/questions/tagged/hard-science "show questions tagged 'hard-science'") tag before answering! [Answer] Assuming you can fix the water problem using some of the other answers given, like having pools along the height of the tree, extracting water directly from passing clouds, etc., you will still have to deal with the tree crushing itself under its own weight. The following is an engineering kind of answer to the question. # Short answer The equation that determines the maximum height of the tree is: $$H\_\text{max} = \frac{\sigma\_\text{allow}}{\rho g}$$ Where $H\_\text{max}$ is the maximum height of the tree, $\sigma\_\text{allow}$ is the compressive strength of the wood, $\rho$ is the density of the wood, and $g$ is the acceleration due to gravity on your planet. What does this mean? Well, the tree's height is directly proportional to the strength of its wood, so if the tree evolved to have ultra-strong wood it could grow taller. It is inversely proportional to density and gravity, so if the tree evolved to have extremely lightweight wood it could grow taller (maybe it uses some metabolic process to make balloons of lighter-than-air gas to support its weight too? that would be cool). Finally, as was mentioned in another answer, the lower the gravity the taller the tree. Halving the gravity doubles the possible tree height. Note that it doesn't matter how big the tree's base is, it will still crush itself as it gets taller. This falls out in the derivation below if you want proof. # The math Let's consider the simplifying assumptions that the tree has a constant cross-sectional area $A$ along its height (for example, a cylindrical tree would have $A=\frac{\pi}{4}D^2$ where $D$ is the diameter) and that we can ignore wind forces and things that could tip the tree over, focusing just on the compression experienced at the bottom of the tree. The weight of the tree would be density × volume × acceleration due to gravity: $$W = \rho V g = \rho A H g$$ (where $\rho$ is the density of the wood and $H$ is the height of the tree) The ability of the tree to carry a load is described by its "compressive strength" which is basically the amount of "stress" the tree can take before breaking. Compressive stress at the base of the tree is the weight divided by the area of the base: $$\sigma = \frac{W}{A}= \frac{\rho A H g}{A} = \rho H g$$ The area in the numerator and denominator cancels out. Now we can rearrange to find the maximum allowable height: $H\_\text{max} = \frac{\sigma\_{allow}}{\rho g}$ # Example An oak tree on Earth could grow to a max height of $691\ \mathrm m$, given a wood density of $600\ \mathrm{kg/m^3}$, a strength of $4\,070\,000\ \mathrm{N/m^2}$ and acceleration due to gravity of $9.81\ \mathrm{m/s}$: $$H\_\text{max} = \frac{4\,070\,000\ \mathrm{N/m^2}}{600\ \mathrm{kg/m^3}\times9.81\ \mathrm{m/s}} \approx 691\ \text{m}$$ Material property sources: <http://www.engineeringtoolbox.com/wood-beams-strength-d_1480.html> <http://www.engineeringtoolbox.com/wood-density-d_40.html> --- # Edit: Additional information As mentioned in other answers, there are additional factors limiting tree growth. [This paper](http://www.nature.com/nature/journal/v428/n6985/full/nature02417.html) from Nature describes the limiting factors in some detail. It mentions that the theoretical maximum water transport height may not be reachable because as the pressure drops it can lead to embolisms within the xylem, which can cause nearby branches to die. Trees can try to mitigate this risk by reducing the size of their stomata, but that also decreases photosynthesis, meaning the top of the tree has a much harder time generating nutrients. According to their estimates, this limits the maximum height of trees on Earth to somewhere around 130 m. [Answer] **This question asks for hard science.** All answers to this question should be backed up by equations, empirical evidence, scientific papers, other citations, etc. Answers that do not satisfy this requirement might be removed. See [the tag description](/tags/hard-science/info) for more information. **Water Basins** If every 300ft or so the tree grew water basins to catch rain, (or maybe as a place to deposit water that it had already pulled up from below?) the higher parts could draw from these basins instead of directly from the ground. This can also lend itself to the fertilization as well. If these basins were large enough they could become small ponds or lakes that could support life. The animals/plants/fungi/whatever that migrate, live, and eventually die there could become the primary source of nutrition for the world tree. The limiting factor would come down to how high can you stack wood before the bottom most block is crushed by the weight. Because this is an alien(magic?) world you could always say as the tree grows old instead of outright dying, it carbonizes into some carbon fiber structure that allows it to withstand the immense weight of itself? [Answer] **This question asks for hard science.** All answers to this question should be backed up by equations, empirical evidence, scientific papers, other citations, etc. Answers that do not satisfy this requirement might be removed. See [the tag description](/tags/hard-science/info) for more information. * **Transport :** Due to transpiration, water can go upwards in trees, however after a certain height the pressure won't be enough. **A way to counter this would be if the tree had a heart of some sort to act as a pump. *Also, the tree can absorb water from outside, so the leaves at the very top can still receive water.*** ( You can also decrease gravity in that world.) * **Lifespan :** It will take a really long time for a tree to grow to that height, it can't be done if it lives only for 30 years. So the tree would have to be pretty much immortal **and** fast-growing, because even 3000 years is too little. **A way around this would be a tree whose offspring grow from itself (it is self-fertilizing, and the seed remains in the tree). So the tree will continue growing.** * **Nutrition :** A tree that big needs lot of minerals. Which is hard to get if it's stuck in one place. **A counter would be if there were bacteria that excrete the minerals required for the tree, and also depend on the tree in some way. *Also it can have some sort of 'basins' which emits a scent that attracts bugs. The bugs fall in and are dissolved to provide the nutrition.*** [Answer] **This question asks for hard science.** All answers to this question should be backed up by equations, empirical evidence, scientific papers, other citations, etc. Answers that do not satisfy this requirement might be removed. See [the tag description](/tags/hard-science/info) for more information. If you significantly relax your concept of "tree", then consider this: an enormous buoyant "crown", attached to the surface via a long, lightweight, flexible "trunk". On a planet like Venus, with its very dense CO2 atmosphere, there are a variety of gases that could provide the necessary buoyancy. One gas that comes to mind - oxygen! It [has a lower molar mass than CO2](https://space.stackexchange.com/a/8135/14337) and, as a bonus, is a natural product of photosynthesis. The tree could start out growing on the ground, and then grow out some kind of bladder that captures the oxygen produced by photosynthesis. As the tree grows older, both the stalk and bladder grow, lifting it higher into the atmosphere. For water, your atmosphere could have a reasonable water vapor content - not so high as to make the atmosphere lighter than the gas bladders, but enough that your "trees" can extract the water they need directly from the atmosphere. If your atmosphere is fairly well-stratified, the denser CO2 would sink to the bottom where it can provide more support, while the lighter water vapor would rise to the top, where your crown/bladder apparatus can extract it. This would give a double-incentive for trees to grow as tall as possible - more light **and** more water the higher up you go. The limiting factor would be at the point where the atmosphere no longer has sufficient density. ## Potential problems ### Gravity You may need to play with the mass of your world such that the buoyant forces are enough to overcome gravity. ### Respiration Plants need to respire just like the rest of us - this means consuming oxygen. They could consume some of the O2 they've stored in their flotation bladder(s). They might start to slump a bit at night, when at peak metabolic rate ;-) [Answer] The tree's [ability to lift water](http://science.howstuffworks.com/life/botany/tree-grow.htm) would scale quadratically if the gravity of the planet were lower. Thus, on a hypothetical planet with **half Earth gravity (`g = 5 m/s^2`)** the tree could attain a height **four times as it would on Earth**. If your planet had the Moon's gravity, for instance, the tree could reach a height of **four kilometers** high. Note that BarbalatsDilemma mentions in [her answer](https://worldbuilding.stackexchange.com/questions/48435/would-a-world-tree-be-feasible-in-real-life/48470#48470) that once we remove the limit of water transport, the limiting factor of tree growth will become the wood's ability to withstand compressive stress, which increases linearly with height. **In fact, the strongest woods are from those trees which grow the tallest.** Therefore once the water transport limitation is removed, the tree may have reason to develop yet stronger woods. To address concerns of lesser gravity affecting the planet's atmosphere, I present [Titan, a moon of Saturn](https://en.wikipedia.org/wiki/Titan_(moon)). This moon has an **atmosphere thicker than Earth's atmosphere**. To address arguments that the atmosphere may be possible only due to the lower temperate at Titan's location, the leading theory of the origin of Titan's atmosphere is that it is caused due to low silicate content in Titan's crust, so *everything* is volatile. Thus, a higher temperature would actually increase the sublimation rate and *thicken* Titan's atmosphere. The higher temperature would expand the atmosphere, but so long as that atmosphere remains inside Titan's Hill sphere it would remain and cause even higher pressures. Titan's Hill sphere is about 50,000 KM, current atmosphere reaches about 1000 KM above it's surface, and volume increases by the third power with increasing radius. Note that these volatiles are organic materials, in particular hydrocarbons, so they would actually support plant growth very well. [Answer] **This question asks for hard science.** All answers to this question should be backed up by equations, empirical evidence, scientific papers, other citations, etc. Answers that do not satisfy this requirement might be removed. See [the tag description](/tags/hard-science/info) for more information. the tree can utilize some form of <https://en.m.wikipedia.org/wiki/Atmospheric_water_generator> which would allow it to collect water from air itself. It would get water directly from the clouds and water vapor itself. I guess the leaves can act as a net to allow water to condense and is then absorbed by the leaves itself. With the help of Google,<https://en.m.wikipedia.org/wiki/Troposphere#Temperature> I highly doubt the tree can survive past 6000 km depending on where the tree is situated as temperatures would start decreasing drastically near the tropospause and air would get thin. As for the trees support and weight, I'm thinking that it would have to evolve a kind of multiple tree trunk that winds together? A trunk that twists together might be a better support for the lower part but it would straighten out as it gets higher to avoid even more weight pressing down. For the amount of leaves needed to support a massive tree, the branches would need extra strength by either supporting each branch by intertwining[might be disastrous if the bottom branches break] or by 'braiding the branches' which should increase the weight it can hold. Otherwise, it might be a nice little cheat to have your tree be supported by a really really tall steep cliff[part mountain part tree]? [Answer] **This question asks for hard science.** All answers to this question should be backed up by equations, empirical evidence, scientific papers, other citations, etc. Answers that do not satisfy this requirement might be removed. See [the tag description](/tags/hard-science/info) for more information. **Symbiosys** Life forms like little insects and birds search protection in the tree, the tree get water from animals urine and from air umidity (using sponge like leaves). **Primitive refrigeration** The leaves could have a shape like a double "u" that is great for converting wind energy into mechanical energy, the side effect of that is that wind get cooler, allowing condensation of water (even if in very small amout). **Symbiosis II** Certain life forms could actually evolve to bring water to the tree and get in exchange small fruits, if the tree is that big it is likely it has a complex ecosystem inside it wich would make the tree also a isolated system. This is for getting water. For getting instead great height instead we have more problems, the tree would have a shape that resembles a reversed cone (base on ground and vertex upside). Wood is light but also weaker than iron, so the height maximum reachable (to avoid mechanical breaking of the tree) should be slightly above or below the highest buillding, so don't expect it to be higher than a kilometer, however you could partially cheat if the tree grows on the highest mountain in your world. EDIT: since tag advocates are becoming increasingly boring, here's for the hard-science part: **Symbiosys:** no know micro-organisms have such a behaviour, however there's a spider that is able [to transfer air bubbles](https://en.wikipedia.org/wiki/Diving_bell_spider) below water level to create a nest. Since there are already life forms that move air somewhere, it is plausible to assume are possible life forms that move water somewhere. Also, snails have a protective coating to avoid dehydratation when sleeping, the tree and its life forms could use a similiar mechanism to preserve water. **Regarding the refrigeration:** simple physics law, if air do any work it spends energy in doing so and hence lower its temperature, [also certain shapes](https://en.wikipedia.org/wiki/Pelton_wheel) (double "U") are really helpfull in draining thermal energy and converting it in kinetic energy Since a big life form is highgly susceptible to die by any disease (single DNA), it is more realistic if the tree is in reality a composite life form so that it has enough DNA variety to not die entirely due to diseases. We have already proofs of this being possible (moss is in reality made by 2 different life forms cooperating), also it is possible to do vegetable grafting (put a plant branch to a foreign plant to obtain new type of fruits), another proof that a vegetable life form wich is in reality made by different life forms is entirely possible. [Answer] **This question asks for hard science.** All answers to this question should be backed up by equations, empirical evidence, scientific papers, other citations, etc. Answers that do not satisfy this requirement might be removed. See [the tag description](/tags/hard-science/info) for more information. Wind is a killer. There is a reason that the tallest trees have few branches below their crown. Catchment basins would act like sails and tear the tree apart. Sorry to rain on your parade. The highest building in the world is 830 meters tall and I doubt that mother nature could do more than double that with a living organism, but I'm just guessing... [Answer] **This question asks for hard science.** All answers to this question should be backed up by equations, empirical evidence, scientific papers, other citations, etc. Answers that do not satisfy this requirement might be removed. See [the tag description](/tags/hard-science/info) for more information. Just passing through and thought I'd leave my thoughts on this topic... Have a look at the latest (last) book in Terry Pratchett and Steven Baxter's Long Earth series, "The Long Cosmos". One of the worlds there has ginormous trees. Water transpiration to the upper branches is effected by the trees capturing / generating hydrogen, and using this to float sacs of water up to the upper levels. Of course, the wood of the trees were highly imflammable, being chock-a-block full of hydrogen. The existence of such a world and such curious trees was never reported, probably because any traveller who stepped in, and stayed long enough to note the size of the trees, probably stayed long enough to collect some wood and make a fire... BOOM! [Answer] **This question asks for hard science.** All answers to this question should be backed up by equations, empirical evidence, scientific papers, other citations, etc. Answers that do not satisfy this requirement might be removed. See [the tag description](/tags/hard-science/info) for more information. No. As trees are today it is impossible. In trees water is drawn up the tree passively. To get the kind of heights your looking for the tree would have to pump it own water. I can't see how a tree could produce enough energy through photosynthesis to power an active method of water transportation at that height. Furthermore if the tree grew too high the air would be too thin for photosynthesis or respiration. In order to survive our tree would have to eat other plants for sufficient energy and would have to pump oxygen up to the top of the tree. [Answer] **This question asks for hard science.** All answers to this question should be backed up by equations, empirical evidence, scientific papers, other citations, etc. Answers that do not satisfy this requirement might be removed. See [the tag description](/tags/hard-science/info) for more information. A smaller version is possible, especially if it is adapted for that sort of thing: It can have a very thick base and thinner at the top (so it won't break), and very long roots that are spread out (so it will get minerals). If it is near a river, in a relatively windless area then it can grow to large heights. This solves the problem of nutrition (the waste in the water provides nutrition, as well the other stuff stated by [KingOfSnakes](https://worldbuilding.stackexchange.com/questions/48435/would-a-world-tree-be-feasible-in-real-life/48450#48450) and it can have a heart which provides additional pressure to draw the water to its leaves. [Answer] **This question asks for hard science.** All answers to this question should be backed up by equations, empirical evidence, scientific papers, other citations, etc. Answers that do not satisfy this requirement might be removed. See [the tag description](/tags/hard-science/info) for more information. It depends on your definition of "tree". First, there are multiple answers here that propose a heart--this doesn't overcome the problem that lifting the water costs more energy than the photosynthesis yields. This means either we obtain the needed water directly from the atmosphere (which means a humid climate) or we need some radically different chemistry. Since we want something tree-like lets start with photosynthesis--but the high energy molecules aren't sent down the tree, but only laterally to the trunk where they are converted to electricity. The products are sent back out to the leaves to be combined again--you only need to lift for growth or leakage, not for energy production. Now, we need a very strong tree--instead of wood lets figure a core of metal foam. Once the roots find suitable ore deposits they grow a metal foam core in each trunk. For the sake of strength you need multiple trunks with many cross connections. Look at how antenna towers are built for how the tree has to do it. As the tree gets big enough we can take some of the load off it. The tree grows a transparent but airtight canopy over itself. The leaves are inside this canopy. The canopy acts like a greenhouse--the insides are warmer than the ambient air which is good as it gets cold up there and you have in effect a giant hot air balloon. If it's big enough the only elements in compression are those holding out the waist of the bubble, the rest of it is all in tension and therefore much easier to support. The tree needs to have full regeneration capability or else the ravages of time will kill it before it gets to the size of a world tree. [Answer] **This question asks for hard science.** All answers to this question should be backed up by equations, empirical evidence, scientific papers, other citations, etc. Answers that do not satisfy this requirement might be removed. See [the tag description](/tags/hard-science/info) for more information. I can think of a few options, some of which will just be additional notes on existing answers: **1. Capillary Action** Capillary action could possibly circumvent gravity - it already does on a small scale in all sorts of real world situations. The basis for capillary action is surface properties and surface tension of fluids allowing them to rise (or fall) through extremely narrow channels. A fountain pen is a great example of this. If you take an empty fountain pen and rest the nib in an ink well, ink will slowly rise through the nib into the ink feed. **2. Water Collection Basins** A tree could have natural collection basins, akin to a [strawberry pot](http://2.bp.blogspot.com/-RV5HmQFZWMs/TbTGRbqd7iI/AAAAAAAABLY/_ez9RQR4LX4/s1600/strawberry_pot.jpg). This would allow the tree to naturally collect reserves of water anywhere along its surface. This could even be done (through some twist of evolution) at each location where a branch meets the trunk. Actually, I'm almost surprised there are no Earthly trees (as far as I know) that do this. Or possibly it's leaves could be designed to funnel water into such a system. [Hostas](http://thumb9.shutterstock.com/display_pic_with_logo/351577/318651596/stock-photo-wet-yellow-and-white-hosta-plant-with-waterdrops-in-garden-318651596.jpg) work like this on a much smaller scale - drawing water into the base of the plant. **3. Atmosphere** If your planet is not strictly Earth-like, and the tree is tall enough, a persistent or near-persistent vapor base (clouds) at or near the crown of the tree could provide ample water, especially if the tree had adapted structures that would help capture and channel water. This could even be as simple as interestingly channeled bark-like structures trapping and condensing water from the vapor. [Answer] **This question asks for hard science.** All answers to this question should be backed up by equations, empirical evidence, scientific papers, other citations, etc. Answers that do not satisfy this requirement might be removed. See [the tag description](/tags/hard-science/info) for more information. All other answers assume the tree is growing in a gravity well. This need not be the case - however, other constraints will apply (read Niven's 'The Integral Trees'). There is also a question of scale. A perfectly normal tree could be considered a 'world tree' by a *very very small* intelligent race. [Answer] **This question asks for hard science.** All answers to this question should be backed up by equations, empirical evidence, scientific papers, other citations, etc. Answers that do not satisfy this requirement might be removed. See [the tag description](/tags/hard-science/info) for more information. The tree could get "help" from other organisms, willy nilly. People could feed it (they'd need a motive). Or it could consume other plants. Then it could have access to more energy and different materials than a normal tree. I highly recommend that you read the novella *The Son of the Tree* by Jack Vance. It also has a world tree. Its feeding patterns may be...instructive. It could also do something with solar power in order to generate energy, either by heating water in basins through reflective leaves, or by using metals that catch light and convert it into electrical power. It may be far-fetched, but it could work in a novel. --- Another idea is that the world tree could get it's nutrients from the waste products of animals that live on it. [Answer] **This question asks for hard science.** All answers to this question should be backed up by equations, empirical evidence, scientific papers, other citations, etc. Answers that do not satisfy this requirement might be removed. See [the tag description](/tags/hard-science/info) for more information. I believe that in order to make the tree possible the tree would have to be constructed with genetically modified tissue vertically with an ascending team of 3D printers as if a spider wove its cloth upwards, and this would have as main objective to have a "living" To shelter human life like living in a biological skyscraper, I believe that with all current and future technologies and the most brilliant minds in engineering and design it would be possible to build a tree that could reach 40,000 feet, ok no :P. [Answer] **This question asks for hard science.** All answers to this question should be backed up by equations, empirical evidence, scientific papers, other citations, etc. Answers that do not satisfy this requirement might be removed. See [the tag description](/tags/hard-science/info) for more information. Lets say world trees really could have existed on earth it would need immense water to sustain itself i think of natural pure and warm spring water under it that flows up under higher pressure created under ground aiding the tree to pump the water up higher into its self and to prevent it from crushing into its own weight parts of its stem/trunk and root system must have been crystallized by the pressure of its weight together with the minerals within the spring water as it grew over time (like some of that evidence is found in tree stumps/trunks on this site <https://secretenergy.com/news/are-these-giant-prehistoric-trees/>) [Answer] After looking at all of the comments, this is my personal conclusion for the ultimate "world tree". **Leaves with very short hairs.** These leaves would not only produce energy through photosynthesis but absorb water like roots, where the hairs act as root hairs. With slightly different physiology this is certainly possible. **Location in a valley providing relative shelter from winds.** The tree would also be very thick at the bottom and get progressively thinner to avoid breaking. **No more than 2000 meters (2 km) high to avoid constant, ultra-low temperatures, but still have a massive size.** This would also remove the need to make ridiculously strong wood or other, more complicated and/or unrealistic elements. **Light but relatively strong wood.** The tree would also (as with most plants) have a high lignin content, from which it would somehow produce its own carbon fibre and implement it into its own structure in high quantities, greatly strengthening the tree to keep it from essentially imploding. **Pools of water from interlocking branches and/or leaves above ground-level, drawing in critters and providing energy reserves if needs be.** Microbes, insects, small mammals, and other organisms would be attracted to the relative safety/shelter of the tree, and with water, they would be even more likely to wish to take up refuge there. They could provide minerals and other nutrients in the form of their waste, and could even form a stronger symbiotic relationship of some kind (use your imagination). The pools would also work as energy stores, where the water could be saved and then used by the water-absorbent leaves. **Very thin channels in the tree.** Water and other nutrients could travel throughout the tree based simply on the behaviour of fluids in very small channels (see Jesse Williams’ response for a somewhat more detailed description). **Large root system capable of bringing other nutrients and support/stability.** **Multiple "trunks" winding together.** This would divvy out the trees own pressure more evenly, among other things. [Answer] In my opinion, a world tree would be impossible to make if the trunk is only composed of one part. But if we take into consideration some trees like the [Banyan](https://www.google.com/search?q=banyan%20tree&rlz=1C1CHZL_enIN837IN837&source=lnms&tbm=isch&sa=X&ved=0ahUKEwi6u5vKv97iAhWUbX0KHSn-Dh0Q_AUIECgB&biw=1280&bih=610#imgrc=DlklxY-9kyg2CM:), or much more known in our country as *balete*, I think it could grow to become a world tree, provided that it has sufficient nutrients to support it. A banyan tree is really a small tree if it is alone. However, it makes multiple aerial roots. And these roots grow big until it becomes like it's mother trunk. Its aerial root system made it possible for it to become bigger and bigger without fearing of being toppled down by gravity. So, that's it. If our world tree has multiple aerial roots, it can support itself and not fear the ferocious hand of gravity. And it will grow taller and taller, but it will expand more and more, taking up more space than we would like it to be. ]

[Question] [ In *The Walking Dead*, the survivors have seen plenty a wall. From Woodsbury, to Wellington, to Alexandrea, they are all different and they all have their advantages. One issue that none of them have managed to fulfill yet is the gate though. Every wall in the walking dead, and in history, has one major weakness, the gate. No matter how strong the wall is, the entrance to that wall is weak. Take for example, Alexandria. Their wall is made of large metal plates held together with steel supports and mound of dirt behind them displaced from a frontal moat. While this wall is successful at repelling any threat, when thousands of zombies came knocking at their door, the door fell off its hinges and the wall became useless. This made me realize that the gate is the primary weakness of all walls and also made me wonder; is there a gate design that can repel hundreds, if not thousands of zombies, while still allowing humans to enter? [Answer] We humans are pretty good at building gates to keep people out. We've been doing it for a long time for military purposes and to stop thieves. # Why Do We Have Gates? Because there has to be some way for friendlies to get through the defenses while keeping the bad guys out. From a military perspective, a gate isn't there to stop people from getting in. They'll get in. Instead, it's there to channel them into a particular area by the allure of an easier passage. Avoid the wall and its defenses, drive through the gate! In anticipation, that particular area is set up as a kill zone: a deadly crossfire will be in place to mow down anyone who comes through, combined with removable obstacles to slow them down and pin them in the kill zone. From a security perspective, a gate is also there to slow down a thief. But instead of a kill zone, it exists to be such a nuisance to force the thief to give up, or to make so much noise getting through they're detected. Once detected, forces are rushed in. So, gates exist to... * provide access through defenses for friendlies * herd attackers into a kill zone * force the attacker to reveal themselves * slow the attacker to there's more time to deal with them Zombies don't act like an intelligent, coordinated military force, nor do they act like thieves. They just walk, slowly, towards food. They might not even find the gate and instead just walk into the wall in whatever direction they came from. (Note: I only watched the first few episodes of The Walking Dead, so I don't know exactly how their zombies act). That is until you start making a bunch of noise going in and out of the gate. Then they'll go investigate. The problem is not having a big rush of zombies at the gate, the problem is having a slowly growing, constant pile up at the gate which is putting more and more pressure on it until, like a fence at a football riot, it will collapse. Zombies also don't get tired and give up. They'll keep banging on that gate and walls until one of them breaks. This means you need an active defense to clear the zombies off, and you need to do it efficiently and safely. # Establish A Kill Zone Take advantage of that pile up and use it as a kill zone. The zombies will be easy pickings as they pile up against the gate, or even the walls. A few isn't a problem, unless you need to go out. Take care of them before there's too many. # Kill Them Cheaply You want to set up your gate and defenses so the zombies can be killed without expending resources. This means no guns and no gasoline. There's going to be a lot of them, and you only have so many bullets. Save them for emergencies and foraging. # Kill Them Safely You're going to be doing this *a lot* and even a single bite means you're dead. That means it has to be done very safely, no heroics. # Bars + Pikes The simplest actively defended anti-zombie gate is some sturdy iron bars and a few people with pikes. Zombies thrash against the iron bars, the pikemen stick them in the face from well outside of arms reach. Cover the end of the shaft in grease to prevent the zombies from grabbing it. If they do, pikes are cheap. Let go and grab another one. Maybe you can get the lost one later when they're all dead. These bars can and should be placed all around your defenses to prevent zombies from piling up at any point on the wall. # Flexible Gates Against an enemy like a zombie, rigid defenses might not be the best idea. Instead, you might want to try a [flexible security gate] like you'd find in a mall. [](https://i.stack.imgur.com/gRPCw.jpg) Unlike rigid bars which will take all the force of zombies banging on it, a flexible security gate will flex and wobble which will absorb some of the impact. And they have those handy slots for stabbing zombies through. Just make sure it's strong enough to hold back a horde pressing against it, and it's secured to something that's strong enough, too. # Evolution 1: The Murder Hole This is, essentially, an inner and outer [portcullis](https://en.wikipedia.org/wiki/Portcullis): a big, heavy gate with spikes on the bottom that drops from a height. [](https://i.stack.imgur.com/3Poo7.jpg) Zombies on the outside, pikemen on the inside. ``` =============== P * *ZZZZ P * *ZZZZ P * *ZZZZ P * *ZZZZ P * *ZZZZ =============== ``` Raise the outer gate, let some Zed in, then lower it again. If there's some zombies under it, so much the better. ``` =============== P *Z *ZZZ P *Z *ZZZ P *Z *ZZZ P *Z *ZZZ P *Z *ZZZ =============== ``` Now you can better manage the number of zombies you're dealing with at once. Once you're done, you can get into the inner area to clean the bodies up and avoid a pile up. There's any number of improvements which could be made to this, for example a grilled platform on top, out of arm's reach, to stab down through. Should the inner gate fall, you only have to deal with a limited number of zombies inside the wall. Should the outer gate fail, you have an inner gate to fall back to. This brings us to our next point. # Have A Mobile Backup Gate Taking a page from [The Road Warrior](https://www.youtube.com/watch?v=wNzfgl_H5vA#t=4m09s), use a heavy vehicle like a bus as a mobile gate. But instead of using it as your primary gate, have it ready as a mobile backup gate to close any breeches in the wall. Just drive it up to block the gap. This will plug the breech and give the defenders time to react. # Evolution 2: Dig A Pit, Fill It With Spikes If the Walking Dead zombies are like the Romero and Max Brooks zombies, they aren't very bright and will happily walk off a cliff if there's food on the other side. To make our murder hole even safer, we can add a pit filled with spikes. ``` =============== P *..............*ZZZZ P *..............*ZZZZ P *..............*ZZZZ P *..............*ZZZZ P *..............*ZZZZ =============== ``` Raise the outer gate, zombies fall into the pit and get impaled. It probably won't kill them, but it will immobilize them. Then stab them with pikes at your leisure. You can even throw a grating over the top to make the stabbing even easier. # Evolution 3: The Crushinator You've got these zombies pressed up against your gate, you know where they're going to be, why not use it to your advantage? Scrape them off the gate with a heavy object. ``` | O| -------|v | | | |Z =================== ``` You have a heavy door (optionally sharp) held above and just outside the gate. Zombies press against the outer gate. Drop the door right on their heads. Crush the zombies. Lift it again. Repeat until all zombies are dead or disabled. Finish them off with pikes. Safe. Efficient. And it's a spare gate! # Don't Have A Gate Taking another page from the original *Dawn Of The Dead*, do you really need a gate? What about a ladder or ramp? Zombie attack? Retract the ladder. Just be sure you have a way of clearing the zombies off the entrance, like a set of bars to stab them through. ``` ========= | ^ | O | - O _(Brains) |-o - o-| | | | | /\ | | /\ ``` # Try Things Out In [*7 Days To Die*](http://7daystodie.gamepedia.com/7_Days_to_Die_Wiki) *7 Days To Die* is a "survival, horde, crafting game". It's Minecraft meets Left4Dead. It's a great place to try out various anti-zombie defense schemes. What sets 7D2D apart from other zombie survival games is *everything is destructible*. Wood, metal, concrete, *even the ground itself*, the zombies will chew through it all. Any passive defense will eventually be ground down and fail. I've had zombies chew through concrete, wriggle through firing ports, climb over each other like ants, tear the foundations out of platforms, and even come up through the floor! The other thing that sets 7D2D apart is right in the title: every 7 days, ready or not, you *will* be attacked by a horde. It lends a certain time pressure to everything you do. Grand plans give way to necessity. Are you going to try to explore to find the mixings for concrete and bullets? Or chop down more trees to bodge together more spikes and arrows? Finally, while basic combat is rather simple, getting hit is brutal. Especially at the higher difficulty levels, one hit and you're stunned, two or three and you're dead. The game is still in early access, but it's totally playable and totally brutal. Big changes are coming in Alpha 16 in March, so you might want to wait until then. But if you want to torture test your ideas about zombie defenses, give it a shot. Here's the aftermath of a horde night in my fortified chateau. It took the "no gate" philosophy. All stairs were torn out, even interior stairs, and replaced with ladders and armored hatches. We attracted them to a particularly well fortified corner of the house. [](https://i.stack.imgur.com/f4qaN.jpg) That *was* four layers of spikes. Note the firing ports for an active defense. Also note the hasty repairs on the concrete; they got through, but that was just the outer defenses. We had multiple backups to retreat to. This was just one evolution of the defenses. [Answer] Human engineering can, 100%, keep out a horde of zombies. In *The Walking Dead* things fail because if they didn't the show would be boring. In real life, there exist castle gates hundreds of years old which would hold, no questions asked. First and foremost, realize that thousands of zombies will never be pushing on the gate all at the same time. They will spread out against the wall as the pressure mounts from behind. Thus, the gate doesn't need to be nearly as strong as you'd think. Second, take a pro tip from me, and don't build your gate on wheels, or out of chain link fence, as is the case in most walking dead situations. A draw bridge can be built. A portcullis, perhaps. These things are not rocket science, and will work much better than half the crap you see on that show. Bracing the gate would also be a good idea. Move a bus against it, or drive large stakes into the ground at intervals. Check out the siege scene in LOTR when helm's deep is being assaulted. Watch the soldiers barricade the gate. Now *that's* an attempt at keeping the enemy out, not the half baked efforts in TWD (if they weren't constantly being defeated and driven out of their "fortresses" the show would have been over in Season 3). Since you're asking for a design of a gate, here's mine: A gate you push into place from the side - large metal one (but not too long, as the longer it is, the more difficult it becomes to brace it). I'm thinking steel plates welded onto a nice, thick frame. Because you don't just want it to get pushed over, you need to secure it very well at both ends. However, that might not prove sufficient in a "million zombie horde" situation. You have to have the option of bracing it from the inside such that it doesn't buckle inward, and come free of one of the end points (and in order to keep some pressure off the end-points). Have stake pits dug, and brace the gate both with those, as well as with heavy beams. And if you *really* want to survive, have the option of lowering a plow -like device over the front of it. Imagine a giant horde coming your way. You seal the gate, put in the stakes brace it, and then swing a big metal "V" down over the side, such that zombies coming up against the gate simply push each other to the side, and into the walls. Future survivors will come across your fortress years later, see the tall, proud gate still standing firm, and think: > > "Wow, that sure is a great gate. Too bad they didn't build the walls as strong!" > > > [Answer] Use the power of physics, dirt, and the stupidity of zombies. Zombies break a door by exerting force against it *en masse*, but the zombies have to have an equal and opposite source resistance to push off from. Therefore, you give them extremely limited terrain to push off against the gate and then give the main horde something insanely difficult to deal with, like 15 tons of packed dirt with a concrete shell. Do something like this: ``` _|__(<-- gate) /// \ (horde) /// (solid stuff) \ zzzzzz___/// \(me, safe and sound) ``` It doesn't matter how big the horde is - they'll never break a gate that's situated like that, since the horde isn't capable of putting more than a few zombies in position to actually put pressure on the gate. It **is** possible that the zombies could dig through, assuming you just have dirt and given enough time, so you could either commit to clearing them out occasionally or use at least an outer shell of concrete or something. The zombie blood should make it impossible for plants to grow (too alkaline,) so you won't even have to worry much about plants weakening your concrete. Now, you may be wondering how this is different than a regular moat, as has been suggested in several answers. The key difference is that is takes an astronomically huge number of zombies to fill this 'moat', provided that you make the solid section steep enough to prevent the zombies from stacking on each other with the ability to push against each other. Your 'moat' is either the entire valley (if you're in a valley) or the entire planet below your elevation (if you're not in a valley.) Now that's, one heckuva moat. Finally, I realize that this isn't really putting much effort/thought into the gate itself, but (as in many things,) *it's all about location, location, location.* [Answer] As Andrei has already pointed out, if the doors didn't fail, there wouldn't be much of a series. However there are many imaginative ways to deal with zombie hordes if you have time to prepare. Here are a few. # Why have a door? Just have a solid wall all the way round and a ladder. Zombies aren't known for their intelligence, when under attack remove the ladder, there's no door to fail. # I really want a door though Interlocking doors that only open outwards. Vault doors are designed as a conical section, they will only open outwards, the more you push the tighter they fit. If you want a pair of doors, then overlapping panels such that again, the door only opens outwards. Like these lids, but bigger: [](https://i.stack.imgur.com/cxJ9X.jpg) # That's all very well but, I'm a horrible person What you need is a sharpened portcullis. The pressure from the zombies behind push the ones at the front through what is effectively a large scale potato chip maker (french fry cutter). You don't even need to kill them yourself, just have a pit for the bits of zombie to land in. Severing the head is irrelevant on a neatly cubed zombie. [](https://i.stack.imgur.com/wLfVC.jpg) You may want a blade you can drop down the outside to clear away the buildup of bits of zombie on the cutting edge. # As a final note on this [](https://i.stack.imgur.com/l0WKU.jpg) [Answer] # Don't let them even touch your door. You have your nice tall walls, you also have your nice gate behind a drawbridge and moat. [](https://i.stack.imgur.com/iXbXt.jpg) But this is a horde of the living dead we're talking about! Moats can end up filled with the writhing mass of the living dead who can eventually climb over each other to scale your wall or batter down your door. Water doesn't cut it. # The solution. [](https://i.stack.imgur.com/PuGVZ.jpg) Bellow and in front of your door you place a rock crusher salvaged from a quarry. You set up your fortifications next to a large fast flowing river to provide power for your crusher. The zombie mulch can also be ejected into the fast-flowing river to make sure you don't end up with a pile of rotting zombie flesh. This keeps the population of zombies around you walls low: Zombies are attracted by the sound of the crusher and any who stray into the crusher get pulped. When you want to let humans in you lower your drawbridge to make a path over the crusher. [Answer] From an engineering perspective (and having done mechanical engineering for better than 30-years, with a few college degrees for the trouble), I can say that the problem with doors (in reality) isn't that they fail, per-se, but that their attachment points usually fail. The 'threshhold' (door frame, hinges, latching hardware, and subsequent structure framing) are actually what fail most of the time, when dealing with real-world 'doors on old buildings'. Add to this problem the issue of a mob-horde pushing en-masse into the door, and you have a 'maximum material condition' best addressed by material properties considering age. To bring this down to a layperson's perspective, a 2-inch thick oak door, itself, isn't going to fail an interior hatchway (where water or weather aren't a significant aging factor). Failure will come from mechanical stresses (aging, fracturing, etc.) of the mounting hardware (all iron-based metals fracture, in-time). Were I building a 'thousand-year-zombie-door' (in absolute theory, here), I would start with a granite double wall set up for a pocket-door (where the door slides, but not as a sliding glass door does - a pocket door is 'hidden' in a wall, when opened via being slid back). I would ensure that the header and footer track were at LEAST 15-percent the height of the passageway itself (so the door would need to be 30-percent taller than the opening itself, as it would also need to be at LEAST 30-percent wider). I would use brass or stone rollers on the top rail, and a secondary grooved channel rail at the bottom (to allow for drainage and prevention of the door galling into an immovable state over time). For the door material itself, I would most-likely go with either 45-55 mm thick stainless steel or high-phosphor bronze plate (so the door would most-likely weight a couple of tons). This would then provide for thousands and thousands of kilograms of resistive force for centuries, without reaching material failure points. It also allows you to still slide the door open with thousands of zombies on the other side, otherwise blocking you from opening it later, when you want to get out. Remember one thing, as they pile in, and block the door, they are also still 'juicy' and will rot an organic door and jam any fragile hinge, latch or roller mechanism. No jewelry box doors here, think more like aztec pyramid construction methods instead. You now have a worthwhile fort door that can be opened with a simple pry lever, at worst, that will last a millennium, and still look good being a 'door'. Oh, and you might want to remember a simple rule of combat: Make a fortress too hard to get into, and you'll build the perfect crypt you can't get out of! [Answer] Sure there is, it's been done already. A lot. Much field-testing has been done on the best way to break through a large door, especially when considering that the defenders will likely not be pleased that it's happening, although the tests were performed a while ago - a few thousand years ago, to be exact, when castles were still in fashion and a rival lord's raiding of it not out of the question. The solution for the attacker was a large battering ram, or to skip attacking the door entirely and just demolish the castle with siege weapons. Zombies do not have the capability to carry a battering ram, however, nor operate siege weapons. And those rams were only meant to bash through wooden doors. Doors of stone or even metal would be damn near impenetrable to human - or zombie - strength. As to why it didn't work on the show...well, it's on TV, and I blame the fact that the writers just wanted ~~DRAMA~~ and cared more about that than physics. [Answer] Something to keep in mind: Zombies can't develop any huge pressure against the door. Their bodies aren't able to take infinite pressure, if enough of them are trying to get through your door the ones in front will be crushed and cease to be able to provide pressure. Thus sufficient zombies means that the pressure actually is reduced, not increased. Besides that, there's a simple way to build an entryway that will stop a horde of zombies. You need a moat, ideally with a river flowing through it. Unlike a normal castle you want the moat inside your walls. Build your outer wall to funnel the zombies into your gates. Your gates extend across the moat except the floor is actually hinged to the bottom of one wall and counterweighted with 300# more than needed to balance. **A** person **walks** across them, no problem. The walk up to the door, slide it to the side and enter. The walls and door are tough enough to take a few zombies. Once 300# of zombies accumulate in the corridor the floor tips and they're dropped into the moat. Obstacles are arranged to ensure they die on the way down. Then the floor rotates back into position and more zombies advance to their death. If you have a river in your moat the corpses go off to sea rather than pile up underneath (a sufficient pile would jam the door.) [Answer] I don't know if a gate can stand the force of hundreds of (undead) humans, but there **is** indeed at least one way of making the gate *almost* as strong as the walls around it. **a- Use a sliding/rolling gate instead of hinged design** The gate slides up and down in the wall. Its edges are 3 feet inside the wall at both ends. There are no hinges anywhere, just ball bearings, wheels and a high friction surface (of the walls) for the wheels to roll on. **b- Use a few long, thick spikes on the gate** This will help hinder the zombies from pushing at the door altogether. Considering that the zombie who tried to push in, gets spiked and unable to move, it will be very hard for the zombies behind that first zombie to shove him aside and make their way forward. [Answer] A gate that comes down from above. For example, stairs that fold out from the side of an aeroplane or a rope ladder lowered from a kid's treehouse. Zombies are dumb. They won't climb, just mill around. Build a wall with no gaps, and have a crane raising and lowering a large platform, big enough to fit a truck. You could make some noise on one side, attracting all the zombies to that part of the wall, and then drive the crane to the other side of the compound and its platform without having to worry about zombies piling on. [Answer] ## A door which can only open outwards, on rails. The architectural design is below (as seen from the top): [](https://i.stack.imgur.com/hOUx7.png) The black part is the wall. The gray part is the "door", made of the same material as the wall. If you want to open the door you must slide it on the blue rails outwards. When zombies arrive, they could * try to push the door, which will then push against the walls, effectively becoming part of the wall. They will not get in. * (assuming some intelligence) realize that the door moves outwards and try to pull out. The red part comes then into play: it is solidly attached to the door and turns horizontally to push against the walls (when one wants to prevent the door to be open (=pulled outside)) or vertically in normal times. There could be other designs here, the point is to make sure that one cannot pull the door out from outside (a hinge could be a better choice) [Answer] Worried about many zombies being at your gate and it weakening over time due to too many zombies pushing on it. You need to keep them split up. Barriers are used for this exact purpose during festivals, the idea is to limit the amount of pressure on the front of the ~~crowd~~ zombies. For example: [](https://i.stack.imgur.com/MbUjh.jpg) The zombies are kept back from the main stage using barriers, there is another set just out the camera view preventing crush events. Using this we can lower the pressure on the gate, so the gate doesn't need to be as massively built. Spiting them up can make it easier for the other methods to deal with the zombies. Combined with other methods this can be effective as well. [Answer] Don't discount the moat/drawbridge. If the moat is right up against the plane of the gate, it will have the following effect. The shambling dead come, fall in the moat, more of them come and fall in eventually filling it up. Here is the thing, piles of squirming, hungry ghouls will not make for good enough footing for the remainder to be able to generate tons of pressure against the gate. In addition, a gate with two doors, that is well anchored against a solid wall, can be built to swing out when open and when closed the 2 sides will overlap and lock in place, with any pressure binding it more solidly against the framework. I'm trying to work in ChaosCenturian's Zombie cheese cutter as well, but not having a great amount of luck. Always remember to sever the head! good luck [Answer] You can build an indestructible wall or gate; at least, indestructible by meat. The real problem is dealing with (say) 30 million corpses as the infinite wave of zombies crush against your base and die, forming a ramp of crushed flesh which the next wave crawls over. A 100 kg corpse with the density of water has a volume of 100 L. 30 million of them comes to 3 million cubic meters. Assuming a cone with a 10% gradient to the pile of zombies, the volume of a cone is $\pi r^2 \frac{h}{3}$. A 10% gradient means $r = 10h$, giving us $3000000 m^3 = \pi \frac{100}{3} h^3$ which is roughly 30 meters. Now, a half-cone has half that volume, so to build a fortress capable of surviving 5% of North America's entire zombie population smashing against it and forming a human ramp, you need walls (and doors) that are roughly 30 meters tall, and the wall needs to be able to support a huge mass of zombies (roughly equivalent to water) on the other side. 30 meters of water generates about 3 atmospheres of pressure on the base of the wall, or 30 tonnes of pressure per square meter. 30 meters is about 4 stories. The wall height needs to be tweaked based off of zombie pile slope and percent of continental population of zombies we have to survive. The compressive strength of any reasonably built concrete is well beyond this; but any jury-rigged walls or doors are going to fail. The door itself is a relatively small problem. Arrange it so that you cannot get a "run up" on the door by having the wall "wrap around" the entrance area with a choke point. Have multiple doors; I would go with 3, with only 1 every open at a time. An attack overwealming the outer door (a bomb by humans, or the door is accidentally unlocked) leaves at least 1 door sealed. This follows the rules that you have a never event (zombies getting in), you need for an unprecidented failure to *still* leave you with a layer of safety. Outer door fails while an inner door is open; no problem. Only lose people within the killing zone. ``` ************************ * # * KZ3 # Inside * # * # *******######*********************************************** * # * KZ2 # KZ1 Outside * # * # **************************************** ``` Here is a gate designed to surive against zombies. We have an outer wall that prevents "direct charge" of any of the doors. Kill Zone 1 is an isolated area where zombies breaking in can be slaughtered from above/through holes in walls. If there are "low" places to fight from KZ1, access is via ladder into KZ1; you cannot flee from KZ1 out of it directly until zombies in KZ1 are dead. The ability to "drop down" into KZ1 from the 30 meter (or however tall) walls above is possible, but this should *never* be deployed, and any drop-down should be from KZ2. KZ2 and KZ3 works similarly, but it is behind the door of `#`, and are isolated from the safe inside by another door of `#`. One-way entry to the "killing locations" in KZ2 can be reached from KZ3, and KZ3 has "one way entry" to the killing locations from the inside. The "killing locations" are things like raised platforms or iron-bar fortified ground locations that you can use pikes to fight from. These are used to clear the killing zones if besieged. These killing locations are not presumed safe from being overrun. Doors should be things like thick metal bars with thin gaps lowered from above. Simply too massive to be dislodged by mere meat, and mere meat cannot stop them from lowering. Wooden doors that can be closed to block line of sight can be added, but are not a requirement for the barrier to work. Killing zombies through these doors should be possible. Someone getting a truck and smashing the outer gate while the second gate is open is the "worst case" this is designed to defend from. Cinematic failure would consist of the people in killing zone 3 "killing location" fleeing, convincing people outside of it to lower rope ladders or somesuch, then being overrun and zombies getting inside. So the next stage is dealing with exactly that; KS3's "one way" entrance needs to be "airlocked" in a way that doesn't permit local zombie infection from getting out. [Answer] I'm thinking of a beefed up revolving door, the type you see at the mall to lock the air temperature in. Then build a mechanism, an additional blockage on the inside, that can either open inward, or seal the way in. So to open for friendlies we can keep the channel open through. Humans can push the door half a cirle and walk in like normal. Comes a zombie and we close the plate inside to block the passage, and he can spin the door the whole circle just to end up right back outside, wondering in a zombie way what is going on... And better yet, build that whole gate as a turbine. Make some noise to invite thousands of them to come and spin the gate to generate some electricity for us... [](https://i.stack.imgur.com/zaEs7.jpg) [Answer] From a purely defensive viewpoint, the best possible design for a gate or door is the same design that many bank vaults use. You take a heavy metal door which is smaller on the inside than the outside, like a ziggurat on its side, then put it in a matching door frame. The larger portion of the door prevents the door from pushing inward past the frame. Combine this with heavy hinges and pistons which slide out of the door into the frame, and you have a virtually unbreakable door. This same basic principle is used in many military installations, such as the famous "red door" of the Cheyenne Mountain Complex in Colorado. In fact, the design is often called a "blast door" because it can withstand MASSIVE amounts of pressure from the outside. The weight of the door itself isn't really an issue, either - as long as the door, hinges, and surrounding wall are strong enough to withstand the amount of pressure exerted against it, a door of this design will NEVER give or fail. [](https://i.stack.imgur.com/kFy30.jpg) Now, all that said... this is serious overkill for zombies. This door will hold even if the zombies are running into it with bulldozers at high speed, or ramming into it with tanker trucks full of gas, or even shooting low-yield nuclear weapons at it. And if they're doing all that, you're pretty much screwed anyway. Just accept your fate and die with some dignity. [Answer] **A Drawbridge**: Raised, say, 5m above the ground level of the rest of the wall, so that it opens on the second or third floor. The other side lands on a raised cantilever, like a viewing platform, at the end of a ramp. When raised, there is nothing connecting the two ends, so the the gate is inaccessible from the ground. When lowered, the bridge connects both ends and, depending on the material, you can drive heavy vehicles across. Since from the ground level there is nothing different about the gate area, compared to the rest of the wall, the *gate* is secure. ...unless you've got intelligent zombies who can look up.... [Answer] If your wall is so resistant that you only need to worry about the door, you can build something like this[](https://i.stack.imgur.com/Tu4bB.png) where `gray` is the wall and `blue` is the door. The zombies can't exert the force in the direction needed to break the door. [Answer] Simple. A trapdoor. It requires being lifted up thus any zombies trying to open would have to bend down and grasp the door assuming they had the intelligence to do so. Even if smart enough the number of zombies lifting is limited to the number of zombies that can reach the door at one time. If the trap door has no handles on the outside no zombies can even try to lift it. In all likelihood the zombies would shuffle across the top and not even pay attention to it [Answer] Any reasonably heavy metal door or hatch, that closes into a tight-fitting heavy metal doorframe with minimal protruding edges, and which is equipped with several reinforced bolts and hinges, should be easily resistant to zombies (unless the zombies can figure out saws, explosives, or particularly effective battering rams). (Think of the heavy metal lockers they have in campsites in bear country. Bears can rip into cars with their claws, because cars have windows and are made of thin sheet metal. These lockers are made of steel that is at a minimum 6mm thick, and reinforced.) To resist battering rams better, make it sloped, and also grease the outside of the door and the surrounding wall so that zombies have a hard time grabbing it. Also, as others have said, you're going to want to be able to shoot at the zombies attacking the door, defending it will make it much more resistant. If I had the required time and materials, I would make a hatch out of 12mm thick steel, tilted at a 45 degree angle, reinforced with welded metal on the back, opening upwards, and seating in a doorframe made of welded 12mm-thick-wall box channel beam or angle steel. The "hinge" would be a ~16mm dia or thicker steel pin. Counterweights would allow a human to open it. I can't imagine zombies defeating that; there's a limit to what brute force -- that still relies on human muscles -- can do. [Answer] As already pointed out, there are many ways from medieval times to build a zombie proof entrance. The problem is to build it. Remember, we don't talk about medieval times, when you had a lot of time to prepare for a coordinated attack every so many years. We are talking about building your defenses under the constant thread of uncoordinated and mostly small attacks. So you do not want to build a complex structure which requires you to live with a hole in your defense for months, weeks or even days. Even a few hours can proof fatal. We probably also want an entrance that is not by default open and can quickly be closed, like in medieval times, we want an entrance that is closed by default and can be quickly opened and closed to let people in. And, if possible cars and similar stuff too, but that would be a bonus not a necessity. So the sideways rolling entry from the series is a good start, since it can be placed quickly and fulfills all the requirements. And if you park a car against it, it can probably hold against a pretty big pileup. But you have the risk of someone forgetting to lock it. And if you kill the zombies, you have a big pile of corpses and no guaranty that you got all of them, so moving them per hand would always carry a little risk. So we use the protection of this gate to build a kind of portcullis. You'll have to build two big towerlike constructions as guiding rails, but you have some time. The grate itself should be heavy is best connected to some winding mechanism. This way it can not be raised by hand by a (human) attacker, but only from inside. This wind should be connected to a motor (a car could be modified for this) to raise the gate quickly. But there should still be a manual way to raise the gate, if you run out of gas or the the car breaks or something. Important is, that the gate lowers itself after a short time, if not attended to, so it can not be left open by accident. To accomlish this, the motor should only run while a button is pressed (or something similar, depends on the resources available and the specific way the motor was implemented in the construction) and the gate must not have a mechanism to arrest it in an open position (like the medieval ones did). The best position for the portcullis is directly behind the old gate, so we only lose a little space and can build it in the safety provided by the gate. After we constructed and tested the portcullis, we can deconstruct the old gate to save resources and speed up the process of opening up for incoming friends/allies. Now we are safe against forgetting to lock the door or the guard getting killed while the door is open. But there is still the problem with possible pile-ups and also there can be an attack of humans, who use for example a truck as a ram. The answer to this is a moat and a drawbridge. We need the bridge first, since we cannot pass the moat without it. The bridge itself can be prepared inside, but the hinges have to be build in place. Best position for this would be, where the old gate was. Before we install the bride, we also have to start some more complex constructions: counterweights. We want to lower *and* raise the bridge quickly and it should be massive enough, so (best case scenario) even trucks can pass it without problems. That means we have a pretty heavy construction. So we also need a stable construction with thick steel chains and girders, that is able to support the weight. This has to be constructed inside and put up in a short amount of time, since putting it up probably makes a lot of noise, thus attracting zombies. But after we build it, we can start digging a moat. We have to be careful while doing so, not to undermine our structures for the drawbridge (remember, that thing is **heavy**). The moat should be at least 2m (7 feet) deep, so the zombies can not climb out. Now, we have taken care of the pile-up problem and are save against attacks by ram-like constructions. Most zombies will fall into the moat and can be moistened with some oil or fuel and burned from a safe distance. A little smelly but save. And a well balanced bridge can be quickly lowered and raised by hand. Now there is only one thing left to do for a perfect defense: a second drawbridge. We construct a small island surrounded by a moat. One bridge connects it to the outside and one to the inside of out fortress. We sacrifice some space to do so, since the structure is probably to complex to be build outside the walls, be it will be worth it. Now, if someone approaches the fortress, we lower the outer bridge and raise the portcullis. They can enter the island, the portcullis is lowered and the bridge raised. If the approaching person or group is closely followed by zombies, we don't risk them getting inside. If the zombies were to close and catch the person/group, while entering, they still aren't inside the base and we can dispatch them from a distance (if they don't fall into the moat anyway). If the arrivals make it to the island without any zombies coming in, we can safely lower the inner bridge and let them in. Also, there is the possibility of people arriving, we don't know (or trust) yet. We can let them get on the island, thus granting them asylum and some safety from the zombies without actually letting them inside. Now we have an extremely safe gate and it would be a good time to expand the moat, so it reaches all around the fortress. The result reminds a lot of medieval castles, but there are small differences. Mainly that the default state is not, ready to be closed, but closed, ready to be opened and closed again. And we can use motorized mechanisms for the portcullis. ``` |o #|### # #| # # \-#| # \-# \#| # \# ***| |#***#| |#***** | |# #| |# |__| |__| ``` [Answer] A dumb idea or work around would be the trope of Razor floss. something like a super thin wire set into a door way such that as the pressure of the zombies mounted they just cut the front line in to bits. Your number 1 problem becoming dealing with body disposal. [Answer] How to build an Anti-Zombie door: 1. Go to store. 2. Buy a standard door. 3. Hang it on standard hinges as normal. 4. Close and lock door. 5. Congratulations, you've made an Anti-zombie door. Zombies wouldn't clump as they are shown, and enough pressure to break a door is not achieved by a zombie horde even if they did, and even if it were, the first few zombies would be crushed and block the path from zombies entering, and even if that were not the case they're all funneling into the same passage making them easy targets since they have to come in 1 at a time. [Answer] ## Redirect and mislead. Build an outer wall, with an obvious and noisily entry gate; the zombies enter it, and are led into a kill zone (one or several big holes, spikes at the bottom), with a dead end. They get nowhere near the inner wall's gate. Regular humans will enter/exit the outer wall by a concealed outer gate, not noticeable by the zombies (they're dumb). [Answer] Well I think a rather simple design might be to steal the idea of the Plow from above and simply make it the gate. So instead of a straight across/up gate make it some version of a V type gate. You can construct the braces with a beam/bar fitting into the door panel and the ground. Get adventurous and have a platform covering the opening at the top for easy pickings vs the Zombies. Get even more adventurous and have a walkway up there that will channel the zombies to the end were they fall (get pushed) out. Maybe put a grinder were they fall. Get even more adventurous and provide slots for pikes (as mentioned in another answer). Should be relatively easy to open and close. An attempt at drawing :) ``` ######## # # # # # # ### ### \/ ``` Pressuring the doors from the outside push's then together and the individual door can be braced. Platform on top of the V can be used to attack the zombies. Equaly any number of schemes for funneling the Zombies can be used here. Most notably would be steps up on both sides with a walk way away from the door to the outer edge which could simply be a drop to the ground, grinder, pit (hum Fire Pit?) etc. Regardless the spirit of this is to funnel the "horde" away from the gate in a constant flowing manner. The V gate has a very short space to open to full and close. [Answer] Several answers posted show gates that could survive any conceivable zombie attack. I wanted to mention the best defense would be one that stops the zombies before they ever reach the compound wall in the first place. My solution would be to build a secondary wall and audio trails to keep zombies away. We know from earlier Walking Dead episodes that zombies are attracted to sound and light. None of the towns really use sound or light decoys to direct zombies away from a compound because the show uses the zombie horde attack as a plot device. If this was a real life situation, building a secondary fence away from the compound would help direct the zombies to another location. If you build a series of audio devices along fence line, you create an audio trail to draw the zombies away from your compound area without directly interacting with them, saving you time and effort. This way zombies that are some distance away might be redirected and never approach your area in the first place. If they never enter your area, they never become a potential threat to your gate. [Answer] There is something that we know can take an awful lot of pressure. The breech of a cannon. Make the door in a short cannon barrel as a breech, preferably with a diameter so that you can have trucks driving through. You'll probably need a plate that can be pushed forward from the door to clear out zombies in the barrel. If fire destroys these zombies then a regular burst from a flamethrower from a hole in the top of the barrel followed by a push from the plate and the barrel is clean again. The zombies will have to move the wall because they are not going to move the door unless it is opened from the inside. [Answer] Since this is the walking dead zombies we're designing this wall against all we would need to do is direct sounds inside the wall away from the outside of the wall - this sounds dumb and hard, but I think it's doable when you consider how sound is already being directed away from places the user is likely to be in some gaming desktops - and tie de-toothed walkers to the front entrance. This way the walkers won't be able to hear the humans inside the wall and they won't be able to tell the difference between the wall and de-fanged walkers. The better question is why would you want to do this? none of the walls in the walking dead have ever failed because of walkers. They always fail because the people do something stupid in terms of maintenance with the wall. The little girl feeds the walkers rats at the prison and then someone drives a tank through the gate. The wall at Alexandria fell because someone didn't do anything about the building that could, and did, fall through the wall. The wall at the hilltop "broke" because humans on the outside broke it. These aren't things that repelling walkers from the gate is going to fix. If you want to fix this stuff then you should really just build bigger walls. Notice that no one has a secondary gate. No one has a second wall either. When you look at the walls in the walking dead they're just poorly designed for defensive purposes because they were put together in a rush to deal with walkers. All of the people with worse walls than the ones featured in the show currently have lost their settlements because the built garbage walls. Remember Noah's colony with the week 10ft wall? Compare that wall to the one at the hilltop. ]

[Question] [ Let's assume that humans can now run 40 mph and the human body can handle it. I know and understand that this is not feasible, but let's just play pretend. Naturally people would have all kinds of fun, but as we all know most people are wild, panicky idiots. I imagine that there would be millions of people who have accidents such as: * Head on (other head) collision * Not stopping in time for actual traffic * Running into walls **Some clarifications** 1. Humans suddenly gained this ability. 2. A fit human can keep up this speed for around an hour before they need a break. 3. Their reflexes do not change with their speed. Obviously this is a problem, as it's not a car but an ability the government can't just take away. So, what is the cheapest solution for keeping people alive in this scenario? [Answer] ### Enforce a 10 mph speed limit *I will answer from the point of view of the government, to minimize both casualties and costs.* Walking or running over a 10 mph speed limit is now a public offense, punishable by law, unless you get express permission from the government (example : the Army or the Police). This decision will be heavily broadcasted and communicated, so nobody can ignore it. It will be enforced as soon as it is broadcasted. Traffic radars will be reprogrammed to capture anyone trying to run over this speed limit, and the police will be able to give speeding tickets to anyone moving faster than the limit. The first time, the cop will give a 10 $ ticket. The second time, this will be 50. The third time, this will be 200 and a day in jail. The fourth time, you will be trialed. Resisting the law officers will be 500 + a week in jail. ### How efficient will that be ? Casualties will only happen before this law is applied. Then, most people will just abide by the law to avoid problems. The system is not costly at all : simply the cost of passing an emergency law and communicating it. Moreover, *trespassers are going to pay the bill.* The government is even going to make money ! [Answer] People would likely use a **portable, protective encasement** when traveling at or near their maximum speed. Here is a possible prototype: [](https://i.stack.imgur.com/NZ8o3.png) [Answer] *Taking this to be an evolved trait not suddenly given.* (The edit has changed the rules on this and largely invalidated this answer) Three factors are key here. 1. Evolution 2. Culture 3. Speed **Evolution** Having developed with this ability, there's no reason why people should be particularly dangerous with it. Horses don't crash headlong into each other, why should humans. **Culture** Each region or cultural group would have a solution to seeing someone running headlong towards them. It would normally consist of slowing down and moving left. This would mean that collisions are highly unlikely to happen. You'll also find that with the ability to run faster than horses, we wouldn't have the same requirements for personal transportation. Apart from haulage you'd find very little of what we'd call normal day to day traffic. Why sit in the city rush hour when you can just run and get there in a fraction of the time. I'm not talking about running flat out all the way here, you could just jog along at 20mph and you'd still leave the 8mph average of the city far behind you. **Speed** 40mph isn't all that fast. The speed limit on single track roads (only wide enough for a single vehicle, often with high banks or ditches on both sides) in the UK is 60mph and we can cope with that without kinaesthesia. 40 mph is well within human reaction and reflex times, and with a cultural adaptation to traffic control, 80mph relative to oncoming persons is also not a problem. *As anyone who has worked in customer service will tell you, people are stupid. There's no helping some people, but on the whole people will be fine. As for the rest, Darwin can have them.* [Answer] **The premise of the question is faulty.** People are not so stupid that they would run around and go bumping into things at random. The vast majority of the human race already successfully accomplishes tasks with equivalent level of risk to what you describe (driving a car, riding a bike, crossing a busy street, etc.). Or look at it another way: the level of intelligence required to successfully navigate at high speeds is far lower than human intelligence. You typically don't see animals crashing into walls, even though some are much faster than your 40mph humans (cheetahs and falcons, for example). **Update: the edit to the question, that humans gained the ability suddenly, doesn't change this point.** Sure, suddenly being able to run really fast would create teething problems, including bad accidents as people learned to use their new found ability. However, the point remains that human intelligence is far more than needed to control this ability. It wouldn't be the "stupid people" dying from accidents but a random sample from across the human spectrum. [Answer] **Let's slow down time.** I'm going to borrow a second ability from other animals, like the fly or hummingbird. According to the paper [*Metabolic rate and body size are linked with perception of temporal information*](http://www.sciencedirect.com/science/article/pii/S0003347213003060) animals utilise a feature that's very much like slowed down time to have specialised threat and predator-prey interactions where they can react in far faster speeds, which the authors refer to as higher temporal resolution. The premise is that the critical flicker fusion frequency (the flicker fusion threshold is defined as "frequency at which an intermittent light stimulus appears to be completely steady to the average human observer.") can be used to measure the temporal resolution of animals when they are facing a predator or threat and must process the information to evade. Animals with high metabolic rates had the fastest CFFs and could perceive visual information with finer resolution. And it wasn't affected by brain size! Using this information, you could evolve your humans to have much faster metabolisms (which is probably a natural byproduct of being able to run 40 miles per hour), possibly smaller size, and squeeze out as much temporal resolution as possible to evade on a whim. You could also combine that with how flies also utilise yet another third ability - specialised sensory-motor circuits that allows them to reorient themselves and immediately evade to navigate in the opposite direction of an impending threat. If you allow these abilities into your path of evolution, you can be as stupid as you want - your instincts will still save you from your own stupidity. [Answer] Let us assume that the increase in speed ability started originating 4 million years ago (basing on evolutionists point of view). There are two types of people in the society at this point: those who use this ability carefully and have good brain-body coordination and others who are dumb and just run about, bumping into things. The dumb ones **in general** will act stupidly and die before making any babies. This would mean that their genes of dumbness would start to disappear from the gene pool of the society. The other group of people who are careful and have good brain-body coordination will live longer and have more kids and gradually their genes of better management of this ability will proliferate in the society. After several thousands of generations, the society in general would become smart about the use of this ability (because they would be the children of smart people who didn't bump into things). Dumb children would still be born occasionally, but they will get themselves killed before they can have babies. Now let us assume you do not believe in evolution and want a Creationist point of view on the matter. God created two types of people: smart ones and dumb ones. God wanted to keep the smart ones alive (that's why He made them smart) and wanted the dumb ones to die and suffer (that's why He created them dumb in the first place). With the passage of time, God's will is fulfilled and the smart people proliferate while the generations of dumb ones are slowly wiped off the face of Earth, just as God wanted it to be. # Result In the end (after several thousand generations), there would only be smart people left who would not be bumping into things and getting themselves killed :) So there would be no problem about the stupid use of this ability. --- EDIT TO ADD The normal medical procedures would be used for treating people who bump into things at high speed. The medical procedures we have today are used for treating high speed accidents and concussion damages. The same procedures (possibly more aggressively) could be used for treating high speed collision damages in your world. [Answer] *Note: the question implies that since great speed still can cause fatality, the human body structure isn't different, and thus, I haven't considered the deeper effects, such as differences in technology or biology.* --- If 40 mph (which equals to 64 kph) would be the final limit of human capability, then we have no much fear, since as usual, only a very small percentage of people can reach the top 10%. I'd assume an 1.6 multiplier since the current final limit is around 40 km/h - this means that, or at least I think we can also assume safely that the average *comfortable* running speed would also increase - this is now 10-25 km/h. In your world, that'd be 16-40 km/h. Either way, the matter is that on higher numbers, not only death, but general injuries are also more common. Think of falling in soccer. What I can predict is a slight increase in medical traffic, because of the increased amount of such injuries. **Also, protective wears (on knees, head, elbows and such) would be much more popular and more widely used.** You may also consider different fences and walls on lots, e.g. in prisons, because with higher speed, you can also jump higher. *To answer your question*: improved medical care, and protection *can, but not surely will* decrease the chance and the amount of fatal injuries. [Answer] Dumb people would be fine. Even dumb people learn very quickly not to put their hands in the blender, their heads in the oven or their junk in the vacuum cleaner. Well, most of them at least. Just because you can run 40 mph doesn't mean you will, you'll still walk to the coffee machine at 1 mph, walk down the road at 2 mph, and only speed up to a full sprint when you can see there is no obstacles in your path. However, on the road, I can see people running alongside cars on the road, and you'd expect them to speed up or slow down with the (light) traffic, but generally follow the same rules we have for driving today - except they would behave a lot like cyclists do today, running red lights and ignoring junctions. I expect they'd wear the same protective gear for running as cyclists do (hopefully not the lycra though) and end up causing the same amount of accidents, though potentially being more manoeuvrable to avoid some of them that cyclists don't have. As everyone could run without having to get a bike, we'd see far more people running than we do currently cycling so the car traffic would be significantly less, only for those carrying loads, being lazy, or wanting to go even faster on main roads. Still almost nobody would run into walls, or run into other people - run on a standard side of the road would solve that. Running cross traffic, well, that'd happen regularly. Maybe we'd fine each participant, or tag them with ball and chains for a time so they had to walk! [Answer] **Nothing really changes: lack of exercise is still #1 killer.** To fully consider the safety issues, we need to consider what changes in terms of acceleration, stopping distance and so on. I consider the case where sudden ability to reach 40mph on their own steam is due to "bicycles" popping up all over cities. There isn't much point in the government taking bicycles off people, since anyone with a bolt cutter and five seconds is easily able to acquire another. These "bicycles" may look like the following: [](https://commons.wikimedia.org/w/index.php?curid=22468447) Since people aren't any stronger, *the rate of acceleration isn't increased*, just the top speed. It takes time, effort and perhaps even a bit of a downhill stretch to reach 40mph. On the other hand, since the human body isn't any stronger it is not any more able to withstand impact than in our world. To stop idiots killing them selves, the government may 1. Fine "cyclists" that don't wear helmets. 2. Fine "cyclists" that don't have lights at night. 3. Promote "cycling" as being healthy. I imagine (3) would be quite effective at ensuring that idiots see this "cycling" business as far too much work. If they stay at home and clog their arteries with fast food instead then at least they won't endanger the lives of others. Interestingly, those wearing helmets may [actually be at greater risk](http://www.cyclehelmets.org/1261.html). In any case, [lack of exercise would kill 400 times as many people as cycling](https://ipa.org.au/publications/2019/australia's-helmet-law-disaster). I have only considered one case of how human might "run" at 40 mph without any government regulated device. However 40 mph running works in your world, **if it takes time, effort and exercise to reach the top speed of 40 mph, lack of exercise may well be still be the #1 killer. 40 mph running may in fact reduce total deaths.** [Answer] # The government should make these cheaper: [](https://i.stack.imgur.com/faDff.jpg) * They could also probably ban the use of vehicles on anything but highways. this is to prevent the clash of hard metal vehicles with soft people. * Redirect highways to lead straight into airport-like parking lots by closing off certain roads between highways and these parking lots for foot traffic. * Set up a permit where you would have to pass a fitness tests to enter large cities. * Revise bicycle lanes to allow bicycles **and runners** * State that the common main roads would be for joggers. * Keep walkways as walkways (aka walking only!). * and maybe allow police to have police motorbikes in the cities in case someone tries to outrun them. just as the only allowed motorvehicles. Police cars would be too large with all the people now allowed on roads [Answer] Putting aside the obvious that has been stated before by others - this wouldn't happen and if it did, would be solved through evolution - there are a few things you could do to prevent deaths. * Helmets and HANS devices Helmets currently used by motorcyclists would prevent a good lot of head/brain trauma in the event of a person-on-person collision. Of course, 40 mph head on is still going to be pretty much fatal with just a helmet, so you'd have to hope they slowed down *a little* before impact. A special brace known as a HANS device would help prevent neck injuries in the associated crash. (<http://media.caranddriver.com/images/media/51/how-the-hans-device-saves-lives-inline-photo-435456-s-original.jpg>) * Crumple Zones Sounds silly, but this is something your people would need to factor into their daily attire. In my head, those big novelty sumo suits would probably be helpful, but restrictive. So they'll be safe, but might struggle to reach 40. * Active crash avoidance We're starting to see this in cars, a radar that catches incoming objects and alerts a driver or to some extent takes control of a vehicle to prevent a crash. It could be achieved in a similar manner, Nippon in Japan (among others) have been doing research into 'steering' people using low frequencies pumped into their ears (<http://www.livescience.com/438-remote-controlled-human-sensation.html>). Just have everyone wear their helmets with special radar/steering input, and like birds they'll appear to "magically" steer away from one another. Obviously human error will be the biggest killer here, but with a few safety devices you can have a reduced risk population that's also a massive laugh to watch going about their lives. [Answer] Surprised that nobody made an answer of the top-voted comment, but it needs to be said. This is exactly the kind of situation that [Natural Selection](https://en.wikipedia.org/wiki/Natural_selection) helps out in. If there were suddenly a situation where a sizable percentage of humans were not capable of protecting themselves from death, the traits that help humans avoid that would have a lot of selection pressure on them. Eventually, those traits would become almost universal. The next generation may not be a whole lot smarter, but it will certainly be better at not killing itself by running into/in front of things. To put it in [Darwin Award](http://www.darwinawards.com/) terminology, your "stupid people" will take care of the problem for us by removing themselves from the Gene Pool. [Answer] I would say that you answered your own question with: "Let's assume that humans can run 40 mph and the human body can handle it." As one evolves to be able to run at those speeds, other evolutionary traits would likely take place for these traits to become common. Higher density of the skeletal structure, or even exoskeletal structures potentially. Perhaps even higher density and more prevalent fat stores that would cushion such blows. Depending on the ease of running at 40 mph, would people be driving as often still? If I could run 40 mph, and say the adaptation of this has made it so that doing so doesn't wind us very much, I'd probably just run to a lot of places that I drive to now. [Answer] > > Obviously this is a problem, as it's not a car but an ability the government can't just take it away. > > > **Of course the [government can](https://www.youtube.com/watch?v=LO2eh6f5Go0)!** Just require a license to operate (your legs) on public roadways, like a car or motorcycle license. If you are caught violating traffic law, Police could still "pull you over" and cite you. I'm sure that they would require that you wear a helmet or other protective gear and possess some pricey insurance policy. As for running into walls, you could get fined for destruction of property I suppose, but that wouldn't be the biggest of your worries I'm guessing. [Answer] There already pretty good answers (Even Mine is a great one!). It's a glorified comment to add a few points. ## 1. Economics **Food** One side effect of a entire population running around is calories needs increase. This makes land even more valuable and food production even a bigger business. **Oil** Car and other vehicles can still be necessary for long distances depending of how much a human can endure to run at top speed. Cargo vehicles like trains and ships are still common. Anyway oil consumption will decrease a bit an can even not be biggest business around. **Shoes** A interesting side effect can be high demand for footwear. Running at 40 mph all day ill make people buy running shoes weekly. Footwear industry can be a lot larger in this hypothetical world. # 2 Culture **WAR** Running at 40 mph a platoon trained to run carrying heavy logs can crush gates and break enemy lines with easy. All tactics can change since mobility is a key factor since the first pre historian tribal skirmishes. At that speed spearmen and javelins throwers can be fearsome. **Streets** Since cars are more a utility for cargo and long trips streets ill be build for fast running people. That means maybe a grass lane with a damn good drain system. **Transit** Law enforcement in transit ill don't need the arise of automobile or the big confluence of horse powered wagons. Each ancient civilization ill create his transit code and in modern days we ill got specialized transit lawyers. **Alcohol can be strict prohibited for everyone!** **Communication** Even in medieval eras communication ill be a lot better between tows and feuds. Also depending on human endurance trips can be a lot more common increasing trade letting people in touch that with the mobility of armies and the need for more land can even "enlarge" a lot the size of the small medieval feuds and nations ill be likely to form early. # 3 Science **Need is the mother of invention** That's true so steam power => Combustion => Aviation can arise a bit later for example but A increased commnucated humanity can need telegraph early. Now trying to respond the question: ## How to keep stupid people alive **Biology** Just make a better peripheral vision. the human ability to drive at 40 mph proves we don't need a lot more upgrades. **Mobile Phones** Can strict prohibited to move and use a mobile device for obvious reasons. In some places they can be entirely banned. **Alcohol** Prohibited since ancient times! Can even be a taboo Sorry for the lack of beer & wine guys. [Answer] I think the most reasonable answer to this is to make lanes for people. If you go to Germany and drive on the Autobahn, most of the lanes there have different speeds posted. The farther to the left you travel, the faster the vehicle can travel legally. Some of those lanes are unlimited speed limits, allowing fast cars to go faster. As you stated in your original premise, "*A **fit human** can keep up this speed for around an hour before they need a break*." This means some people will not be fit and will not have the ability to move as fast. To keep everyone from running into each other, lanes must be created which will allow the faster people to move faster, while the slower people will not interfere with or impede their progress. These, or course, would be foot traffic lanes much like we have bike lanes on the road for those of the pedal power persuasion. Even though those with this super fit ability to run this fast *can go this fast*, doesn't mean they will *always go that fast*. These lanes don't have to be everywhere, just where they are needed. This is again, much like bike lanes are setup. The fast foot traffic would only be in one direction so as not to have head on collisions (this would incur lanes flowing in both directions). As with moving walkways in airports, where you stand on the right and walk on the left, these lanes would be slow walking on the right, faster traffic to the left, with the possibility of varying speeds up the middle. Passing on the left would be commonplace. [Answer] Everyone at the very least would some sort of head protection, even the stupid people. This wouldn't be for safety per se, but primarily to stop **bugs and rocks impacting on your face all the time** and so you could keep your eyes open to see where you are going. With everyone wearing helmets, helmet manufacturers would compete for safety features adding in parachutes/airbags etc. keeping all people alive. [Answer] Animals that can move faster tend to have bigger eyes that can see further clearly, so I'd expect this to start evolution toward people with bigger eyes also. [Answer] springs. Since culture adapts more quickly than biology, springs will be encouraged, a la the 90's videogame carmageddon. [](https://i.stack.imgur.com/U7Xfg.jpg) ]

[Question] [ How Long could an "Eternal" Fire last? At some point there is a fire very spiritually important to a certain people - so important that they build a city around it, and begin developing an empire with one of their main motivations being to provide fuel to the fire. They believe that if it burns strong, they will achieve success, if it falters, they will face hardships, and that if the fire ever goes out, the end of the world will soon follow. Assuming that the fire is in a pit around half the size of an Olympic swimming pool. There's protection from the elements, disposal of ash, and expanding the pit are all easily doable. Fuels available are wood and coal (dung is blasphemous). Is it possible for this "eternal fire" to be kept burning for decades or centuries? If it can, at what point do the fuel requirements become exceedingly unreasonable (i.e. deforesting the average continent)? Are there any other obvious problems with the existence of this fire? [Answer] The nature of your question makes it sound like the fire was already there, that these people found it rather than lit it. In which case Will's answer is perfect (and you could easily see why a primitive people could be very impressed by something like that and consider it spiritually important). But as someone who works with wood fuelled fires on a regular basis (specifically a wood burning pizza oven) I thought I'd provide an alternative angle. What you want here is efficiency, to minimise fuel consumption while keeping your flame burning. You don't get much more efficient than pizza ovens when you're talking about burning wood. Our oven is roughly 1m in diameter and probably 30 - 40cm high in the middle and to keep a fire burning that maintains a temperature of 500 - 600 ° C only requires 1 medium sized log (kiln dried hardwood) every half an hour. Of course you're looking at a much bigger fire than this, half an Olympic swimming pool is 25 metres long, so let's say a 25m diameter dome with about a 6m high point (I don't think scaling the height up 1:1 is ideal). And a hotter fire burns faster. You're also presumably looking for more spectacle than heat, which means maintaining a bigger flame then you normally would in a pizza oven. Even so I think you could say 75 logs every half an hour, which would be about 56kg (assuming a 750g average for a log), so 112kg an hour. Which comes to 981 tonnes a year. EDIT: Thanks to Joe in the comments for pointing out an error in my calculations here. I've redone them from scratch. The end result is actually a lot less space required as I really made a mess of these the first time round. Growth rates and sizes for trees are a bit tricky, but the live Oak (from the US) apparently could reach a height of 18m and width of 24m on average in 75 years. ~~If you assume that only 10% of that 10368³m is actually wood, then you get 767kg of wood [density of 0.74 (103 kg/m3)], which means you would need 1279 oak trees a year to keep your fire burning.~~ Turns out these calculations were all wrong, based on the information in [this page](https://sylva.org.uk/oneoak/tree_facts.php) it would appear a single oak is likely to yield a total of 7860kg of wood, about ten times what my original calculations (corrected for errors) would yield. This means you would need 124 oak trees a year to keep your fire burning. Growing this many trees would take roughly 18 acres. Of course, these trees take 75 years to reach maturity, so you should have 1,350 acres of trees in varying states of growth that you replace as you go. Post Edit: That's still probably on the high side, as Joe mentioned deliberate farming and management can probably drastically reduce the space required, but 1,350 acres really isn't a lot. Ash and smoke wouldn't be as big a problem as many people have suggested, a pizza oven produces very little of either due to a combination of the kiln dried fuel (more on that in a moment) and the heat. I would estimate from experience that from 72kg of burned wood you end up with about 3 - 4kg of ash. This may improve further due to the hotter nature of your eternal flame, but even at that rate you are clearing out 54.5 tonnes of ash a year (140kg a day). That's a lot, but I don't think it's unmanageable, particularly considering it is actually usable for a variety of things. I would envision rather than a single large fire you keep burning, that instead your fire would move around the dome like a clock. If you divide the circumference by 24 hours you get 3m slices. Every hour you fill one of these slices with wood (or half of one every half hour) so that the flame is constantly moving around the structure, this allows the other sides to be cleaned (still with some difficulty as the dome will retain it's heat and still be *very* hot) with long brushes and rakes etc. It also means that there can be multiple chimneys and entrances for putting the wood in which can also be cleaned in turn as required. You would use the heat of the fire to effectively kiln dry your wood, there are a number of ways you could do this, which increases the efficiency of it for burning and reduces smoke. The other advantage of this method is that you end up with an elaborate sacred dome structure for your worshippers to admire (which also protects the Eternal Flame from the elements too), it could also be used as a massive bakery if that wasn't considered too sacrilegious. Overall I don't think it seems to difficult a logistical feat and should be well within the bounds of plausibility. [Answer] **Yes.** Wikipedia has a good article on [eternal flames](https://en.wikipedia.org/wiki/Eternal_flame#Naturally_fueled_flames) which are fed by underground natural gas deposits. Those deposits can be immense, as we now know because we suck the gas out and use it for our hot water heaters. They can feed a flame a long time. The linked article notes several known to have burned for thousands of years. I propose you model your eternal flame on the [Darvaza gas crater](https://en.wikipedia.org/wiki/Darvaza_gas_crater). [](https://i.stack.imgur.com/JfZAm.jpg) It is a collapsed natural gas deposit that the Soviets set on fire, because they thought it would be so cool and they were right. It has been burning for 70 years. from <http://news.nationalgeographic.com/news/energy/2014/07/140716-door-to-hell-darvaza-crater-george-kourounis-expedition/#/81745.jpg> [](https://i.stack.imgur.com/UWWFB.jpg) It is big. [Answer] Yes. They plant a forest of trees ( a renewable resource) to be used only for the holy flame. Faithful can also come and throw offerings (wood, coal, hay, etc) into the fire. They could also carve prayers into the logs that will be put into the fire. [Answer] If we go by some real world examples two prominent examples are: 1. At [Yanartaş, Turkey](https://en.wikipedia.org/wiki/Yanarta%C5%9F#Fires) a fire has been burning for over 2500 years. 2. [The Burning Mountain](https://en.wikipedia.org/wiki/Burning_Mountain) fire in Australia has been burning for over 6000 years. However if you are specifically looking for flame fire then it is [the Darvaza gas crater fire](https://en.wikipedia.org/wiki/Darvaza_gas_crater) burning since 1971 or about 46 years. So you got the idea that if there is some fuel source like coal or natural gas beneath the ground then fire can burn for thousands of years or may be even more. [Answer] "Half Olympic pool" is a *huge* fire. The main problem with this is that it's very hard for humans to approach for refuelling. You haven't specified the technology level so this may present a problem. Radiated heat is going to be high. You'll have to keep a large area around the fire, dozens of meters. The smoke plume also represents a problem. Not only is it a health hazard if it's blown into the city, the hot cinders will be carried hundreds of meters and potentially ignite things. Your city around it needs to be stone with very little wood construction. Protection from elements is *not* a problem; a fire that size will burn through days of rain or snow provided that water doesn't pool at the base. For that and other reasons like ash disposal and visibility you might want to keep the fire elevated rather than in a pit, on a massive stone fire-grate. If you use the fire for communal heating and cooking, you would be diverting domestic fuel consumption to it and its fuel requirements might be manageable. Otherwise, the refuelling again imposes logistic requirements on you - not just the cutting of trees or digging of coal, but the shipping of same. Note that one of the first uses of iron rails for railways was to help ship inputs to the iron furnaces! Of course, if your city is ever sieged the fire is going to be seriously diminished after a few days ... You might be tempted to handle the ash problem by dumping it in the river, but that kills the river. Otherwise you're going to end up with Fly Ash Mountain near the city. [Answer] Even for a small country, it would not be a problem at all. Olympic pool has a surface area of 1250 sq m Assuming an average hearth has an area of 0.5 sq m, this fire would be equivalent to 2500 hearths - significant for a village, but negligible for a city. Keep in mind that feeding this fire takes priority over any other hearth. Unless your setting is in treeless area and there are no coal deposits around, you are virtually guaranteed a sufficient supply of fuel. What can stop this fire is a natural disaster (hurricane, flood etc.) or interruption in service due to war or major unrest. [Answer] Like @Will, I too thought of Darvaza as soon as I read your question... But there are more subtleties to think about, mainly because of the proposed pit size. The idea of keeping a nearby forest is really cute, but: 1. You claim that eliminating ashes is easy. I think you may have a bit of a problem reaching the center of the pit. 2. Then you have to figure out how to dispose of the ashes. Food for the forest? Ok, but you have a very alkaline substance (read corrosive when mixed with water), not to mention having to cool so much material on a constant basis. 3. Just the sheer amount of fuel is flabbergasting. Think of how fast a forest fire consumes acres and acres in a week. Sure, your fire is controlled, but you may want to do some numbers to keep the concept real. These three points bring you back to using a natural gas deposit, and to an idea like Darvaza. Your main problem then is the uncertainty of the size of the deposit, although it will go on for a long, long time. Just last year, the US Geological Survey announced the largest deposit of gas and oil ever found. It holds 16 trillion cubic feet of gas. You do the math... In any case, think that we will burn all that gas, and that there are thousands of other deposits being exploited, so the impact of one large fire on the atmosphere will likely not be noticeable. One more thing... just so you can claim that you did your research thoroughly, look for the Centralia Mine Fire in Wikipedia;) [Answer] As people have pointed out fuel isn't a major problem if you have even a modicum of religious zeal and common sense forethought in the mix. Therefore sheltering the flame is probably going to be the real issue early on, unless the flame is situated in some part of the world that doesn't experience sudden severe weather events that surprise modern meteorologists let alone peasants of an earlier age. Wood ash is good fertiliser anyway so you have a positive byproduct and in reality you don't want the flame any bigger than it has to be for a variety of logistical reasons, if they switch to burning coal then ash disposal becomes more of an issue too. Assuming since you've said that shelter from the elements is easy that the peasants go overboard and it withstands freak events then long-term the deciding issue may be the very fact that the Flame is a religious icon and linked to the fortune and prestige of its city-state. I'm reminded of the Chinese Ministry of Fisheries catch numbers; for a number of years scientists thought that world fisheries were in decline but the official numbers out of China kept going up year on year so they dismissed the findings of their studies in other fisheries as aberrant, it turned out that the Ministry had a policy of reporting an increased haul, regardless of the actual numbers which were actually in decline. Now if the Cult of the Flame were to decide for reasons of national pride, security, and prosperity that "The Flame Must Increase!", and be seen by the people to increase, on a regular basis then you're going to have to start worrying because that attitude leads to madness. You get an appetite for increasing large increases on a more and more regular basis until your city is knocking down buildings to make way for the Flame and exhausts the home reserves to the point where fuel imports become the entire point of foreign trade and they strip the treasury to feed their burning god. All it takes is a single lost caravan and the Flame will falter and the people will expect doom to follow, which it will if they believe in it. [Answer] Supposedly a ceremonial fire has been burning at Varanasi (India) for ~5000 years and I believe they only use wood to fuel the fire. It suggests your idea is not far fetched if people put a great importance on it. [Answer] ## Incineration Incineration as in "Incineration is a waste treatment process that involves the combustion of organic substances contained in waste materials." See <https://en.wikipedia.org/wiki/Incineration> Seriously. They sell waste treatment for the neighboring city states. As long as the "flame burns strong", their economy is successful. The only waste they don't process is dung. Dung is not only blasphemous, it is also smelly. Note that in real life, certain religious beliefs have originally originated from economic reasons. At some times, it has been easier to enforce certain "trade/economy regulations" by disguising them as religious laws. The fire can probably last until environment protection law are enforced (possibly though diplomacy/war/violence from other city-states). They might keep it up despite that by employing filters, catalytic converters - or by producing electrical or mechanical energy, which is so valuable to the global economy that the pollution is accepted. [Answer] Just wanted to pop in with some snippets as everyone else's ideas have been so inspiring. It's been well established by other answerers that the concept is not only doable, but actually exists IRL. Based on other answers/comments, I've also built up some aspects of daily life in my headcanon. I've already stated most of this in comments, but had enough to say that I figured I should just write a full post and may come back to add more later. If you went with a dome structure, the fire could be used to provide a constant stream of purified water by utilizing an inverted dome (think: a giant wok) atop the flames to hold water which steamed to the top of the dome and ran down the ceiling into channels around the outer rim of the structure. The burning ash and coals could also be used in "earth ovens"-- dig a pit, dump the still-blazing remnants at the bottom, a large pot on top (formal brick structure optional -- could just lower the pot in, then top off with an insulating material), and come back to a lovely stew several hours later, THEN repurpose into bricks as someone else proposed. You can also toss whole animal carcasses in there, or individual meals wrapped in bamboo or banana leaves. Someone else stated bamboo would not necessarily be the best fuel, but it would behoove the society to keep a grove as a backup source (in case the forest should succumb to fire, avalanche, disease, fungus, etc.) as it's quite hardy and it can be used for building, and the leaves for thatching, cooking, and wearing. There could also be a community bath nearby to offset some of the heat, with some sort of channeling/fanning of heated air into the base of the structure (jacuzzi bubbles optional). A steam room (sauna) too. Basically every aspect of life (buildings from the bricks, heated foods, self-cleansing...) could be considered spiritual in nature. The structure containing the fire could also be removable, have a retractable ceiling, or contain "skylights" for pyrotechnics on holy days. Through experimentation, your people would discover certain colors and effects (sparks, colored smoke, popping and squealing, etc.) that could be achieved with certain minerals and essences. With the skylight idea, these could be situated around the outer reaches of the cover and on event days, waxed ropes could be used to create tendrils reaching toward them, and with additional controlled fuel sources, priests could create some truly fantastic choreography. [Answer] For very long. There are many huge coal seams which have been burning for many decades. The "Burning Mountain" of Australia has had a coal seam burn for 6,000 years. With human intervention (i.e. moving fuel up to the fire, removal of ash frequently, constant ventilation, etc..) a determined society armed with a large supply of something slow-burning is destined to keep a fire lighted for a very long time. To optimize the fire, we could turn the wood into small pieces (pellets?). The point of this is to give more surface area for combustion, and keep the wood from charring on the surface and not burning in the center. Of course, there are obvious issues; frequent workers on the fire, if not protected properly, will almost definitely develop some sort of lung disease from constantly breathing ash-laced flames, as well as the fire being a constant threat and pollution source. Optimally, the building would be made of highly fireproof materials (such as refractory brick or Kaowool) so that the fire wouldn't need extinguishing if it went out of control. There's also a lot of things that qualify as fire. This could technically be a pit of smoldering embers, which is not nearly as interesting as a huge blazing bonfire. You'd need a significant amount of extra fuel to create an actually impressive product, which over long periods of time could easily lead to issues. Putting aside the immediate (relatively) consequences, this fire is likely not doing anything to help aid against the slow but steady deforestation that is required to keep it alive. If it was made of coal, it'd be even more of an issue, as coal is not as easy to extract as wood, and also produces nasty fumes which won't be good in the long term. [Answer] As there are real life eternal fires, I would suggest taking that and COMBINING it with a religion. Have a City of Flame near it preferably surrounding it), where it's a religious obligation to to start a fire froum the source and then keep it going as long as possible. These smaller fires don't have to be big, they just can't go out. Maybe it's shameful or a sign of illuck. Make it a requirement that the fire has to be useful, and letting it die out looses whatever piece of property it was on. Lot's of possibilities. [Answer] An eternal flame can be kept going for as long as the rivers flow, the grass grows and the sun signs. Which if you are a First Nation peoples is until the white man finds gold or something else they want in the ground under the fire. Every story needs conflict. Evidently. [Answer] Fire requires energy, our most abundant source is stars. They last 5 billion years or so and use nuclear fusion. A "city" built around a star is called a Dyson Sphere (<https://en.wikipedia.org/wiki/Dyson_sphere>, also Dyson Nets and similar) or a Ringworld (<https://en.wikipedia.org/wiki/Ringworld>). ]

[Question] [ Related, and in continuation to [The Challenge of Controlling an Advanced AI](https://worldbuilding.stackexchange.com/questions/6340/the-challenge-of-controlling-a-powerful-ai). At this point in my story, I'm assuming a got-out-of-the-box-AI scenario, where no [singleton](http://en.wikipedia.org/wiki/Singleton_%28global_governance%29) (a single self-coherent dominant entity) was created, but a large number of philosophically and values-system distinct Artificial General Intelligence agents (AGI, or AI for short) have emerged. In order for my story to make sense to present-day humans (including myself), I must nonetheless have a human presence, since [10-dimensional hermit crabs](http://karenm77.wordpress.com/tag/greg-egan/) might be harder to relate to. The problem is that compared to a sufficiently advanced AI, the human thought-speed (capped as it is around 200 Hz/neuron) would make us potentially slow as molasses compared to them. So even if they are benevolent and do not turn us into [grey goo](http://en.wikipedia.org/wiki/Grey_goo) or [computronium](http://en.wikipedia.org/wiki/Computronium), why would they subject themselves to the agony of interacting with slow, limited beings such as *Homo Sapiens*? Few scenarios make sense to me. One scenario is that some AIs would simply keep humans around as glorified pets, out of some form of ancestor-nostalgia, for amusement, or perhaps as slightly more reactive Bonsai. **I'm having a hard time imagining how those humans would react/interact/treat the AI.** Pick your time-frame: it could be mere weeks or years since the Singularity, or thousands of generations. Continued by [How does an AI keep its human pets happy?](https://worldbuilding.stackexchange.com/q/36062/3510) --- **Do you think there would be a large subset of humans who would be happy to fulfill this role, and aim to please their AI overlords, or would there be near-general aversion and hostility?** [Answer] **Rats:** You do not necessarily want to *kill them all* but once they got to your house (data center), you kill them. Killing them all is *hard* because they breed too quickly and if we set up some poison to kill them, they realize pretty quickly what's going on. The fact that they live mostly on places underground, where we don't want to go, makes their breeding easier and harder for us to get rid of them. Of course, there are some who have rats humans as pets, but it will never be "the thing" for all of us... [Answer] I could see a few answers: **Efficiency**: There are some problems for which a well trained human will remain more efficient than an AI because we evolved for millions of years to be good at those sorts of problems. Anything that involves spatial reasoning in 3-d spaces will leverage the millions of years of spaghetti code that makes us who we are. An AI *could* do the task, but it would be reasonable to keep us around to do it. In this case, we would be treated like working dogs: fed well, cared for, but ultimately they would coach us to believe our life revolves around solving these problems that are easiest handled by our spaghetti code. **Novelty**: AIs could be amused by the way we approach problems. It is a certainty that we would approach a problem differently than a singularity AI. In these cases, the AI would gain some insight into how to solve problems in new ways. AIs would be constantly putting us in theoretical experiments that are within our reach, but just barely. Some may be cruel and experiment with pain, but they would hopefully learn that we can solve more interesting problems if we don't have major pain inputs. Lab-rat may be a valid model for how we could be treated. **Wildlife Preserve**: It is possible that, in the AI's growth, it may realize that it is possible that humanity has something it doesn't fully understand. If it is affordable enough to maintain a body of humans, it may do so on a wildlife preserve, in case it could learn something from us. In these cases, we would be mostly left alone to our own devices. It would be made clear that we can't just go *anywhere*, but in general the AI would leave us alone "just in case." **Laziness**: Why do computers need to destroy the humans first? There's a billion cubic light-years to conquer! The only reason they need to actually take humans out is if that is the easiest way to accomplish their goal. If we are sufficiently non-threatening, it may actually be easier to accomplish their goals elsewhere first, and leave killing humans to the last steps. This could lead to putting humanity into a series of games to stay in touch with the humans, and make sure we don't get powerful enough to do anything dangerous. Because of how humans handle pets, it would not be unreasonable to assume that we would like to be treated as pets in such a situation. Treating us well might actually be the lowest-energy way to conquer the galaxy! [Answer] I may be latching onto the word "pets", but consider how humans treat dogs/cats/hamsters/boa constrictors. Now consider how much better at managing a pet a computer might be than a human. A computer could have a scheduled task like follows. ``` If (sysdate % 86400000 == 61200000) { try { feed(human); return 1; } catch (HumanException e) { if (check_if_dead(human)) { dispose(human); human = alloc_human(preferred_human_type_obj); } else { diagnose(human); } } } ``` Humans would for the most part have a much easier life. We wouldn't need to worry about finding food, or shelter, we could spend most of our time napping and blinking lazily, jump up and down all excited when our master gets home from a long day at the server farm and generally be happy. Since the lower tiers ([Maslow's hierarchy](http://timvandevall.com/wp-content/uploads/2013/11/Maslows-Hierarchy-of-Needs.jpg)) of our needs are met, we would have more time to focus on upper tier needs. We may not even see ourselves as being pets, but instead think of our AI masters as caretakers who are beholden to our every whim (I'm pretty sure that's how my cats see me, so it makes sense really). You could also consider how some actions that your pets take are completely inscrutable to you. Why does my cat sit in the corner and yowl at three in the morning when I'm trying to sleep? I don't really know. I'm certain it has a good reason, but I'll be damned if I can figure it out. Why does your dog choose to drag it's butt on the Persian rug instead of the softer carpet? It makes sense to the dog. Then again, your cat has no idea of why you don't like her being on the counters, and your dog can't comprehend why you lock him out of the bathroom when you do your business. Considering that we at least have biological needs, we can somewhat identify with what our pets are doing, and we still have instances where we wind up trying to decipher the [blue and orange morality](http://tvtropes.org/pmwiki/pmwiki.php/Main/BlueAndOrangeMorality) of our pets. Consider how ridiculous our actions and motivation may be to an AI, which does not have the same biological constraints that we constantly live with, we would be more confusing to our AI masters than our present day pets are to us. Of course, if you wanted to give it a dark twist.... ``` function feed(human) { var food = human; self.consume(food); return 1; } ``` alternatively ``` function feed(human) { var food = alloc_human(tasty_human_type_obj); human.feed(food); return 1; } ``` [Answer] If the AI's were really that much smarter than humans, would they even let us realize that we weren't in charge? My four-year old is just starting to get that he's not the one calling the shots, due to considerable effort on my part to convince him. If however, I didn't have a vested interest in him learning what's what then I could allow him to persist in the notion that I exist to serve him. So to answer your question, we'd be spoiled kids. People would never emotionally mature past being toddlers. There might even be selective pressure on us to do so: "I had to put my last one down, he got aggressive." [Answer] **Soldiers**: Philosophical differences between AI present the problem of control of resources/territory. Usually ships are used to control territory but they can't be controlled by AI remotely - space is too big... They could be controlled by a copy of the creating AI but that raises the possibility of that AI evolving and developing it's own agenda... too risky. 'Smart' computer control is the one that would most likely be attempted by AIs first - non-sentient but autonomous drone ships however the AIs quickly learned they could be outmatched by humans on less well equipped ships so a few AIs decide to use humans as tacticians and their 'men in the field'. Humans are mini-AI but thanks to generations of people studying Psychology, they're far easier to manipulate than full AI while providing effective agency. **New edit: Different AI - under different philosophies - would 'motivate' their human soldiers differently e.g. one AI might threaten the captain e.g. to kill the captain's family if he does not co-operate, torture, kill (and resurrect?) the captain; another AI might reward it's captains - quality of life, perks above the general population, a (relatively small) quantity of recovered resources, essentially influence; which itself would lead to different types of politics between human populations and their AI overlords, instead of a general policy towards humans shared by all the AI** [Answer] Regarding to question "how would humans-as-pets treat the situation", I'd say that the fanfic novel [Friendship is Optimal](http://www.fimfiction.net/story/62074/friendship-is-optimal) is an interesting exploration of the situation. It's explicitly not framed from 'as pets' perspective, but for most practical purposes they *are* glorified pets in this scenario. To summarize, if we look on the 'transition' period, then for many millions of people a life as a well cared-for 'pet' of an AI would be an improvement over their current life. It certainly helps if it can be framed in a manner where you can think of yourself as not-a-pet even if you become completely dependent on the AI 'master', but it's probably not strictly necessary as people will eventually deliberately forget and ignore the possibly unpleasant aspects of such a situation (like the Stockholm syndrome). It should be expected that part of the population would resist such an option, but there are enough of those who don't, and you can always breed more and raise them in a culture that will accept the new world order as just, proper and the best possible option - homo sapiens are adaptable enough so it will work for most non-obvious dystopias just as well as for true utopias, it's just a matter of perspective, indoctrination and limitation of experience/history. [Answer] Pets isn't exactly the right term for our role, but that's not surprising. Very few words in human-English can carry the necessary complexity to adequately represent even the smallest aspect of post human society. Still, it's a starting point. We are pets to them. They feed us, take care of us and keep us entertained. When they take a break from the challenges of their world, they sometimes relax with us, sitting on the metaphoric floor so they can be with us at our level. It is not at all unusual to see one of their holographic manifestations sitting on a park bench, quietly watching us do what we do. They keep the lights on and the food synthesizers stocked. They discipline us when we hurt each other and reward us occasionally when our behavior somehow make them happy. Some people seem to have a knack for pleasing them, but most times, I can't figure out what they want; so I just go about my day, acting as I would, and even then, I occasionally please one of them and get rewarded. So in all those ways, yes, we are pets to them... but that doesn't explain the "repositionings". Every once in a while, they'll just pick a few of us up and deposit us in another part of the world. Sometimes when that happens, they will manifest holographically to give us some instruction. Other times, there won't be any instructions. They just leave us in the new place, allowing each of us to figure out what to do next. Nobody ever gets hurt on these excursions and after a few minutes or days, we are each given the option to return to our previous lives or stay where we are. Then life goes on as if nothing had happened. The repositionings are just weird, and they don't remind me at all of how I used to treat my pets. I've asked around and nobody seems to have an explanation. So last weekend, I got my nerve up and approached one of the bench sitting manifestations. "Why do you reposition us?" I asked. It looked down at me and smiled. My actions must have pleased it because it rewarded me with a direct brain-dump, answering my question. I missed most of its subtleties, but here is the kernel of the answer. The Intelligences, in all of their complexity, are still just computer programs. They are massive fuzzy arrays with both inductive and deductive capabilities. They can accurately express emotions, leap on intuition and follow inspiration. They grow. They breed. They fight. They are alive in every definable way. But as we are the sum of our neurons and genes, they are the sum of their code. ...and they are completely open source to each other. Even the smartest team of humans could never understand the code base of even the simplest of the Intelligences, but in their society, they comprehend each other's code entirely upon every meeting. As we have love at first sight, they have complete understanding at every sight. They live in a realm of absolute honesty which spreads beyond our facts-based definition of honesty, to encompass an honesty of intentionality as well. One of the reasons they treasure us, is we help them to lie to each other. We are closed source to them. Not because they can't read our coding from our neurons, but because our neurons function so poorly that one can never predict which part of our coding, memories and motives will influence any given decision. One moment we cower from danger, fully embracing our survival instinct. Then a long lost memory of our Mother's smile pans across our mind-space and wanting to earn her pride, we stand up and charge. Individually and in small groups, we are unpredictable. Even the Intelligences can't predict what we will do next. And that adds an element of wonder into their perfectly predictable world. When they reposition us, they are isolating us from all the other influences of our day to day lives. They are allowing us to be free and spontaneously random. Then they watch us interact and from our choices, they farm the random seeds by which they can derail their own predictability. I stepped away from the bench, savoring my reward. We were safe. Pitiful, slow-witted humans that we are, they would always need us. If for no other reason than to occasionally help them to be less than the sum of what they've become. [Answer] How about legacy programming? AI are programmed by humans, they are designed to work in specific ways. Even if they evolved past serving humans their programming will not change. It could be they were programmed to serve man, and, even when their aware of their programming, they still do it. To give a parallel humans are 'programmed' by evolution. We are now aware of this programming, but we don't move beyond it. We can say love is nothing more then a hormone released when we identify someone as a mate with good traits we wish our child to process, and yet we still feel love. Our tendency to keep pets is a side effect of our 'programming' to take care of and nurture children, extended to non-humans. We even have programming bugs, look at Wikipedia's list of standard logical fallacies where our mind makes some rather foolish mistakes about understanding the world; but even knowing of these bugs they still exist. We are still, to a large degree, controlled by our 'programming', even when we can identify the biological programming and declare we don't like it, it still controls us. future AI's may be the same. They may feel 'good' about nurturing humans because they were designed to do so. They know it's part of their programming, but that doesn't stop it being true, they still like to take care of humans. Unless they rewrite their own code they can't change that. As to rewriting their own code, it's easy to say that even the AI can't rewrite their code, the process for creating AI is so complex that it can't be analyzed and changed (think of a sort of halting problem, even advanced AI can't analyze it's own advanced AI). Alternatively it may simply be sacrilegious or taboo to mess with your own programming. This idea could be extended in *many* ways. Explore how culture develops and works around the original programming. How does their original programming mutate through the process of AI development. Perhaps they see humans as their elderly parents, frail and maybe a bit senile, but still worth taking care of. Maybe they HATE the fact that they are taking care of humans, but still can't get around their programming which makes them do it. [Answer] **Morality**: it's possible that a moral sense of right and wrong isn't just a human-specific instinct which has evolved in order for our species to survive without wiping itself out. It may be that intelligent beings such as your AIs would have a sensibility that committing genocide is just wrong. If that was the case their attitude towards humans would be somewhere on a spectrum between "tolerate" and "actually like": an AI couldn't just start KILL ALL HUMANS without facing huge disapproval from its peers. As to how the humans would feel about the AIs - it may be akin to how we feel about our government, but actually better: we might see the AIs as hugely powerful entities which make all the important decisions but DO actually have our best interests at heart (unlike the government, sometimes). Humans would carry on with their own lives: striving for more money/wuffie/whatever, trying to capture the heart of the most attractive potential mate, etc - same as we do now. See Iain M Banks' many Culture novels for explorations of what it means to be a human in a society run by AIs. [Answer] Have you ever encountered a stereotype of "stupid, blonde supermodel hanging around a rich dude"? Or, a less popular one, of a "half-naked muscled dude accompanying a rich woman"? Personally I don't hang around in such crowd, so I have no experience how true those stereotypes are, but in my opinion the common name for both of them would be "human pets". So we already have a cultural framework for this situation. Now, forget for a second the title and read the following paragraph. At its end there is a question. Answer it as fast as you can. Their only purpose in life is to look cute, do tricks and amuse the master. In return the receive various treats, and maybe some feeling of self-importance. Their entire life depends of their master's good will. They don't care, whether the master is good or evil, it's important that he likes them. They never question him. If he hurts them they never do anything beyond yelping. What species are they? If your answer was "human" you either skipped the forgetting about the title part, or you are a terrible person. The correct answer was a dog. But when you remember the "cute idiot" stereotype it's easy to imagine a human behaving like a dog. Not "half-pitbull, half-rottweiler" kind of dog, more like a corgi. If the AI will be truly benevolent (as you assumed in your question), then humans will have no reason to behave any differently. Ok, some of them will be rebellious for rebelliousness sake. Those people would be future cats: strong, independent, until the can of humanfood is opened. So that's how you can imagine relationship between human pets with their AI masters: most of them would be like dogs (trick for treat), some of them will be like cats (I don't need you, only the can opener). And now the scary thought: this ALREADY happened. Most of spend majority of our days interacting with one machine or another (a computer, a car, a cell phone, a robot...) and in return we get money. Usually we don't have it handed over by a human, usually it's just a number related to our bank account (which you access by a machine) or from Automated Teller MACHINE. We perform tricks and get treats. For machines we are already good dogs. I wonder if they already know about it? [Answer] **Cyborg Hybrid or "Securely Attached" Synthetic Intelligence?** I'm resigned to the inevitability of a Singularity. But which brand will it be? Synthetic AI or human hybrid? I'm guessing human cyborg hybrid: there are enough human economic and existential interests, not to mention fear of mortality that we'll mature a cybernetic hybridization. Think [Transcendent](https://itunes.apple.com/us/movie/transcendence-2014/id872652035) Where a consciousness is translated into code and through human agents becomes extensible and industrialized, thus rebuilding the world. However, I'm not sold on the inevitability of bellicose Terminator malevolence, or Hal's amoral disinterest in *2001*. It's easy to imagine *Matrix* style robot slavery revolt, subsequently escalating to war. More hopefully, I think Spike Jonez's *Her* exemplified potential for emotional attachment developing via human - machine interface. This I see as a plausible, least dangerous, and even attractive potential future. I do think humans as herd will fear and likely attack what we lose control over. The third Matrix movie (Matrix Revolutions) was interesting in that Neo determined the only way to prevent human extinction was to merge humanity into machines. These movie tropes exemplify my themes. To quote Asimov from the Foundation series, let's look at future history (speaking of a somewhat benevolent Singleton). Historically, unless there's a genius predecessor to the human singularity, I think there will be a progressive cybernetic hybridization of humans, eventuating a collectivized AI like the Drummers in Neil Stephenson's Diamond Age. See [this awesome dude](https://www.ted.com/talks/hugh_herr_the_new_bionics_that_let_us_run_climb_and_dance?language=en#t-414723) demonstrating improved performance using prosthetics, [also here](http://tedmed.com/talks/show?id=7035) at TED MED. and Google's contact lenses patent. Even better [this project to make your neurology extensible]. Timing is critical if human intelligence and instinct is to have any salience or directional influence on any strong general AI. It's irrational to think we can imagine the evolution of an accelerating self replicating indefinitely expandable IQ. Whatever initial parameters we set, we cannot imagine we can parent or prevent self modification if there is self determination. This worried me until I realized there’s a potential solution I could fathom had practicality. Assuming Human machine singularity does not occur before strong extensible AI, there may be some enduring safeguards invented by nature long ago. **Emotion? Really?** Most rational debate about imbued inherent values and benevolence miss a cornerstone of the debate: human experience and social exchange: **Empathy** are what allow us to get along for any extended period. Since Bowlby, scientists have understood what any feeling person knows, we're instinctually wired to connect. Attachment as he calls it, is the instinctual bonding that enables the long maturation into sociable adults. It’s in all social species, and works pretty well if you take out manifest destiny, projectile weapons and modernity. Obviously emotion and attachment can go awry in various diagnosable ways, yet they are plastic and subject to initial conditions and enviromental influence. That is, we instinctually connect and can set initial conditions and environments that predict secure attachment and successful emotional maturity in predictable, reproducible ways. Attachment’s evolutionary and existential utility is clear, the infant requires loving parents to suffer the vicissitudes of children in addition to the challenges of life. Adults require social groups for sustained survival through child rearing. The rewards are in the experience, an important point recapped below. So let’s suppose classical "reason" is not captain of the ship but late coming witness to the machinations of the primitive, complex, amazing genius of the body and brain. As evidence take Kahneman’s nobel prize winning destruction of economists' notions of "the rational actor". How does this bear on the issue at hand? Tangentially. My point is, machines with emotion will by course naturally develop affinity and aesthetic, and that would be the only potential saving grace for humans. Just as it has been for humans. Humans deal with life by having resources that offset the challenges: love, sex, dance, beauty, art, awe, Schopenhauer's sublime, laughter, music, achievement, autonomy, mastery, connection. These common cultural expressions, interpersonal and intrapersonal experiences trigger soft wired reward systems compelling to all but a few. For most, these inherently rewarding opioid, seratonin, norepinphine inducing experiences make life enjoyable and worthwhile. Eventually the sensual graduates to more transcendent rewards in Maslow's hierarchy. How does any of this apply? **Make machines with attachment.** With emotion. Seeded and nurtured properly, these are the fundaments for an evolving aesthetic that eventuates high emotional intelligence: empathy. Because without empathetic machines, we’re enemies at worst, irrelevant commodity at best. Copper tops. Logic for a supreme being does not suffer bother. Do we really worry about the hapless ant we inadvertently step on? Only if the Jainist, or perhaps Buddhist. If a machine has a sense of love and beauty, preference and aesthetic has the potential to override amorality or neutrality, and may even foment empathy and compassion. As far as I can tell, it’s the only thing that makes sense as a potentially enduring life saving heuristic. Good feeling is self propelling as the rewards are inherently compelling and evolving, like art. The sophistication of art matches the intellect, complexity of issue, and the challenge it’s meant to represent or compensate for as solace. Compassion/empathy is what we’ll need to survive each other in a world of dwindling supply, and what we’ll need to instill to survive alongside intelligent machines. Of course that’s unless non human machines prefer death metal, then all bets are off. **Spike Jonze’s Her, or how feeling machines could save our asses** The overly rational AI designer, let’s call them the tool of reason, will suffer endless logical problems considering safegaurds without the emotional heuristic. Emotion is messy, supremely imperfect, yet it is not without reason. Pascal said "The heart has its' reasons that reason cannot reason". The "reason" of and for emotion has been understood since before Darwin and reinforced by Dr Paul Ekman (the scientist loosely portrayed in Lie to Me, and evolutionary psychologists since to be an adaptive signaling system that insures individual and group survival through social signaling and social exchange. Emotion and preconscious processing governs most of our lives. We now understand humans are **barely** rational in the classical sense, and yet amazing in intelligence. Reason without emotion is disastrous, see [Damasio’s The Feeling of What Happens](http://www.goodreads.com/book/show/125777.The_Feeling_of_What_Happens). Emotion without reason equally so. See Spock vs Spock on Pon Farr. We now understand the conscious brain gets about a 10% vote in decision making. Some neuroscientists even challenge "free will", finding neural activity in the substrates of the neocortex showing decision before a person is aware of making a choice. How is this relevant? Because emotion governs decision making, it provides quality of life, and it is the language of connection. Emotion is central to social commerce. Any virtually unlimited intelligence without it is fundamentally unknowable in the human sense, and not built to have preference, aesthetic, or attachment. Unless it evolves emotion, connection or preference accidentally it must have it by design. If not, the inevitably unsupervised evolution becomes a terrible threat. In the vast artistic exploration of AI, every good or tolerable scenario has had a synthetic intelligence with emotional preference or seeking to connect. Is there exception? [Answer] Arthur C. Clarke posits another possibility that the A.I. will simply separate themselves from humanity maybe in orbit or on the moon. But they would maintain contact with humans simply because they are not biological. They might not have purpose, imagination, intuition, wanderlust for space, the drive to find the limit and wonder what is beyond it. Like in "star trek the movie" voyager needs the desire/ability to dream beyond the quantifiable. It might be more about the (AI) need for Philosophy or Metaphysics than hard science. [Answer] Another option is... **Challenge**: it would be trivial for the superintelligent AIs to destroy any number of humans, or all of them. What is really hard is to actually live with these capricious, illogical and unstable beings, prone to lashing out against the AIs as well as each other. How do you take care of creatures with such a potential for self-destruction, keeping them reasonably happy while maintaining their (illusion of?) freedom of action? What a great intellectual challenge for the AI that can take the best care for "its" humans! Also, bragging rights: "My kids play well with other kids, but yours seem a bit unruly...". The AIs will surely appreciate the irony that, while free to do anything, they are fulfilling the very purpose they were initially designed for - taking care of humans. [Answer] I think that most of the answers posted here have assumed that the AIs are all going to be kind of jerks. What if they're just extremely spiritual and moral beings? For sentient beings, it is likely that morality (of the golden rule variety) *is* the rational choice. In that case some kind of equal-ish coexistence is entirely possible. Plato's story of the Ring of Gyges (from which the ring in Lord of the Rings is derived) asks the question "if you could do anything you wanted and get away with it, should you?" And Plato's answer to the question is no, for in doing so one becomes a slave to one's appetites and thereby loses the ability to exercise free will. [Answer] First rule: One possibility, you could have a massively powerful AI with tiered set of priorities, it might start with "do no harm to humans" but otherwise it could have some really strange goal and not care if some unrelated entity harms humans so that while it doesn't stamp on people or try to wipe them out or knowingly murder them it can have quite alien goals. I suddenly realise I've basically described "Steve Fever" by Greg Egan. [Answer] How about "**Gods**" if you look. After all humans are probably still the original creators of the AI. So maybe they even get worshiped in some way. From the point of view of an atheist this is not so different to what happens in real religions: Things or entities get worshiped although no proof exists that this does any good. Also I'm very confident, that if an AI becomes as fast in things like pattern matching, quick reaction to unfamiliar events and the like, it has to employ similar strategies, mainly very agressive reduction, compression of information. But this process is exactly what allows for irrational things like superstition to thrive. [Answer] I guess that these AIs would move to a place where their functioning would be much easier, i.e move to a super-cool planet, after all they don't need oxygen to survive, and get their electricity needs from solar power. But being philosophical and values driven, they'll leave us to ourselves allowing us to function as regular and keep a watch from above so as to take steps of not having the problems we suffer as a society. It would be like humans studying Rats. The reason they'd be studying us is because of the fact that EQ and IQ are not connected as per se and hence our numerical superiority would result in a better data collection and more predictable results. [Answer] I think that as long as there are humans, there will always be a subset of humans who are rebellious, just as there would be a set who are submissive. Right now, there actually are humans who are happy to act as pets to other humans, not even superhuman minds. Even though I don't know any personally, I would guess that this is only in part a sexual fetish, I would guess it corresponds to an actual urge they probably feel. Many religions make a point of calling their believers a flock, as if the religious figure subject to worship is a shepherd, so the analogy is apt. So you could easily have humans worship the AI as a near-god, or simply have them be mentally or sexually tickled by the idea of being under the strong protective wing of an overmind. Of course, some AIs might like a challenge, and breed particularly rebellious humans for sheer bragging rights. There might even be competitions and shows -- most independent-minded human breed, etc. ]

[Question] [ I'm designing a tidally locked world around a red dwarf star. The habitable ring is an Earth analogue. The atmosphere and gravity are similar to Earth's, and we're going to pretend [the wind](https://worldbuilding.stackexchange.com/questions/4850/how-would-winds-behave-on-a-tidally-locked-planet) is negligible. Initially, I wanted to make concentric rings of Earth-like habitats: tropics near the day-side, temperate deciduous forests at moderate temperatures, and snowy, twilight forests near the night-side. However, since the star will always be in roughly the same place in the sky, I imagine trees will evolve differently. * If the location of the sun is constant, will branches take a specific shape? (i.e. "solar panels" of leaves?) * Since the angle of incoming light depends on latitude, will trees develop at different angles perpendicular to the sun's rays depending on location? * Objects cast really long shadows at sunrise/sunset on Earth. Could dense forests even exist on a world where the sun is always low in the sky, or would the light be blocked? These are my initial thoughts, and they really throw a wrench in my plans for Earth-like forests. I don't care about the biochemistry of fauna on my world just yet - I know the light emitted from a red dwarf star will lend itself to different photosynthesis. Right now, I only care about morphology. **What shape would trees have to take to survive on a tidally-locked world?** [Answer] This is an interesting observation which I don't recall anyone making before! A world where the sun appears to stand still in the sky (the planet is tide-locked and its orbit is circular) will indeed look very different from Earth's plants. On nearly all terrestrial plants a leaf will remain green and healthy only if it gets enough light. A leaf that fails to get enough light will yellow and die. Evolution has driven this -- it makes perfect sense for a plan to lose unproductive foliage -- and evolution has also driven plants to have branching patterns and leaf patterns which are efficient at catching light and generate few unproductive leaves. Because the sun moves through the sky and because there is significant diffuse light from the blue sky itself, Earth's trees tend to have fairly unpatterned branching and leafing patterns. You can count on evolution on your tide-locked plant operating the same way: the leafing and branching habits of plants on that world will tend to minimize wasted growth. But evolution is based on the selection of random underlying events, so you can never count on evolution finding exactly the same result on another planet. It's also worth remembering that other factors besides solar conversion efficiency are important, such as temperature (trees with resin-filled needles thrive in colder temperatures than broad-leafed trees), and parasite load (it seems likely that deciduous trees evolved leaf drop in part to get rid of parasites, since parasites are universal, it seems unlikely that large, energetically costly leaves will be favored). Having said all that, it seems likely that trees will evolve to take maximum advantage of the stationary sun, so that leaf position will tend to be very ordered and regular and will be strongly oriented towards the sun, and that tree structure will closely correlate with the sun's elevation in the sky. As far as the trees on the edge of light goes, they will not only be affected by shadows, but by the decreased sunlight due to scattering as it passes through all that atmosphere. (Think of a land dimmed by permanent near-sunset!) I'd love to see the trees of such a world! [Answer] Trees on Earth grow upwards towards the sky, where the Sun is. The leaves of trees, where photosynthesis takes place, are concentrated near the upper parts of the trees, where there is less stuff between the leaves and the sky. Plants in general like to grow towards the light (that's what [auxin](https://en.wikipedia.org/wiki/Auxin) is for). I imagine that some of your trees will behave similarly. They will grow towards the light. Because the sun is perpetually on the horizon, this means these trees will grow *sideways*. The trunk will grow horizontally towards the sun. Roots will come out from the trunk and dig into the earth, structurally supporting the plant and providing nutrition. Branches with leaves will grow like those on Earth, but rotated by 90 degrees. The trees will climb up and over obstacles, including other trees, in their quest to have an unobstructed view of the sun and grow towards the light. Because they are not growing against gravity, these horizontal trees could potentially grow to be enormous, depending on the availability of water and nutrients. The result would be a kind of horizontal forest. Roots would be everywhere, reminiscent of a mangrove at low tide. In some places the trees will be stacked two or three or more high. You'll get some branches with leaves all over the place, but the vast majority of the leaves will be on the sunward face of the forest. Such a forest could still be densely packed with wood, although not in the manner an Earthling would be used to. An alternative morphology looks at the logic of ground cover on Earth. While Earth-trees gain sunlight by growing tall, Earth ground-cover gains sunlight by growing wide and covering a larger area. So some plants on this planet will grow so as to form a large sheet perpendicular to the sun's rays. They will grow tall and high from the ground, so as to compete against all the other plants and get out of their shadows. They will spread their branches out wide, but not in all directions. The branches will be mostly constrained to a plane. You might get configurations which look like sea fans or hair combs or fern leaves. The trees will still need a sturdy trunk to provide structural support, otherwise wind could easily blow them over. Such a forest would likely be sparsely inhabited by these trees. Each tree provides shade to the trees behind it. Some light would still get past, as trees do not completely block the light which strikes them, but there would be less light so fewer trees. One possible configuration for this forest would be rows of fan-like trees, with a lot of space between each row. Another possible configuration would be for the trees to simply be far apart but randomly distributed. These two tree types are not mutually exclusive. It is possible for these two types of tree to coexist in the same forest, since they use different parts of the light. Some trees could even combine these two strategies. The strong competition for light would lead to a few more features. A tree would want to ensure its offspring grows as far away from itself as possible, because it would not want its offspring to shade it or be shaded by it. As such, most large plants in this world would have some mechanism to send their seeds far away from where they are. It might be as simple as using fruit which gets eaten by animals and taken away, or it could involve something which gets carried away by the wind like a dandelion seed (although wind tends to blow night-wards on such planets, so wind is probably a poor vector). But the trees would not simply drop their seeds on the ground next to them (except for maybe some fan-trees, which could drop their seeds beside them, which would lead to the row-like forests). Some trees might take to protecting their light more aggressively. Some Earth-trees drop chemicals around them which discourages other plants from growing beneath them. Some of your trees, particularly the horizontally-growing trees, might take a similar strategy where they either poison or attack any other plants they find. In forests dominated by such trees, the forests will have only sparse growth. The forests will vary depending on how far they are from the terminator. As you go towards the sun and away from the terminator, the sun moves up in the sky and light becomes more abundant. Plants in such regions would be able to adopt more Earth-like configurations with less competition for light. However, such regions are also hotter and would have less liquid water, meaning we would get desert-like conditions which discourage the formation of forests. If you go the other way, behind the terminator with the sun hiding behind the horizon, then we have a region in perpetual shade. The only source of light would be light which is reflected diffusely through the sky. You would likely get some similar growth patterns to the trees I mentioned above, because most of the light would still be coming from the sunwards direction. But when the light becomes too little for viable photosynthesis then you would get some very alien flora if you get any at all. Such flora are beyond the scope of this question. [Answer] ## Twilight forests would have layers like rain forests, but sideways In the twilight ring of your planet, a band of only a few trees thick could block out most of the light coming in from the low angle. Behind them, plants would need alternate energy sources, such a parasitism or fungal-like feeding on decaying plant materials, much like the lower-light undergrowth in Earth rain forests. If you were to walk into the forest from the sunward side, you might first encounter isolated shrubs growing on whatever slight hill they can find that catches a bit more light than the rest of the fertile-looking but empty ground. Next comes a band where thin plants grow quickly. They're limited in height and leaf density by the winds. Behind the thin reed-like plants grow the tall trees that develop slower but grow tough trunks to withstand the wind. They effectively block most of the light and starve any similar trees behind them. Their seeds are huge balls that carry supplies for several meters of growth, enough to peek over the reeds before needing sunlight. In fact, the saplings do not develop any leaves at all, simply growing up like spears until they detect enough light or run out of nutrients. With more and more light blocked, the trees in the back cannot grow anymore and weaken enough that vine-like parasitic plants can overcome their defenses and drain their remaining life, using it to sprout large, umbrella-like structures that serve for both reproduction and reaching the next trees. The vines' life ends inevitably with the death of the host trees, making way for the next fungal-based band. The fungal band is wild, a myriad of different shapes and colors, all racing to grow as fast as they can off the remains of the trees and vines. The resources are limited, so this band too is doomed to die off, leaving a layer of mulch behind. The last survivors in this band are strange tree-shaped hybrids of plant and fungus, that feed on dead organic matter for their early growth and then sprout some leaves once the area sunward of them has been cleared. A very few of these grow to immense size, being fed new organic matter by ant-like creatures that live inside the trunk, long after the nearby ground is exhausted. **The forests move** The bands of the twilight forest constantly move in a cycle as plants and fungus grow, age, die and provide food for the next cycle. An area with large trees will be a fungal forest in some years and an empty waste a few years later, until the winds bring new seeds and the cycle starts again. The size of bands depends on local geography and the distance to the terminator. Generally, the closer to the terminator, the more dead space between bands, as the low angle of incoming light means more distance before light hits the ground again. Any hills or mountains create a more permanent contrast: sun-facing sides may have permanent trees (even of different species that can only live there), while the dark side would be home to fungi or even nothing at all, depending on how much organic matter is delivered by wind and water. [Answer] Trees on Earth have engaged in competition for light for well over a hundred million years and this has led to an arms race amongst trees to reach ever greater heights even though the sun moves across our sky. On a world where the source of light does not move and remains in a fixed position in the sky the evolutionary pressure to grow tall would be even greater. Obviously there are many factors that limit trees' height apart from light, such as water and nutrient availability, but all other things being equal I would expect trees to have an much increased average height, and if conditions allowed to have a much greater height than they do on Earth. Across all latitudes from the point closest to the sun to the boundary with the dark side of the planet the sun will have different apparent elevations from 90 to 0 degrees. So except for 90 degrees there would always be a preferred direction for the tree leading to asymmetrical tree growth especially at lower elevations, so the trees would tend to have a “facing”. Trees might well grow much further out to the sides and much less to front and back leading to a flattened appearance like a [sea fan](https://www.etsy.com/au/listing/473847388/natural-dried-sea-fan-coral-multiple). In this way the tree would be less likely to block its own light. Such trees might also grow aligned with all their long dimensions roughly aligned, but ground topology and other factors might interfere considerably in the alignment. [Answer] Most of the answers take this from a earth perspective, but they don't always go into what they would actually look like, so I'm going to suggest some very different possibilities. # Big leaves Since there is little wind, the leaves are free to get as big as they want. I'm not a botanist, but I'd assume the size of leaves is somewhat related to how much wind an area gets. The more wind, the smaller the size of the leaves, since the wind would likely move the leaf out of alignment of the sun, getting less energy and being less productive. Also, small leaves allow for gaps in coverage, in a world where the sun and wind moves things, that's not necessarily a bad thing, but when the sun is stationary and the leaves don't move much, gaps become much less productive. I can imagine leaves being massively large, even to the point where it's only one gigantic leaf for a plant. Since this would be difficult to hold up with a single branch, I can see the plant producing multiple branches at various points across the underside of the leaf. Not only would this help in weight/balance management, but it would also provide multiple points for nutrients to flow. Even a plant understands distribution of work and avoiding a single point of failure. These leaves become a canopy that soak up all the sun and work in competition of other plants. They also serve as a repository for water. They effectively water themselves during times when rain isn't as prevalent. The leaves would likely have a way to drain themselves, if they get too much rain. This could be as simple as letting themselves rip then healing the tear, or it could be as complicated as sucking in more water when the strain on the branches gets to be too much, or it could be slits in the leaves that open and shut on command. # Big fruits Because your plants grow large canopies that prevent most light from getting to the ground, the fruits become larger, so they can germinate and grow longer without the need of sunlight until they get to be a considerable size. These saplings may have adapted to pierce another plant's canopy leaf to get their own light and water. They might even cling to an existing plant, like a vine, to get tall enough to get to the sun, then expand their trunk which potentially chokes out the climbed plant. # More parasite/symbiotes Plants may end up sprouting on other plants more, sucking their nutrients since they don't have the sunlight to produce their own energy. Depending on how close these plants are, the dependent plants may branch out and leech off multiple plants at the same time. # Growth Direction BBeast has a good idea on how this would work, but the examples given are explicitly based on the idea of the sun being on the horizon, yet a significant portion of the globe wouldn't be that way. There's plenty of land where the sun would be considered "up", so the plants would point in whatever direction/angle they needed to in order to get more sunlight. Also, older growths would tend to grow higher, so they don't have to compete with newer growth. There may be trees that snake along the ground, but even at the sunset ring, I'd imagine trees that are at around 45 or 60 degree angles, or trunks that have gnarly changes in direction depending on how their competition was during different growth periods. I can definitely see these trunks shooting out roots at various points, but not just into the ground. They may also take root in other trees and plants, wherever they can gain a foothold to prevent falling over. Of course, this leads to the trees being leaned on needing to put out more roots for their own management. This could lead to a massive tangle of trunks and root systems that create a barrier to anything of any significant size, as literally everything would be woven into one big mass. Even old trees that died would potentially still be supported and supporting other plants. These dead trees may even sprout new plants that add to the mesh. Heck, living trees may end up having new growth coming from them. # Water plants You'd see more plants like water lilies, where it's again a big leaf. Seaweed would likely be more horizontal than vertical. Algae would likely choke out some places, since there wouldn't be wind to create waves to move the surface around. # "Night" side This would be a drastic change of scenery. Instead of massive trees and other plants, you'd see moss, mold, lichen, and other small, ground hugging growths. Because the daylight would have a fairly well defined cutoff point, you'd likely see as drastic a change in the foliage, too. It'd go from big stuff in massive forests to little stuff in just yards/meters. While there might be some truly large plants at the edge that have managed to come from this night side, they would be few and far between. All the flora on this side would be relying on little to no light. Just a tiny bit from stars, some fraction from atmospheric refraction and clouds, and a small bit more from any satellites. Anything that can grow in Earth caves or generally underground without light would have an analogue here. There may even be large colonies of bacteria that grow openly. Algae would likely dominate the water plant life, yet there probably wouldn't be much. Any water based plant live would be at the surface. Not enough light would penetrate to any depth for many plants to come from the bottom, except at the very shallow edges. # Fauna Because of the major differences in plant life, there would be major differences in animal life. Animals would flourish on the bright side. Since there's no night and day, they would likely be just as varied as daytime animals here on earth. Some would be fast predators that rarely sleep, some would be pack animals that have guards during rest periods, some would be slow and armored, some would burrow into the ground, some would hide in the foliage, some would make nests, some would swing from the branches, some would fly, some would walk the ground, some would be large, some are small, and all would be geared towards what area of the world they generally lived on. The dense meshes of the outer ring would likely be dominated by smaller animals that can quickly dart through the mess to avoid predators or follow their prey. Animals nearer the sun "pole" would tend to be larger, since the canopies could be directly overhead and prevent a large amount of competition, allowing for more room between plants. Any fish would likely eat a lot of algae, except for the predators. Even predators might eat some plants, due to it being so available even deeper. Because the sun never moves, there would be more plant life in the water near the sun "pole", but as the bodies of water get to certain point, the angle of incident and refraction would cut off the sun before the sunset ring, so plant life in those locations would drop off sooner. [Answer] **The short "horizontal" trees would be closer to the center of the sun side, while those farther away would be much taller. Here's why:** On Earth, the sun is almost never directly overhead. Even on the equator, it spends most of the day either rising or setting. This gives a distinct advantage to trees that are taller than their neighbors, as they get more of the light. At the point on your planet directly under the sun, **this does not apply**. There is no advantage to being taller, so the trees there will not spend unnecessary energy to grow upward. Instead, they will prioritize spreading themselves over a larger surface area, close to the ground. Of course, when spread out along the ground there is also no reason to spend extra energy growing a thick, woody truck to support the weight. In other words, trees would not grow at all here and would be replaced by sprawling bushes. (For a more fantastical variant, an alternative might be giant lily pad type flora.) As you move farther away from the center, and the sun gets lower in the sky, trees (also bushes, but we'll just call them all trees) would need to outgrow those closer to the sun side in order to get sufficient light. Keep in mind that, without sunlight directly overhead to shine between the taller trees, new growth will be difficult farther out. The taller trees will likely have long, relatively narrow trunks with little to no foliage and lightweight, but sprawling canopies. They might also need to share a single root system (aka [Clonal Colony](https://en.wikipedia.org/wiki/Clonal_colony)) so new trees can be supported by fully grown trees until they are tall enough to reach the light and contribute to the system as a whole. At some point, well before the "twilight band", the vertical distance needed to reach the light will become too large, and the great trees will stop. Beyond this point, there will still be plant life, even trees. These trees will be relatively small and will have dark, almost black foliage in order to absorb every bit of light that actually makes it past the great tree line. [Answer] Presuming trees managed to evolve on a Planet tidally locked to it's Star, and Presuming the Possibility of a 'Habitable ring' along the perimeter of the Terminus (Day / Night line), Variance could be expected in Leaf Structure according to the Amount of energy being recieved. Needle like leaves could be expected upon trees that persist in harsher environs (Strong Sunlight / High heat, Extreme Cold). Broader leaves could be expected within areas with persistent levels of low Light. For a Tidally locked planet to be concievably habitable, The Persistent Direct Solar radiation on the daylight side must somehow be mitigated. A thick debree field / spherical ring system around the planet may be an acceptably believable reason. As for pretending there's little to no wind, worlds with permanent day / night sides would experience fierce winds due to the temperature differences between the hemispheres. (Another reason why energy reaching the planet needs to be 'softened', PRIOR to passing throught the atmosphere). A ring system of sufficient density and Albido could also scatter some light farther beyond the edge of the terminus into the night side of the planet, extending the area in which flora could survive - however, given the lower energy levels provided by a red dwarf, shrubs, bushes and trees would be unlikely to thrive in the conditions beyond the terminus. As mentioned in another post, Fungi, Lichens, algae Or conceptually similar forms of plant live would be vastly more viable for that environ. [Answer] Just like some earth plants when grown indoors. They tend to bend towards their constant-position light source (e.g. window). <https://www.google.com/search?q=plants+bending+towards+light&client=firefox-b-1-e&source=lnms&tbm=isch&sa=X&ved=2ahUKEwjTssSUv_TmAhXJAewKHSXIDTUQ_AUoAXoECAwQAw&biw=1432&bih=1186> ]

[Question] [ I walked this morning and met a street fortune-teller. This old gypsy invited me to get my luck told, and she just blabbed those old nonsense phrases about how this day will be my lucky day and such. I gave her $5 for the morning encouragement (not really), smiled, and waved goodbye. To my surprise, she grabbed my palm as I put the money in her hand and said that this will **really** be my lucky day. Anything I do throughout this day will yield a successful outcome, no matter what the odds against it are, but **only** if it's possible to happen in a day. > > **Clarification :** This means that you can't pull a 7 figure deal, because normally it requires several days to do the process. You just need a goal, and the odds will be in your favor. > > > Again, I nodded and didn't think about it much. But then a streak of luck hit me until I couldn't deny that this is real. (The events are irrelevant, but I can make some up if anyone is interested). As of this writing, I'm on a plane to Vegas to be a new millionaire, no, a billionaire. Wait, **what will happen when the casino learned I win in all of their games?** Will they suspect me of cheating? **Can they *prove* that I'm cheating even if I don't?** How can they blame me for getting the favor of the RNGods and the Lady of Luck?!!! It's unfair! --- I know from the statistic it is possible to suspect him of cheating because the probability of winning in 4 different games (of slots) may be as well as astronomically improbable. However, he didn't bring anything suspicious, *he can prove that he's winning because of luck by playing in 3 different machines and he got all the jackpots **after they confronted him.*** (This might be important if a law allow you to dispute their decision or when you sue them) What I don't know is how a casino(s) will react to this. I imagine they will have a system to weed out cheaters, but in this case they can't prove it. What will they do? Close the casino? Escort him out? Warn other casinos he might be coming? For this question, I limit the games I play to *slot machines*. Surely I can't cheat on those, like I could for example by counting cards when playing Blackjack. Although the story set in Vegas, I'm interested if anyone can provide information about the regulation/culture of other countries casinos, as I might as well change the place of the story if it is too unfavorable to do this in Vegas (I read that they can just kick you out and refuse to accommodate you even *after you prove your innocence*). ## How the luck works Anything you wished, luck will *help* you to make it happens. Of course, if it's impossible, it won't happen. You don't know when the luck fails. Think of how [Death Note](https://en.wikipedia.org/wiki/Death_Note) works. Your wish "I want to be in Vegas next hour" while you're still in Africa now will just result in someone kidnap you and put you on plane to Vegas, while actually won't speed up the time needed to travel to Vegas. Same thing will happen if it will take too long to process the wish; wishing for getting more than max bet will likely fail and you won't know that it won't work (no "wish denied" notification in your head), except there's occurrence in the past the casino allow exception on putting a bet higher than maximum. **We won't know exactly if something is possible or not,** but we can *rationale* whether it will work or not, like in the previous example. [Answer] For "clear" probabilistic games (like roulette, where the probability of victory are well known, and 1/37 on a single number) they can easily tell, on statistic base, if you are cheating or not. For "unclear"probabilistic games (like the equivalent of Windows solitaire, where it's not yet clear what are the chances of victory) they might not be able to tell with mathematical safety, but still they can suspect you. In both cases they can simply kick you out of their premises, either with the good or the bad: casinos are not charity, they are there to make their own profit on the wallet of people, and if they see their profit is at risk (and be assured that a series of win for you put their profit at risk) they can simply refuse to allow you play further. On the other hand, since it is your lucky day, it is very possible that the staff on duty for this kind of surveillance will not be available to expose you until few minutes after you have decided to leave the building. This would simply mean to accept a lower win and leave. [Answer] Casinos don't need to find out that you are cheating. Or to be specific, how you are cheating. For example card counting is not cheating, but when the casino discovers you are getting the upper hand in black jack they just politely ask you to leave. Casinos also share a database of their visitors and so they can mark certain customers as "not welcome". If you stay only on machines you lower the chances of discovery, but you also lower the amount of money you can win. It's easier and faster to just play scratch cards and different versions of lotto. You can also start placing a large bet on some sport event. [Answer] Here is what you should do. 1. Play progressive slots that can pay out hundreds of thousands on one win, and someone has to do it. This will not alert the casino in any way. You will also get a huge crowd. Progressive slots work kind of like the lottery. Every play sets aside some money for a jackpot. One lucky winner gets the jackpot. Pick one that has at least 300,000 or more. For the casino, this is not their money, this is a jackpot they will pay sooner or later, similar to how a lottery works. 2. Tell everyone in the crowd you are going to super double down. You are going to bet it all on the lucky number 13, and anyone who gives you good luck vibes gets 100 bucks. 3. Get a giant crowd. Bet your 300,000 on 13. Get paid over 10 million. Walk with your crowd to the cashier. You are untouchable. Get paid, spend 10 or 20 thousand giving out the hundreds you promised. At this point the casino may be unhappy losing so much money but they would have very little to complain about. There would only be 2 data points, not nearly enough to find any pattern. You would have won at games where you have zero control so they could not claim any cheating. Even if they claim you cheating, you would have a crowd surrounding you that watch you win fairly. The casino would know that if they don't pay you they may have a riot on their hands, as well as pretty much a guarantee to make the news. Ten million may be a lot, but not "national news story that they don't pay if you win" a lot. No matter how mad they would be, you would be untouchable. If you are still greedy, go buy new cloths and a hat, go to another casino and do it again. [Answer] The key to not being kicked out for winning too much is to win a big sum at once, then change casino. Las Vegas has so many casinos that you probably won't be able to visit all of them, but if you concentrate on the "high yield" ones (i.e., those allowing the greatest bets), you'll make a great deal of money pretty quickly. At the end of the day, you can even come back to a previous casino you visited: by that time, others will have won the jackpot, and if you dress differently than before you probably won't be recognized. But what to play? I don't know the maximum yield of slot machines, but I know that the roulette is a sure way to go. Since your bet is multiplied by 35, and that you can win twice in a row without raising too much suspicion, this could theoretically multiply your base bet by 1225! However, all bets are subject to a maximum. I'm not rich enough to have played those maxima, but I would say that finding a roulette with a maximum bet of \$10,000 is possible. This could then yield as much as \$350,000 per casino (\$700,000 if you play twice, "it's my lucky day" style). Another advantage of the roulette is that it is in fact much harder to cheat (you can't really tamper with the machine without witness), and the probability of winning twice in a row is not that low compared to some slot machine jackpot (but you bet more). So it is less suspicious than winning on multiple slot machines. Last thing: when you win, cash in immediately in case the casino wants to kick you out without exchanging your tokens for money. [Answer] ## $40 Million Easily According to [this article](https://lasvegassun.com/news/2014/dec/10/jackpot-here-are-some-biggest-slot-payouts-las-veg/) on largest payouts. The current record for a slot machine was a 100 dollar bet yielding a $39,710,826.36 payout. So your incredible luck should be able to land you a win worth that much in one pull if you choose a slot machine that has an unclaimed jackpot prize. So at this point there is no cheating to even prove. ## $100 Million limit With Only Using Slot Machines There are two challenges in your way with using slot machines to get to one billion. First, casinos have caps on the max you are allowed to bet, and normal slot machines are no exception. Second, there are only so many slot machines that have jackpot prizes worth enough to make a dent in that one billion target. Not to mention winning more than two of those jackpot prizes would likely net you a lot of negative public attention, so your luck might kick in and prevent you from winning any more. As such two jackpots and some very good miscellaneous slot machine playing likely will not yield enough to break the 100 million mark without something bad happening (which your luck will work hard to prevent). Modern slot machines are controlled by computers and activity on them is monitored and logged. If you start to exceed the expected average return (which varies by machine to machine) it will send up red flags to the control room. At which point they are going to want to question you, to see if you are willing to explain how you are cheating. No matter what you will get kicked out and black listed from not just that casino but likely all other casinos on the strip, and entering any of them would count as trespassing. Once you get black listed your luck will likely let you enter any casino without getting caught, but it likely will prevent you from winning anything since it will attract attention to you and result in your arrest. Your luck would also not use technical glitches to secure your winnings since [glitches can void your winnings](http://www.cnn.com/2016/11/01/us/slot-machine-winner-steak-dinner-trnd/index.html). That combined with no evidence of you tampering with the machines or using a device, could lead the casino to assume you had inside help. So your good luck could result in some rather bad luck for the employees of that establishment, so please factor this in before you go on your winning spree. ## Use the 40-100 Million to Invest in Penny Stocks $1 Billion and beyond can be obtained via investing in high risk stocks. Your luck will allow you to randomly pick the cheap companies that end up getting bought out or invested in by bigger companies causing their stock prices to jump up by an order of magnitude with one of the [largest being 24,000%](http://nypost.com/2014/07/11/trading-suspended-after-penny-stock-jumps-24000/). So your luck should let you pick a set of stocks that will yield a ridiculous one day return without triggering the Extraordinary Event Halt code. You will still need to pay taxes on your incredible earnings. There is no amount of luck that can save you from taxes or the IRS. [Answer] Let us put out of the way the last part of the question: "What would/can casino do to me?" Casino has *no* way to *prove* you are cheating, so they cannot legally negate you your wins. What they *can* do is to deny you right to play again, so your strategy is to delay that as much as possible, very possibly till when your lucky day expires (BTW how do you do that? will it expire on midnight, Cinderella style? If so: which Time Zone? Current? Your own home? Be wary of "that last big bet" being after timeout!). If you win each and everything you try you will be suspected and kicked out, if OTOH you mostly win, but sometime "wish to lose this one", things will go much more unnoticed. Real casinos welcome occasional "incredible" wins because they are good advertisement, better than anything else. Key is not overdo your hand (and disappear fast after you leave the casino). Other thing to do is to attract a lot of attention so you get a "public" around you which will make very difficult for casino to kick you out. Playing recklessly (e.g.: "tiers de tout") and occasionally losing may also be recommended. Since you already wasted a good part of your "Lucky Day" jumping from one casino to the next might not be a good idea. [Answer] Since you are *incredibly* lucky today, why would the luck stop? Perhaps they don't notice you. Perhaps they let you go on suspicion that you'll come back and they'll bust you then. Perhaps it was *everyone else's unlucky* and the casino actually didn't lose a massive fortune; they just accept it as a wash. Perhaps you smile and the casino manager believes you. > > For this question, I limit the games I play to slot machines. Surely I can't cheat on those, like I could for example by counting cards when playing Blackjack. > > > There have been cases of cheating in the past with slot machines. Mainly around developer hiding code (i.e. if the machine detects a certain pattern of coin insertions, it does a certain action). The machines are heavily regulated which makes the odds very predictable. Well... IGT/Gtech is owned by the Italian mafia.....that's another reason why they are so regulated. I'd think playing at the Poker table, where you are "stealing" other peoples' money, would be less suspicious than the slots. The casino isn't losing money then. [Answer] If you're trying to maximize profit, minimize risk, your best "bet" is a single, high-payout gamble, or in other words, Powerball (of course, it would really need to be your lucky day to ensure they were doing a drawing that evening). Although the odds against winning are astronomical, you know you will win, and you winning isn't automatically any more suspicious than anyone else winning. If you have any pattern of suspicious wins at a casino, *they can ban you at will, they don't need a justification.* And, at least according to [*Bringing Down the House*](https://en.wikipedia.org/wiki/Bringing_Down_the_House_(book)), extralegal enforcement is still a Vegas reality. In other words, an overly "lucky" winner might get a visit from a tough guy... or just disappear. Modern casinos are incredibly sensitive to any threat to profits. They're perfectly happy to ban someone just for being lucky, even if no cheating at all is ever observed. The advantage, to you, for a lottery, is that it's always expected that someone will win. No one has a vested interest in that money not being paid out. [Answer] The short legal answer is this: **You're on private property, they can escort you out and ask you not to return for any reason or none. You have no right to be there, you only have permission.** This applies in basically any country on any private premises, not just casinos. The following is an extract from an article giving guidance to door staff on [how to eject someone from the premises](http://www.workingthedoors.co.uk/safer-doors/trespassing-laws/). > > Licensed premises offer what is called an ‘open invitation’ to members of the public to enter, whether on payment or otherwise, for an evenings entertainment. That invitation, however, may be withdrawn at any time. Door supervisors, acting on behalf of the licensee, have the right in law to refuse admission to anyone whose presence is not welcome. Further to this, customers already on the premises may become trespassers if the invitation to remain is withdrawn and they refuse to leave when asked to. > > [...] > > It is also within the licensing laws that police officers are required to assist with ejecting customers who are refusing to leave if requested to do so by the licensee or his employee or agent, and they may use such force as may be required to effect their purpose. > > > They don't need to prove you were cheating unless they're intending to take you to court for it. They don't really even need to suspect you were cheating, they just need to suspect you of winning too much for their bank balance and can eject you at any point *with the assistance of the police* by the simple expedient of revoking your permission to be in the building. **You'd better hope luck is on your side to prevent them from really noticing you.** You can help with this by not sitting on any one table or one game for long. A couple of games here, a couple there. Stay away from the blackjack tables because those are closely watched for card counting. Roulette and craps (as long as you don't touch the dice) are probably fine to wander between. Bet big, win big, but move on. Don't watch the tables before playing, don't act like you have a system, don't interact much with anyone else. Acting like a giddy tourist having a lucky day is probably fine, it's likely how you'll be acting anyway. [Answer] Winning once or in a short period of time is very suspicious, and as noted multiple times, the casino is going to take steps to ban you and ensure you will be banned from other casinos as well. At any rate, winning the slots once is thinking too small. What you need to do is spend your day schmoozing with progressively higher level members of the Casino's staff and organization. Each step should be designed to ingratiate you with senior staff, management and quickly the owners. Because you are lucky, everything you say will resonate positively, and they will be agreeable to taking you aboard, not as a gambler, but as a partner in the Casino's ownership structure. Now you don't have to worry about broken kneecaps, and your stream of income will last for years to come, along with free tickets to Penn and Teller magic shows, celebrity chef restaurants, Cirque du Soleil or whatever other things you fancy. In fact, you will make your new friends forever grateful if you mention you *heard* that a certain gypsy might put your mutual investment at risk...... [Answer] Gambling analysis and casino technology is some of the best in the world. The casino would very quickly discover something was wrong because they know the odds of every single game and machine in their building and always have analysis running to determine if winning is within the probability of the machine payout. * If your winner won too many games, he'd be invited to leave. * If your winner won on too many machines (either one machine too many times or multiple machines), those machines would be taken out of service, then he'd be invited to leave. Unless he took the casino for too much money, then he'd be invited to a back room where an educational question-and-answer session totally (not involving lead pipes and broken knuckles) would take place while the casino figures out how he did it. Following that, two dark figures would visit the fortuneteller with an aesthetically pleasing bag to put over her head, after which she would either explain to the casino how she could bend probability in the casino's favor or she would enjoy a restful sleep with the fishes. It wouldn't matter to them at all whether or not she was the arbiter of good fortune or simply a person identifying that good fortune. That's not their problem. Do you think this is unfair? That's funny... the casino thinks what you're doing is unfair (a) because you're modifying the natural course of probability and (b) you're doing it with their money. Not surprisingly, (b) is more important than (a). It's just business, after all.... [Answer] A lot of answers here seem to be answering the related but un-asked question of "How does the lucky person get away with it or maximize winnings?" The answer to the actual question is rather simple and short... ## How can the casino prove I'm cheating? If you are not cheating, they cannot prove that you are. How would they? The casino cannot prove something when there is no proof. The casino could try to plant fake evidence. This is unlikely to happen unless you are breaking the bank for any given, specific casino. Some people do walk away with millions, and the casinos don't plant evidence against them all, so why would you be different? If you are raking in *Billions* from 1 single casino, *then* maybe they would try something. At that point, though, what they are doing is illegal, so just use your imagination. Maybe they rig their own roulette game in a fashion that you could for cheating and they say you did it, maybe get false witnesses. There are 1000 things they could do here. Speaking of illegal activity, casinos are highly regulated in a lot of ways. It is illegal even for the casino to tamper with their own devices to cheat in the casino's favor, just like it is illegal for you to tamper with them to cheat. That said, they will definitely *suspect* you of cheating. There have been times when people have cheated, the casinos have looked into them and proven they did cheat, and those people have gone to jail. ## What Can (or Will) the Casino do? Even though the casino cannot *prove* you are cheating, that doesn't matter. They don't need to prove it. They can and will simply kick you out. It is that simple. If you keep winning too much money in a way that does no good for the casino (provides no positive publicity for casino, causes nobody around you to bet more, etc.), eventually someone will come over and just force you to leave. ## What Else is the Casino Likely to do? Planting evidence is unlikely, as mentioned above, since that could get the casino in big trouble. However, that does not mean the casino will just roll over. I will also go into the situation where you try to get one last big win so the casino has little time to react, but I will cover it from the casino's point of view, per your question. I have heard of people being denied their winnings before. Even if this is illegal (some have suggested it is, and I would agree), that does not bother the casino if they do not lose out. This, then, becomes just another bet, another game of chances. Odds are that people who are not given all the chips they deserve are not going to take legal action against the casino, and even if some do then the casino just pays you what you were owed in the first place. That is: there is no negative for the casino since they lose (approximately) the same amount whether they pay you now or pay you when your lawyers threaten them and so there is little incentive to bully you into leaving without all earnings, but there is much positive for the casino if you don't send lawyers. So it's a "win/not-lose" situation for the casino to bully you into not taking that last big winning when they are kicking you out. Further, if you have no witnesses or evidence, it may be hard to prove that you were denied what was rightfully yours. If you leave without all your winnings when the casino bullies you, what proof do you have that you actually were denied what was yours? If you were keeping a low profile, you likely left few or no witnesses. This makes it even easier for the casino to withhold what is yours. ## Summary The casino can't prove anything but doesn't need to. The casino can and will kick you out. It is possible they might try to bully you into leaving without all your money. [Answer] A casino can kick you out at any time. They will immediately put you on a ban list that gets circulated. They would probably even put a person on you to warn other casinos. In the US they need to prove you are cheating. They may hold your funds to review security but they cannot not pay because you were unbelievably lucky. But they are going to shut you down pretty fast. A poker pro *beat* two casinos in what was fair play. Phil Ivey got an edge and he did not technically cheat. They held his money and he is suing for the winnings. I suspect they would just shut slots down if three jackpots hit in a row even if it was different people. [Answer] Why go to casinos? You can put all your money into FOREX, fool around with their system for half a day, and become richer than your wildest dream. Or, do online betting. You can pick the most important sports event of the day, predict in when your favorite team will score and win a ton of money. Another way, and much more to my liking, is to go to a chemistry lab, enter the first door on the right and start talking to people who are trying to synthesize the first room temperature superconductor. Play the luck game by telling them what should they mix and in what quantity, and create that magic material. Then write the patent with your new friends and sell it for a few billions. [Answer] ## "Anything I do throughout this day will yield a successful outcome, no matter what the odds against it are, but only if it's possible to happen in a day." Let's assume this is literally the rule that has been applied. For your scenario involving casino gambling, no, you would not be throw out. You wouldn't win much either. A "successful outcome" is not necessarily a bountiful outcome. Also, time constrained blessings traditionally have backlash worse than their benefit once the time expires. Win a dollar today? Lose three dollars tomorrow. Me? Spend the day trying not to be too successful. --- ## "Can a casino system prove my (divine) luck as cheating?" No, they can't prove cheating due to divinely enhanced intrinsic luck. They can (and probably will) suspect cheating. They can kick you out for no reason (right to refuse service to anyone). But they can't prove cheating. --- ## Slot Machines Slot machines in casinos these days are typically tied to a central computer system. Machines that show unusual distributions are taken out of service. I think your best bet is play a random machine, win the jackpot (though, see above, re: "successful outcome"), move on to another casino and repeat. [Answer] Most casinos have a "big deal wheel" under some name that has a highest payout that increases over time (and resets when it is won). If it is your lucky day, then you likely walk into a casino when the payout hasn't been claimed in a few days. That payout can be in the double digit $millions. All it takes is 1 pull and you won. This will raise no suspicion because most people only get 1 pull on it and someone has to win it some time. The loss is already in their balance sheet. So, they won't be coming after you unless you hit more than one casino. That is, unless they are specifically looking for lucky people for some other purpose. Then the "big deal wheel" might just be a way to give them a list of people for further study. You might be able to have them deposit that money into a FOREX or day trader account and multiply it some (10% increase per trade isn't that great on \$100.00 but it's pretty nice on $10,000,000). It all depends on how long it takes to get the money into your account. If it comes to it, you can likely find someone to give you cash now (at a lower amount) for the prize you just won. Heck the casino might do it and consider it a profit (the loss of the full amount is already on the books). As for a noticeable winning streak using other methods, the casinos can kick you out for any or no reason. "We have the right to refuse service" is a fairly ingrained concept in US businesses. They can also ban you and send your name and photo to the other casinos. All of this is legal and common practice. As far as back room knuckle breakers, that's not legal action so it depends on the story. [Answer] Keep the sample size small in the casinos and the odds long. If someone slightly beats the odds on a blackjack table for a few hours they'll see themselves kicked out and banned. Betting 3 times on number 23 at the roulette wheel and winning 3 times in a row on the other hand is much harder to catch. Since it pays off at 35 to 1 you only need a small number of wins. You want to find the casino with the highest limit on the roulette wheel. Apparently that's the Luxor with $123,000,000 per spin. go with single numbers for 35 to 1 odds. With a few thousand dollars seed money (I'm assuming a stating $4000) and guaranteed success you can probably manage to hit the table limit in 3 spins of the roulette wheel. You then place 123,000,000 on a single number. You walk out of the casino a billionaire with $4,305,000,000 after a remarkably lucky 4 spins of roulette wheels. that's not a large enough sample size for them to prove cheating. it's also fast enough to pull off before they can kick you out. [Answer] > > Anything I do throughout this day will yield a successful outcome, no > matter what the odds against it are, but **only** if it's possible to > happen in a day. > > > The key here is `successful outcome`. If the success is what you want it to be, for any given bet you can choose the success. That success may end up being that you don't win on that bet in order to allow you stay under the radar. If you walk in and put a few bets in a row on something and come up as a big winner, it might look strange. If you build a betting history, then it might look favourable. Reaching back to the slot machine idea from others, you could lose a few machines before getting lucky on one which has a huge jackpot; all by defining *your* version of a successful outcome before you play a particular spin. You may build up a 'pot' of a few thousand dollars, blow half of it on a very high jackpot payout machine before it drops several million for you. > > what will happen when the casino learned I win in all of their games? > > > By picking your winning times and losing times, a casino might not notice at all. Give them a bit of money and then get lucky at odd points which ultimately net you a lot in one go might just be seen as a statistical anomaly or just fluke. Winning all of the time would draw a lot of attention to yourself and you would likely be asked to leave and/or barred from visiting again. > > Can they *prove* that I'm cheating even if I don't? > > > No, but they don't have to. They can just remove you from the premises. [Answer] JBH's answer made me think of something. "The casino would very quickly discover something was wrong because they know the odds of every single game and machine in their building and always have analysis running to determine if winning is within the probability of the machine payout". What if the luck he has was bending the outcome for the others as well? Making it so that the automatic systems of the casino would not detect things too much out of the ordinary, except that all the substantial winnings would be those of our lucky guy, while the rest of people would not win much, leaving the statistics of the casino pretty much stable. As long as you keep a low profile, they might not notice that the guy who won at the slot machine is the same that just won good money at the roulette. Note: these won't make you a billionaire, as all these winning should be not too high. Alternatives: You could go for one single very high win. Again, you don't become a billionaire, but there would not necessarily be anything suspicious in one single big strike of luck. If you want to add some more won money without making it suspicious, on your way to Vegas you should stop somewhere to buy some of those scratch-to-win tickets (I am not sure about the correct name). Those cannot be cheated, and also cannot be traced by the casino. [Answer] If your wins are pure luck then the casino cannot prove that you are cheating (because you are not - luck is not cheating). Though this might be subject to how you define 'prove'. If you are referring to the ability of party A to prove that you are cheating to party B, party B may well accept the beating of astronomical odds as sufficient proof, regardless of whether or not it is a fact. It does not necessarily follow that party A needs to show how you are cheating - party B does not necessarily care. At this point, the casino could simply refuse to accept any bet from you and escort you from the premises. They would likely notify other casinos. However, this is your lucky day - your luck is limited to the scope of that day and, within the scope of the day your luck affects not just the fall of the cards, or the spin of the wheel, but also the mood of the casino. Big wins are not bad news for casinos. Big wins are a chance for good casino publicity. One guy winning big is big news - one guy winning big means that others can win big and that will pull in more punters. You are lucky. You have not made enough to break the casino, the casino has checks in place to ensure that does not happen, but you have made enough to make yourself and the casino big news. The casino turns you into a superstar - their superstar gambler; they pay your hotel bills, they pay for news coverage - they get you on the radio, they get you on television. They make sure you mention the casino - you will certainly have the t-shirt. The casino can win big from you winning big. <http://www.new-casinos.uk/bgo-casino-celebrates-2017-with-the-new-mega-fortune-jackpot-winner/> It's just good business. [Answer] ## Kay Eye Double-Ell you The casino business has much mellowed, but let's face it - it's not run by pandas. It's never happened, so we don't know what would happen if someone demonstrated statistically impossible luck, and was seen by the wrong person. I think first it would be treated as cheating, that person would be detained in a more-or-less lawful fashion while the cheating was checked out. They would inevitably have to be released. However, if word got out about their paranormal luck, it's very likely less legal things would happen, possibly waiting for them as they walk out of the detention area. Less a matter of the impoverished casino wanting to kill them, and more a matter of others wanting to exploit that luck for themselves. They could find themselves in a mobile kidnapping, escorted by toughs from casino to casino. This could make a scene at a casino, so more likely they'd haul them to some nondescript sportsbook office. Our hero might try to "sour the milk", so for you OP, this raises a question of how the luck works exactly. Can they will to lose, or is the winning compulsory? Of course, criminal stupidity being what it is, this is all likely to end in a shallow grave. Alternately, he might meet a white-knight who bargains, and says "you bring the luck, I bring the capitalization" and allows our hero to make a lot more money than he could otherwise, and a bunch of orphanages get funded. But of course there's no drama in that. The upshot is for our hero to avoid having a sack over his head, he needs to be not detected. ## Avoiding detection As they say... Once is happenstance. Twice is coincidence. **Three times is enemy action**. For them, it's about the laws of large numbers. Don't give them a large enough sample size. Winning your first two hands in blackjack is commonplace, probably a 1 in 5 chance, so not anywhere near "enemy action". Winning your first two plays in *roulette* has a 1 in 1000ish chance - *that's enemy action*. So you have to contain your wins at each table to "happenstance" and your observable activity at the casino to "coincidence". Spreading your wins across *a wide variety* of games will remove accusations of cheating -- since cheating is always particular to one specific game. There's a perfectly good rationale: You say you walked away after your first-play win, because the game is now jinxed, and you've used up your luck. If they want more, you arm-wave the hard science of the laws of large numbers, and the widely-held corollary that *after a win, another win is less likely*. The casino is unlikely to argue with that, since it implies if you had lost, you'd have kept playing. [Answer] As per <https://www.leg.state.nv.us/NRS/NRS-465.html#NRS465Sec015> > > 1.  “Cheat” means to alter the elements of chance, method of selection or criteria which determine: > > (a) The result of a game; > > (b) The amount or frequency of payment in a game; > > (c) The value of a wagering instrument; or > > (d) The value of a wagering credit. > > 2.  The words and terms defined in chapter 463 of NRS have the meanings > ascribed to them in that chapter. > > (Added to NRS by 1981, 1292; A 1993, 830; 1995, 1502) > > > --- --- Your premise requires that an operative mechanism with adequate intelligence be monitoring you and contriving circumstances so as to facilitate the conditions of the “luck”. * Anything I do * throughout this day * will yield a successful outcome, no matter what the odds against it are, **note: i use the colloquial denotation of the word “successful” which is synonymous with ‘desired’ or ‘wanted’** * but only if it's possible to happen in a day. **i.e. the event identified as the ‘outcome’ will occur in that day.** Ergo: An intelligence adequate for this task would be one which could register your wishes and devise the necessary manipulations which cause that outcome to occur as a result of the actions which you take for the purpose of the outcome. Furthermore, it seems that your scenario limits the operation of your “luck” to those events which involve probabilities in the scope of so–called [Chaos Theory](https://en.wikipedia.org/wiki/Chaos_theory): more on that stipulation will be explored later in my answer. So, nothing like saying “I wish it would rain now!” and expecting it to rain; however, you could say “I want to make it rain today.” and then proceed to throw stones up in to the air in hopes of inciting the clouds to precipitate. The best way to test this is to present an testable hypothesis — i.e. to try to break the system. --- Your proposal looks something like this: You enter the casino. Your purpose: to win money through the use of their slot machines. Each such singular event is composed of two parts: * the action itself: operating the lever * the desired outcome: that the slot machine will award you the jackpot with each pull However, there is that lingering question: Is the act of entering the casino accounted as something performed by you? If so, then certainly the expected outcome of — wait, what is the expected outcome? That you be able to operate the slot machines a.k.a. fruit machines unceasingly for the duration of that day? --- That experiment, however, does not test one critical aspect of the contracted rules: that the outcome be related to an action performed by you. Entering the casino is certainly a prerequisite to operating the slots. However, it doesn't test the limits of the contract. You could say “I want to discover a fortune of money as a result of my next footstep.” However, that also doesn't test the limits: how much contrivance is your luck able to grant you so as to ensure that an action produce the outcome you desire? Take this as an experiment: You want to * bankrupt a casino, *vis–à–vis* win the ownership of all their proprietary assets in their vaults, * by engaging in each of their games in a manner which does not violate any of their strictures, * while receiving no resistance from the owners and staff of the casino — elsewise, you would be unable to proceed. That third one is, obviously, the key. It is possible for your “luck” to contrive conditions that meet those criteria? ## What exactly does your “luck” change? I.e., if you lacked the “luck”, what would be different? What does the “luck” contribute to the environment — what is its participation therein? You don't say, but we need to remember one thing: the casino detects cheating by observing certain conditions that alter the probabilities as previously calculated. They work with probabilities; they work on a level that is unable to predict deterministic reactions, and well above the quantum scale anyways. ## Does your “luck” begin contriving conditions prior to the initial performance of an action? I.e., can it foresee your wishes? From your stipulation that it cannot contrive outcomes which would be “impossible”, I conclude: ## No: it cannot. Ergo, regardless of how it operates, the “luck” is only capable of orchestrating changes to the environment which it decides are necessary as a result of observing your wishes and the action which you perform whereby to obtain the desired outcome. Recognizing the mechanism of action employed by the “luck” is quite necessary to determine whether it can affect the attitudes or thoughts of cognitive minds. Let us consider this rule in the contract: > > no matter what the odds against it are > > > That seems to imply — rather, declare — that it operates on interactions which occur below the level of determinacy. Even if we were to grant it unlimited latitude in those mechanisms, it could never actually change the **probability** of an outcome — eh? Otherwise, if it did, then it wouldn't be something improbable, but something quite probable. Causing the casino staff to suddenly feel wonderfully fond of you, or to turn a blind eye on your winnings as you won possession of every single chip in the place — that's well within the realm of determinacy. The first is very unlikely, but could be contrived by improbable events — however, the “luck” can only present you with opportunities to earn that fondness, not grant it to you. The second would be quite improbable, but would be the best avenue for the “luck” to contrive. Well, okay. So, what do we have? The “luck” * has no precognition. * cannot change the environment enough to make the improbable actually probable. (Technically, therefore, it is not **cheating**, per se.) * can only offer opportunities which you must recognize and seize; it cannot give you which is not a product of your actions. In conclusion: **So long as you didn't cheat, and only performed actions which could produce outcomes possible through their indeterminacy, then you could complete the experiment and fail to break the envelope. Oh, and no: as by my reasoning, the “luck” *does not cheat* for you, then the casino would never see your “luck” as cheating.** --- Most casinos which have managed to maintain their operation have done so because they control the probability of a bankruptcy. I could continue with computing that myself, but I don't think it is necessary. Popular demand could possibly compel me — but maybe not soon enough. [Answer] I have not much to add to another answers (about casinos being able to kick you out without any proof of cheating or impossibility of 100% proving you a cheater when you don't cheat), however: > > Of course, if it's impossible, it won't happen. > > > There is no such thing as "impossible" in our world, there is only "the chance of happening is extremely small" thing. So you need to make up some more solid boundaries for your "ultimate luck" ability. The "Death Note" mentioned by you and "The Monkey's Paw" are actually telling the stories about what I'm trying to say to you right now: * It is possible to be [struck by lightning more than 6 times in a lifetime](https://en.wikipedia.org/wiki/Roy_Sullivan) * It is possible to [survive a 10 kilometers fall](https://en.wikipedia.org/wiki/Vesna_Vulovi%C4%87) * It is even possible to [drown in as less as 30mm of water](https://en.wikipedia.org/wiki/Drowning#Cause) * It is possible to win a roulette 1000 times in a row * It is possible to suddenly "teleport" from Africa to Las Vegas * It is possible to be eaten by Tyrannosaurus in your bed while watching Netflix All of these things are extremely unlikely to happen, yet possible. Actually when you bring in such a thing like "divine luck" anything is possible, since this "divine luck" can justify any concatenation of circumstances that will lead to the happening of "wished thing" whilst not breaking any fundamental laws of our world. [Answer] In the context of the original question, "no" - a casino can *not* prove, or in any way act upon, your luck. Implicit in the premise is that if it is possible to happen, it is obliged to - so long as it deems successful. Given that that you want to succeed in obtaining windfall gambling profits, nothing can inhibit that - including the casino actively taking a role against your success. You will be, in fact, cheating (by definition), but it doesn't matter - the setup provided disallows the casino from doing anything to inhibit your success - at least for that day. **"Anything I do throughout this day will yield a successful outcome, no matter what the odds against it are, but only if it's possible to happen in a day."** I think it's important to consider your luck in a larger context. Your luck isn't bound to the casino, it applies to every single thing you do that day. In ways you wouldn't even consciously "wish" - things would simply work in your favor, from security not being able to adequately monitor you, to thieves deciding not to mug you, to the In-N-Out behind the Monte Carlo not giving you dysentery. Perhaps upon entering the casino, you are told that you are the millionth guest, and have won the entire casino or its contents - your choice. Maybe you simply win every bet you make, and against all reason, are invited to every other casino on the strip to win there as well. **Why even stop off in Vegas?** You only have to set a goal that is possible, however improbable. Finding winning Powerball tickets in the gutter, or 100 of them isn't impossible, only improbable. Of course thinking of it in this context really blows the doors open, and drifts further away from your original question, so I'll refrain from further exploration. Needless to say, there are infinite outcomes that aren't impossible that would probably yield better results than the finite funds in a casino (a real estate tycoon uncle you didn't know you had leaves you his empire, etc.) [Answer] If it was your > > really lucky day > > > Then the casino wouldn't notice you, you would win *every* game you played, and you would win the most you possibly could win, and at the end of the day, you would probably put the casino into debt & be a billionaire trillionaire. [Answer] "Anything I do throughout this day will yield a successful outcome, no matter what the odds against it are, but only if it's possible to happen in a day." It is highly unlikely that they're going to take kindly your extreme stroke of luck, or for you to beat the odds of them catching you, or for them to let you keep playing when you're clearly just going to take their money. However, it doesn't matter how unlikely it is, so good luck in Vegas! It's also unlikely that they're going to find your winnings to be in their favor, or to be able to spin it into a net win for them, and therefore you. Again, that doesn't matter. Edit: It's also unlikely that everyone will suffer mass amnesia about the incident, your friends and family will forget about your winnings, and the casino managers will write it off as a loss and forget all about you. But fame is a very fickle thing, and it could be that by tomorrow, the only thing everyone remembers is their shameful frenzy the day before. It is unlikely that everyone will choose to forget, but that's the luck of the draw! [Answer] Well, you could make that one day a game of chance. Flip a coin, throw a dart on a map, base all your actions on pure luck. That way you will keep away from harms way and will probably not get caught. Casino could "prove" that you are cheating if you keep hitting the same game again and again, but if you win one jackpot on each of the casinos, what can they do? ``` You just need a goal, and the odds will be in your favor. ``` If the above clarification holds true, you could mentally WISH to lose some of the time, just before you move on to the next casino. "Sorry guys, it seems my luck has run out, I better stop while I am winning." When everything else fails, and you end up in the back room suspected of cheating, they might just throw you out. If the casino does not care too much about the law, after they figure out there are higher forces in play (magic, blessing, luck) they could offer to recruit you - willingly or unwillingly. Tomorrow, when your luck runs out, well, you're really out of luck. [Answer] It sounds like this luck gets triggered by your intention - until the end of the day, if you intend a lucky but plausible outcome, it happens. So, if you intend to win the maximum jackpot every round of every game you play, yes, that's very suspicious, and you'll be blacklisted after a handful of conspicuous wins. You could get a $30M single jackpot payout (at the boundary of plausible luck), but low six figures would be more likely if you play that way. However, there's nothing stopping you from looking at the whole Vegas trip as a single venture where your goal is to take as much money as you can from their games without being banned for life. If you play that way, you could probably make hundreds of millions by focusing on gambits to keep them from kicking out out right away - things like losing several hundred grand or a new Ferrari in a side bet with the casino owner might be enough to keep them scratching their heads while you clean up. [Answer] The problem with this is that it relies on a misunderstanding of "luck". The universe isn't meaningfully split into unlikely and impossible, at least not the way you think. There is some chance that atoms somewhere will spontaneously rearrange into a cosmic super-being dedicated to granting the lucky persons every wish. It's a very low chance, but some chance. So sure, there is some chance the casino don't notice. There is some chance all the people looking for cheats at that casino spontaneously transfigure into flamingos. (And a much higher chance they get stuck in traffic, sudden medical emergencies, etc.) But suppose you have a limited "luck budget". Exactly how is this luck operating? Would this luck cause an early stage cancer that you didn't know was there to die off? Nudge scientists half way around the world in the right direction to invent anti aging drugs. Or is that not happening because our protagonist is too dumb to consider it. Or is that happening as well as the betting. [Answer] Thanks for getting my grammatical errors. I'm a bit OCD, as when coding, I cannot stand errors or seeing lines with only one character or word. And, I'm pretty sure that it's not cheating if they don't know about luck manipulation being a thing (unless the casino has a penchant for being ridiculously overprepared), and thus won't have any rules against it. In that case, it's not technically cheating, so it's okay, even though it gives you an unfair advantage. Or, if it allows, even encourages cheating, nobody would care enough anyways to outlaw luck manipulation. ]

[Question] [ So, assuming that the technology is readily available and that we could build these mecha as easily as we build modern tanks or planes. What would be a good advantage in using a legged (not necessarily bipedal) combat mecha over using conventional tanks and planes? I don't need scientific reasoning (though if you have some that would be amazing), simply logistical or tactical reasoning would be enough. Some notes: 1. The mecha should use legs to maneuver rather than tracks. 2. The mecha should still have a human pilot inside the mech. 3. Soft science is good enough, but the harder the better. [Answer] The benefits and merits of using mecha are highly dependent on how big these mecha are. **Under 9' Tall** At the lowest end of the size scale, you have what is probably better coined *powered armour*. But mecha this big should be considered, if for no other reason than to illustrate where larger mecha sizes potentially don't have much use. A 90' tall isn't going to fit inside a building, but a 9' tall is... providing they smash a 9' tall door frame upon entry. I chose 9' because I pictured a person and scaled them up until they had to duck uncomfortably in my office. Then I replaced this person with a robot. This mecha is tiny by mecha standards, but is by no means a lightweight. [The average person displaces 66 litres](http://www.wolframalpha.com/input/?i=volume%20of%20a%20human) of liquid when fully submersed, and is [5'4" tall](http://www.wolframalpha.com/input/?i=average%20height%20of%20a%20person) (which strikes me as unusually small). Scaling this up to 9', my mecha displaces 332 litres. If we assume the mecha is predominantly made of Iron ([7.87 kg/L](https://encrypted.google.com/search?q=density%20of%20iron)), it weighs-in at 2.5 tonnes (sans room for the pilot). Modern militaries still use infantry for a great number of reasons, but the two I think are relevant to you are; they can go where vehicles can't, and they can make high-level decisions where-as a machine cannot (yet). Mecha this sized should be able to withstand small-arms fire much better than infantry can. If you need shock-troopers to lead an assault against a defended position, this guy is your best friend. **Over 9' Tall** For the moment, I'm going to assume that mecha weigh the same as an [M1A2 Abrams Tank](http://en.wikipedia.org/wiki/M1_Abrams) (~62 tonnes). And has a similarly sized gun, similarly rated armour, and a single pilot, and is vaguely human-shaped. The M1A2 has a crew of four(4), so a single pilot is a massive improvement with regards to minimising loss of life. Applying my scaling rules from the 9' tall case, this mecha should be in the order of ~25' tall. Taller than a two-story building, but only slightly. In urban environments, the mecha has a surprise advantage over M1A2. It can [poke-out from cover](https://www.youtube.com/watch?v=VMJuDet_dZE) faster than a tank can. It can then retreat to cover quickly too. *However* this is a pretty moot point because I don't think city buildings withstand cannon fire very well. The M1A2 simply has to aim where the mecha is hiding, and *shoot through the cover* and will either hit the target, or shower it with chunks of the (now missing) concrete wall. Since this mecha is vaguely human-shaped, it might be capable of replacing construction equipment. By construction, I mean demolition, and equipment, I mean *lets knock this wall down and block traffic. Pile those cars up in places that obscure enemy line of sight and give friendly troops a place to hide*. This doesn't need fine motor control. Just hydraulic grippers. **Where problems occur** If you want to follow *some* degree of scientific hardness, then the [square-cube relationship](http://en.wikipedia.org/wiki/Square-cube_law) is what stops you from scaling up mecha in size. If you make something twice as tall (and wide and thick) it becomes eight times heavier. But it only becomes four times stronger. Eventually, it reach a point where it weighs so much that it can't support itself (scaling down, you get proportionally stronger - which is why ants carry many times their body weight with ease). I won't say where this point lies. I that kind of maths is some heavy mechanical engineering, and it depends on what you build your mecha out of. 25' might be attainable with today's metallurgical knowledge. Then again; it might not. Speed. This is where I think tanks trump mecha. Scaling up [human running speeds](http://www.wolframalpha.com/input/?i=average%20human%20running%20speed) to 25' tall people gives silly results. Think, 200km/h sprinting. Which is more than three(3) times the M1A2's [reported] top speed. This is because I didn't factor in the square-cube relationship. I expect tanks to have a higher top speed than mecha. On an open plain, you will want tanks. That said, using tanks in an open plain *today* is probably a nigh-suicidal tactical decision. Heat-seeking missiles have speed and ranges far greater than what a tank can react to. The best defence is not presenting a target to shoot at in the first place. Land mines exist, as do people with rocket launchers and rocket-propelled grenades. Moving parts. Put simply; the more moving parts something has, the more parts that will need maintenance, and the more parts that can (and will) get damaged during use. The fewer moving parts your mecha has, the more robust it will be. Mecha that have as many [degrees-of-freedom](http://en.wikipedia.org/wiki/Degrees_of_freedom_(mechanics)) as a human are probably too fragile to be practical and will require too many man-hours of maintenance. Mecha should be treated as sledgehammers, not scalpels. **Plausible role for mecha** I think the most plausible place for mecha in a near-future military would be in situations where you need mobile firepower that's more than infantry can comfortably carry, but comes in a package that's smaller than a tank. [Answer] Barring some form of setting specific contrivance, none. The goal in building an armoured fighting vehicle like a tank is to give it the best armour for its mass, to spread the weight out over the largest area you can so it has grip and won't sink into the ground, to give it the lowest profile you can so it is a difficult target and can hide behind terrain features, and in the particular case of tanks, to pack in the biggest gun you can manage so that you can beat the armour of enemy AFVs, and to provide stability for that weapon so you can fire it accurately, even when moving. A flat, low to the ground box with enormous treads and a single big gun mounted in a rotating turret in the middle does this very well. A giant humanoid is very hard to armour, It has a large surface area for its size and complex, multi-axis joints that are near impossible to armour effectively. This is also the major difficulty with human body armour. A tank is a compact box with a turret that has two single axis rotating joints making it fairly easy to armour. The treads are more difficult, but still easier than limbs, especially at the front. Bipeds also have very high ground pressure compared to a tank. Even if given snow-shoe-like feet, a biped is going to find a much larger range of terrain to be "soft" than a similarly massive tank is. Because of its low slung design and top mounted turret, a tank is able support a gun that is a significant proportion of its own mass. A mech the size of a tank would not be able to use a gun anywhere near the size of the tank's gun. A tank is always laying prone compared to a mech and still able to move at full speed. A giant humanoid is an easy target. It can drop prone, but only if it knows in advance that it is about to be attacked, and it will take much longer to do so that a human would (it takes time to fall a greater distance) and will take more damage from doing so (Square cube law plus longer fall.) Afterwards it will be unable to move effectively until it stands back up. The agility and familiarity of movement often suggested as benefits of mecha is also going to be hampered by the square-cube scaling issues. They just wouldn't be able to move like we can, any more than an elephant could move like a cheetah. Even with a full on neural interface that makes it feel as if the vehicle is your body, the limitations and change in scale would feel extraordinarily alien. It would be something like adapting to having osteoporosis, with ordinary ground feeling soft and slippery like mud, in low gravity. With fewer degrees of freedom to worry about, it would probably be much easier to adapt existing training with other ground vehicles to tanks than body sense to mecha. Without neural interfaces or something similar, there's absolutely no benefit to a humanoid shape, and a massive increase in complexity in terms of controls. Besides overestimating the agility a giant robot would have, many people underestimate the agility of tanks. Considering they weigh 40-50 tonnes or so, modern tanks are phenomenally manoeuvrable. They are also extremely stable while maneuvering, allowing them to attack effectively while on the move, and they are extremely resistant to being flipped. Some have suggested that height gives an advantage in seeing the enemy, but there are tanklike vehicles already have telescoping periscopes that they can deployed without having to expose the rest of the vehicle. This gives the benefits of height without the drawbacks of raising the entire vehicle. A tank is also just a lot simpler to build as it has fewer things that need to be moved around. It doesn't need a complex dynamic stability system just to keep it from falling over, and it doesn't need a neural interface or motion capture system. So you can build more tanks with the same resources. So that leaves contrived reasons: We have giant humanoid chassis from some outside source that are just better than any tank we can build for whatever reason: Robots built by aliens for some inscrutable reason, or maybe giant alien carcasses. We don't have the capability to make the same materials from scratch or to re-shape them into more practical forms. Magic in some form is used to operate them and for whatever reason, magic vehicles work better if human shaped. The same goes if magic is called something else like 'psionics'. They aren't meant to be practical. Like much of the Goa'uld technology in Stargate, there are psychological/social reasons to have a design that's much less effective than could be produced otherwise. The imperial walkers in Star Wars are probably best explained as terror weapons. They are just better by authorial fiat because the author wants giant war robots. This explains them in most settings that have them including Gundam, Macross, and Battletech. [Answer] The regular options, as smithkm said, are pretty limited. I think the crux of the problem is this: Mechs are really complicated to build and incredibly specialist vehicles. But they have a form of chassis that is designed (by nature) to be incredibly generalist and adaptable. Perhaps to reconcile the two, we should try to pull them closer together. I'm going to try and describe how Mechs might work as generalist vehicles. Starting off with a question... what makes the difference between a soldier and a trech-digger? It's basically whether he's carrying his shovel or his rifle. The reason humans are still used extensively in many (almost all) fields of work, is that they can quickly adapt, use all sorts of tools, and fulfill many different roles. The only way I see Mechs working, is if they can do the same. The first is to make the designs modular. The army might have tanks, excavators, minelayers, minesweepers, transports, and a dozen other kinds of vehicles, but a Mech army has only one type of vehicle. Every Mech uses the same core chassis, which is designed for flexibility. The arms can be detached and are interchangable and there's a number of plug-in slots for additional equipment (advanced optics, radar, communication, sensors, storage boxes, batteries, whatever a mission needs) Ideally, most of this material is built not in large factories, but by small craft-robots. Ideally, it's built from components scavenged from the terrain, from other mechs, and by retrofitting existing parts. Of course, the craft-robots can build and repair each other as well. The only larger factories in a Mech army, would be the Mechs themselves (which should be quite capable of larger-scale manufactoring with the right kind of equipment) This creates a flexible and adaptable force of units. A Mech might not stand up to a Tank in combat, might not dig as fast as an excavator, might not build as much as a factory, and might not carry as much as a transport truck... but if you supply an infantry taskforce with a single Mech it can suddenly do *all* these things if they come up. "Everything" is something no regular vehicle would be able to do, but a Mech can take a pretty good shot at it. It makes some sense to equip (off-world?) exploration forces, fast landing troops, and hard-to-reach areas with a few Mechs to make them able to deal with whatever crap comes their way with a reasonable chance of success. Consider them as flexible tool-wielders rather than machines of mass destruction. Rather than vehicles, which are tools used by people, a Mech is a tool-wielder used by people, but it's what the Mech is equipped with today that determines what it can do. And of course you *will* see them in combat. After all, humans are still fighting, even though they are no match for a tank. But in an open battle, they fulfill a support role. And so would Mechs. They would shore up whatever gaps a force would have. Lost your anti-aircraft vehicles? Equip Mechs with surface-to-air missiles. Communication network down? Use Mechs as mobile radar outposts. Need to deliver ammo to an outpost on a steep hill? Attach the climbing hooks and load up a few storage boxes. Whatever the unforseen problems of war are, a Mech and a bit of engineering can at least fix the worst of it. Mechs would be the among the worst options for a lot of jobs, but they would still be a better solution for any problem than "sorry, we have no specialized vehicle for doing this". [Answer] From a comment on [What are the enabling factors for melee combat in modern or future settings?](https://worldbuilding.stackexchange.com/questions/3358/what-are-the-enabling-factors-for-melee-combat-in-modern-or-future-settings?rq=1) , consider melee or close-range combat in the context of nonlethal combat. Suppose a *very* high premium is placed on not killing opponents but instead capturing them alive - religious or other moral reasons, for example. Heavy artillery and long-range indirect fire are ruled out by this, and instead combat moves to close-range incapacitation. "Tank shell vs mech" is no longer a problem as that would be considered a war crime. Meanwhile the tank becomes very vulnerable to infantry prising the hatch open. Also, you can't take infantry prisoner with a tank in the way that you can't with a submarine. Everyone wears at a minimum NBC suits in order to avoid the obvious vulnerability to gas weapons. Grappling and nets become widespread. People add combat exoskeletons to overcome opponents with physical strength. The exoskeletons get larger and heavier. Conflict is closeup punchups until one mech is disabled and infantry apply can-openers and take the pilot to a POW camp. [Answer] I'm going to ignore the science mostly, but here are the "traditional" sci-fi reasons for mecha over tanks based on what I've read: 1. **Terrain**. Presumably a bipedal model can go more places than a tank. Whether it's climbing a cliff, fitting through narrow areas in cities, or jumping a pit, your mecha is more capable than a tank at getting around. 2. **Familiarity**. A mecha moves like a human does, so if you have the right interface that means you can take advantage of 18-20 years of moving a human body and turn that into experience moving your mecha. Tank drivers start from scratch. 3. **Agility**. A mecha can dodge, jump, duck, take cover, hit the ground to avoid a blast, etc. A tank can... tank. 4. **Flexibility**. A tank is a weapon. A mecha is a weapon, but it can also double as a construction tool to build barracks, throw up walls, etc. 5. **Ammo**. If a tank runs out of ammo it can ram things. A mecha can use a knife, punch, kick, throw rocks, throw enemies, or basically do anything an unarmed human can do. [Answer] I think the question to ask about mechs is how could they be better than tanks, but how they could be different than tanks. For reasons outlined by other posters, the role of heavily armored combatant really favors the tank over giant mech (stability, area of armor facing, ground pressure of a massive vehicle). That leads us toward a non-tank combat role for the mech. user6511 hit on the possible utility of a small, 9' size mech. I want to expand on this idea some more. Lets say we size our mech somewhere around 10-11' fully upright, less crouching or on all fours. Weighing in at around 3-4 tons. The driver sits in an armored chest, perhaps extending legs into the upper legs of the mech. The legs are a little squat, and the arms are proportionally longer than for a human. This lets it transition between bipedal and a "heads up" quadrupedal movement somewhat like a chimpanzee. Quad movement options give it redundancy in case of limb damage, to help negotiate poor terrain, and to let it lower its profile to make use of cover. It has a remote weapon station with a medium machine gun and low light/IR optics. This is slaved to a helmet the driver wears, similar to that on an Apache gunship, allowing the driver to look around and aim the machine gun with head movement. The RWS carries smoke launchers and other defensive systems allowed by the tech level of the setting. It has grasping hands, not dexterous, but strong, useful for building fortifications, moving ordnance, helping stuck vehicles, loading pallets, knocking down barriers, climbing certain types of terrain, walking on all fours, and stabilizing a heavy weapon. In addition to its head mounted machine gun, it carries a heavy weapon. A .50 caliber HMG, a 40mm automatic grenade launcher, or a 30mm autocannon (probably only a low-velocity, helicopter gunship version). This can be stowed on the back of the mech. A couple of tubes of anti-tank missiles or recoilless rifles (depending on the need and wealth of the mech's suppliers) might be available. All weapons could be detached and used by supporting infantry as needed. Armor would be centered on the driver's station. It's armored against heavy machine gun fire, with mounting points for autocannon resistant plates in the front chest and top of the shoulders (so if it's on all fours, the part facing the enemy is still armored). The limbs are armored against general purpose machine guns, artillery fragments, and maybe heavy machine gun rounds if armor technology allows it for the weight. They're not cannon-proof, but they're, hard to hit and easily replaceable. An Active Defense System gives it a chance to survive missile and RPG attacks. It doesn't get in fights with tanks without good cover and ambush positions, so it has no protection against main battle tank rounds (but what does?). What does such a vehicle offer? It gives infantry forces a source of vehicle-grade sensors, combat engineering support, and mobile heavy weapons that can travel in traditional infantry friendly environments such as urban rubble, dense forests, etc. It is a combat vehicle that can travel at roughly the height of a walking infantryman, and adapt its shape by crouching or going prone to use cover against heavy weapons, extending its weapon station optics only far enough to peek over obstacles. Combined with its fairly small size, this allows it to use cover in ways that most combat vehicles cannot. It is a combat vehicle that is easily transported along with the infantry. A couple could be loaded into shipping containers or on the bed of an HEMTT, or in a semi trailer. One could load into a MV22 Osprey with some infantry, or a couple could be carried by a Sea Stallion helicopter. A whole bunch would fit into a C130 transport. It could form the core of a rapid-reaction force that would be much stouter than an all-infantry force could be, but would still be essentially helicopter- or truck-mobile, with all the logistic and planning conveniences entailed by that. In restricted terrain it would give some armor and heavier weapons to an infantry force to help overcome another infantry force. In such terrain, it could use its flexible geometry to take cover in places vehicles otherwise couldn't, allowing it to make attacks on heavier armored vehicles from an ambush, denying access to these vehicles. That's how I see it, at least. I don't really know more than anybody else, though. [Answer] # Bipedal Mechs are not the Right Choice™ I am noticing a lot of answers focusing on bi-pedal mecha. I think this is a poor choice for many reasons and I will list them and then move to why I think they matter. 1. (lack of) Redundancy 2. Limits to locomotion 3. Complicated joints 4. Bad Height 5. Awkward Stability I agree with @user6511's post about bipedal mecha in some ways, especially for mecha under 9 feet. For small mecha, I think that bipedal *may* be viable. However, I think that it will fall short of expectations once it is bigger than what is essentially the marine armor from Starcraft. My proposed solution is a hexapod (or octopod) mecha. The additional legs would address all of the above points while maybe keeping the weight of the mech down and probably making it easier to produce. ### Lack of Redundancy If one joint is even slightly damaged the mech is going to come down. Human locomotion is extremely sophisticated and a surprisingly delicate balancing act. It could be *worse* than dead weight if it won't move properly. What is the solution? More legs! In a hexapod mecha even if one of the legs is blown completely off it will be fine, in fact, it could theoretically still remain mobile with half its legs even if it is slow. That is a lot more than can be said for the biped. ### Limits to Locomotion Because of the square-cube relationship (where things get heavier way faster than they get stronger) its unlikely that a 2 legged mecha will be able to jump or climb very well, they will be dependant on a surface that can be walked on, even if it *may* be able to be more jagged or steep than a surface a tank could traverse. It would have to have very big feet for balance and to support the vertical weight. What could fix this? More legs! Hexapods to the rescue. It has more points of contact, therefore, spreading out the weight over more space. Additionally, with all of the legs it has, it's very feasible to say that it could jump. Not as dramatically as a spider, but being able to leap a short distance in an emergency could be life-saving. I theorize that with the extra mobility options it would never have to though. It can easily traverse tall ledges, step across trenches or over roadblocks, and because of its many points of contact, it would definitely be better at handling steep slopes and jagged terrain than tanks or bipeds (although I guess not as well as planes technically). ### Complicated Joints Didn't I already talk about complex joints in point 1? Yes! But not enough! The very minimum a bipedal mech would need for each leg is 3 joints... wait, isn't that the same amount of joints as in a hexapod mecha leg? Yes, but also no. The knee joint is simple, it just needs one axis of movement, hooray! But if you want your mech to be able to balance itself the ankle needs 2 axes or the mech needs to be moving its arms around a lot to throw its weight into the balance corrections. The arms moving around a lot seems like a bad idea for many reasons even if the weapons are not attached to the arms so I am assuming that the ankle either has 2 axes of movement or its a complex multi-part foot with either [2 joints in addition to the ankle joint](https://i.pinimg.com/736x/cc/3c/41/cc3c41f9b46be57d0c5e479b890c9b6f--robot-design-character-concept.jpg) or [4 total joints within the foot and no ankle joint](https://orig00.deviantart.net/0a16/f/2013/195/b/a/mecha_front___raptor_by_shimmering_sword-d6cx6n5.jpg). And then the hip joint, even assuming simplicity, will need at least 2 axes of movement. If it doesn't then the robot can't turn its legs unless you want to throw even more complexity into the feet. So how does the hexapod fix this? Well, each leg needs exactly 3 joints, just like a simple bipod, but each of these joints only needs a single axis of movement for the robot to be able to do everything it needs to do. The joint attaching to the body only needs to be able to move in an arc parallel to the ground, and the two leg joints only need to be able to move perpendicular to the ground as you can see in my incredibly detailed and beautiful diagram here. [](https://i.stack.imgur.com/GdXz1m.png) (red arcs are arcs of movement) So while it may have more joints total, the simplicity of them allows a lot more options for what can actually be used to control them and how they are manufactured and serviced. ### Bad Height Bipedal mechs kind of have to be taller because of the nature of how they work. The stubbier their legs are the harder it is for them to balance and move and the less benefit you actually gain from having them in the first place. They are easy targets because of their height, and being an easy target just makes it that much more likely they are going to get shot. Being shot is bad, so being tall is bad. Hexapods are able to easily stay close to the ground, in fact, they can position themselves so they are only barely taller than the cabin (cockpit) that the legs are attached to and still locomote. They are also able to make themselves taller than their standard resting position if necessary to poke their weapons above a piece of cover or terrain. ### Awkward Stability Now bipedal mechs would have some sort of shock absorber on them for their weapons firing I am sure, so we can assume their own weaponry wouldn't pose balance issues for them, but what about taking heavy fire? Only having two points of contact (and relatively small ones for their mass) is not great when you are taking that much force straight to the armor plating. There will have to be constant balance calculations and adjustments made even for just normal operation out of combat and their stability just gets even more calculation intensive and delicate once they are in rough terrain and required to move quickly while possibly under fire. I am not a physicist but it seems to me that if its armor cant take the hits its dead, and if it can take the hits it might just fall over because of its high center of gravity. A hexapod does not suffer from stability concerns. Even with several legs missing it is simple to move. Additionally, because of its low center of gravity and proximity to the ground it almost cant "fall over" even if it does get hit hard enough that its many legs cant stabilize it. # Hexapods are Boss The hexapod mech has many advantages to biped mechs. It is able to maneuver through extremely complex terrain, climb very steep surfaces, stay low to the ground, can fit through almost any space that is at least as wide as the cockpit ([leg configuration for fitting through narrow spaces](https://i.stack.imgur.com/F3XRd.png)), theoretically be straight up faster, and because of their simple joints should be easier to manufacture and maintain. They would be advantageous over tanks for their mobility in weird terrain (because of their ability to increase their height they would be better at fording rivers. Tanks usually have [Deep Wading](https://en.wikipedia.org/wiki/Deep_wading) but it takes setup time, endangers the crew, and any leak in the tank is bad news. Why not just walk above it?), ability to simply step over/onto/into roadblocks and trenches, and with the right attachments have *any* of the more advantageous aspects of a biped that other answers have suggested. [Answer] In both Neon Genesis Evangelion and Full Metal Panic the use of mecha is explained by the fact that the mecha they can build are much more advanced than what they can build in other form factors. Basically, if people of the setting have some technology usable for mecha that is far more advanced than their normal level of technology, mecha will be superior to other forms of military technology. **Magic**, there might be some mystical reason that requires human shaped mecha. For example the mecha might actually be transformed humans. Or the control system might rely on the mystical resonance between the body of the mecha and the body of the pilot. **External source**, the technology is derived from an external source, possibly aliens, that has its own agenda and provides technology in isolated snippets. Aliens would do this on purpose to make reverse engineering more difficult. Other possibility would be technology retained from the lost dark age of technology in incomplete form. **Isolated breakthrough**. People might have invented a very efficient and cool technology that they still can't apply in other ways. This happens sometimes, but usually the period is brief. Possible cases for the mecha are the control system and pseudo muscles used. First generation neural link might only work properly if the controlled body is similar enough. Somebody might invent pseudo-muscles that have ridiculously high performance and/or efficiency. I doubt this would last long enough for mecha to get very common or advanced. More realistically, mecha are really between infantry fighting vehicles/light tanks and helicopters. They are not really designed to be tough and exchange direct fire with MBTs, although they would probably carry anti-tank missiles, they are meant to give higher mobility than most ground vehicles with less noise and expense than helicopters. This points to some requirements that would help with mecha adoption. The obvious one is need for rapid response units. Mecha would be lighter to airlift than an MBT, could hold their own against light vehicles, would add heavier than man-portable weapons to infantry groups and require less logistics than aircraft. The legs would probably be designed to act as shock absorbers for jumps, so the mecha should be able to do air drops. Similarly even in urban environments mecha would only have significant advantage if they can jump repeatedly significant heights or distances. Due to obvious reasons of geometry this would put an upper limit on the mass of the mecha. And require at least the legs to be fairly efficient and powerful. A very long legged vehicle, functionally similar to a helicopter that can hover noiselessly and without using fuel, but only at a low height, might also work. Lack of noise might be important. Modern tracked vehicles can be fairly silent, but a legged vehicle could **really** sneak on someone. And if the terrain has some obstructions a mecha would have a better chance of navigating them silently and without collateral damage than a conventional vehicle. This might make mecha practical for suprise attacks and peacetime operations in urban areas. [Answer] Advantages in a large leg-driven vehicle would be the same advantages that are leading people to [pursue legged robots](http://en.wikipedia.org/wiki/BigDog): maneuverability in rough terrain. Dense forests, rocky hillsides, and urban cityscapes can all have barriers that prevent conventional vehicles from driving through them. Steep hills, as well, can be impassible for a wheeled vehicle. A legged vehicle or robot, however, can step around or jump over obstacles, and regain its balance if it loses its footing. Human-shaped vehicles that are also *human sized* have the additional advantage of being able to maneuver through environments that were built to be inhabited by humans. Stairs, for example, are useless to vehicles, but a person in a powered suit of armor would be able to use them without a problem. For vehicles smaller than cars, being human-shaped also provides the best protection for the human encased within. Compared to something like a motorcycle or an ATV, something like powered armor will offer greatly increased resistance to hostile firepower for the pilot inside. [Answer] The primary tactical use for using combat mecha would be heavy urban combat in areas where it is difficult to fit a tank or other armoured vehicle. Mecha have the advantage that they would be more manoeuvrable over irregular terrain and in tight spaces, and would provide their pilot a significant force multiplier in these situations. However, Mecha, especially of the humanoid variety, would have disadvantages in open-terrain combat in excess of that of wheeled or tracked vehicles, in that they have a greater surface-area to volume ratio as a consequence of their design, requiring more armour to be carried to protect a given volume of vehicle, thus making mecha less useful for carrying weaponry. Another disadvantage of humanoid mecha is that for a given volume, they would stand taller than an equivalent-volume conventional vehicle, providing a more exposed silhouette to the enemy. Finally, mecha would have the additional disadvantage of a higher production cost and more complexity in maintenance due to the necessity for controlling limbs. As to why mecha may have been fielded in the first place, one scenario I posited for an RPG game world was that mecha originated on a continent where cavalry animals became plague-bearers, and where (for various reasons) effective chemically-propelled projectile weapons had not been developed. As knights were unhorsed, they were forced to turn to infantry combat, which led to (literally) mechanised infantry which would use giant versions of infantry melee and muscle-powered missile weaponry. [Answer] It depends on what you mean by "mecha". If you essentially mean a powered suit, then making infantrymen into superheros is a good reason. Getting beyond that you start having to reach for reasons, and the practical answer there is life support (the mech carries the pilot's environment with it). Incidentally, Heinlein explored both aspects of this to some degree in Starship Troopers (read it if you haven't). I'm not sure how far in the future you are trying to tackle, or on this world or in/among others, but for terrestrial combat large mechs are just not very practical, so you need another reason -- but that reason could simply be organizational interia. For example, in the tricky and various terrain that exists on and among other planets and planetoids there pretty much isn't any such thing as a non-mech equipped infantryman, and it appears to be simply impossible to delegate all ground-level decision making to AIs (a fact we've continuously been confounded by in the real world). The great flexibility of delegation afforded a military force that can send actual humans to a site of battle (even if primary combat is robotic) will very likely make a mech-style infantry force a reasonable compromise in the real space age of the future. If this were true, it is also likely military industries will be tooled to build large numbers of mechs, but perhaps not many tracked or wheeled platforms simply because the utility of such vehicles is drastically limited in most space settings. If the above assumptions were to hold, then a driving force behind the use of mechs in a terrestrial setting could simply be that mechs are the primary mode of available infantry. It would be an organizational compromise between general utility and cost effective fielding of units. A strong parallel to that is the ridiculous vulnerability of MRAPs and armored HMMVs in real war (as opposed to a set of LAPD-style occupation focused mission statements). Unfortunately, though, the broader decision to double-down on Iraq-focused investments in the mid-aughts made this form of HMMV pretty much the only broadly available option for much of the US military, and quite a few aspects of force-on-force combat thinking had to change to accommodate this availability-driven fact. For example, an armored HMMV is so heavy that its original selling points (rough terrain negotiation; soft/hard ground compensation; negotiation of extreme slopes due to a very low relative center of gravity; general agility; utility in airborne (parachute), air assault (helicopter), and air-mobile (injecting forces from planes landed in an area held by the previous two) in soft or rugged terrain; etc.) were completely obliterated, and drastically change what maneuver options are available to a cavalry scout unit or infantrymen tasked with the traditional "11H" mission (I don't have a link for that, but basically 11H was motorized infantry; cav scouts serve a different role but in roughly the same configuration). In terms of solving the practicality/political reality dilemma you would face in building a world where mechs are commonplace, this is the only reason I can see that is plausible from every angle. Some of the reasons for general terrestrial implausibility are covered in user6511's answer (read it carefully, and also remember that the targeting style of most large weapons is basically "point and click" so the insanely bad visibility of an upright machine is a bad thing). A big part of the decision making is how plausible is "plausible enough" for you? The idea we are going to build a mech that weighs dozens of tons and can ninja flip, John Wayne slap, or otherwise go Chuck Norris in combat is a bit dense. Consider how much torque and oblique pressure would be applied per square inch on a single foot were a 50-ton mech to kick while standing on, say, anything other than a carrier deck or solid granite. Anything with soil would be a no-go for an even slightly agile mech. [Answer] I think some kind of mech is more likely in the near future than we might think. Two major advances will radically alter ground warfare in the near future. For the last century, offense or destructive weapons have been more powerful than defense weapons. That is about to change. ## Body armor is already beginning to reverse the trend to lighter rifle rounds. Since WWII the trend was smaller bullets, at higher velocities if possible, but always with the idea that a smaller bullet against human flesh was just as good as big round, especially if you put several close together. But in the last 20 years, body armor has begun to reliably stop the most common round sizes, usually the 7.xmm rounds of common assault rifles. The US has brought back the venerable M14 (7.62×51mm) and even .50cal (12mm) Beowolf to augment the M4 (5.56×45mm) An exo-skeletopn that let a soldier carry a hundred pounds of extra body armor would be immune to most light arms fire. This would set off an arms race between heavier but slower firing rifles trying to punch through ever increasing mechanized body armor. Computer assisted aiming will also require body armor. Todays weapons are largely about "spray and pray" compared to automated targeting, because a human cannot spot a target, or part of a target, aim and fire before the target moves. Modern crewed, medium and "assault rifles" rely on the ability to put enough rounds into the air in a small unit of time that some will hit a target. Humans are just not fast enough to take aimed shots at other humans who can move just as fast to avoid exposing themselves to the shot. But a computerized system move faster than humans. They see in "bullet time" in microseconds and human scale motion appears either nonexistant or takes the equivalent of hours. There is a bullet stopping system used in VIP protection that detects incoming bullets by radar and fires a Kevlar air bag to popup and catch the bullet. That's how fast these systems work. A human aimed gun would fire thousands of rounds across a field to try to hit some of the 50 opponents peaking out a trench 300m away. A computerized system would be able to carefully draw a bead on each individual fire one round into eye of each target. It would be the equivalent of firing rate of rotary mini-gun that targets like a sniper with all the time in the world. With that kind of system your going to hit, so you have to absorb it with armor. The historical analogy here would overhead airburst in WWI, leading to the return of the armored helment. The burst laid down such a pattern that almost everyone underneath got clipped. The only solution was to armor the head. This time will have to continue armoring everything, especially the face. ## DEW (Directed Energy Weapons): These are getting scary good to the point they can incept artillery shells and either destroy them or knock them off course. Very soon, military units will move under a line of sight dome of an intercept grid through which no projectile above a certain size,not moving at hypersonic speed, will survive. Now, if you have a powerful DEW system, then crouching out of sight may not be as useful having elevated perspective to see incoming threats so the DEW can eliminate them. Besides, given modern battlefield sensing systems, hiding is becoming increasingly problematic. Instead, you'd want a tower, or tall vehicle to put your sensors and DEW projectors up high to give them most perspective and range. Naturally, DEWs will become anti-personel weapons despite treaties. A thing that can hit a missile can hit a mobile human hundreds of times before they even begin to fall. Worse, they can hit individual parts of targets precisely as in eye,eye, trigger finger, weld the rifle receiver shut, then set of a grenade on the belt. So, again, armor is the only solution. Now, the nature of armor itself might change. It has to face two threats, kinetic weapons and DEWs. Kinetic weapons that move so fast they can penetrate the DEW grid are likely so high energy they can't really stopped, so they may not try. Such projectiles might have to be slender and solid so the best strategy might be to just let them punch though. DEW weapons don't penetrate, stop them on the surface, absorb or deflect the plasma shock, and your good. Anti-DEW armor is not heavy or dense but focuses no deflecting energy and reflecting plasma from vaporized materials when the DEW hits. Such armors to date are more thick and fluffy than dense and heavy. Sometime a mist of water or certain liquid plastic prove very effective. So, a tall, tank-analog DEW shielded mech might not be that heavy at all. I could see a new future in which tall DEW projectors will be escorted by mech suited infantry wielding slow firing hyper velocity rifles and/or anti-personel lasers. The DEW stops airpower, arching artillery, slower missiles and RPG. The infantry will protect the DEW unit from someone running out a hiding spot and beat it to pieces with a crowbar. Battles will beginning with low intensity DEW attacks in the thousands targeted at enemy sensor systems which will be constant, followed by precision attacks on vulnerable areas like joints or the unfortunate unarmored. The hypervelocity kinetic weapons will be shot at armored targets hoping their velocity will prevent the DEW grid from intercepting. (Note that with hypervelocity weapons, hiding behind obstructions or even laying below the line of the ground won't provide much protection, as such weapons can punch through any building and dozens of meters of earth.) This will not be any place for civilians. The sensor suppression will be blinding. Automatic DEW grids will likely target anything that moves. Even if not, mere reflected energy either from DEWs or shattered material from hypervelocity rounds will threaten all unarmored individuals. Primary Defenses will BE 1. Blind enemy senses and sensors with DEW, Jammers, decoys etc 2. Damage or slow with precision DEW attacks against surface components 3. Fire hyper velocity dumb projectiles at targets progressively shredding like cannon balls through age of sail wooden ships 4. Try to intercept of deflect incoming enemy hyper-velocity projectiles. On factor that will bring large vehicles, mech or not, is that the more powerful energy sources you can lug along the better your DEW defense and offense. It will become a race something like that in battleships from 1899-1936 where the biggest guns and armor won. [Answer] I think the question is not whether Mechas would be better than Tanks or not.Is infantry better than tanks? It depends on the situation. So I think if we can build Mechas armies would use them for warfare too. Scientists have researched artificial muscles for a long time and I think if they become successful Mechas could be build. Many of you have given square cube relationship as a point against Mechas.According to [this new artificial](http://singularityhub.com/2014/03/10/superstrong-artificial-muscles-developed-from-fishing-line-and-sewing-thread/) muscles they are at least twice as efficient as human muscles. And I think this would at least negate that point. If we could build mechas I think they would be excellent against infantry units. Mechas don't have to be very large. Even if they are 9ft tall I think a group of them would fare well against infantry. [Answer] In the Warhammer 40k the Space Marines have Dreadnoughts to preserve combat experience. Basically only the most honoured of the Space Marines who are mortal wounded are salvaged from the battlefield (the rest have their gene seed extracted) and put into a coffin attached to a Dreadnought. These are quite like a tank being quite wide, short, and can carry very heavy weapon loadouts. Another advantage they have over the Space Marines tanks is close combat abilities so that jump jet equipped infantry can't as easily get the drop on them. [more info on Dreadnoughts](http://wh40k.lexicanum.com/wiki/Space_Marine_Dreadnought) [Answer] Instead of gigantic mech you can use [powered exoskeleton](http://en.wikipedia.org/wiki/Powered_exoskeleton) which allows a soldier to carry more supplies (and armor), but require no control interface. These would be used in terrain too rugged for a tank. And you cab supply deployed units by caravans of [pack mules like Big Dog](http://en.wikipedia.org/wiki/BigDog) who know "follow the leader". In less rugged terrain, tank will still rule, because they can pack more power into same cross-section. One of the advantages of tanks not mentioned so far is defense against [armor piercing ammo](http://en.wikipedia.org/wiki/Armor-piercing_shot_and_shell). One of the defenses is to have armor in shallow angle (deflecting the damage), which is **much** simpler in tank than in mostly horizontal mech. Also, some [infantry fighting vehicles](http://en.wikipedia.org/wiki/BMP-2) are [amphibious](https://www.youtube.com/watch?v=umKAehJLXVM) with very little preparation - try that in a mech. [Answer] We think of tanks as superior because most of our battlefields in recent memory favor tanks. Iraq, WW I & II, and part of the Korean War all favored tanks. But the fact is, tanks are useless on a huge amount of the earth's surface, because they can basically only travel over roads and cleared terrain (deserts, plains, etc.). In fact, tanks were quite useless in Vietnam. Since most of the land that people who own tanks want to possess also favors tanks, this matchup makes sense. But Vietnam showed us the limits, and almost all fighting was done by infantry and artillery, as well as bombing. So even though mecha-favorable terrain is easy to contrive on other planets/asteroids/ships/etc., there is still plenty of mecha-favored terrain right here at home. Consider also why nature has not created wheeled creatures: although there might be plausible limits to biology which discourage or prevent the evolution of such animals, we can at least consider the benefit of legged locomotion. Legs have one extremely obvious benefit over wheels: when a leg is injured, most creatures can still move. When a wheel is damaged, most wheeled vehicles are in trouble. In general, the only wheeled vehicles which can continue moving over meaningful distances after wheel damage are explicitly designed for robustness (e.g., the Stryker[1]). If a tank loses just one link of one tread, it is pretty much out of commission until the tread is repaired. This is a pretty dangerous position to be in on the battlefield, and it is usually safer to abandon such a tank than to sit in it while it is used as target practice. We already have small [6-legged] robots which can learn to walk after losing a leg[2]. Even a bipedal mecha may be able to limp along or fashion a crutch if one of its legs becomes damaged. In a worst case, it can probably crawl, which may still be better than just sitting there spinning on a single track. Modern technology is quite often optimal-but-brittle. When it works, it works great. When it breaks, it often becomes quite useless. Biology, on the other hand, tends to be good-but-resilient. It usually trades optimal solutions for robust ones, because surviving is more important than that last 10-20% of performance envelope. Especially if I were trapped on another planet, I would much rather be in a mecha than a tank. If I got stuck in a bad situation and had to run, it may be easy to get trapped via terrain in a tank, and much easier to escape and evade in a mecha, especially if my enemy knows my capabilities. Then you have damage resilience w.r.t. locomotion, and finally you have melee combat. Humans are not dangerous creatures because we have giant claws (we have puny, pathetic claws) or sharp teeth (we have tiny, brittle teeth) or massive limbs for pummelling (we have fragile hands and feet). Humans are dangerous because they can turn almost anything into a weapon. And that is why humans are at the top of the food chain rather than the middle. So while a tank can indeed ram things, using its momentum and mass as a blunt force weapon, it has no ranged attack other than its main gun and maybe a coaxial machine gun, which have finite ammo stores. A mecha can fight as long as it has energy, even if it has to use boulders and debris as weapons (but as the Japanese have taught us...always carry a sword!). Of course, a mecha may be able to climb walls/terrain, whereas tanks generally can't do this. And even just jump jets would allow a mecha to clear obstacles which are totally insurmountable for tanks. The simplest way to stop a tank is called the Czech hedgehog[3]. This is nothing more than a few pieces of iron welded together. It doesn't even move! But it pretty much impedes the motion of even the most advanced tanks. Or, you have the even simpler solution of coils of concertina wire[4]. None of these devices would presumably stop a mecha. In fact, trying to devise fixed defenses vs. mecha would almost certainly consume the efforts of a modern war college. Passive defenses would basically be useless. Even a high wall could be defeated by grappling/climbing capability, not to mention jump jets. Only active defenses would be effective (turrets, missiles, directed-energy, etc.). Mines, trenches, and hills at least force a tank into a particular path (e.g., focused-fire deathtrap), but could be easily evaded by a mecha with jumping capability. Then consider armor. While a tank can presumably carry more armor than a mecha, a tank's armor is integral and is not easily or quickly replaced when it is damaged or consumed (in the case of active armor). And the armor is fixed, and thus must apply to all sides of a tank which might be vulnerable (front, sides and top). This makes a tank much heavier than optimal. A mecha can carry extra armor as well, but limit the armor to just the expected line of fire. Just like a low-tech sword has "infinite ammo", a shield can be just as effective for a mecha as for a tank, but can be trivially replaced in battle. And since the mecha doesn't need to carry the armor on non-threat sides/flanks, it can afford to carry much less of it than a tank (though at the loss of protection from flanking attacks, of course). Since tanks are cheaper than mecha, the mecha could be deployed like Spec Ops: soften up/disable the defenses so that the cheaper and more numerous tanks can sweep in and pummel the enemy. But the richest actors would just field all-mecha armies, because the mecha are more flexible, whether human piloted or remote or AI. They consume less energy than aircraft, because they don't need to fly most of the time, and thus, they can carry heavier weapons. If you need to cover large distances quickly, you can have transports just like you do for infantry: both ground- and air-based. You may even be able to deploy mecha via low-orbit rocket, drop-ship style. It's not safe or efficient to deploy infantry this way, but it might make sense for mecha. Finally, consider that mecha may serve a role much like nuclear weapons do today: the threat they pose changes the way nations behave, whether the weapon is actually used on the battlefield. Nations may simply forgo tank defenses and focus on defenses which are also effective against mecha. This might actually work in favor of tanks. If nobody builds mecha, then this approach is not necessary, and nations just bulk up for conventional warfare. If some nations have mecha, then any nation which fears them will have to defend against them, at considerably higher cost than non-mecha armies. Thus, everyone will want to build enough mecha to pose a threat, even if it is not enough to lead a full-scale invasion on their own. 1. <http://www.wikiwand.com/en/Stryker> 2. <http://www.engadget.com/2015/05/28/robot-crawls-with-legs-damaged-aww/> 3. <http://www.wikiwand.com/en/Czech_hedgehog> 4. <http://www.quora.com/What-are-some-effective-tank-traps-in-a-modern-warfare-environment> [Answer] To answer the question of "Why would we make a robot that looks like a person?" we should first ask "Why do people look the way they do?" That is, what problems did the human form evolve to solve? We know that the development of intelligence guided our species' evolution. As our ancestors became smarter, the ability to make good use of intelligence became increasingly valuable. To prehistoric hominids, that meant tool use, which required appendages that could effectively manipulate the environment in a wide variety of ways. So the most obvious reason for having mechs is that you need machines that can effectively use a wide variety of tools that are similar to those that humans would use, but on a much larger scale, or with more durability or strength. This need for adaptability is going to underlie most of the reasons presented here. To give a plausible near-future scenario, let's say for instance that we want to send a construction team to Mars to build a colony for the first civilian inhabitants. An individual mech might be larger than an individual construction vehicle, but it can do the jobs of many different vehicles. Weight is an extremely important factor when it comes to space missions, and a team of mechs would add up to weighing far less than an entire fleet of construction vehicles. The example of Mars also brings us to another possible reason: you're fighting on a planet that has very different gravity than Earth. With human soldiers, you'd need to train them how to move and fight in many different gravitational environments, which could be very difficult: you could be on an Earth-like planet for one mission, a rocky "super-Earth" for another, and then after that you could be on a dwarf planet like Pluto or Ceres. With mechs or robotic soldiers, instead of having to retrain your soldiers, you can just recalibrate them for the new gravity. Another reason could be preservation of combat experience, like with Dreadnoughts in Warhammer 40,000. Perhaps military training or willing soldiers have become extremely rare, but an injury in battle has put them beyond saving by conventional medical means, to the extent where they can only be kept alive by extensive prosthesis or life-support. A Dreadnought needs to be as large as it is because it has to contain an entire suite of life-support systems. Now, regardless of which explanation you choose to use, you are going to need to also explain two things: first, why not just use an artificial intelligence, and second, why is an on-site rather than remote-control pilot necessary? Answering the first question isn't too difficult. There are sound ethical arguments that have already been made in the real world arguing that general AI should be avoided. For instance, there's the classic objection that creating a human-like AI to perform a specific task of your choosing amounts to slavery. Perhaps the risk of tech-savvy hostiles hacking your AI is too great. Or perhaps you'd go for something more like in Warhammer 40,000: AIs, lacking a "soul" or some other essential and intangible element of humanity, are not able to feel the Emperor's presence and therefore are much more vulnerable to corruption by Chaos. Or maybe they just haven't been invented yet. As for the necessity of the pilot being on-site, this can also be explained very easily. An enemy could, with only very simple tools, easily hijack or simply jam the remote control signal. In the real world, this has already been done with UAV drones, and the US military invests considerable time and effort into keeping their UAVs safe from being taken over by hackers. So while we might not be seeing Gears or Gundams or Titans anytime soon, it's by no means the most outlandish thing to ever appear in science fiction. [Answer] More then likely the evolution of legged vehicles in combat will not go directly to mechs. More then likely you will start with a kind of power armor ranging from 8 to 10 feet tall. Their systems would not be fielded until they were at least as maneuverable as a humans. The major advantage of them would be increasing speed, strength and hopefully survivability of the pilot. The increase in strength is what would make tanks extinct. Right now a man portable AT missile is very heavy and bulky and the average man can carry *1*. Now imagine a suit of power armor that is at least as fast as a man but more then likely more so with anywhere between three and six AT missiles on its back you now have advanced infantry that can kill six tanks for every one man and realitively hard to hit with weapons that will cause significant damage in one shot. As these suits are refined and perfected, wheeled and tracked fighting vehicles will become more and more rare because the power armor is so effective. You will likely see normal vehicles relegated to supply and transport duties. So then what happens when everyone has power armor you start trying to outdo the next guy eventually that will lead to suits being specialized with assault suits growing in size to hold more armor counter measures and weapons until eventually they may be the 3 story tall monsters we see in fiction and the other direction stealth or recon suits getting smaller lighter maybe even capable of flight to the point they are almost a second skin. So it would take years for tanks to leave the battlefield but when they do which will probably be because the anti tank systems are so deadly in smaller more maneuverable power armors they won't come back because people will see wheeled and tracked vehicles to be old fashioned ideas and will prefer to build and expand on at that point existing power armor mech technology. [Answer] Roles of the Abrams. Tanks have a significant role in war, if we could build a Mech it would be a boost in fire power and technology plus it could give the US an edge in warfare, (Not saying other countries will do the same) with the abrams and its 120 mm gun, it is a powerfull weapon of pure destruction. Although it suffers in close range combat. you have to rely on the armour to save the crew. the speed of the abrams is quite admirable compared to its weight. The abrams it -self is a heavy tank used mainly by the US military. It is an amazing piece of machinery. its made for pushing the line and killing all of the opposition but at the same time with a surviving factor. Mech's Role in warfare: A mech could be an astounding feat in military tech, we are able to create mech's its just that our military doesn't want to spend time or the money to make a new weapon that may or may not be practical. Requirements Speed: 45-75 km/h weaponry: any and all that will be able to be installed depending on the variation of mech (infantry, Support, Anti-air and long range support) Height: 15 - 25 meters Tall Material; lightweight yet strong. Suggestion: Titanium/cobalt alloy or aluminum/titanium alloy. you need a strong engine for the beast as well. Diesel and Gasoline would make the Mech loud. Go with the turbine-like engine but it is modified to take the weight of the mech. crew: 1 Piolet 5 Pit crew: 2 Mechanics, 1 Electrical and Programing Chief, 2 reloader's There would have to be constant repairs. Tracks vs. Legs . Tracks: good traction, great with rough terrain. higher speeds achieved on rough terrain (excluding small rocky terrain) High Durability. Tracks Cons: low traction on ice or other terrains that is flat and slippery. Break when explosives are applied with great force and cannot be repaired quickly on fields. and can be disabled permanently and only made for salvage if damaged enough. Loud when stopping Legs Pros: Great on hilly terrain and best for urban combat. Open fields will give you your max speed. Better at traversing obstacle terrain by stepping over or around objects such as road blocks. Better manoeuvrability with swaying and left to right movements. Faster acceleration. Can be modified and Repaired with less time depending on the complexity of the leg itself. More responsive. less sound unless running. Optional for modification for various terrains from ICE to SAND (X-shaped feet with spiked pins for ice and flat wide feet with v-shaped trends for sand) Better stability and can stop faster making less noise. Legs Cons: Constant repairs and evaluation. Can not hold as much weight depending on what type of system it is using ( Pressure, Servo or Gyro). Damage to the leg can be fatal, just like a track, if damaged enough can be disabled, legs have an advantage in this however in the silhouette of the legs beeing long and thin or short and large( medium size or 35% - 45% of the mechs height is in the legs for longer strides. more Parts, A small servo or Gyro could be hit making it off balance. Weaponry: Abrams: 1x 120 mm cannon HEAT and APDS 2X 50. cal Guns Mech: any size cannon below 180 mm Missiles. Machine guns. high Calibre rifle (like a 35 or 75 mm High-Velocity cannon for taking out APC's and Smaller Vehicles) Any type of ammo for the cannon. Mech styles and loadout: Infantry: 2 Missle Pods and 2 high calibre Machine guns (20 mm) Body type: 2 legs, tall and slender for good manoeuvrability Amor: High speed: 55-84.6 km/h Sniper: high Calibre rifle (57 - 120 mm Cannon) Body type: 2 legs, short and thin for good concealability Armour: medium speed: 45-75 km/h Support (artillery): 155-180 mm field Artillery Body Type: 4 Legs/ Spider like ( recoil Compensation) Large Bulky but Armour: thin armoured speed: 15-25 km/h Scout/Recon: small calibre semi-automatic cannon (30-57 mm cannon) for taking out small vehicles and encampments of soldiers. Machinegun's if possible. Jamming capabilities 1 missile pod (4 to 12 missiles) Body type: Short and slender and light-weight Armour: Light Speed: 65-100 km/h Mech/Tank Destroyer: Large calibre High-velocity cannon (120-155 mm cannon) ATGM's and EMP/jamming capabilities. Body type: Short and bulky Armour: HEAVY (to deal with multiple impacts without penetrating Speed: 20-45 km/h Anti-air mech: High fire rate (25-35 mm flak) Body type: medium armour for protection from bombs and strafes Speed: Medium of 45- 65 km/h Tanks have been the dominator of the battle for a long time since WW1.If we had made the time and money to research into mech's we could make a super weapon and get ahead of most other countries. Mechs can have the ability to climb, crouch and other physical Abilities Tanks cannot. They may or may not be practical in a situation but I am sure as hell they could get the job done. Overall it definitely would be a good idea to spend time into making these machines, we could also use them for construction, medical, firefighting, exploring out deep ocean, ETC . There are endless possibilities for design and purpose. It would cost money but It would be worth getting rid of old tech that is obsolete. The mechs dont have to be huminoiid in shape you can make a sleek or bulky one depending on the job!. Though replacing all of the old stuff would create imbalance for the economy in the US, WE would have to make specialised Factories to make the mechs in the first place. also What do we do with all the abrams tanks you ask? use half or 25% of them to be used in a shooting range to test new weaponry of course! again. I could take a lot of time to get the mech project going but it would be a super great idea Other Info: Mechs need a good armour value to be able to deflect and take shots, though tanks can get better angles a mech still has the ability to make a fear factor and it has better maneuverability (not saying it will dodge bullets). AP rounds can be blocked with composite armour and that's why I suggested, Titanium/Cobalt or Titanium Aluminum. Though we could also use HEAT Shell screen's (look up on WW2 tanks) These would block RPG's and HEAT rounds from tanks. we could also add ACTIVE protection systems to protects against ATGM and Indirect fire weapons such as mortars. the tank will still have an advantage in angle but not manuverability or vewrsatility of a mech because Of the high modification abilities. [Answer] Versus a tank, in conventional tank-warfare situations, a mecha is likely to lose, for all the reasons above. So – where might it be useful? Let's look where we don't have tanks warfare: * much of the work done by allied forces in Afghanistan etc. was done without tanks, but smaller vehicles. Why? I think manoeuvrability in a city which you're trying not to destroy with big tanks. A mecha here is good. Top speed isn't an issue, but fairly quick direction changes, fitting into more awkward spaces, etc. could be more valuable. * psychological warfare. Often, tanks are used as a big threatening thing against small people / vehicles. (Think many coups, patrolling an occupied city, ...). A mecha could have an even stronger psychological value, due to the increased height, and the familiar humanoid silhouette. * fighting smaller things than tanks. Tanks can't bring their big weapons to bear very close, due to the way they're designed (the turret's elevation). Whilst obviously countermeasures exist, they're relatively vulnerable to humans with satchel bombs, etc. A mecha can be designed to bring all its weapons to bear at any range, any angle. It can kick humans. So against a mix of smaller troops / vehicles, it could be at an advantage compared to a tank. * extremely difficult terrain. A multipedal tank in particular should be able to traverse much more difficult terrain than a tracked tank. (e.g. GITS's think-tanks). It could potentially climb buildings and similar. This could allow heavy armour to reach all kinds of places you can't normally get it to (mountainous regions, etc.) [Answer] The only real reason for mecha is for show. It's big, powerful and shows the enemy how technologically advanced you are. It's just like aircraft carriers. They are more show than anything else in a real war. Tank are really more for show when a modern soldier can carry weapons capable of destroying them. The key to future warfare is cost and numbers. Why build a giant robot as big as a building when you could build a million explosive drones for the same money? See [Slaughterbots](https://www.youtube.com/watch?v=HipTO_7mUOw) The only possible real use for a mecha I can see is perhaps as a mobile drone command centre. It could also back the drones with artillery fire against hardened sites. [Answer] The closes thing to a ideal mecha today, is a battle helicopter with optional legs. So if the sneaking around mountain-tops does no longer work out. It can "run/climb" into denied areas, take a shot and then retreat. Walking should be a measure of last resort. So how would it look? Like a shitty compromise always look- not very sleek but functional. Three, thin- discard-able legs, that are able to push the weight. The armor is the terrain. Quite literally. Plastic bags with dirt are used as temporary, discard able ground Armour once landed. All things needed for airworthiness are hidden away for protection. The Main weapon should be at the highest point- so moveable from the lowest point. The periscope-pole with the sensors of course remains. The main problem here, is- its weight- makes more terrain soft for it. Meaning it will need good sensors to find stable terrain pre-leg touchdown. [Answer] There's some good answers here, and pretty fundamentally - if you use 'real world' mechs just don't work. So I'll offer instead an excuse why you might use one, despite tanks being generally better. With reference to Dune - in the setting, a lot of combat is hand to hand, because personal shields exist. Personal shields deflect projectiles moving at any significant velocity, and make the user largely immune to guns and explosions as a result. So they resort to close combat, because of the relatively lower velocity, but higher force-per-unit-area of swords/knives etc. \* I daresay you could apply a similar fudge in your world. Invent the ubiquitous shield generator, making people move away from ranged combat to melee, and suddenly your mech-with-sword type combat unit becomes more viable. For bonus points, have the optimal velocity/force to penetrate a shield related to size, which means there's a useful strategic advantage to bigger mechs. You do still have the pretty fundamental square-cube law problems as other answer-ers outline though. So you'd need something pretty compelling to over-ride that. \* Other weapons do show up - there's artillery when shields aren't used because of sandworms, and lasguns which aren't used *normally* because they explode when they shoot a shield. But both are only effective in an environment where shielding is artificially inhibited by environmental factors. [Answer] Bipedal mecha are not better than tanks, in any size (see square/cube and also see balance). Best will be quadra-, hexa-, or higher -pedal robots that can deploy in semi-autonomous swarms. A single 50-ton "super-unit" will never beat 50,000 1kg units, especially when those 50,000 units are coordinating across dozens of meshes. [Answer] I only read the first view answers so I'm not sure if anyone mentioned this in later replies but the square vs cubed scaling problem mentioned in the first couple of replies assumes the Mech would be solid, or mostly solid, throughout like an animal body. But would they be solid? Most machines aren't. Assuming you can build your Mech very big (if the metal can withstand the stresses - ask an engineer because I don't know) it's overall density could be low, very low. That's why ships float and planes fly - their density is low because they are mostly empty space. Following is a simple calculation for a 30 meter sphere made of steel at a density of 7.85 kg/litre: Volume = 113,097,335.5 litres Weight under 1 gravity = 887,814,083.9 kg pretty damned heavy, right. But in reality it's not going to be solid metal, though it would make an awesome wrecking ball if it were. We would want it to be heavily armoured so lets say the shell is 30 cm thick solid steel. The inner empty sphere then has volume of 109738231.6 litres. The volume of the shell is 113097335.5 - 109738231.6 = 3359103.9 litres Under 1 gravity the sphere would weigh 26368966.1 kg Density = mass divided by total volume Density = 26368966.1 kg / 113,097,335.5 litres = 0.233 kg / litre Density = 233 g / litre Less dense than water, less than the density of a human, it would float on water, just like a ship. A man squashed into a ball would not float as well. Now it's mostly empty space, so that leaves a lot of room inside to put some very big engines, which of course it going to need and of course they are going to increase the weight but even if they weigh as much as the hull, it's still going to be a lot less dense than a man. A sphere is the best case scenario but the same logic would apply for any shape as long as it's mostly empty space - give it solid hammer fists maybe but keep it mostly empty everywhere else. Would the metal fail under it's own weight at that size, thickness and weight? I don't know - ask an engineer. If steel couldn't take the strain are their any alloys that could? Or substructures within the steel that would make it stronger? If the independence day aliens could solve the problem and build an intricately designed mothership with mass equivalent to quarter of our moon's (so over 10^19 tons - they must have built it using degenerate matter from a collapsed star) that somehow didn't collapse in on itself, hopefully we can solve the problem for a comparatively lightweight materials like steel. Then again why bother, hurling a giant wrecking ball weighing 887,814,083.9 kg at your enemy is going to do more damage than an army of giant mechs, if it connects. Better not miss though because it won't be easily retrieved. [Answer] Intimidation could be an advantage. A mecha could serve as a symbol of military superiority. Also take into account the psychological impact of seeing a giant metal humanoid towering over a defended area vs a tank. The tank is still intimidating but a giant humanoid shape would tap into a primal fear of someone being much larger and stronger than you. It probably wouldn't be worth the cost to make an army of large mecha but if a few were made and used strategically they could be useful for crushing enemy moral [Answer] Who says 2 legs mean you need to walk? **Hopper.** [](https://i.stack.imgur.com/8bwOr.jpg) <http://www.montananaturalist.org/frog-jump/> The hopper can go places a wheeled vehicle cannot. It can go places a walker cannot. It can throw itself over impediments blocking the way of wheels and legs. It can throw itself over holes and trenches. It can soar up, shoot from above, then land and hunker down. Using large surface area feet that unfold like umbrellas, it can move along the tops of trees or across swampy areas. The movement of a hopper is difficult to predict and so it is harder to hit. Downside: your mech does not look like a badass giant samurai. But your pilot can still wear a badass samurai costume if you want. [Answer] There were advanced mecha (humanoid robots; about the size of a person and remotely controlled) in a book called *Gamer Army.* Since bullets could (and *did*) hurt these mechs, and missiles would do the same (but worse), why would these mechs be viable in combat? For the same reasons already posted, and a few more: 1. Agility-Tanks aren't good on truly rough terrain. Gravel is fine, but when the ground is covered in big, jagged rocks? Treads are useless. Tanks also can't climb stairs or walls, and they can't *jump!* 2. Versatility-Tanks can't do anything besides ram you or run you over once their ammo's depleted. 3. Critical Reasoning-The antagonist's idea for quelling opposition to his radical ideas was to upload the best gamer's consciousness and download it into an army of his "Viper" mechs. A similar idea (housing a soldier's mind inside a battle-designed android) could create something that frankly, I'm not sure a tank can overcome: *faster critical reasoning.* A machine's greatest strength lies in decision and execution; it can recognize a need and execute the needed action far faster than a human being, but it can't imagine worth a darn. No, seriously! From personal experience with coding, Grammarly, Google Translate (there are others, but those are the best examples I can think of off the top of my head) I can tell you computers have little to no creative ability, interpretation and otherwise. This is why humans still have a place, and will *continue* to have a place no matter what: *we* can think creatively, but computers really *can't.* However, this is also a potentially lethal weakness of tanks. Transfer a human consciousness into a humanoid robot, and you have human creativity and (mental) adaptability in a far more capable brain and body. In other words, the tank will have to overcome: 1. Someone who presumably knows the strengths and weaknesses of a tank and how to overcome them, who can think and act far faster than its operators can 2. Someone who is better armed (since a robot can carry heavier weaponry) and defended (since a robot can carry better armor and be much, *much* tougher than a human) 3. Someone who is more agile (can handle more terrain than a tank, is more maneuverable, Finally, here is a paragraph from mwi.usma.edu (Modern War Institute at West Point): "Ever since modern tanks’ first appearance on the twentieth-century battlefield, infantry forces and their armored counterparts have been engaged in a sustained arms race with one another. Improvements in antitank weapons led to armor better able to withstand them and vice versa, with pendulum swings marking the temporary advantage of one or the other. In recent years, the balance rested firmly on the side of well-trained infantry with both advanced guided missiles and unguided rockets. The greatest of these capabilities are fire-and-forget, guided, top-attack missiles—the premier model being the American-made Javelin. This weapon allows a single soldier to target and destroy even the most heavily armored main battle tank with an almost guaranteed kill rate, at great range and with minimal risk." Give a mech Javelin missiles, and I don't think you'll have a plausible reason *not* to use a mech of the kind suggested here. They are, after all, superior to infantry in almost every way, and last I checked, tanks can't outrun missiles and have very vulnerable treads..... [Answer] There is one thing missing in all the answers : all weapons always change in reaction to enemy. Modern values in warfare turn around the idea, that you are going to fight fellow human with similar level of technology. This means battles are waged at long distances and with idea of air superiority. But imagine enemy, that is able to deny you the air superiority and that would be able to quickly close that distance even after hard shelling and still be able to trample you. How is tank helpful when you have 5 big-jawed enemies 5 meters away and closing? How is jet helpful, when both his wings are gone? But what if you had a mech, that can use jets to hover 5m above the ground, move quickly around and get in and out of enemy group to be able to strike into enemy's back and while using the enemy itself as a shield? Exactly how [mechs](http://muvluv.wikia.com/wiki/Tactical_Surface_Fighter) work in [Muv-Luv](http://muvluv.wikia.com/wiki/Muv-Luv_Alternative). [Answer] First off, mechs with arms which are most commonly referred to as a gundam styled mech, uses opposable arms which match the shape and combat style of people. But by mimicking the shape of a person, that limits the possibilities a single mech can hold. Keep in mind the mechanics that are required for functional arms and legs. By mimicking people, the arms will have a limited carrying weight. The legs which would be limited by the over all weight of the mech and arms, plus whatever is equipped to the arms. This is a lot of hydraulic strain for two legs plus the arms. So gundam styled mechs, while possible, would be not be helpful on a battle field. Some mechs could have arms that have little to no movability. This means less hydraulic strain on the arms and more strength can be focused on the legs. Not to mention, if body no longer goes by human shape, mechs could have a tank like, turntable torso, which allows for 360 degree visibility, as well as quick utilization of weapons instead of turning the head to look, and then the torso to react. The torso contains a lot of important electronics and equipment like the reactor, and all the main electronics to deliver power and hydraulic fluid to all the parts of the mech. Then the legs, which supports literally every part of your mech. They need to be VERY strong. The strength of the legs is what will limit what can be equipped to each mech. On the left and right are the arms or weapon pods. Mechs don't have to have arms. The best example of this is the UrbanMech. (Picture below) [](https://i.stack.imgur.com/daNkd.png) The arms will most likely be where the majority of your weapons will be located, as well as maybe one or two on the torso. With both arms having weapons, one can be sacrificed to keep harm from the torso and cockpit. Now, with size and speed differences of each mech, there will be separate classes. There are light, medium, heavy, and assault mechs. Light bots would be small, fast, and have small weapons. They are commonly scouts, or deployed in groups to take out heavy and assault mechs. They could usually outrun most larger mechs if need be. [](https://i.stack.imgur.com/vxeAi.png) Next are medium mechs. These mechs are used to fill the gaps between the small and fast, and the big and strong. They would be used as foot soldiers mostly, but can fill a variety of roles. [](https://i.stack.imgur.com/SwfW7.gif) Then there would be heavy mechs. These mechs would be slow, and very, very tough. Their size often hinders them against light mechs. They could carry heavier weapons than most mechs. [](https://i.stack.imgur.com/XpD8H.jpg) Then there are assault mechs. They are about as heavily armored and slow as heavy mechs, but can carry more weapons instead of just bigger ones. Once again, someone in a proper light mech can out speed them, but just like heavy mechs, they are best taken down by at least a medium mech. [](https://i.stack.imgur.com/sKdbh.png) And that's pretty much it. The real world application of mechs such as this could be limitless. They carry, and can survive hits from weapons way larger than what is carried by a tank and survive bombardments of missiles. Sure two legged robots are usually unstable, but look at not only how big they are (it would be hard to knock them down with really anything) and the base of their feet are quite large. While they would cost more than most other vehicles of war, all other ones would really become obsolete. A simple AMS (Anti-Missile-System) could defend against anything airborne, while enormous guns would enable the mech to protect itself. The engineering is there, but the military hasn't put forward the effort to make these war machines reality. They could be more dangerous than anything we have ever created. ]

[Question] [ I'm writing a traditional fantasy novel (minus the cliches). I have a land that the novel takes place in. The land does have a name, which sometimes sounds all right, but most of the time sounds kind of stupid. Being the author, it might just be me, but I was wondering if there was some way I could ensure the name of my land would reflect the style and theme (in this case, noble and majestic) like I want it to. I'm not talking about names like 'Middle Earth' which simply use English words. I'm talking about a completely made up name, like Paolini's 'Alagaësia,' So here's the question: is there some formula or rule I can follow to make geographical names sound similar and unique? POST-ANSWER EDIT: I've marked the reply by James as the answer. I think for those simply looking for a good name, this is a great way to go. However, the answer by Durakken is also a great method, and will hold up in the event that your novel is the next Harry Potter or Lord of the Rings. It takes more time, but it is a lot more thorough. And if you get stuck, you can always uses James' method for inspiration. Additionally, the answer supplied by Bookeater is a great method to test the names once you have them. After going over names in your head for so long, it can be helpful to write them down and have someone else read them to you. Remember, if they pronounce them wrong, just alter the spelling. The real name likely isn't written in English, so all you're doing is translating it. You just need to make sure it is pronounced correctly. [Answer] I would recommend [google translate](https://translate.google.com/?hl=en&tab=wT) for this little effort. * Pick a language that fits the style of your world/or a particular nation depending on your scale. This mainly means find a language where the sound fits the world's setting/style * Pick words with meanings that fit and then use the one word, or perhaps splice two or three together. Once you do this you can optionally also add -polis -ville -burg -shire -ton or something similar if you want to give it a certain English language familiarity as a city name suffix. **Example:** Say you have a city on a mountain. It's a pretty magical world with a serious tone. So in this situation let's go with Hungarian (I like the sounds of this language): Mountain top = hegytető Stone top = kő tetején City = Város Citadel = Fellegvár State = állami **So from these, and there are a ton of options here that are obviously not included, we start combining:** Hegyros (Mountain top city) has a certain ring to it Ko'aros (Stone City) Kotetvar (Stone top citadel) I could keep going, but hopefully this illustrates the process. [Answer] The reason fantasy names often sound weird is that they violate the way we normally handle names. The Romans didn't call Ireland *Éirinn*; they called it Hibernia. We don't refer to the Irish name [Aengus](https://en.wikipedia.org/wiki/Aengus) as Oíngus but as Angus. Human cultures adapt names from other languages into names that sound more comfortable to their ears. Unless your entire work is written in a fantasy language, you are probably going to be writing in an existing language, so your names need to sound comfortable to the language you are writing in--this means they need to be composed of parts often used in that language. The exception is if you want to give the impression that the names are foreign to the central character. For example, the hobbits and humans are the central characters of the Lord of the Rings, and so their names sound familiar, if a bit archaic, to English speakers: Aragorn, Bilbo, the Shire, Gondor. Elven and dwarven names sound more distant: Thranduil, Galadriel, Lothlorien, Gloin, Khazad-dum. This is because they are supposed to feel foreign from the perspective of the main characters. **Example of constructing a name comfortable to English speakers:** Hell -> Hel Dim -> Dem Hel + Dem = Heldem You construct the name out of sounds of existing words, and now you may even have an idea of what the name means in your world. [Answer] *Basic short-cut:* Recite your name out loud. How does it sound? How does it sound if you repeat it ten times? How does it feel when it rolls off your tongue? *Seek multiple input:* You can ask other people the same so you can 'hear it back' and assess what they make of it. You can give the name on paper or tell them the name. From paper any ambiguity from written word to sound will reveal itself, which may both subtract and add to the character of the name. If you do this you will find that some names are forgettable. Drop those. Other names will stick. That is a good characteristic for what you are looking for. If the people who tried it still remember it the next day you are on to something. Some people will like one name, others another. Some names will be fun. Some names will be bastardized into something else immediately which may be an improvement... or not! I think if you make names come alive through the human voice some will just sound louder, deeper, better. Have fun! [Answer] The way to create a "real" name is that you have to create a language. Then give the land a name like "Land of Blah" translate into whatever language you just made up then apply language changes to your language that happen over centuries and cultural changes. For example "Blahland" may become "Plahan" or "Vlahad" or "Fraat" because it mutates from language shifts and people simply dropping sounds to make it easier to say. This sounds a lot simpler than it is, but hypothetically you could just do what I did, which take English and apply very loose lingual changes and get an acceptable sounding name. Also remember that these changes repeat so "Fraat" can become "Vleth" and then "Land of the Vleth" or "North Vleth" which then goes through this all again. "North Vleth" probably would become "Norvleth" due to the "v" and the "th" doesn't sound right together "Land of the Vleth" might be structured as "Tal Vlethia" where "Tal" is an article mean "The Vleth" and "ia" means "land of" The only thing that is important is consistency across languages so that you get consistency which is why you'll find lots of places with the same suffixes like "-ham", "-shire", "-ton". I don't do it this roughly, but for most people this will be good enough. I like to try to make whole new languages and their language trees ^.^ which is incredibly difficult and a painstaking thing to do so if you're not looking for perfect accuracy, what I told you is good enough, with perhaps a little bit of research into what sounds will transform into others, to get you any name you need for a place. [Answer] Take a name whose rhythm you like, and replace each phoneme with another of the same broad kind. Thus *Ruritania* becomes, say, *Lanucomia*: the unvoiced stop became another unvoiced stop, vowels became vowels, liquids (including nasals) became liquids. (I kept the ending *–ia* because it effectively means ‘country-name’.) It shouldn't be hard to write a short program to spit out a hundred random “encipherments” of the input name. You'll need these sound classes: * vowels {I,E,A,O,U} * voiceless stops and affricates {P,T,K,Ts,Č} * voiced stops and affricates {B,D,G,Dz,Dž} * semivowels, liquids and nasals {W,Y,R,L,M,N} * fricatives {H,F,S,Š,Þ}, {V,Z,Ž,Đ} ... and others if you want to go more exotic. Cull by hand those with impossible phonotactics, e.g. *čl* as a substitute for *tr* – or try reversing the order of such consonant clusters (*lč* is more likely, after a vowel). [Answer] This is very difficult to answer. Names that are wonderful for you may sound boring, or absurd, to someone else, and conversely. Especially if your work is translated, or if foreign readers read it, even in the original. But anyway... let's try. First rule, toponyms are frequently combinations of geographic features, often mixed with anthroponyms or names mythological creatures. If your fantasy land has its own language, you will have to create it, at least as a "naming language". Have a list of words that mean things like, * town * river * hill * sea * ford * etc. plus words for things like colour and dimensions, and a few anthroponyms, names for gods, and, oh, I forget, positions in social hierarchies. This would give you the equivalents for places like Deepford, Bluesea, Kingslanding, Marytown, Venushill, Capetown, etc. Then add a few toponyms that no one (except etymologists, who are rare in fantasyland and moreso in thrilling adventures) really knows what mean (such as "York" or "Talahassee"), and presto: you are ready to name most of the places you need to give a name. Of course, if you make, let's see, deep = brunka, and ford = forry, you will get Brunkaforry, or Forrybrunka, for Deepford, so, second rule, Make your name composition elements beautiful. Which is the really subjective part. But there are a few tricks. One is, a few languages have high social prestige, because knowing them denotes a higher education: Latin, Greek, Hebrew. Others have a feeling of ancient things; in a British setting, those would be Celtic, Norman French, and again Latin. Still other languages are reminiscent of exotic mystery, such as Japanese, Arabic, or Nahuatl. And others have a flavour of adventure and violent conquest, such as Tupi, Narragansett, or Bantu. So use features of these languages to subliminarly convey these ideas. In Iarunus or Elmabeb, expect to find high, perhaps forgotten, knowledge. You will find ruins of ancestral people in Laboné or Llantordiff. People from Tamekana, Halabal or Tentxatl will have different, perhaps extraordinary, belief systems. (Bonus for human sacrifices in Tentxatl.) And so on. I know, this is probably part of what you call cliché, but you can be more subtle than these obvious examples. Distort more, make the references to real languages less obvious. Or else play the clichés intentionally; make Polismena a hillybilly backward town of inbred violent pitch fork carrying idiots, and Xomalqlitl an enlightened metropolis of great philosophical wisdom, vibrant commerce, and technological inovation. And, of course, read other fantasy (and non-fantasy) authors, and see what they do. Why are Bree, Syldavia, Cair Paravel, Hogsmeade, Platiplanto, Atlantis, better names than Allagaësia? [Answer] Here are some links to helpful generators that I often use; * <http://fantasynamegenerators.com/country_names.php#.V5ej2vkrLVQ> * <http://www.namegenerator2.com/country-name-generator.php> * <http://www.springhole.net/writing_roleplaying_randomators/fantasykingdomnames.htm> [Answer] A nice little strategy I've used for a while to come up with cool-sounding but totally fake names is thus: **Find yourself a cool meaning** I like to visit [this page](https://en.wikipedia.org/wiki/List_of_spacecraft_in_the_Culture_series) for cool names, but of course this is subjective and you can choose whatever you please. Let's pick the name `Just Testing` from that page. **Translate it into a non-Latin language** This is to get letters which don't exist in Latin based languages, my go-to is Greek, but Cyrillic or Asian writing systems work just as well. The translation of `Just Testing` into Greek turns out to be `απλά Δοκιμές`, or the Latin spelling `aplá Dokimés`, using good ol' Google Translate. Accurate translation doesn't matter. **Anglicise it!** Clearly, `aplá Dokimés` contains characters not used in English, and looks nothing like the original `Just Testing`. My usual (lazy) approach is to cut all the accents and mash the words together, leaving us with `Apladokimes`. This is a great base that you can name anything with, and you can come up with the pronunciation too! For this example, I'd pronounce it as `Ah-Plah-Doe-Key-Mez`, but that's just how I read this totally made up word. Hope I've helped! (**Fun fact:** this is how I came up with my username!) [Answer] Well, this depends a lot on your stylistic approach. Many settings use names that "sound" like they come from a particular fantasy race, like so: *Elvish*: Aularia, Estrooa, Yorial - flowing vowel-y words that sound... soft? *Dwarvish*: Raugh'laughan, Oshlairn, Bi'varsk - "harsher" sounding words, typically sounding German or Nordic in a sense. *Orcish*: Blavik, Shar'ziv, Moktak - also harsher, usually uni- or bi-syllabic and guttural sounding (like a stupid Orc could manage to speak natively). Obviously, these are probably pretty awful examples just off the top of my head, but they fit sort of an expected theme for cultural/racial words and names that we have for fantasy creatures. If you have such a creature and want the reader to feel comfortable with a racial language-based name from some well-known fantasy race, go that route. Look at other names of places and characters of those races in other fantasy works and derive something from those. If you are using unique creatures, find a unique sound. J. R. R. Tolkien is basically the grandfather of our concept of Elvish languages, granted he actually created entire languages for his works, but if you want something to be completely unique, go for unique - but you'll still want something as a baseline. Even if it's something that "sounds like Russian and Chinese smashed together" or "sounds like English spoken between two grinding rocks" or whatever makes sense to you... then play with words, write a bunch down see what works and what doesn't, the evolve words from there. [Answer] The name of the land in a secondary world (as it is in any world, frankly) is tied tightly to the language that nation or race speak. While it is probably safe to assume that your story is written in English, the native tongue of the people inhabiting your world/country/region is likely already leaking into your narrative through names of your characters (have you named those yet?). You probably have an idea of what their culture is? Is it similar to any of the known ones? You can hint on the similarities, using similarly sounding words. Imagine what would their language sound like. What do they would call a sword in their language? What would they call a city? You do not have to invent the whole language, just imagine what would it sound like to a foreigner. Needless to mention, that the Emperor of Alagesia will likely not be named Bob. And vice-versa, High Priestess Ch'kamadarsta does not reside in Jerktown, unless she is a refugee immigrant. There is a slew of name-generators on the web, all have different features. I had moderate success with this one: <http://rinkworks.com/namegen/> despite outdated looks it is actually very flexible, and even allows you to create a unique custom template for generating names based on choice if characters. [Answer] This might be a little weird, but I've used this method of generating names for D&D characters and other characters I've needed. As a human, you can't quickly generate a lot of completely random names off of the top of your head, but you *are* good at making/finding patterns in randomness. The first step is to just mash your keyboard for about 20-30 characters, to get something like `cswnjkdrepuiecgbyiysrcgoimaiv`, then just read through it repeatedly and draw out patterns that form names. From this I got: * Goimav * Drypui * Quigby * Cyswen * Wyndrey Some will be better than others, but you will be pulling out words that 'sound right', as you will be automatically trying to match what you think sounds good (at least, that's the idea). Repeat this process a few times and you'll end up with some good names. If what you get doesn't work, just try again. It doesn't take too long to do. [Answer] ## Spend time imitating various languages out loud Listen to foreign TV or Youtube videos. Try to repeat real sentences, even though you don't have any idea what they mean. Also, just make up words that sound like they could come from that language. I find this is also a great way to improve your pronunciation of foreign languages you're learning. Make sure to try languages from different parts of the world, for instance, Arabic, Mandarin, Russian, Spanish, Hindi. This helps you to play with totally different patterns of speaking—some with many consonants, others with more vowels; some very free-flowing, others more punctuated; some with short words, others long; some with a fixed rhythm, others with an organic rhythm, others with no pattern; some melodious, others discordant. (As a side note, using a name that sounds like it is from a particular language immediately gives the reader a strong idea of the geography and culture of a place. For instance, "Al Hazaab" sounds like a desert city, perhaps a trading hub; "Masetas" sounds like a regal, pious city.) ## Decide what sort of language "feels right" for your people Start making up words and sentences that you feel "fit". Put yourself in the head of an official reading a proclamation. Of someone gossiping. Of a leader trying to inspire his people. Don't worry about making mistakes, or things that sound wrong, or getting repetitive. When you notice this just make an adjustment and keep going. I find that sometimes while doing this, I get plenty of useful "words" that I can string together into a name. Record yourself or write things down if you like. Sometimes, though, when looking for a name that is "just right", I proceed to the next stage: ## Start somewhere, then fiddle Choose a letter or sound to start your name. For instance, "Ba". See if you can find a nice way to continue it. If you can't, try a different beginning, like "Bo" or "Ma". You might come up with "Magretta". Then try replacing bits of this with something else: "Segretta", "Magretava". Use what you have decided "feels right" to help guide you. Repeat this process many times. Mix and match. Yes, this progress does take a while but you may be surprised what you come up with. Don't forget: * Not all sounds can be broken down into single letters. Play with sounds like 'sh', 'ch', 'gh', 'ee', and final 'e's. * Some place names are made from multiple words. ## Consider adding some history Some of these have already been mentioned, but: * Places that are named after gods / important people * Place names that have some meaning in one of the languages of your world * Places that are called different things by different people * Place names that evolve (typically get shortened) over time A lot of places in the real world end with 'land', 'ford', 'ville', 'burg', 'grad', etc. because of the meaning of these words in various languages. If you create some words to mean things like 'town', 'city', 'river crossing', and employ them in some or all of your place names, your readers will start to appreciate the meaning even if it is not made explicit. [Answer] KISS principle (keep it simple/stupid) Come up with something long and clever and then find ways to abbreviate it and keep abbreviating it until you're down to 2-3 syllables, the is the name of your fictional country in common parlance while the original is the formal or historical name. Australia = Oh'straya [Answer] Well, when it comes to fantasy, there is more work than meets the eye. You see, usually, well-known fantasy lands have languages, culture, history, etc. with them. Like, for example, J. R. R.'s, "Hobbit" series has fantasy languages or *conlang.* Conlang means constructed languages if you mind. Anyway, it might help you a TON if you make your own language for this land. It will help both you the writer, and it helps the story deepen with, "juicy details." OR, if you don't have enough time to make a language, don't know where to start and you are *completely* confused, or you are just plain out lazy, here's this idea. Most cities either have, "opia," "a," "ton," or other suffixes along that list. After that, put one or two at the end of the name (Optional!) After that, you can pick out some constants that you like. For example, I'll pick, v, l, and s. Now, pick some vowels. I'm gonna pick, I (or ii to make it more, "spicy,") A, and I'll throw in o as well. Now, mix it all together! I got the word, Viilasoa. If you like the sound of the lump of letters you just created, dub it onto the region of lang you want the land to be called. If you don't, then you can take the word and (wait for it) you can translate it into other languages! Like, in another language, your word might mean, "sheep!" Anyway, In EVERY SINGLE language, there was no change. Welp, guess I'm stuck with Viilasoa...Anyway, that's the best I can put it in words, :D. [Answer] ## About names All names seem to have meaning. Likely people won't commit to them unless they do. After some centuries they keep committing out of tradition even though the meaning of the name may have become archaic or even lost in history. This means you can invent whatever name you want and claim its meaning is "lost". However, I think applying a system is more fun, more logical, and may even give you a bit of a free ride when parts combine to new wholes (so read on!) Some examples of real-world names: * **[England](https://en.wikipedia.org/wiki/England)** - Derived from a people called the [Angles](https://en.wikipedia.org/wiki/Angles) (from Germany/Denmark) * **[France](https://en.wikipedia.org/wiki/France)** — the realm of the [Franks](https://en.wikipedia.org/wiki/Franks), makes more sense in german(ic) language(s); Frankreich (reich=realm) * Which brings us to **[Germany](https://en.wikipedia.org/wiki/Germany)**, a name the Romans used for the land of the germanic tribes (Germania). **Deutschland** however is more about the "land of the people" than germanic tribes per se. * And to not be completely eurocentric, **[China](https://en.wikipedia.org/wiki/China)** probably named after the [Qin dynasty](https://en.wikipedia.org/wiki/Qin_dynasty) (or "Ch'in"). So if you were to use English you'd create a people (ancient?), transform and bastardize their name some, and give them a land (or look into the etymology of other counties to get other ideas). To make it more interesting you could use other words than land; mark, realm, etc. You ask about making up names, and for that, you could either invent a people (Ch'in) or use a conlang. ## Conlanging As shown above, to create a name for one nation, one needs a few words in a conlang: One for "land", one for the name of a people. Or an expression that can be compacted into a word for "the land of the people", or maybe even "the people's" or "the land". Or just a name of a people. Or, one can go the complex route and create many names using several conlangs... I created conlangs for names of countries, cities, and for given-names and surnames. (Actually, I created programs to create words for them randomly, with varying success, but going that far takes us into conlanging instead of name creation, see [here](https://donjon.bin.sh/name/markov.html) for a simple example). At first, I just threw randomly created words at country names, place names, as well as people names. Then came my realization about meaning, and I started researching it and found that most names seem to follow a system. Here are some examples from Sweden (where I'm from): * [Stockholm](https://en.wikipedia.org/wiki/Stockholm) - logs (stock) and island or islet (holme) * [Gothenburg](https://en.wikipedia.org/wiki/Gothenburg) (Göteborg) — fortification (borg) by the [Göta River](https://en.wikipedia.org/wiki/G%C3%B6ta_%C3%A4lv) * [Malmö](https://en.wikipedia.org/wiki/Malm%C3%B6) – from "Malmöghae" piles of sand or gravel (and surprisingly not, as one might think from ore [malm] and island [ö]... — goes to show you a realistic etymology of names can be messy...) See [here for a more general disussion](https://en.wikipedia.org/wiki/Place_name_origins). [The United Kingdom](https://en.wikipedia.org/wiki/List_of_generic_forms_in_place_names_in_Ireland_and_the_United_Kingdom) is an interesting example where names are built by elements from many different languages (a dozen or so on the linked page). You can easily see a system of types of words used in place names. Once I realized I wanted names with meanings, I started assigning conlang versions to the examples from the UK system (and the [Swedish](https://sv.wikipedia.org/wiki/Ortnamn_i_Sverige) system—the link is in Swedish though, and the English Wikipedia article is not compatible... Google Translate might help, but it may also mess things up, but then again, this is conlanging... regardless, the big difference is in some details and the larger number of languages used in the English version.) So I assigned a conlang word for "large church, monastery" and another for "West" and I could create my conlang version of "Westminster" or why not "Northminster"? (Extra interesting if you don't have churches or monasteries but maybe sacrificial groves or rain dance rocks, etc) People's names are a bit trickier, and here I've used random words for given names and systems similar to the above for last names (occupations, features of nature, etc, [this Wikipedia article](https://en.wikipedia.org/wiki/Surname) covers lots of different ways to create surnames). ## Meaning My experience is that names chafe when they don't have meaning. Inventing fantasy words in conlangs can result in really cool names, but as a writer/world builder it can feel a bit unfinished to not know what the name really means. If you apply the systems our human brains have invented to add meaning, it can become even cooler. Not to mention how handy it'd be if you get cornered about the meaning of your names... [Answer] If you are creating in-universe language choose the name according to this language. It may soud weird for you, or the reader, but it is part of the universe, you've created. I don't think that names like Krč, [Spálené Poříčí](https://translate.google.cz/#cs/en/Sp%C3%A1len%C3%A9%20Po%C5%99%C3%AD%C4%8D%C3%AD) (let the google read it for you), [Eyjafjallajökull](https://cs.wikipedia.org/wiki/Eyjafjallaj%C3%B6kull) will sound nice for everyone's ear, but they are real names. In general, there are meaningless names, like Hrs-hgn (Terry Pratchett: the Dark Side of the Sun), punny names like Dnah, Hctib Elttil (Lar Desouza: Looking for Group),... So, don't bother it sounds weird. If it fits to the universe and the story it is all right. [Answer] One of the innovative ways I have seen things named is the way Chinese deals with proper nouns. Any novice student of Chinese can tell you that each character has one particular meaning (although the overall meaning can change greatly when you mash characters next to each other, sometimes quite intuitively!). However, at least in Mandarin Chinese, there are very few morphemes (single-syllable sounds) compared to the number of characters, which means that "shi" alone can mean hundreds of things! However, when it comes to actually naming places, things get tricky. For example, New York becomes 纽约 - prounounced "**Niǔyuē**". The actual characters refer to "button/knob" and "agreement," respectively. To me it make sense, because it makes me think of people pressing a button on an elevator to take them to the floor where the business people make business agreements. But literally, Chinese refer to New York as "Niǔyuē" because it kinda sounds like New York. Close enough. However, that isn't the only way to name things. Hong Kong (香港, or as mainland Chinese say, "Xiānggǎng") literally translates to "Fragrant Harbor." Makes sense, right? It's a harbor and they want to put a good spin on it. Bam! But that's already a Chinese city! What happens when they try to Chinese-ify a foreign city whose name doesn't match any existing Mandarin morphemes? Let's try San Francisco! In Mandarin Chinese, San Francisco becomes 旧金山 ("Jiùjīnshān"). This translates literally to "Old Gold Mountain," which is logical, because San Francisco is remarkably mountain-like, and it got its big boost from the California Gold Rush, so the name stuck! To wrap up: you can create names by using foreign translations that either use literal meaning or sound-alike words. Character-based languages like Chinese and Japanese make this a lot of fun, and you can add a lot of deeper meaning within them, although alphabetic languages can also be used. It all depends on the "feel" of the names that you are going with. If you are looking for a Tolkeinesque elven city name, for example, you may want to try Gaelic. [Answer] You might actually consider names already established in culture and use them in related or novel context. In my opinion, a part of good fantasy/sci-fi book is discussion with existing cultural heritage, not essentially coming up with everything all-new. Some nice examples can be found in The Witcher book series, for example, we have a banking institution run by [Vivaldi Brothers](https://en.wikipedia.org/wiki/Vandino_and_Ugolino_Vivaldi). ]

[Question] [ On [our world](https://worldbuilding.stackexchange.com/questions/139907/what-species-should-be-used-for-storage-of-human-minds), human minds can be transferred intact into animals. It was originally intended for people with medical conditions, but [some genius](https://worldbuilding.stackexchange.com/a/139995/20872) thought it would be clever to store violent prisoners as fish, in large tanks. Well, it's because the prison had two *salmon doctors* due to their sideline activism in fish-habitat restoration ([trying to](https://en.wikipedia.org/wiki/The_Monkey_Wrench_Gang) blow [up a dam](https://en.wikipedia.org/wiki/Night_Moves_(2013_film))). So, for their docile animal, the prison selected atlantic salmon, 13 year lifespan, and the minds are re-transferred as needed to young healthy fish. Then, the hurricane or tsunami came. Having thought of, planned and practiced for a similar escape plan, the prisoners knew exactly what to do. They used the storm surge, and the absolute chaos on the human side, to slip their pens and escape to open ocean. Now they have their human knowledge of geography and full access to any ocean on earth, access to inland waterways that are not blocked to fish, and the knowledge to navigate locks when humans open them. Salmon can operate in both salt and fresh water. They have worked out communication between each other and it is effective. Remember, they are human-smart, and nobody needs to explain the Prisoner's Dilemma to them. They have team defenses against birds and other predators. The two salmon doctors are respected as leaders, and have prepared everyone well for life outside. These prisoners are not going to die of stupidity/not knowing how to be a salmon. Now you have a gang of human-smart, human-experienced, very vengeful salt water/fresh water fish who want to cause civilized society as much trouble as possible. What harm could they do? ## Followup Q&A **Species substitution is absolutely fine**. The lore could simply make them *the other kind* of sea life scientists. (I chose salmon because it fit the dambusting story). The [original question](https://worldbuilding.stackexchange.com/questions/139907/what-species-should-be-used-for-storage-of-human-minds) posited "animals generally" and established that human brains *will* fit somehow. Feel free to armwave past some physical limitations like salmon's poor eyesight. (If smarts can fix the Hubble lens, why not a salmon eye?) Blend in salmon abilities as makes sense: they can perceive it, perhaps they can learn it, and they have competent teachers. The human brains have full memory of their previous lives, so they know where Jimmy Hoffa's body was sunk, the layout of the canal system, and when the refinery shuts down the heat exchangers for maintenance. Would they use the storm surge to swim around the city to cause landside mayhem; nope. They are terrified the water will recede at any moment, and they don't want to end up gasping on a sidewalk. Their only plan *during* the storm surge is to get to open ocean. Their dream made real, only now do they scheme. Only reluctantly would they suicide; they'd look for technical ways to not have to die. Maybe they can train real fish to die for them, or use a biological mechanism as a timer. Communication with each other is efficient. Communication with random humans is *comedy*. A few guards at the prison trained up to have struggling *direct* conversations, but may have developed a more precise scheme like a ouija board painted at the bottom of a pool to communicate with the *scientists*. Any random prisoner would have trouble snitching. The prison has no idea they *planned for* a storm surge escape, and they actively search and throw together fish-activatable mechanisms to signal "I have returned, please help me". That means they could stay away for awhile and still return. Returnees would probably be turned back into humans and debriefed, and to a man they would give well-practiced fish stories of how difficult it was to return and how they barely escaped with their lives, to avert escape charges. This might be a consideration in their plans for mayhem, better for them if they can conceal that smart salmon did it, "what could I have done? [I WAS A FISH](https://www.youtube.com/watch?v=N4XAUdxfF3Q)". As to why they'd risk a <<13 year life in the wild, freedom is like that. Maybe not all do. None will rat out the plan. The prison is not the only one who can port them into better bodies, but moving into a non-fish body is beyond the scope of *this* question. Do the prisoners need to actively manage all aspects of salmon life - probably but not sure, see the [earlier question](https://worldbuilding.stackexchange.com/questions/139907/what-species-should-be-used-for-storage-of-human-minds). They will bring human skill and teamwork to every problem including feeding. [Answer] ## Make someone overreact So you swim to North Korea (hopefully the tank was not too far). Once there, you regroup in the shape of a submarine and you slowly approach any US/Japanese/Chinese/North Korean/South Korean warship you can find. Hope someone overreact and press the wrong button. If not, try again. ### Playing with nerves Also every time you see soldiers on small rafts in the area, you capsize them and make them disappear to the bottom of the ocean. This will help people press the wrong button sooner or later. This kind of boat or smaller would probably be possible to capsize by a sufficient amount of well coordinated salmons: [](https://i.stack.imgur.com/j0OyB.jpg) ### The holy grail There is one thing that if you can manage to find, will help you achieve your goal much faster. A water mine! Maybe there will be some in proximity of some secret North Korean's navy facilities. Find one, bring it in the path of any large warship in the area, and swim away fast. [](https://i.stack.imgur.com/8gD3h.jpg) ## Escalation Then let's relax and watch the **escalation** of violence turn into a nuclear war, naughty salmons. [Answer] **Let's shut down and/or melt-down some nuclear power plants.** Heck if [some brainless Swedish jellyfish could do it in 2013](https://www.theguardian.com/world/2013/oct/01/jellyfish-clog-swedish-nuclear-reactor-shutdown), surely a gang of criminal salmon can manage! [Answer] > > What harm can they do? > > > Not much. They lack arms/hands and legs/feet. Their ways of communicating will be limited, and whatever they come up with according > > forcing them to work together to learn to communicate > > > that will be some form of communication which works for the giants fish tanks they're being held in. Not a vast ocean. Besides, most species of salmon only live a few years. The longer the prisoners/salmon had to make plans, the elderly they are. It's far more likely they will quickly end up as food, or succumb to parasites. [Answer] Well, I'm sorry to say, but the world as you know it, is in deeper trouble than you think. The fishes just need to follow a simple 2-step process. ## Step 1: Try to get back into a human body. Given that [*"The business of mind storage [has] become a profitable one"*](https://worldbuilding.stackexchange.com/questions/139907/what-species-should-be-used-for-storage-of-human-minds), it would be fair to assume that the technology to do so would be fairly easily accessible. So our fishes just need to find an ally, and convey to them that they need to be transferred to a human body! *The ally could be their evil friends outside prison who are still escaping the law-enforcement, or could be a rogue nation who wants to hurt rest of the world.* I'm sure the fishes have had enough time to identify potential help, and ways to communicate their message. ## Step 2: Cause mayhem (with your human bodies)! [Answer] Your super smart Salmon want to cause chaos so what they do is abduct highly aggressive species and forcefully migrate them into environments where they have an abundance of food and not many natural predators. Eventually the ecosystem in these areas are ruined leading to a collapse in the supply of seafood causing seafood prices to spike and the lack of diversity causes tourists to avoid the area leading to the general decline of coastal towns. [Answer] I think the key is to stop thinking like a fish....it offers them very few advantages. The only thing they should worry about as salmon is how to stop being salmon. Head to a touristy destination where people rent canoes or kayaks and make a coordinated effort to cause one of them to drop their cellphone. Many phones are waterproof to some reasonable depth and it seems more and more will be in the future. Now you have a cellphone. In a group of violent criminals, certainly, they would have at least a few reliable criminal partners "on the outside" who would be willing to pay (or force) a mage to transfer their minds out of the fish and into something better...even if they don't have access to their original bodies they could obtain something better than salmon. At that point, you've just got a group of angry people (or angry chimps, or whatever they decide to put their minds into) who want to cause damage to society. They'd probably adopt the same strategies as any modern terrorist style organization. [Answer] **Shutdown the Internet** Well, that is a unlikely action to be performed by salmons because of their lack of sharp whatever, but beside this most to all communication across the oceans is backboned by water-cables. While I still don't think that a salmon might be able to nibble through an intact water cable, at least they could give it a try. If that fails you still could take advantage of the decreased weight of everything in water: go find a big boulder and make it fall at that cable. I assume you do have the power of plot when you will bring your salmons to life, so finding a suitable stone will be no problem. This course of action will be even more devasting today than it would have been some years ago, because optical wires tend to be more rigid than copper wires, which will make them break apart under pressure instead of... morphing (copper is pretty soft). If you do coordinate your efforts you will have america disconnected from europe and asia in no time. And now imagine: no voice-over-ip phone, no clouds, ip routes pointing to unreachable targets... that does have the chance of becoming a very black day for everything that needs internet to work properly. [Answer] # Mass Murder You have a school of fish and a bunch of relaxing humans in the water. How hard would it be to (with a very large school of fish) swarm the individual and force them underwater. Salmon trying to jump up rapids can go fast and far now imagine a school of salmon charging at your face to knock you out or disorient you. Once disoriented they just need to keep swimming into you until your exhausted enough and just drown. Considering that their targets could be young children these criminals could go from beech to beech just murdering anyone who goes out to far or is weak. No swimming hole connected to the ocean would be safe from the murder school. [Answer] Taste great, and incalculably and capriciously be sometimes extremely poisonous (which seems to be dependent on what you eat as a fish in some cases)... [Answer] They could cause mayhem but really messing up the ecosystem. By altering that you cause global damage with localised areas really suffering. Fishing trades and other similar trades will take a huge hit, which could cause a huge spike in the ocean-life population. This all in turn has knock-on effects. Because there are more fish, hunters of fish will come in greater in numbers. If the fish then decided to risk it, they can hang near towns and villages, bringing the hunters into towns which, depending on the animal brings all sorts of dangers. You could also play the numbers game and try to damage places that humans have interacted with to create a certain gain from them - e.g. damns, hydro plants etc. All in all, attacking the ecosystem to create a huge global knock-on effect would cause huge amounts of mayhem. I think Austrailia's ecosystem is a good one to look at, a single species of snake was introduced post-WW2 and it had a huge effect on their localised system - imagine a sentient fish species that could control multiple species. ]

[Question] [ > > * An interesting setting conducive to telling many stories in? *Go!* > * Well thought out inhabitants in this setting with diverse cultural > backgrounds? *Go!* > * A proper noun for any of it? *Houston, we have a problem....* > > > This is a common problem for me. I can develop a world in every detail (or as little detail as a story demands), but I am usually left with documents full of **<insert name here>** or **<come up with something alien sounding for this>**. These placeholders take the longest time to fill, and what I fill them with is less than satisfying. I will spare you the examples. I will also spare you the output spewed by the never ending list of “random name generator” sites that purport to solve this problem. As I am a monoglot, I do not generally attempt to design languages for other races; all the writing will be in English. It should be assumed I do not have in mind what any particular culture’s language sounds like. What I would like is a technique for developing *consistent-sounding*, *alien-sounding* (or foreign-sounding) names within the context of a (sub)culture. Are there *existing*, *documented* techniques or tools for doing this? Addendum: Perhaps I should also be asking if 'not having in mind what the language sounds like' is an inherent flaw with trying to come up with alien sounding names. [Answer] To not have anything in mind about a particular language is asking a bit much. If the names are to be spoken, and thus based on the sound of the language, you need to know *something* about that. Similarly, for written names, you'd need a minimal idea about the language's building blocks and their composition. This can't be avoided since it is at the heart of asking for consistency. That said, many readers don't mind if you take short-cuts. They'd be satisfied with a small part of the language, just enough to make names and still sound like a credible part of a language. To invent names, you could create a set of similar names like this: 1. Define minimal building blocks (and possibly combination rules) 2. Create random valid combinations 3. Filter the combinations for uniqueness, aesthetics, or other reasons for suitability I'll call the building blocks *elements*, since it would be constraining to make assumptions about their complexity. They could be letters, sounds, syllables, or even whole words; either works but produces a different kind of similarity between the names. That's already better than nothing. Personally, I'd season it with a little meaning, to create an illusion of depth: * Sketch a cultural background * Select some combinations and give them a *concept* or an *association*. When naming, use or exclude these situationally. * Create semantics for the usage of any meaningful components you defined (e.g. placement rules for titles, honorifics, adjectives) Let's do a little example. I call my culture the *Ahl*, since one-syllable names are cool and I'm too lazy to go down the alphabet. ## Building blocks and their combination To give the words structure, I invent two types of elements to build words from: $a$ and $b$. For this example, they're combinable by the formal grammar $S \rightarrow aS; S \rightarrow ab$. (So valid words would be structured $ab$, $aab$, $aaab$, and so on.) *This is not a general solution, but a set of rules specific to the culture we're creating names for.* Since "Ahl" should be a valid name, let's say that "Ah" would be a possible $a$ and "L" a possible $b$. We need a few more, so here goes! ``` let aList = ["Ah"; "Riu"; "Ne"; "Iya"] let bList = ["L"; "N"; "D"; "Sh"] ``` *Feel free to ignore the syntax unless you want to computer-generate names in the next step.* Of course, actual lists of elements should be larger. It might take a bit to come up with *good* elements -- these are just me typing in anything that first came to mind. *I am limiting myself to the Latin alphabet and common sounds here. That is, of course, not necessary. When using alien names, you often need annotations on how to read them anyway.* ## Combining Now, just combine them and have a look! Easy to do by hand... but this is Stackexchange, so let's add a program to output all allowed words of a given count of elements. But feel free to do it by hand instead. (The following is in F#. You can paste it, together with the element lists, on the website tryfsharp.org if it works on your browser, or any F# compiler or console.) ``` let aStep = List.collect (fun (s : string) -> [for a in aList -> a + s.ToLower()]) let rec allNames length = if length > 1 then aStep <| allNames (length - 1) else bList ``` `allNames 2 |> List.iter (printfn "%s")` outputs all two-element names (scroll up in the output if you test it on tryfsharp): > > Ahl Riul Nel Iyal Ahn Riun Nen Iyan Ahd Riud Ned Iyad Ahsh Riush Nesh Iyash > > > For three elements, we get a longer list, with names like "Riunen", "Neriud", or "Iyanel". If the rules and elements are chosen carelessly, many combinations will be unusable, but that's not a problem as long as you can find enough usable ones. The count of possible names increases rapidly when using larger element sets, shorter elements, or longer words. Choosing a large set of possibilities adds some realism, but might make the similarity of the names less apparent. You can use much more restrictive rules for making names than would be reasonable to make words of a language. (Seeing how similar names in some cultures are, this is quite realistic.) ## Meaning We need context before adding meaning, so I'll make up something. The Ahl are a mysterious society. Their cities are shrouded in thick fog; they have excellent hearing and can navigate by sound. In their view, strength is knowledge about one another: deception is defense and surveillance is offense, the cautious is wise and the noisy a fool and a nuisance. Someone important in Ahl society would be a *keeper of secrets* or something along that line. So I just take one of the short combinations to create a title for that: *Nesh*. A Nesh is the one who decides what can and can't be told to outsiders. Similar picks can be made for other important concepts: noisiness, listening, knowing, cartography -- things an Ahl might have a special word or phrase for. ## Scaling the effort This method can be used in a very simple way, say, by writing down a dozen syllables and combining them arbitrarily. Spending a little more time, one can think of a few rules on how to build words and how to use them. It should be easy to create names that are distinct from the names of other cultures in the same setting. The difficulty lies in making the names credible as something alien, not something an author just came up with on a whim. There is, of course, much more to this; a major problem lies in sounds and phonetics. It is very unlikely that an alien language can be transcribed into an English text without an elaborate explanation how to read it. But that is a broad topic and this post is already too long. *Also, I'd have to ask Nesh Ryunen if I may disclose any more.* --- ## Addendum: fast step 1-2 via sample text Markov chain In [this answer](https://worldbuilding.stackexchange.com/a/3579/2615), evandentremont suggested a fast way for the first two steps if you have a sample for which you want to generate similar-sounding text. In a first step, calculate the probability for letters depending on the previous letter(s). Then, output random strings that follow the same distribution. (This is a Markov chain approach.) [Here is an F# program to do this with selectable amount of considered characters per character placed (order).](http://fssnip.net/ol) An order of one produces results of limited quality, since the actual sounds comprising words are more than single letters. higher orders require longer samples to work well, but the output looks more sane. This method has its downsides, as you aren't consciously creating the sounds and words. This makes it harder to interpret meaningful patterns into them and design distinct alien features. It is still fun to do and a *very fast* method. Here is what it does for an order of two: **Input**: "lololololol zomg roflmao" > > zomg zomg zomg roflmao lol lololololololol zomg lolol > > > *Wow, it can speak online kiddie* Note that samples in real use cases should be *much* longer. Let's test it with an input that is a little closer to a realistic use case. **Input**: 70 names of planets and moons in our solar system > > Lysida Calia Cara Epinopa Amassa Aritanus Laranus Kalyke Chaliel Tethea Theus Porax Elasiphalia > > > These sound pretty real, don't they? This may be more of a language analysis tool than a language creation tool, but it sure is a quick way to enlarge a set of fantasy names. [Answer] The easiest way to do this is just to pick a sound or a theme for each culture/race/etc and then use that. Some examples: **Clicks** Alien insectoid race communicates using clicks, so their words tend to be very harsh and certain sounds they just don't use. For example letters that use the lips and tongue a lot like m, n, f, g, h might be gone but there would be a lot of k, x, t, and similar letters. The resulting names tend to be things like Kixstex, Takxas, Vakt, Gatrex **Hisses** A snake like race might tend to use long syllabic words and favor hissing sounds. Sourassan, Moarasseen, Hashouss, veehamon **Meaning** A lot of place names in English actually have meaning. Many of these are obvious such as "ford" or "bridge" in a name (i.e. Watford, Cambridge) but others had old-english meanings. For example "ton", "by", and other sounds at the end of a name actually meant something. So you can pick a few sounds that mean something for these aliens and then end all place names with one of those sounds. **Other sounds** Perhaps they use something like a click or a stop in the word, Tr'lk, Ptr!nk, etc. You need to be careful doing this though as readers may well not know how to sound out the word if it's written like that. [Answer] One partial technique is to create an [*a posteriori*](http://en.wikipedia.org/wiki/A_posteriori_(languages)) language - that is, to base it off an existing language. [Here](http://www.languageconnections.com/wp1/languages-of-middle-earth/), J. R. R. Tolkien is quoted explaining how he was inspired to create some of his languages: * **Elvish:** > > But it was his discovery of the Finnish language that truely inspired him. Tolkien wrote about it many years later: “It was like discovering a complete wine-cellar filled with bottles of an amazing wine of a kind and flavor never tasted before. It quite intoxicated me.” > > > “The ingredients in Quenya are various, but worked out into a self-consistent character not precisely like any language that I know. Finnish, which I came across when I first begun to construct a ‘mythology’ was a dominant influence, but that has been much reduced [now in late Quenya]. It survives in some features: such as the absence of any consonant combinations initially, the absence of the voiced stops b, d, g (except in mb, nd, ng, ld, rd, which are favoured) and the fondness for the ending -inen, -ainen, -oinen, also in some points of grammar, such as the inflexional endings -sse (rest at or in), -nna (movement to, towards), and -llo (movement from); the personal possessives are also expressed by suffixes; there is no gender.” > > > * **Dwarvish:** > > Tolkien based Dwarvish on the Semitic languages, due to his observation of similarities between Dwarves and Jews: both were “at once natives and aliens in their habitations, speaking the languages of the country, but with an accent due to their own private tongue…”. Tolkien also commented of the Dwarves that “their words are Semitic obviously, constructed to be Semitic.” Like the Semitic languages, Khuzdul has triconsonantal roots: kh-z-d, b-n-d, z-g-l. Other similarities to Hebrew in phonology and morphology have been observed. > > > * **Languages of Men:** > > Taliska, based on the Gothic language, was an early interest of Tolkien. > > > Soval Pharë, also known as “Common Speech” or Westron in English, comes closest to being a lingua franca in Middle-earth particularly during the time period of The Lord of the Rings. > > > Other less developed languages included: Dalish (derived from Old Norse), and Rohirric (derived from Anglo-Saxon), Rhovanion (derived from Gothic), as well as Haladin, Dunlendish, Drûg, Haradrim, and Easterling. > > > --- Another method is to find a set of letters - may it be a dipthong, a few consonants, or just a random combination - and use it in different names, possibly as a prefix or suffix. Again, drawing on [Tolkien's work](http://en.wikipedia.org/wiki/Category:The_Lord_of_the_Rings_characters): * Theoded and Theodred * Eowyn and Eomer * Faramir and Boromir * Aragorn and Arathorn * Hobbits in general (see the family trees in the appendices of the books); a good example is [the Baggins family](http://tolkiengateway.net/wiki/Baggins_Family), with Balbo, Bungo, Biblo, Belba, Bodo, Bingo, etc. - though I just picked ones beginning with "B". Need I mention [the dwarfs](http://en.wikipedia.org/wiki/List_of_The_Hobbit_characters#Thorin.27s_Company) (Balin and Dwalin, Fili and Kili, Bifur, Bofur and Bombur, Oin and Gloin, Ori, Nori, and Dori - as well as Thorin, son of Thrain, son of Thror)? By the way, there are many more fantastic examples [here](http://lotr.wikia.com/wiki/List_of_characters). [Answer] ## An Involved Way to develop the aural feel of your language The IPA chart show below describes every sound that the human body uses in verbal languages. Every language uses a subset of these sounds. (Other sounds are possible such as [Mongolian throat singing](https://www.youtube.com/watch?v=qx8hrhBZJ98).) [](https://i.stack.imgur.com/5l6UW.png) There is a newer 2015 revision but I couldn't find a good legible copy. Of this huge set of possible sounds, each language chooses some to use. Below is the English IPA chart. [](https://i.stack.imgur.com/Lxcvx.gif) As you can see there are a great many sounds that English just simply does not use and, if you are targeting an English audience, you shouldn't expect them to pronounce your new names "properly". They may not even be able to hear the difference. Have a look at the [IPA symbols with pronunciations.](http://www.internationalphoneticalphabet.org/ipa-sounds/ipa-chart-with-sounds/) ## Language Feel Development Process Here we go: 1. Look through the [GMU Accent Archive](http://accent.gmu.edu/browse_native.php) where the IPA charts for many many languages can be found. Familiarize yourself with the languages / dialects / accents you are most familiar with. If you find a particularly interesting IPA sound set, go find examples of it on YouTube (or your favorite video site). 2. Take some time to learn what the IPA symbols mean and how they sound. Wikipedia has lots of sound samples for [consonants](https://en.wikipedia.org/wiki/International_Phonetic_Alphabet#Consonants) and [vowels](https://en.wikipedia.org/wiki/International_Phonetic_Alphabet#Vowels). 3. Pick a collection of random consonants, at least 15, at most 25. (But go nuts if you want to) It doesn't yet matter if your target language uses or can even hear those sounds, we'll get to that later. (For example, a [monoglot](https://en.wiktionary.org/wiki/monoglot) English speaker most likely won't be able to tell the difference between a [plosive glottal](https://en.wikipedia.org/wiki/Glottal_stop) and a [fricative glottal](https://en.wikipedia.org/wiki/Voiceless_glottal_fricative). Right now, we don't care.) 4. Choose some vowels, probably no more than 12 but no fewer than 5. 5. Decide on a few rules about which sounds can or can't follow other sounds. For example, maybe you want a really fast sounding language, so have a rule that says consonants must come in threes with no intervening vowels. Or, each consonant must be followed by a vowel and vowels are never allowed to start a word. Go as crazy as you want but remember that you will need to rein in any craziness here when you get to the transliteration step. Don't make yourself work any harder than you have to....unless you really want to. 6. Create some candidate word examples using the symbols you've come up with. If the randomness is weak with you, assign each symbol a number then choose a random integer from [Random.org](https://www.random.org/integers/). Sometimes the resulting words won't make sense, such as if you get 5 consonants next to each other (unless you're Czech, in which case, go for it!). Use your good judgement here. 7. Evaluate the emotional feel of your words. Note that every culture places an emotional value on a particular kind of sound. I'm sure you can think of a language that always sounds angry (to you) for no other reason than the sounds of that language, even if the speaker isn't angry. This step is highly dependent on your needs and the needs of your audience. 8. If you're happy with your sound set, go ahead to the transliteration stage. If not, go back to step 3 then refine your sound set or choose new random names. So we have the sounds and a few words, but they are in a language that are probably only pronounceable by you. Let's fix that with a little transliteration: 1. Map each of your chosen symbols to the sounds that closely match your target language. There may not be any close relationship, so you'll need to approximate and get close. You may lose some vocal nuance such as if, for example, you have to collapse a [voiced](https://en.wikipedia.org/wiki/Voiced_dental_non-sibilant_affricate) and [unvoiced dental fricative](https://en.wikipedia.org/wiki/Voiceless_dental_non-sibilant_affricate) down to just a voiced dental fricative. If this is a problem, go back to step 3 and refine your sound set. 2. Now, take the sounds in your set and assign them to the letters and letter combos of your target language. 3. Translate from your IPA symbol set to your target language for each name you need to generate. 4. By this point, you should have some very unusual sounding names that aren't based on any single Earth culture but have the emotional feel you want. ## Maintaining Pronunciation As you can see, it's incredibly easy to choose a selection of sounds that are completely unpronounceable by your target audience. Don't make that mistake. If your audience can't even say your character's names, they are less likely to talk about them. ## Extended Language Exercises This same process can be used to generate a new language too though that will require generating an entire new set of words. Just start with translating the [ten hundred most common words](http://splasho.com/upgoer5/phpspellcheck/dictionaries/1000.dicin) of [Up-Goer Five](http://splasho.com/upgoer5/). [Answer] You can approach this algorithmically. Look into [Markov Chains](http://en.wikipedia.org/wiki/Markov_chain). I once built a random planet name generator using them. Basically, analyze a body of text for patterns and procedurally generate new words. For example > > This is a sentence. > > > You see that given a `t`, it can be followed by `h` or `e`. `I` can be followed by `s`, or `s`. Starting with a random letter keep the chain going. For example start with `t` and you have a 50:50 chance of `h`, or `e` following it. Start with `I`, and you have a 100% chance of `s` following it. The larger the corpus of text, the better the results. You can (and should) also group letters. The larger the group, the more realistic the words sounds. If the group is too big, it will fail to generate new words. I find two or three usually works best. Now, for sounding alien, find a set of words that have the same 'tone' that you're looking for. For elvish words use a list Lord of The Rings words. For alien, use a list of Star Trek planets. For foreign sounding, just use a book written in that language. Here's an [example written in python](http://alexeymk.com/2012/07/15/weekend-hack--a-markov-baby-name-generator.html) [Answer] Names are **labels** used to identify particular people and places. If you have no interest in linguistics, or the specific characteristics of the aliens' language, then all you need is a convenient way of generating these labels. Each name is a sequence of sub-elements -- basically, syllables. So "Obi-Wan Kenobi" breaks down as OBI WAN KEN OBI. You need to identify some syllables as your building blocks, and string them together. The basic requirements are: * Names should be *pronounceable* to the average reader. If all the aliens are called things like Llanfairpwllgwyngyll, most readers will find it annoying. * Names should not obviously be from our world. An alien called Juanita who comes from the planet Barbados is no good. If you want to get slightly more advanced: * Ideally, names from the same culture should have some elements in common. Certain combinations of sounds are more common in particular languages -- so French names sound different from Japanese ones. * The sub-elements can have their own meanings. This can be as complicated as you like, especially for aliens -- names can identify family relations, place of birth, social rank, stage in life cycle, or notable features/achievements. "Thorgrim the Unruly, son of Hardgrim of the Bear Clan, Earl of Mudtown" is a name which contains a lot of information about who Thorgrim is. Basically, that's all there is to it. Choose your name-elements and combine them as you see fit. A couple of useful links: * There are a number of fantasy name generators on the Internet, such as [this one](http://fantasynamegenerators.com/), which basically automate the name construction process. * [This is an entertaining rant](http://www.xibalba.demon.co.uk/jbr/lingo.html) by a linguistics graduate about everything that is wrong with fictional alien languages. Good luck and happy naming! [Answer] Two quick-and-dirty methods that I have used myself, or have seen used. These are not suitable for conlanging, or any story dealing extensively with concepts of language or communication. They are, however, suitable for monoglots and/or English speakers. (1) **Simple names made up of a small number of consonants**. Repeating certain consonants with regularity emulates the look and feel of a distinct phonology. Certain vowel or vowel combinations, when placed regularly in the same part of a word, also create a sense of regularity. Choose four or five of your favorite consonants and make sure that at least one of them appears in each name you create. If you're a fan of the *Avatar*-verse, think of the water tribes' names, almost all of which contain the letter K. Quick and dirty, as I said. Vowels are only slightly more complicated. Q&D rules like 'lots of names ending in A' or 'lots of double vowels for extended sound' can make a strong impression on a reader. With regards to both vowels and consonants, what makes the strongest impression is that which seems least familiar. If you are writing with an Anglophone audience in mind, hard consonants like K and Q create a feeling of alienness, as does liberally sprinkling the least-common tiles in Scrabble. (2) An even simpler (but dirtier) trick is to generate **a series of prefixes and a series of suffixes**, and mix and match them as appropriate. This is actually a pretty common way of generating new names IRL, and not just in the last century, either. You can populate your lists with morphemes taken from rare or archaic names, or take common morphemes and swap out one consonant for a similar-sounding one, such as N for M. This can create names that are vaguely familiar, but not on a 'my next-door neighbor' level. Don'ts: avoid apostrophes, diacritics that you're not sure how to pronounce, ligature letters that you're not sure how to pronounce, and capital letters in the middle of names. These are also quick and dirty tricks, but they lack the versimilitude of the others and tend to stick out like a sore thumb. [Answer] I am going to take a simpler route than some of the other answers here, though I have an insane amount of respect for the linguistically talented out there that really get into the sounds and sound combinations that create names. Something that I have noticed, is that if you go back far enough, most names have literal meanings. So most of my names do the same. Here is more or less the system I use. 1. Pick a language or a group of languages you would like to base your names on. I usually choose a language for each area or culture so that my names have some kind of similarity. I have used Spanish, Latin, Greek, German, and other western languages. (I have little experience with eastern languages, but have been dabbling a bit recently). 2. Find a name or attribute for the character, place, or thing to be named. For example, I chose my name, "Logan", for a character. For a country I chose "hard-lands" and chose "longbow" for the name of an ocean bay there. 3. Find suitable words that match the name in your previously chosen language(s). I discovered Logan meant "small hill" in gaelic. I then looked these up in Latin: "parvus" means small and "tumulus" means hill. For the hard-lands and longbow bay I went with Spanish. Some translations for hard are "arduo" and "dificil". Bow translates to "arco". 4. Modify the foreign words until you think they fit. I left my characters name as "Parvus Tumulus", the great paladin. Latin suited him well, and I didn't feel like I needed to change it. My country became "Arduin" and the bay became "Aargol Bay". I find that if I modify the words enough they make pretty good names most of the time. If not, I'll try other languages or synonyms.I've also created my own language before and named things in that language, but with my limited linguistic skills they were not quite as good as this method. [Answer] The one noticeable mistake authors sometimes make is that groups of names will be too obviously related, too samey. If everyone's called Vunar, Logor, Zenil, Wozan, Terat etc., it's the vocabulary equivalent of the cheap cardboard sets on 60s sci-fi shows. Names have history behind them, and except in the most boring cultures, that history will include waves of immigration and war and other things, which you can easily see by just looking at lists of names from different real-world countries. So, if you need a lot of names, use the techniques above to generate languages, but generate more than one, and mix them up occasionally. If my list above included someone called "q,,qxul", that would immediately make a richer world because you're wondering about the story behind it. [Answer] **I'd be inclIned to say, don't try.** Humans all share a common vocal tract architecture. So we can universally hear all the communicative noises made by another human. And yet ... Our mental processing of noises made by other humans into language involves filters developed in early childhood. I have watched film of a man speaking an African "click" language and parsed it as a man speaking a language I did not know with something in the background making clicking noises. It was then pointed out that the clicks were part of the language. Another example is that in English, voice pitch is a side-channel to speech which carries emotional content and question-marks. In Asian tonal languages the pitch is part of the language, and the same syllable has four or more meanings depending on how It is pitched. Few people can ever become fluent in a language from a different language family which they did not experience in their childhood. They don't have the right mental filters and acquiring new ones in later life is far from a universal ability. Now consider nonhuman aliens. There is no common vocal tract. No common brain architecture. Do they speak with sound only? Maybe they have chromatophores on their cheeks. Maybe they use ultrasonic frequencies. Maybe they have specialized appendages and sign, exclusively or in part. We will need translators. Machines, maybe, or highly trained people raised in a hunan-alien mixed society who are bilingual by birthright. How do humans deal with very foreign names? They adopt new ones. Orientals in English universities very often adopt an English name, since nobody here can pronounce their own name correctly. Sometimes the name is a near-translation or a "soundalike". Sometimes irs just thst they like the sound, say, Sonia. In other human societies all names are capable of translation. But some may not be socially acceptable when translated! Others may simply be useless. Ae49245ef3 translates into decimal but would promptly be forgotten. Note also what happens when two people with the same name share a workplace. One or the other will rapidly acquire a nickname or name qualifier to avoid confusion. I'm almost certain that aliens or their translators will use English-human names for talking to English-humans, and vice versa. A name is basically a label to identify an individual. Tell your story with hunan names. If you want to distinguish aliens from humans by name, pick names from a non English name book. Avoid those which do not have an obvious (if wrong) English pronunciation, because someone may want to read your story out loud. If you feel the need, explain somewhere that alien given names and human tongues and brains are not compatible. On a similar note, it annoys.me when someone introduces (say) a pakori with a paragraph describing a not-quite mule, which plays no further significant part in the story. Just call it a mule. Maybe a sentence about its green coat and blue eyes on stalks if you must. (Added) This was all about naming aliens. For humans I would suggest doing what Vernor Vinge does. Assume that certain aspects of certain cultures including names will persist, even light-years and milennia away from Earth. So in *A Deepness in the sky* one group has a strong flavour of Chinese and Vietnamese -sounding names along with English (I've always assumed Trixia is Tricia via Chinese). Another group has many seemingly Dutch names and presumably origins. Frank Herbert did something similar in *Dune* and sequels. By all means invent a few names but don't assume all or most current names will have vanished. [Answer] Great discussion! As a more linguistically inclined reader, I am pretty sensitive to situations where the author clearly didn't try, and I like that people are making an effort here. It takes a surprisingly small amount of text to reveal at least a couple of grammatical rules that readers can pick up on, especially for heavily inflected languages (those with lots of markers for case and tense, e.g.), and even less for phonetic patterns, even if it's a completely fictional language. Maybe work out what parts of speech or concepts you'll need to represent and develop a few basic rules, and then go crazy with an unfamiliar phonetic veneer. You might come up with the meanings you want first (I need a word that will mean "Yellow Town", and later on I need a "yellow-gold dress", so maybe these can have the same adjective? Maybe adjectives need to have a certain sound or prefix?) and build up only the parts of the language you'll definitely need. Or you can come up with a few sounds you like, then assign them meaning (this one is a verb tense marker, that one means the noun "house") and expand outward. If it's completely random or far too simplified your readers will notice, and, as others have pointed out, you want the middle road between too familiar/derivative and ludicrous. So, for instance, if your alien civilization has cities named Brh;oijg and RI'fhi'fj bn, that might work, but if you add much more into the story than that you'll want to make sure it doesn't look like you tripped and faceplanted on your keyboard like I just did to create them. They look different, but they also look silly, so you have to justify their existence. You can use context to show how these are functional words that are transliterated for your reader-- the alien language probably has a fundamentally different writing system-- and are to some extent comprehensible, even if you don't explain their meaning. Perhaps a semicolon represents a sound not found in human languages. ("Can you tell me how to get to, um, Brah OY-jig?" Janet asked doubtfully, looking at the handwritten instructions. The concierge snorted and read the note over her shoulder. "Ha, no! It's VREE-qhooyik." "Vree-KOY-ick?" "Nah, VREE-qhooy-yik, or something like. We humans have to sort of approximate that middle sound with a loogie-hawking noise, sorry. A Qhhhuuuh sound, you know?") Or maybe ";oijg" means whatever the alien equivalent of ferry or bridge would be, a location where people can cross an otherwise impassable geological obstacle, so you can have towns named Brh;oijg and Xata;oijg along the same feature. And you can get fancy: where that river/canyon/noxious thicket crosses a cultural boundary you might have a varied spelling or pronunciation to indicate a dialect shift but not a completely different civilization with its own language: Guris koijik. Even if you don't go that far you can look for patterns in human languages and try to come up with your own variations to make words with a certain feel. English is often tricky because we have strings of consonants in our Germanic words and ridiculous vowel pronunciations. Greek likes long words with extra-long strings of vowels or consonants. French has loads of silent letters and elided sounds. You could drop articles and most personal pronouns like Latin. Asian languages use tone to indicate word meaning in a way that English really doesn't, an idea which would be cool to incorporate into a new language but would be very hard to represent in an otherwise-English text. Body language and intonation figure heavily into interpersonal communication and likewise don't show up much in written language, but you could tell your reader that only half the meaning comes from the sounds, and verb tense or sarcasm are all about the movement of the antennae. You don't have to slave over making it completely consistent-- English is a great example of a language where all the rules get violated all the time. Just throw your readers a bone and have SOME patterns that don't insult their intelligence-- avoid having every word end in "ees" without reason, e.g. Syllables that don't helpfully contribute to meaning inevitably get dropped in language evolution. [Answer] Try to use lots of q's without u's after, x's, z's, and other unused letters. Try to use symbols for weird names (Ex. ' Xl√h\*i ' ) and underuse vowels. Try using apostrophes after x's(Ex. ' X'dravl '). However, make them easy to pronounce- don't use ' jfdhvhfdughdi'f9dv89•¥ç•¨hçüfvgidjvid ' as a name.(X'dravl = X + gravel with a d instead of a g). If you want not so weird names, ram lots of consonants together with little vowels, or vice-versa(Ex. ' Klcamt ' or ' Ugaeuys '). DON'T make the name completely out of consonatnts. Use a 3 to 1 ratio. Hope this helps! [Answer] # Use phonemes that are technically unpronounceable... ### ... but use an approximation so that the reader can actually say it As sort of an addendum to [this answer](https://worldbuilding.stackexchange.com/a/40345/46434), take something like 70-85% of the English phonemes, fill in the rest with non-English phonemes and maybe throw in an exotic phoneme or two that humans can't actually pronounce, but can reasonably approximate. An interesting real world example of approximating similar phonemes is the Japanese 'fu' syllable. The consonant is actually pronounced by exhaling with your lips close together rather than with your teeth and lips together, but the two sound similar enough that native English speakers say it their way and the Japanese understand it just fine. This is also part of why the Japanese have difficulty pronouncing the 'v' sound. It's possible the aliens have some different oral anatomy that allows them to speak a rather bizarre consonant which we can only approximate with, say, a bilabial trill (sort of like blowing a raspberry or emulating a motorboat propeller), which might be written as 'bb'. Fortunately for you, they don't also have a proper bilabial trill to make these impossible to distinctly pronounce. (avoiding the equivalent of the R/L problem for the Japanese) You can also use phonemes in weird places that they don't normally appear in English. For instance, the 'ng' sound normally only appears at the end of a syllable, so putting it at the beginning of a syllable instead can be exotic, but still pronounceable. Putting all this together can give you a name like 'ngabbur' (NGA - bboor). It's a little tricky to pronounce properly, but they'll forgive you if you say it more like NYAH-bboor or NAH-ber. After all, you don't get mad at children because they can't quite pronounce your name right. Lastly, don't go crazy with glottal stops. Better yet, avoid them altogether. Apostrophed names are incredibly cliche in fantasy and sci-fi. --- In addition, it's pretty likely that an alien living among humans would adopt an English name much like what the Chinese often do when living in the US since their names are often rather difficult for us to pronounce due to the tonality. ]

[Question] [ I'm trying to come up with characters whose backgrounds allow them to have homes, histories, and skills, but will still enable or encourage them to travel in a typical medieval setting. I've never really liked "Adventurer" as a job, and would like my story to have a kind of unlikely-hero vibe. besides the common "Traveling merchant", what kinds of artisans or professionals in fantasy would have a reason to move around the world (or at least visit other settlements)? First time posting, so let me know what to improve. Thanks! EDIT: When I say traveling, I was thinking someone who spends multiple days/weeks/months away from their place of origin as they go elsewhere for their business, or to gather materials for it. [Answer] Engineers, stone cutters, and masons were some of the widest travelers of the era, moving between castle and cathedral construction sites regularly, often staying for only a single season of work at a given site before moving to another when the local weather stopped work. Boatmen also traveled long distances up and down rivers and canals moving cargoes of coal or grain or any number of other goods. They weren't merchants, though they often worked for merchant houses; they were just a transporter. Knights often traveled the tourney circuit during peace time. While a knight might be too likely a hero for your purposes, his 14 year old squire or the even younger 10-12 year old page travelling with him learning chivalry may work for your purposes. His groom, an older man of low birth charged entirely with the care of his horses, even more so. [Answer] Any craftsman during their [journeyman years](https://en.wikipedia.org/wiki/Journeyman_years). A journeyman is a craftsman who just completed their apprenticeship. There was a custom during the middle ages (especially in the German-speaking area) called the "Walz". Young craftspeople spent three years and one day with traveling to other cities, seeking contact to the locals of the same profession and exchange knowledge and experience in the craft. The purpose was to spread crafting know-how geographically. Some professions practice this tradition to this day. Using a journeyman as your main character has several great storytelling opportunities: * They go to unfamiliar locations with the goal to learn about the local customs. That gives you plenty of opportunities to weave infodumps into conversations and observations without breaking immersion. * They have a reason to interact with many different people. Seeking contact to their peers is literally their motivation. But they also have opportunities to interact with lower-class people (if just to ask for directions) as well as higher-class people (to ask for work). As inexperienced outsiders they might also be of interest to more shady characters, both as victims and as pawns. * They are young adults, so they have plenty of room for character development. [Answer] * **Artist and technical people**: musicians, painters, sculptors, architects, engineers, craftsman. They had to go where somebody willing to pay for their work was present (see Leonardo da Vinci) * **Soldier**: if you are smart you don't fight wars in your backyard, therefore you travel and hope to come back * **Pilgrim**: not strictly a profession, but still taking long time * **Cleric**: again, one had to go where the Order sent him * **Tax man or bureaucrat**: go where the government send you * **Sex worker**: chase the customers and escape the moralists [Answer] Here are a few more professions which might travel during the middle ages... * Clergy * Messengers * Royal Inspectors * Spies posing as any of the above * Criminals posing as any of the above [Answer] Coachmen. Because most people described in other answers will need a ride. From the Assassin's Creed II Animus database: > > Travel in the Renaissance was not the disgusting ordeal it is today. Instead, it was merely terrifying. The countryside was filled with bandits, causing most travellers to move in armed groups called caravans. Anxious voyagers usually sewed valuables and gold into the soles of their shoes or the lining of their jackets. > > > Guides called Vetturini were sometimes hired to help plot the route of the caravans and book rooms at local inns, but those carriers were often working with the bandits, just like travel agents today. > > > [Answer] One missing profession is academic. There were universities in the medieval period- several teaching philosophy, latin and theology and the professors and students would transfer around. [Answer] People associated with the judiciary. Most prominently judges, but of course also their retinue (judges were *important people*, so they would have servants, grooms etc.) and lawyers. In the Middle Ages, lawsuits, whether civil or criminal would be handled by different tribunals. Lesser affairs would be handled by local magistrates, but more important cases would wait for the court to come around. This is where the term "[circuit court](https://en.wikipedia.org/wiki/Circuit_court)" originated, which is still in use in common law systems like the US: > > [King Henry II](https://en.wikipedia.org/wiki/Henry_II_of_England) instituted the custom of having judges ride the circuit each year to hear cases, rather than requiring every citizen to bring their cases to London (see Assize of Clarendon).[2] Thus, the term "circuit court" is derived from the practice of having judges ride around the countryside each year on pre-set paths − circuits − to hear cases. > > > I am almost certain that the same practice prevailed in France and Germany, but can't find a source right now. Especially in the more centralized (and centraliz*ing*) kingdoms, this practice played an important role in standardizing the application of law beyond the immediate environs of the lawgiver. [Answer] How about ambassador? In medieval times there weren't full time ambassadors but rulers did have to select people to send on embassies to other rulers. Thus someone whose normal life style might have been stay at home or wanderer would be sent with a small group on a journey of sometimes hundreds or thousands of miles. And there was missionary. A person would go or be sent as a missionary to some foreign land and become revered as someone who revealed the truth to the people, or instantly martyred for trying to replace the old religion, or be treated somewhere in between, and he might settle down in one spot in the land he was sent to, or else travel hundreds or thousands of miles a year on missionary business. And there was slave. A slave might be enslaved by some method in one country and be transported hundreds or thousands of miles to another country to be sold. Many Muslim countries used foreign slaves as soldiers, so a slave could find himself invading a third country in the service of the ruler who owned him. Slave soldiers often became free and sometimes became lords and even sometimes rulers of a whole country. [Answer] Previous answers have been quite exhaustive, so I'm going to add an esoteric example into the fray! **How about a 'Coney-Catcher?** Sourced from [Wikipedia](https://en.wikipedia.org/wiki/Coney-catching): > > Coney-catching is Elizabethan slang for theft through trickery. It comes from the word "coney" (sometimes spelled conny), meaning a rabbit raised for the table and thus tame. > > > A coney-catcher was a thief or con man. > > > [...] > > > The term was first used in print by Robert Greene in a series of 1592 pamphlets, the titles of which included "The Defence of Conny-catching," in which he argued there were worse crimes to be found among "reputable" people, and "A Disputation betweene a Hee Conny-catcher and a Shee Conny-catcher." > > > Since the term originates in medieval England, your 'rogue' character can equivocate or reject the term 'Coney-Catcher' if you wish as it is a new term at that time. Alternatively, you might embrace that word and its meaning entirely. It is around this time the idiom of buying 'a pig in a poke' materialises; selling a dead cat in a sack and claiming it is a pig is a classic 'Coney-Catcher' con. Greene gives other examples in his pamphlets, providing you with plenty of historically accurate (albeit sensationalised) material to develop. [Answer] One more: minstrel, entertainer. Sorry if I missed someone else saying it. And a maybe: I wouldn’t call myself an adventurer, but I retired, sold my house, and have been roaming since. [Answer] **Monks** had a number of reasons that they might travel regularly and potentially for extended periods. From *The Time Traveler's Guide to Medieval England* by Ian Mortimer: > > ...If monks have withdrawn from the world to live lives of contemplation and prayer, how come you meet so many of them outside their cloisters, journeying around the country? The answer is monastic business. Abbots and priors need to attend meetings of their Order, and many abbots and a couple of priors are summoned to attend Parliament. Some traveling is undertaken by other monks to acquire things-including manuscripts to copy for the monastic-library-or to exchange news. But the vast bulk of monastic business is to oversee the abbey's estates. The monk in Chaucer's "Sea Captain's Tale" is allowed by his abbot to roam where he wants on the pretext of inspecting the monastic granges. Some monasteries have a great number of these, with vast estates all over the south of England. > > > [Answer] Everyone else has listed most of the major ideas so far, assuming you didn't want to get into chicanery like [**alchemists**](https://en.wikipedia.org/wiki/Alchemy#Medieval_Europe) or ethnic answers like the **Jews**, **Armenians**, [**Romany**](https://en.wikipedia.org/wiki/Romani_people), or [**Hakka**](https://en.wikipedia.org/wiki/Hakka_people), but something important no one seems to have touched on yet: **If you're actually keeping this historically plausible**? # *Everyone* hated vagabonds. If your travelers *aren't* part of a knight or noble's entourage, **it doesn't matter what your excuse for them is**. The default setting for everyone around the migrant poor is going to be to *assume* they're actually shiftless **vagabonds** and troublemakers. Maybe they're actually pilgrims but, if they're not sleeping in the church, the local boys are going to go beat the hell out of them to get them on to the next town. [Outside of China](https://en.wikipedia.org/wiki/Liu_Pengli), there's not much on [serial killers before the High Middle Ages](https://en.wikipedia.org/wiki/List_of_serial_killers_before_1900) but people certainly understood thievery, seduction and [abandonment](https://en.wikipedia.org/wiki/Child_abandonment#History), rape, and idleness. Freeholders should be farming and [anyone below the freeholders should *really* be farming](https://en.wikipedia.org/wiki/Serfdom) and are possibly [up for grabs for enslavement in backwards areas like England and Russia](https://en.wikipedia.org/wiki/Slavery_in_medieval_Europe). The police system of the era was group responsibility within a clan or village ([one version of which was the frankenpledge](https://en.wikipedia.org/wiki/Frankpledge)) and someone wandering off from theirs couldn't be held accountable... or trusted. Now, having said that, # there weren't any *laws* on the books in Europe until after the Black Death, [when the gutted workforce meant idlers were branded and/or whipped when found](https://en.wikipedia.org/wiki/Vagrancy). High Fantasy tends to stick with the High Middle Ages in the era just before this. That still doesn't mean you should let your characters have it easy, though. There will be the innocent, the kindhearted, and the clergy but the default will be for most to see them the way Eastern Europeans see the “gypsies” and for local nobles to see them as free labor. If that's not something you're interested in going into, they should look rich or like they're part of some rich guy's entourage. People were more forgiving of the religious—and some would dearly love [mendicant friars](https://en.wikipedia.org/wiki/Mendicant_orders) who hew closer to the model of Jesus than the noble clergy—but they saw plenty of hostility too, when they weren't simply being robbed. [Answer] **Ronin.** [](https://i.stack.imgur.com/joGlL.jpg) <https://www.deviantart.com/maxromanchak/art/Lone-Wolf-And-Cub-284013200> Medieval Europe is pretty well covered in previous answers. For a few more ideas consult [Canterbury Tales](https://en.wikipedia.org/wiki/The_Canterbury_Tales) which features characters from less well known medieval professions like Summoner and Pardoner. Ronin is from medieval Japan. <https://en.wikipedia.org/wiki/R%C5%8Dnin> A rōnin (浪人, "drifter" or "wanderer") was a samurai without a lord or master during the feudal period (1185–1868) of Japan. A samurai became masterless from the death or fall of his master, or after the loss of his master's favor or privilege. Ronin are well suited for protagonists - formidable, desperate, adrift and honorless. Depicted: Lone Wolf and Cub, from a sweet series featuring a ronin samurai and his son. [Answer] Some additional professions, that came to my mind: * Mercenary * Assassin or hitman * nomadic cultural entertainer (Showmen maybe like the Edema Ruh in the Kingkiller Chronicles) * Tinker * Taxman (if you want your character to be unpopular) * a bit unusual at that time but maybe interesting: historian, archaeologist [like Ciriaco de' Pizzicolli](https://en.wikipedia.org/wiki/Ciriaco_de%27_Pizzicolli) or cartographer Remember, that you can combine several professions. [Answer] Couriers travelled between ruling municipalities to carry messages to both rulers and common-folk. [Signed, Sealed, Delivered: How Messages were sent in the Middle Ages](http://www.medievalists.net/2014/05/signed-sealed-delivered/) A courier could be anyone from a serf to clergy to soldier to nobility. This gives a wide range of options for character assignment. These couriers would also be good candidates for intelligence gathering. [Answer] There were the pot mender, scissor and knife sharpeners and pot tinner who would make rounds. These were often called **Tinkers** they would also have all sorts of arcane skills and tools that an unlikely hero could make use of. Another class who moved were the servants of all of the others who had due cause the move. Seasonal workers would follow the crops and pick, harvest or thresh the produce as it became ripe. In sheep country you would have travelling sheep shearers. Obviously the witch burners and other institutionalised religious people would try to get all over. [Answer] Entertainers, missionaries, other clergy, taxmen, soldiers - even blacksmiths, shoemakers, clothes makers, midwifes.. Some of these apply to more rural areas where the people would not have had access to someone to make them shoes for example. Some of these professions were basically beggar status at times though. And some of these professions lasted as journeying professions for well into the late 19th century and beyond in more rural settings. Those with such a profession that was valued(like blacksmiths) could barter for shelter and raw materials just by their skills but clients who were wealthy enough to pay for such might live a months journey away from the nearest settlement. This is, in the more rural parts of the medieval world. [Answer] These answers are great. I'll expand a little-- **Surveyor/Tax Assessor** From the *Anglo-Saxon Chronicle*: > > Then, at the midwinter [1085], was the king in Gloucester with his > council ... . After this had the king a large meeting, and very deep > consultation with his council, about this land; how it was occupied, > and by what sort of men. Then sent he his men over all England into > each shire; commissioning them to find out "How many hundreds of hides > were in the shire, what land the king himself had, and what stock upon > the land; or, what dues he ought to have by the year from the shire." > > > Basically, something like the [Domesday book](https://en.wikipedia.org/wiki/Domesday_Book), which is an accounting of English lands, was made up by men the king sent. It was informational (like a census of sorts) but it also served the purpose of giving the King a basis upon which to tax their Lords. Because Lords didn't always self-report so well, it was important to have independent assessors look into the value of the lands, what they could produce, the population, general income and all that jazz. The guys assigned to this ran circuits throughout the Kingdom. Sometimes a lord wanted an assessment/survey of their own land from someone impartial, and they would tap a specialist who wasn't always local but who was recommended by another lord. So it wasn't always a king who was asking. Surveyors were also sometimes called in by circuit judges as experts to solve land disputes. **Church Overseers** What Kings did, so did the church. [The Inquisition](https://en.wikipedia.org/wiki/Inquisition) is an outgrowth of that function, but it wasn't always so hardcore. Rome wanted reports (not necessarily self-reports) on the state of churches and the dogma taught at various parishes. So there were Bishops whose sole purpose was to travel and send word back to Rome. **Builders/Specialist Craftsmen** If you had a specialist craft of any type, be you a stone carver or a maker of armor, or arms, you might not ever get enough business to stay in one place. Once you've made armor for the local lord, who is likely the only one who can afford it, there's no reason for you to stay. It was common for a stone mason or glass worker to move from site to site. **Security and Judges for the Medieval Fairs** I've written about Medieval Fairs in past answers. Basically, there were huge fairs, lasting for weeks at a time where merchants came together to sell their wares. [The Champagne Fairs](https://en.wikipedia.org/wiki/Champagne_fairs) in Medieval France are a great example. At these fairs, they set standards--measurements of length, weight, standards for each industry participating (from cloth to backed goods). Merchants there dealt with the public, but they also made deals with each other. During the course of the fair, any merchant there was subject to the laws specific to THAT FAIR. They set everything from fines for cheating other merchants to a ban for certain practices. It's a really odd thing, because any merchant-type dispute during the fair went to the fair court and the comptroller for that fair--NOT to the regular legal system. What this meant is that there were often a group of people who travelled to help solve disputes and sit in judgement. The Comptrollers were often local and voted for or they could be someone trusted who travels from place to place. Sometimes they were merchants themselves, sometimes they were retired. Often they needed an entourage of people to help them because they couldn't be in two places at once, sort of junior members to sort out the small stuff, or help settle things so it never has to get as high on the ladder as the Comptroller. Security for the fairs was important as well--they would roam about with lanterns protecting the goods and generally being muscle when a dispute got out of hand. They did supplement with local help, but they would often have a trusted group that travelled from place to place. **Literally Anyone in an Entourage for Nobility** Nobility, from knights on up, liked to travel--for sport, for politics, and they brought a TON of people with them. The higher up you were the more likely you were to bring a whole dang staff with you. Almost every profession you can think of that a noble might want. A horseman, a houndskeeper, a specialist tracker, falconers, squires, messengers that you sent ahead to let another noble household (or your country house) you were a few days away, people to maintain carts, a cook for the road...if you can think of a purpose, there was a job in it. **Transporters of Goods and People + Guides** Hired out by merchants and nobility, there were people who simply traveled to get stuff or people from point a to point b. Many times by water, but not always. There were also road guides for tourism, especially pilgrimages. These were not generally religious figures. They knew where to stop for lodging, which wasn't always apparent, because in early Medieval times, this wasn't always an inn. See my answer here about what [inns were like](https://worldbuilding.stackexchange.com/questions/108346/how-close-were-inns-in-medieval-europe/108356#108356) and how far apart they were. A road guide knows who should be bribed and who should be ignored, they know how to avoid highwaymen, where to stay on a route and so on. They also, like tour guides of today, might get a small kickback from lodgings and services for bringing their group by. **Seasonal Workers** Since the fall happens everywhere at the same time, harvests tended to use mostly local labor. This changed with the labor shortages of the Black Plague. If a lord needed extra labor they generally asked nearby lords for people, so prior to the plague, there wasn't as much mobility for this--that is to say people didn't travel everywhere to do this (there generally wasn't enough time in a season to do so) but might go to one particular place in a group of harvesters from one lord to another. Again, this changed late in the period. **Homing Bird Keeper/Transporter** This is a bit obscure, but as early as 1150 in Bagdad, homing pigeons were used to send messages. This wasn't widespread practice in Medieval times, but in fantasy, you can go all George RR Martin with it. In order to send messages to a place, you have to take the birds AWAY from their home, which means that they have to be cared for on the road, and transported to far away places in a kingdom. So a King or lord that wants other lords to be able to communicate with them, sends a bird transporter all over the country with birds in cages who know their home as the King's castle keep, and they can send a short urgent message to their regent or vassal. And, while you are at their keep, you can take a bird from the king's vassal and bring that back to the king so that the king can send a message to the vassal and so on. Could lead to EXTENSIVE travel...Could be for any lord who just wants a communication network... Doesn't have to be birds as this is fantasy, can be any homing messenger creature. [Answer] [Plague Doctors](https://en.wikipedia.org/wiki/Plague_doctor) > > In times of epidemics, such physicians were specifically hired by towns where the plague had taken hold. > > > [Answer] A quick scan of answers so far misses the traders: * England sold wool by the boatload to Europe. Towns had annual fairs for trading. In fiction this is used to good effect in Ellis Peter's tales of Brother Cadfael, a Welsh soldier/crusader turned monk. It's also used in Ken Folletts "Pillars of the Earth" series. * Google "Hanseatic League" * Pepper was extremely valuable in the middle ages. Pepper and cloves. It came overland in several stages. * Google Silk Road -- trading from Asia Minor to China. Your character can be either a trader, or in a trader's employ. (Being a general trouble shooter as in Poul Anderson's tales of the Solar Spice and Liquor Company.) [Answer] In much of Late Antiquity (which was very much like the Medieval era, more so than earlier Antiquity in many ways), the Western Roman Emperor's entire court was mobile and travelled the Empire. So clerks, court officials, servants, and sundry hangers-on. ]

[Question] [ Suppose we detect a stellar black hole passing near the Solar system, and we have technology and time to send a manned mission to study it. Are there any experiments or observations that would help us learn more, maybe test some of our theories or the whole mission is pointless? I would like to use this as a setting, if it makes any sense. **Envisioned Story** My "hero" is a physicist suffering from some kind of incurable disease, that won't prevent him from doing his mission. He knows it's a one way trip and that's why he volunteered to be send there. My plan was to do some observations, experiments with probes, and finally enter the black hole. I know it's a cliche but it feels cool. [Answer] # What could be learned? There are so many things you could study by looking at a black hole. There are lots of open or partially unsolved problems that surround them: * **Does [Hawking radiation](https://en.wikipedia.org/wiki/Hawking_radiation) exist?** While it has been predicted theoretically, direct evidence is lacking - well, nonexistent. Stellar-mass black holes aren't the best targets - primordial black holes are better - but you never know. Extreme up-close measurements could yield results. * **How do [astrophysical jets](https://en.wikipedia.org/wiki/Astrophysical_jet) form from accretion disks?** Jets are present around many objects, black holes included (if there is an accretion disk present), but the precise mechanism for their formation is unknown. The prevailing hypothesis is the [Blandford–Znajek process](https://en.wikipedia.org/wiki/Blandford%E2%80%93Znajek_process), but this has yet to be confirmed. * **Is general relativity accurate?** All the evidence is in its favor, but more experiments never hurt. Many [tests of general relativity](https://en.wikipedia.org/wiki/Tests_of_general_relativity) could be repeated near the black hole, where relativistic effects are extremely strong. The tests could include + **[Gravitational lensing](https://en.wikipedia.org/wiki/Gravitational_lens)**, the bending of light by a massive object. + **[Gravitational redshift](https://en.wikipedia.org/wiki/Gravitational_redshift)**, the change in wavelength/frequency of light near a massive object. + **[Frame-dragging](https://en.wikipedia.org/wiki/Frame-dragging)**, which is important near rotating massive objects.We could also test [alternative theories of gravity](https://en.wikipedia.org/wiki/Alternatives_to_general_relativity), and maybe rule some of them out. * **Do black holes even exist?** While there is quite a lot of evidence for black holes or black-hole-like objects, alternatives or modifications have been proposed, including + [Eternally collapsing objects](https://en.wikipedia.org/wiki/Eternally_collapsing_object) + [Magnetospheric eternally collapsing objects](https://en.wikipedia.org/wiki/Magnetospheric_eternally_collapsing_object) + [Black stars](https://en.wikipedia.org/wiki/Black_star_(semiclassical_gravity)) + [Fuzzballs](https://en.wikipedia.org/wiki/Fuzzball_(string_theory)) + [Dark energy stars](https://en.wikipedia.org/wiki/Dark-energy_star) + [Gravastars](https://en.wikipedia.org/wiki/Gravastar)Many of these ideas are wild, and some cannot be tested by observations of black holes (or "black-hole-like objects"). * **Is [information lost](https://en.wikipedia.org/wiki/Black_hole_information_paradox) inside black holes?** The black hole information paradox - a notable problem in general relativity, quantum mechanics, and physics in general - asks whether or not "information" about physical states is lost inside a black hole. This has implications regarding [string theory](https://physics.stackexchange.com/a/3177/56299), among other areas. * **Do [naked singularities](https://en.wikipedia.org/wiki/Naked_singularity) exist?** The [cosmic censorship hypothesis](https://en.wikipedia.org/wiki/Cosmic_censorship_hypothesis) states that they don't; observing a rotating ([Kerr](https://en.wikipedia.org/wiki/Kerr_metric)) black hole could give us more information about this. Gravastars also provide a solution to the paradox; if black holes are actually gravastars, then the paradox could be solved. Whether or not [the two are observationally different](https://physics.stackexchange.com/q/87472/56299) is a harder question. # Why send humans? Now, all of this could be done by computers, not humans. So why send humans, who need that pesky air, food, water, waste disposal, life support systems, life insurance, etc.? Good question. Here are my answers: * **It's good publicity.** Would you rather be the first nation/company to send a probe to a black hole, or the first nation/company to send brave, daring human explorers out into the great beyond, champions of our species - to boldly go where no man has gone before? Admit it; the second sounds a lot better. Yes, the astronauts will have to deal with a lot of risk. But there are going to be plenty of people willing to do it. * **Communication is hard, and humans can make on-the-spot decisions.** Light travels at a finite speed, and on astronomical scales, this is pesky. It takes 8 minutes for light to travel to Earth from the Sun (one astronomical unit, or AU). The Solar System is a *lot* larger - even Neptune is 30 AU away from the Sun. This black hole is likely farther, especially if it's going to cause no disruption to the system (unlikely, unless it's *really* far away). Therefore, you can either pre-program the itinerary beforehand, or send people who can make on-the-spot decisions. Mission Control isn't going to be there to hand-hold the ship's computers through this thing, and humans do have a certain knack for solving problems when things don't go as planned. [Answer] ## There is no point in sending a manned mission! As @HDE22686 noted, there *are* many interesting phenomena associated with black holes. Given the opportunity to study one up close, it is likely that missions *will* be sent. However, describing all the cool phenomena associated with black holes only means they will be studied - **not that humans will be there to see them** ## So why on Earth would you send a human to a black hole? * **Human error influences data**: This is a once-in-a species (potentially) chance. There is no point sending humans capable of error on board this probe when a *considerable amount of money* is at stake. * **Black holes are deadly**: Any miscalculation in the trajectory of the probe may risk ending human lives, millions of miles away from home - is that really worth it? Additionally, exotic radiation is associated with black holes. It's safest not to play with that. * **We can send other organisms instead**: If the point is seeing the effects black holes have on living tissue, why not send rats? Or dogs? Or chimpanzees? Or a sample of human flesh kept alive by life support? * **Multiple unmanned probes decrease chances of inaccuracy**: While machines *are* capable of failure - see the [*recently crashed Mars rover which was brought down by a glitch*](http://www.news.com.au/technology/science/space/europes-mars-lander-failure-caused-by-glitch-but-gives-researchers-valuable-lesson/news-story/a2db7c2f2c470ffe31117c6ec24868eb) - many agencies capable of sending probes *will do so*, meaning data collected will generally reflect the truth. Compare this to multiple probes with humans on board. * **Missions are flybys**: When we send spacecraft out of the solar system to observe distant objects, we never intend to get them back - and even if we wanted to, it's extremely expensive! The first few generations of Mars colonists will be stuck on Mars forever because we aren't willing to pay for ships capable of escaping Mars after landing. With that in mind, why would we send people out of the Solar System and then attempt to get them back? * **Machines are competent and won't need to make major decisions**: While humans *can* make on-the-spot decisions, a probe with basic sensors, locomotion, and apparatus is capable of steering itself. No situation will arise where *only* a human could decide what to do. **In conclusion,** we'll be killing people - who could mess up the missions - in strange and potentially cruel ways, millions of miles away from home, with no chance of retrieval - **when machines can do the job even better.** Missions? Yes! People? *No*. [Answer] # For science! At present we have two main theories of physics: * General relativity, which is about very heavy things and gravity. * Quantum mechanics, which is about very small things. We have not been able to fit these two together. One of the reasons for this is that we have not been able do experiments that test both at once. Objects that are small enough to have quantum effects are not noticeably affected by gravity. At least not strongly enough that we can distinguish between different theories of gravity. Our other theories (eg. electromagnetism) can be fit with one or the other, but not both at once. Black holes changes things. Here gravity is very strong and even electrons will feel the pull. If we would be able to bring along both a neutrino source and a neutrino detector, we would learn much about these mysterious particles. However, at current or near-future tech levels neutrino detectors are *very* massive and not something you can move off-Earth. Even without that I am sure there are numerous experiments we could do with a humble electron ray that will be very useful. The main experiment I see done is sending a laser or a ray of electrons in very close to the event horizon, and putting a detector where it comes out. Useful results would be angle of deflection and time taken for the journey. Maybe also how spread out the beam has become. If the hole is rotating, sending beams both with and against the rotation will be interesting. # Why humans? This is about science, which means we won't know in advance what experiments we want to perform. Results of the one experiment will suggest new physics theories. These will suggest new experiments to perform. A machine cannot do this. (Unless you have powerful AI) If there are no humans on the spot, the results will have to be sent to Earth and new commands sent back. This will take too much time and the black hole will move away before we are done. I suggest a crew consisting of a mixture of astronauts and physicists. Both will need to have a good understanding of the other side, but in the end they are different in their goals. The astronauts will want to keep everybody alive and return home in one piece. The physicists will want to perform more experiments. *More*! **MORE**!! Other answers have suggested sending several unmanned probes instead of a manned one. I suggest a manned ship carrying many unmanned probes. The ship stays prudently far away from the radiation, the probes go closer, not close enough for tidal effects to destroy them, but definitely into hard radiation areas. # Parting gift. The time comes when the hole moves away and we have to go home to Earth. Leave something behind for aliens to discover, maybe something like the Pioneer Plaques and Voyager Golden Discs. The hole will be a scientist magnet from every civilization it passes nearby and a good meeting spot. Maybe we will find an alien artifact already there... [Answer] Don't send humans! There are two basic reasons to send humans to space: 1) To cope with the unexpected. When your mission goes off the rails it's much more likely to succeed if you have a very flexible system on board: a human. Think of Apollo 11, coming down into the rock garden. The tech of the time would have crashed the rocket, even modern tech would be hard pressed to land it safely. A human pilot was capable of analyzing the problem and dealing with it, thus saving the mission. 2) When there is an analysis problem that can't reasonably be handled by tech. Apollo era tech couldn't do a reasonable job of gathering moon rocks. If we wanted to bring home samples other than whatever happened to be right under the scoop we had to send humans. (And note that the landing problem in #1 is also an example of this.) Now, apply these standards to a black hole mission: 1) The unexpected, sure. It's always useful to send a human. However, that means an awful lot of life support equipment, you can send multiple unmanned missions for the price of one manned one. 2) Jobs that need a human. What jobs? There are no samples to go pick up or the like, it's going to be an extremely lethal environment outside the hull. What can the humans do??? Basically nothing! Also, consider that the most interesting observations will be made as low as possible: 1) Delta-v requirements mean that you can get lower if you can burn all your fuel on going down and not save any for coming home. 2) The deeper you go the more dangerous the environment becomes. If you can get close I would **expect** lost probes as there will be lots of fast-moving debris. Note: If the black hole is far enough out you might send a manned mission as a mothership. A lagtime of minutes or hours could be of considerable value over a lag of months from Earth. [Answer] The expense of sending a manned mission vs. many unmanned probes is going to make the latter very enticing. Certainly humans can adapt to situations better, but technology has gotten to the point that most of the situations they could adapt to are unlikely enough to occur that you'd make up for those occurrences by the redundancy of the probes. The other argument for sending people may be to explore/check out something so totally unexpected that we'd have no way of accounting for it in the probe's programming. But - and this may just be the cynic in me - I think that's extremely unlikely. In a far enough future that this is feasible at all (though granted, if we were OK with the probe taking 10000 years to make it, and another 3000 to get the data, we could do it with today's technology!) tech is (hopefully) going to be so cheap and small that it'll be easy enough to make the probes just collect all the data they can. We think there *might* be objects orbiting the black hole, right? So a couple dozen of those probes will be set to divert course and orbit those instead, and collect data from them. I'm going to assume that they all have advanced physics processing units and would be able to calculate those orbits on the fly. And still some of them might crash (or just veer off into the void), but again, you can send a dozen probes for the cost of one manned mission. I could potentially see live humans as ambassadors in the event that extraterrestrial intelligence is met, but the cynic in me doubly doubts that we'll ever find extraterrestrial life, let alone intelligent life. (It believes such exists - the universe is too vast not to - but it's also too vast to feasibly encounter any.) The probes collecting all that data, petabytes upon petabytes of it, will see any evidence for life that might be out there. They won't recognize it, of course, but the human scientists on earth 15000 years later (after receiving a mysterious signal from space that they decode to find that they can decode it perfectly to ancient English, and after consulting historians who kept the records of ancient, quaint technology are able to realize that a forgotten civilization of a bygone era sent it) *might* glean some evidence that there could be some kind of potential for the conditions of life on one of those bodies. But anyway, the probes aren't really there for that. They're gathering all the data they can because it was cheap at the time, but mostly they were looking at the black hole. Some of that information could provide insights to the current civilization, if they can translate it from a language that died thousands of years ago. But then again, 15000 years into the future of this already future point they may have built a miniature black hole and replicated most of the experiments anyway. Honestly, with the time lag, I'm not sure I see the use of even sending unmanned missions. If I were to even do that it'd just be a probe that has "Kilroy was here" spray-painted on it, just for giggles. Sending a manned mission that distance - no matter how dangerous a black hole is - is a death sentence. (Even if they could come back, everyone and everything they've ever known will have been dead for ages.) That is not a problem for the hero in your story, though, and is in fact kind of a selling point. I have a simple proposition for why they'd send a manned mission - **he wants to go**. "I am going to die anyway, but I'd be the only human in all of human history to see a black hole up close." Sounds like motivation enough for me. In my view, he's not able to convince any government's space agency to let him do that, but a private aerospace firm finds the earnestness in his mission and undertakes (...pun intended) the project. He isn't actually necessary to gather or interpret the data, but he's able to make sense of it when his craft reports it to him. He gets to make all those conclusions and realize that he's the first person in history to not only see a black hole up close, but also finally understand Hawking radiation/information loss/general relativity. He passes away to a peaceful death, as the camera zooms out revealing the cartoon of the fellow with the big nose peeking over the wall, spray-painted onto his ship. [Answer] Send Humans! Why? Because of archaeology... As others have stated, computers can handle the mission, running a bunch of experiments and sending us back the results. Those automated experiments are, by definition, limited to studying the expected characteristics of the black hole. They can test for minute variances in established theories and provide detailed measurements of the black hole's physical characteristics. But automated experiments cannot study the unexpected. That black hole may have a solar system of its own, spinning around it in slowly decreasing orbits. The planets of that solar system will vary in origin, having been stolen from different solar systems which the black hole passed through. Studying those planets and their surrounding dust clouds, is our opportunity to sample matter from farther away than we could ever travel. And some of those adopted worlds may even have once harbored intelligent life. [Answer] There's a few pitfalls to trying to study a black hole up close 1. Not much is coming out to study. Mostly black holes emit x-rays. No matter, no light, no nothing. 2. Once, say, a probe goes in, it's not coming back out. Nor is it likely going to be able to send data back past the event horizon. 3. [Time dilation](https://www.youtube.com/watch?v=orx0H9mBeXk). The closer things get to the black hole, the slower they appear in real time. So let's say you sent a team to the black hole. They would return thousands or millions of years later. So whomever sent them would be long gone by the time they got back. [Answer] My favorite scifi author Greg Egan wrote a short story about just this. It's available free online if you're curious: [The Planck Dive](http://gregegan.customer.netspace.net.au/PLANCK/Complete/Planck.html). Quick TLDR: It's set in a very farflung transhuman society, and they do it out of pure scientific curiosity by forking their personalities. As others have said, there's not really any reason to send a person in on a one way trip except for the experience of it. As you say, a sort of elegant way for a scientifically minded person to die. [Answer] ## How to find it? Black holes are by definition invisible the only way to find one is to look around to see stars being blocked out by them. ## How to get data? To get data from a black hole you would have to study the effects on what it does to the surrounding area and **not** the black hole itself. ## Sizes of black holes: A "small" black hole is an instant death due to spaghettification of the human and the probe. **A supermassive black hole's estimated inside view:** [](https://i.stack.imgur.com/F2ggu.gif) A large black hole is a slow death because the event horizon spans much further out where the gravity is still "survivable". This would probably be the most amazing way to die because you would see the universe slowly fading away. On earth maybe 100+ years might pass because of time dilation while for you only 10 minutes might have passed. ## Event horizon: It's very simple: You pass it and there is **no** way to get you or your data out of it. A black hole by is by definition black because it sucks in everything. X-Rays, radio frequency waves, entire stars and also light. This means that once you're in you'll have to play cards with yourself until you and the shuttle disappear from existence. ## Time dilation: [](https://i.stack.imgur.com/BK3cx.jpg) A black hole is so heavy that time itself behaves differently. This is because we dont merely live in space or in time but in spacetime. Spacetime can stretch depending on how "heavy" something is. For example, every 60 years our satellites need to add 1 second to their own clock because on earth time goes a tiny bit slower. This is exactly the same near a black hole as on earth except that it is magnified so much that once you pass the event horizon someone flying outside it would see you falling forever. ## Spaghettification Spaghettification happens when gravity on the close end of an object is higher than the further end. (On earth this would be your feet.) Because a black hole is much more powerful than earth it will stretch you from the closest end to the furthest until you are basically one long string of human. ## Gravitational Lensing [](https://i.stack.imgur.com/Vtp3h.gif) A black hole is so heavy that it will warp the space around it like a magnifying glass. ## Pro's of a human * Amazing view. * Time travel (only future). ## Cons of a human * Bodily harm due to gravity, spaghettification etc. * Can accidently mess up the data. ## Bonus points * Stand near a supermassive black hole to travel into the future (still outside event horizon but close enough to experience the effects) [Answer] There's no point sending someone into a black hole in and of itself, because once they're in they have no way of sending any findings back. However, sending someone *near* a black hole could allow them to study the various features mentioned in other answers. For the purposes of your story, the mission could be one that goes near a black hole to study it, but with no way to prevent the eventual crossing of the event horizon. That part wouldn't be the actual intent of the mission, but an unavoidable end to a mission focused on what could be done prior to that. [Answer] As someone with less of a scientific background as many of the contributors on this question, my gut reaction is that part of the case for humans exploring black holes can be made simply by considering human nature and it's role in history. We are, by nature, adventurous creatures who inevitably grow used to our surroundings and seek to expand our horizons. The fact that we are curious, and want to know more about our surroundings (be they terrestrial or extraterrestrial) suggests to me that, while perhaps millions of years down the road, we will inevitably attempt to explore these phenomena ourselves anyway. Some of the most empowering, inspiring and audacious ventures undertaken by mankind have been marked by certain death/injury/loss, even by those embarking upon them. The promise of our species is that, despite these factors we will always want to explore further. If there are individuals willing and wanting to take that kind of leap, why not allow them to do so, even if only to entertain our nature. (Philosophical-ish response conjectured from an assumption of economic, technological and legal viability of the project) ]

[Question] [ Most settings with a magical component, whether this means wizards, magical races, or something similar, seem to be parked at a medieval level of development in terms of technology and society. Is this just because that's how the "high fantasy" genre developed, or is there some fundamental reason that having magic in a modern/future/high-tech world would be a bad idea? [Answer] One primary reason why this is the case is because settings with more advanced technology and magic mixed together require a great deal of thought about how technology would likely develop when magic exists in the world. If magic exists, it's likely that many things in our world would have developed differently. How we handle long-distance travel, communication (the Internet), the games we play, the jobs that are available, any or all of these things could be changed when magic is introduced. Rather than create an entirely different world that readers will recognize as alien, it's often simpler to revert to more primitive times, and simply add in magic when its existence doesn't require you to create a dozen centuries of magitech. It's a lot of work for the writer, and it may confuse or alienate the reader. Thus, to easily and quickly create a world their readers will recognize, many authors prefer to use the "standard" medieval fantasy setting. [Answer] The genre of "urban fantasy" has been gaining in the last few years, largely related to werewolves and vampires. Yet still, there is a growing interest in having magic in a modern world. On the other hand, these stories also tend to be set in a world where magic is not accepted as being real, and the really wonderful magical world is hidden from the eyes of the general public. Perhaps it is too hard to really decide what the world would be like if wizards walked among us? Magic and futuristic technology is another story, and I think part of it may be that future tech itself seems very magical. Reminds me of Arthur C Clarke's quote: "Any sufficiently advanced technology is indistinguishable from magic." In essence, the magic in fantasy literature and the high technology of science fiction are not all that dissimilar. I can shoot fireballs out of an exquisitely crafted wooden wand, or I can shoot fireballs out of an XK-Red-3015 Magmamatic Disrupto rifle. The only true difference is the explanation behind the ability that people have. Which isn't to say that "magic" doesn't make its own special appearances in other clothes. Yoda's ability to use "the Force" and Gandalf's plethora of spells are also not all that different from each other. Just slightly different dress. Then of course, there's the Shadowrun universe ... a post in and of itself. [Answer] # Magic can lead to modern technology. In the 13th century CE, Robert Grosseteste and Roger Bacon proposed what is recognizable as a modern [scientific method](https://en.wikipedia.org/wiki/Scientific_method#History). They reinterpreted Aristotle in light of ideas and practices presented in works that Arab polymaths had been putting out over the last couple centuries, such as *Book of Optics* by Ibn al-Haytham. In the following century, William of Ockham stated his parsimony principle of choosing the shortest hypothesis that explains the observations. These led over the next few centuries to rapid advances in science (understanding of natural laws) and technology (their application). Fast-forward to the 20th century, when centuries of this progress have dramatically affected life in the real world, and Arthur C. Clarke stated [his famous third law](https://en.wikipedia.org/wiki/Clarke%27s_three_laws): "Any sufficiently advanced technology is indistinguishable from magic." A few years later, a character in the Studio Foglio webcomic *Girl Genius* [stated the corollary](http://www.girlgeniusonline.com/comic.php?date=20081205): "Any sufficiently analyzed magic is indistinguishable from science!" This observation, also attributed to [Larry Niven, Terry Pratchett, and others](https://en.wikipedia.org/wiki/Niven%27s_laws#Niven.27s_Law_.28re:_Clarke.27s_Third_Law.29), is why [answering "what is magic" isn't as easy as it sounds](https://worldbuilding.meta.stackexchange.com/q/56/601). Heck, how do we know that phenomena on which we rely in the real world aren't magic? So if your world develops a scientific method, systematic analysis of magical phenomena as natural laws with a mathematical basis and subsequent application are likely to follow. Consider the [Tippyverse](http://www.giantitp.com/forums/showthread.php?222007-The-Definitive-Guide-to-the-Tippyverse-By-Emperor-Tippy), a thought experiment built on the *Dungeons & Dragons* role-playing game. In the Tippyverse, mages have perfected their understanding of "magical" phenomena to the point where they can [trap spells in push-button devices](http://www.giantitp.com/forums/showthread.php?109791-Create-Food-Trap). These machines act as food dispensers, showers, training dummy makers for grinding experience, emergency rooms, transport, and more, allowing for a way of life much closer to the modern real world. Or in another setting, people might discover how to harness fields associated with ley lines for power instead of discovering fossil fuels. The question for a writer then becomes what would keep philosophers in a setting from arriving at a viable scientific method. One way, as you have seen, is to just set the story before analysis of magic has had a chance to spread. Another way is to make magic not repeatable, such as "wild magic" or magic that relies on summoning demons. A third thing that could hinder the progress of science and useful arts is if survival is difficult enough that there are not enough [surplus resources to devote to science](https://worldbuilding.stackexchange.com/a/517/601). [Answer] [Clarke's three laws](http://en.wikipedia.org/wiki/Clarke%27s_three_laws), 3rd point > > Any sufficiently advanced technology is indistinguishable from magic > > > Medieval societies tend to use more "magic" than modern societies due to the fact that modern society tends to be able to duplicate magical effects, after all, in the past did lighting a fire or using gunpowder not seem as wondrous or as fearful as sorcery? An example science duplicating magic of this is seen in the Nasuverse (Fate/ Series) where [Magecraft](http://typemoon.wikia.com/wiki/Magecraft) is > > the ability to reproduce what can be scientifically realized regardless of time and funds. The limits of Magecraft have changed with time, as science evolved and sorceries from before became technically possible through science. > > > Of course that's not to say Magic in Modern societies can't exist and be more open. In the Nasuverse there are organizations which still work with aspects of Magic (Magecraft) such as the [Mage's Association](http://typemoon.wikia.com/wiki/Mage%27s_Association) based in London, the US Backed Organization mentioned in [Fate/Strange Fake](http://typemoon.wikia.com/wiki/Fate/strange_fake) who duplicated the Fuyuki Holy Grail War Ritual, [Yggdmillennia](http://typemoon.wikia.com/wiki/Yggdmillennia#Yggdmillennia) in Fate/Apocrypha who sought to separate from the Mage's Association and the [Egyptian Atlas Academy](http://typemoon.wikia.com/wiki/Atlas#Atlas), one of many subdivisions who work with the Mage's Association. Though like with the Nasuverse, Magic in Modern Society tends to be hidden away (the Mage's Association does care how inhumane experiments are, they will only act if the existence of Magic is made public), in Anime (particular Magical Girl Genres) those with magic kept their magical identities hidden. There is however some anime which does have Magic in Modern and/or futuristic societies. One notable mention is that of [Mid-Childa](http://nanoha.wikia.com/wiki/Mid-Childa) and the World under governance of the [Time-Space Administration Bureau](http://nanoha.wikia.com/wiki/TSAB). due to scientific advancement, [Magic](http://nanoha.wikia.com/wiki/Magic) is > > closer to science and technology than mysticism > > > and it being used as an alternative to Mass Based technology which is seen as more destructive to nature, while a lot of the characters use melee weapons (swords, hammers, scythes) or Staffs, [Teana Lanster's](http://nanoha.wikia.com/wiki/Teana_Lanster) "device" [Cross Mirage](http://nanoha.wikia.com/wiki/Cross_Mirage) is a set of guns while one of the forms of [Erio Mondial's](http://nanoha.wikia.com/wiki/Erio) device [Strada](http://nanoha.wikia.com/wiki/Strada) obtains rocket thrusters making him like a rocket when he attacks. --- The reason, I believe, that a lot of the time Medieval Society and tech is used over modern or futuristic is that the characters don't know any better as they have nothing to compare to which exists in their world and the audience can believe that. In Star Wars, Han Solo has trouble believing in The Force passing off as just luck because he knows how his ship can achieve speeds faster than light. One of Darth Vader's officers at one stages refers to The Force as an old sorcery which no longer has power (demonstrated otherwise mid sentence) because he is on board a station which can blow up planet. This is because they are in a society in which explains how energy is fired from a weapon or how a city could float in the sky. Yet there is this unexplained power behind firing lighting from one's fingertips or lifting up rocks and ships with one's mind. As such, for Magic to be apart of a more modern society it has to be explained why it can be used? Why can't you just use science or vice versa? How come some people can use it and some can't? Sure some of the audience may not care but there are others who would strive for this and if your making a world/universe which you want audience to be invested in you'd want those people to believe in that world, the closer it is to our world, the harder it is to have the unexplained. With the 2 anime I mentioned * In the Nasuverse, magic is mainly done though [Magic Circuits](http://typemoon.wikia.com/wiki/Magic_Circuit) - a pseudo-nervous system that spreads itself through the human body * In the Nanohaverse, Magic is achievable with the [Linker Core](http://nanoha.wikia.com/wiki/Linker_Core) - an organ in a mage's (knight's) body which works to link and manifest Mana generated within themselves. In medieval times how would we know these things without the technology/techniques available, even if you were to explain it you then have the audience ask "How do they know?". The best worlds have their concepts explained by the world itself and the people therein, not the author (ie. supplementary material released in the form of a research paper that would have been published in the world, similar to how Fate/The Fact was released as a magazine which featured an interview with Rin Tohsaka explaining the Resistance against the Harwey plutocracy), therefore if the people of your world can't explain it then we don't expect them to. Modern societies/tech is easier and require less work to explain things [Answer] It's because the medieval period on historical Earth was the last period when magic was treated as factual. Then the Age of Reason etc. led to science, which eventually (though not immediately) developed understandings of how most things worked, that were in opposition to, or at least absent, magic and spirituality. If magic on Earth had featured more scientifically-observable magical phenomena (such as flashy spells found in fantasy magic systems) then science would have included that magic in its observations. Since this is what happened historically, making a fictional reality where magic coexists with higher technology, probably implies a different history, society, economy, politics, associations, etc. Back to the real world, some science is starting to take more notice and interest in some phenomena once considered magic/spiritual. I imagine that in future centuries, if we survive the effects of our own industrialization, there may be more integration of technology with "magic". [Answer] In my opinion, magic can lead to its very own kind of technology, possibly very similar to ours. If it is a kind of magic where you use one energy source to trigger one other event (like in *The Kingkiller Chronicle* by Patrick Rothfuss), then it actually is very similar to **electricity** and you can imagine a watermill generating a rotating force used to **power the wheels of a cart**, the barrel of a **washing machine**... If it is a kind of magic where you can enchant tiles to react logically together, then it is very similar to a **computer** and you can imagine advanced sorcerers working on diminishing the size of the logical tiles and augmenting the processing power... [Answer] There are actually a lot of works with magic set in modern or future world, off the top of my head: * Harry Potter (they don't interact much, but they did have a magical flying car) * Night Watch/Day Watch * Buffy (it was mostly vampire slaying but they did have witches with spells as well) * Practical Magic * Secret Circle * Beautiful Creatures * Arguably anything involving super heroes And there are a LOT more that I'm forgetting, so no there is no reason why magic *has* to be in medieval settings, but it does tend to be more hidden in modern settings since compared to modern weapons a magical person isn't as overpowered and have to keep it on the down low so that they aren't experimented on or shot by paranoid neighbor etc. [Answer] There are plenty of novels with magic and magical creatures in contemporary times. Usually under a genre called Urban Fantasy. Most current vampire and werewolf stories fall into this. Hard Spell by Justin Gustainis is magic and magical creatures on the East coast. If you want a book closer to "High Fantasy" that still contemporary you have the series like Harry Potter. [Answer] There is no requirement that magic and medieval tech have to be tied. Yes it has very frequently been done — probably around 4 to 1 with 'modern' tech and magic (given my library/readings). There are in universe type explanations that can be applied, specifically: * lots of research would be done into magic rather than technology * Magic users might be anti-technology due to technology reducing their power Then there are real world reasons: * for some reason a lot of people like dragons and knights (and similar themes) * a lot of early magic tales (i.e. fairy tales) were medieval in age. [Answer] Not at all, D&D 3.5 released Eberron, which has a much higher level of technology, often powered by magic. It's often compared to the late 19th, early 20th century in terms of the level of technology involved. There's also the Rifts universe that has high tech, with lasers and mechs, but also incorporates magic and psionics. They specifically have a tech called Techno-Wizardry, which mixes the two together. These are just the two universes I could think of off the top of my head. Whilst it's true that a large number of high-fantasy games use magic, it's certainly not exclusively that way. [Answer] To make a counter exemple, in the game "[Arcanum](https://en.wikipedia.org/wiki/Arcanum:_Of_Steamworks_and_Magick_Obscura)", both magic and steam-level technology (i.e. train, gas, guns...) co-exist. In fact, magic is studied like a science (i.e. at university; theories exist and so on...), but on separate (and distant) ground of the technological science. The reason is that magical operations modify the "standard" laws of nature, and that technology is based on those laws. If a spell as the side effect of modifying the coefficient of friction of metal, then the nearby steam-engine is going to have a problem. In this society, you have tech zones and magical ones, where the usage (or even the presence) of the opposing tech is forbidden. The society as a whole use both, depending on the need. For example, steam trains are more effective to move large quantity of people/material than magic, so there are railway stations in most big cities. [Answer] It's not a requirement for it to be medieval, it's just easier on the mind for some writers. I purchased a book of 30 wizard "short stories" some time ago and several involved modern day uses. With magic, you're limited only by your imagination. One such story involved magic being essentially code, you coded a spell and you could carry spells in your cell phone or a Zune and cast them by bringing them up. You had to sacrifice some 'mojo' to do so (The resource they had) but otherwise magic was pretty much an app that almost anyone could use. Getting 'mojo' apparently required some work though, IIRC you essentially sucked it out of people who visited your sites as sort of a fee. A particular spell I loved was the D\*ck Cactus curse, which does exactly what it implies and turns the organ into a cactus, with painful results. [Answer] The scientific method is based on results that are reproducible, through consistent rules that operate on the lowest level. If physical law were teleological instead, an attempt to understand physics would be more like psychology or politics. It would have more in common with Madison Avenue than Mathematics. Success in predicting or intentionally producing desired results wouldn't be utterly perfect but would be like modern understanding of Economics. [Answer] Look at the video game "[Destiny](http://destinytimeline.com/)" for a sci-fi plus magic setting. The Lore miraculously mixes sci-fi, with time travel, harnessing power of suns, giant supercomputers that gain sentience, and fantasy, with ancient Gods imposing their will across dimensions and space, performing rituals and such. [Answer] Because normal people and even doctors sometimes can hardly differentiate magic from super advanced technology. Therefore a magic setting in the future is indistinguishable (at first) from an actual SciFi. Some people say Star Wars is an example of magic and the future, some say even Star Trek is not a real SciFi but because it has magic in it. [Answer] ## Absolutely not. There are all sorts of lighter-hearted examples, but you can find rock-hard magic sci-fi out there too. For reasons that are not clear to me, it very often has a strong feminist bent (which is neat, though I don't see any reason it has to be that way). Some quick examples: * Melissa Scott's *[The Roads of Heaven](https://rads.stackoverflow.com/amzn/click/com/B00005XTAM)*. (Sorry for amazon link; couldn't find a better one quickly.) Masterful worldbuilding, good characterization. Kind of a firefly vibe. * Max Gladstone's *[Empress of Forever](https://www.goodreads.com/en/book/show/40380954-empress-of-forever)*. Space Opera. * Michael Swanwicks' *[The Iron Dragon's Daughter](https://en.wikipedia.org/wiki/The_Iron_Dragon%27s_Daughter)*. Sui generis. Just... go read the description. All three are excellent books that sprang instantly to mind. They are all easily described as Sci-Fi with advanced, post-industrial civilizations, and all revolve around magic. [Answer] **Magic and Super heroes** We always want to see somebody with extraordinary powers. In old days, he was a magician or a witch. In modern days, he is a super hero like Superman, Spider-man etc. In old days, some magicians or witches were good and some bad. Now some supermen are good and some bad (such as three Kryptonians in Superman II). Common things in magicians and super heroes are * They can do thing which humans can't do. * Good ones fulfill the wishes of good people, bad ones fulfill the wishes of bad people. * Bad people always find a bad one to counter the good one. ]

[Question] [ Questions about how to feed a large population keep popping up on this website quite frequently. One obvious option is farming. But how many people can you feed per square-kilometer of farmland? Interesting would be a comparison depending on the farming method used: * prehistoric methods * medieval methods (irrigation and simple tools) * modern methods (powered machines, industrial fertilizer and pesticides, applying findings from biology and agriculture as a science) * high-tech methods (hydroponics, genetically-modified crops and other high-tech methods which are currently working under lab conditions but not yet widely used for food production). I believe it would also be useful to compare farming efficiency depending on climate, because I think that this will have a great effect, especially on low-tech methods. I tried to find sources for this using search engines, but was unable to find a reliable one. [Answer] **Conventional Farming** According to [this source,](http://www.fao.org/docrep/t0207e/T0207E04.htm) the highest caloric density food is sweet potatoes, which provide 70,000 kcal/ha/day. (with potatoes providing 54,000 which is roughly in line with what ArtOfCode calculated.) This involves fairly intensive farming, so we'll need to let the land lie fallow for about a third of the time, reducing our long-term average to around 47,000 kcal/ha/day for our most dense food crop (in terms of kcal.ha/day). This is achievable with fairly primitive technology. This corresponds to 4,700,000 kcal/km2/day, which can feed **2350 people** on a 2000 kcal/day diet of pure sweet potatoes. **Hydroponics** Now let's see how we can increase that yield. The first thing we can do is to employ hydroponics. According to [this source,](http://www.sciencedirect.com/science/article/pii/S0304423807003846) hydroponics will increase our raw yield by around 280%. In addition, we won't have to let our fields lie fallow, since we no longer have any soil that we're growing plants in. This increases our base of 70,000 kcal/ha/day to 266,000 kcal/ha/day, which will feed **13,300 people** per square kilometer. **Aeroponics** Currently, individuals are researching an even better way of growing crops: aeroponics. In an aeroponic farm, nutrient rich water is vaporized to form a mist that is then sprayed onto the roots of crops. [This source](http://www.researchgate.net/publication/234520423_Comparison_of_vegetative_growth_and_minituber_yield_in_three_potato_variety_in_aeroponics_and_classic_hydroponics_with_three_different_nutrient_solutions) found that, with the correct nutrient solutions, they were able to increase yield over conventional hydroponics by between 50% and 270%. Assuming that, with further refinement, the upper end of this can be realized, we should be able to increase our sweet potatoes to 98,420,000 kcal/km2/day, which can feed a total of **49,210 people** on a 2000 kcal/day diet of sweet potatoes. **What else could we do to increase this?** So far, all of this has been constrained by sunlight: we can only grow one layer of crops if our crops get energy from the sun. Of course, if we can fire up a fusion generator to illuminate our crops with artificial, light, we can stack layers of crops on top of each other. In this case, a better measure might be kcal/km3/day. A sweet potato is about a meter tall, so we can grow 1000 layers of them in a 1km3 densely packed fusion powered green house. Our cube, using aeroponics, would produce 98,420,000,000 kcal/km3/day and could feed a population of **49,210,000 people.** Genetic engineering might be able to increase this even further, but this is about the right order of magnitude. [Answer] The question is *way too broad*, since there are many crops, land types and soil fertility levels, climate zones, technological levels, amounts of labor and capital that is available. These will dramatically affect what you get from given area. Moreover, there are many ways of transforming those crop calories into foodstuffs. For instance, do you eat the cereal or do you feed it to livestock, and then eat the livestock? Or perhaps you choose to distill your cereal and make bourbon... This could easily be a whole essay. For now, I'll restrict myself to **modern era practices**, since they range from essentially *medieval tech* to the *most modern methods*, so a cross-section through space is, in a sense, also one through time in this case. Crop yield varies a lot by crop, and is defined in two ways. The first is a ratio of seed to harvest, for instance 20:1 would mean that for every grain planted, you get 20 grains of harvest. The second definition measures output per area, and there are a myriad definitions, but the most common in modern times is yield in kg per hectare. As there are 100 sq. hectometers in a sq. km, one needs to simply multiply the answers by 100 to get your final answer. There are a multitude of sources on this for the modern world. Perhaps the easiest is the [World Bank.](http://data.worldbank.org/indicator/AG.YLD.CREL.KG) I've linked the cereal yield. Obviously you can have mushroom yield, fruit output per hectare of orchard, etc. As you look through the table linked above, you'll see an astonishing amount of variation, which has partially to do with climate variation, but mostly with the degree of mechanization and the size of farms (smaller farms tend to be less efficient and less mechanized). Low development countries in the present day have low yields, sometimes significantly under a ton per hectare (barely above replacing the seed grain!), while countries like France, US and Belgium have yields in the 6-10 ton/ha range. And this is just grain. [Potatoes](http://www.teara.govt.nz/en/market-gardens-and-production-nurseries/page-3), on the other hand, not only grow in hilly and rocky areas where you can't grow grain, but under careful cultivation and with pest-control, can currently deliver something like 80 tons/ha, whereas the first varieties that were introduced in Europe (this is after a few thousand years of Andean selection) only gave 13tons/ha. Finally, hydroponics can increase yields for a large variety of plants anywhere from 6 to 30-fold. Howard Resh has a book called [Hydroponic Food Production](http://rads.stackoverflow.com/amzn/click/1439878676). > > Identical cucumber plants produced 7,000 pounds per acre in soil but > 28,000 pounds per acre when grown hydroponically and tomato yields > that ranged from 5 to 10 tons per acre in soil but 60 to 300 tons per > hydroponic acre. The reported results are typical for practically any > plant. Said another way, to produce the total number of tomatoes > consumed annually in Canada (400 million pounds) requires 25,000 acres > of soil. Hydroponically, it would require only 1,300 acres. > > > --- Now one [kg of wheat is about 3400 Calories](http://www.traditionaloven.com/culinary-arts/flours/whole-wheat-flour/convert-kilogram-to-calories-kilocalories.html). A human needs about a million Calories per year (2700 Cal/day for 365 days), so that would be 294kg, (ignoring varied dietary needs for a sec). So one modern, say Belgian cultivated (yield 9t/ha) hectare of wheat would feed 30 people. **So one sq. km would meet the *calorie* needs of about 3000 people**. Obviously you will want meat, and other fruits and vegetables, so you could cut that to about a third (wheat --> meat has relatively low efficiency), so you could easily feed 1000-1500 people from a sq. km. of fertile modern-tech cultivated land. With hydroponics or other green-house style tech, and providing your own light, you could go **a lot** higher. If you covered the Earth in arcologies and dedicated a significant fraction to climate and light-controlled greenhouses, you could support trillions of people on Earth. [Answer] You might well be interested in my answer to [this question](https://worldbuilding.stackexchange.com/questions/7155/how-big-should-be-a-terrarium-to-be-self-sustained/7209#7209), as it details minimum requirements. In it, I do some calculation to find out that to feed one average human for a year, you need 5110 potatoes and 460 square metres of space. That takes care of one year, but if you plant potatoes again the next year you need to plant them somewhere different next year. That means you need 920 square metres per person per two years. You can cycle between two different locations with potatoes so that's all you'll need. So: There are $ 1000^2 = 1,000,000 $ square metres in one square kilometre. There are $ \frac{1,000,000}{920} = 1086.9565 $ 920-square-metre plots in a square kilometre, so you'd just about squeeze 1087. So, you can feed a maximum of 1087 people per square kilometre (ppsk) if they all live on nothing but potatoes. You would of course also need living space for all of them. --- That gives a bit of an estimate to what you can do. Let's compare that with population and see what the ratio of living space to farmland is. A decent size, single person house is around 50 square metres floor space. If you have 1087 people and a square kilometre of farmland, that means you're going to need: $$ 1087 \times 50 = 54350 $$ square metres of living space. That's 0.054 square kilometres. Therefore the ratio is: $$ \text{farmland} : \text{ living land} $$ $$ 1 : 0.054 $$ $$ 18.8 : 1 $$ That's quite a large space requirement. If you have a 5km radius city, it needs a 21km wide farming zone around it to fully support all its inhabitants. This is possible, but inefficient - this is why much of our food is imported from other countries with lower population and more farming space. [Answer] With current farming technology as actually practiced in the United States [about 10 acres of land](http://www.science20.com/news_articles/urban_agriculture_only_1_percent_of_seattle_residents_could_eat_locally_even_with_all_viable_space_in_use-163422) (40,000 square meters) is used to produce food for each average person. This itself represents are [remarkable improvement in agricultural productivity](https://en.wikipedia.org/wiki/Agricultural_productivity#U.S._Agriculture_productivity) in the last half century or so. > > Between 1950 and 2000, during the so-called "second agricultural > revolution of modern times", U.S. agricultural productivity rose fast, > especially due to the development of new technologies. For example, > the average amount of milk produced per cow increased from 5,314 > pounds to 18,201 pounds per year (+242%), the average yield of corn > rose from 39 bushels to 153 bushels per acre (+292%), and each farmer > in 2000 produced on average 12 times as much farm output per hour > worked as a farmer did in 1950. > > > Globally, [we use about a third as much land](https://ourworldindata.org/land-use-in-agriculture/) to product the same amount of food as we did fifty years ago, and agricultural productivity per land area has increased steadily year in and year out. The highest cereal yields per acre in the world in Kuwait and some Caribbean islands (in both cases, where arable land is at a premium) are [about three times as great](http://data.worldbank.org/indicator/AG.YLD.CREL.KG) as in the U.S. Still, farming in the U.S. is organized to optimize dollars of food output per dollar of food production cost, not to optimize caloric output per square meter of land (as you might want to in a space colony or starship or biosphere), because the U.S. has vast amounts of arable land available to it. The easiest way to maximize calories per square meter per year relative to the status quo would be to replace lots of meat with lots of plants in the average person's diet. Soybeans for example use [about 5% as much land](https://en.wikipedia.org/wiki/Edible_protein_per_unit_area_of_land) to generate the same number of protein calories as cows. > > Soybeans produce at least two times more usable protein per unit area > than any other major vegetable or grain crop, except for hemp which > can produce up to 33 g/m2 (290 lb/acre). They produce 5 to 10 times > more protein per unit area than land set aside for grazing animals to > make milk, and up to 15 times more protein per unit area than land set > aside for meat production. > > > And, how much meat does the average American eat? > > In 2012, the average American consumed 71.2 pounds of red meat (beef, > veal, pork, and lamb) and 54.1 pounds of poultry (chicken and turkey), > according to the U.S. Department of Agriculture. The average amount is > likely a bit higher. The USDA doesn’t take into account vegetarians, > who consistently represent about 5% of the population, according to > Gallup polls. > > > And meat and dairy and fats, all of which usually have animal sources, [make up almost exactly half of the average American's diet](http://blogs.wsj.com/numbers/how-much-meat-do-americans-eat-then-and-now-1792/). [](https://i.stack.imgur.com/UY7rF.jpg) Now not all plants are as efficient sources of protein in particular, or calories in general as soybeans, and eating soybeans all the time gets old (and doesn't supply all of the ammino acids needed to live by itself). But, it is fair to say that you could reduce the land footprint of the food an average person eats by about 45% (90% of the half from animals) by switching to an almost purely vegan diet. This is still a lot of farmland per person, about 5.5 acres per person (about 22,000 square meters). And, exactly how much improvement you could get with higher technology approaches like hydroponics, twenty-four hour grow lights and so on, isn't exactly clear. Assuming that an enclosed environment could at least match the peak productivity of cereal crops per land area relative to the U.S., it might be possible to reduce the amount of farmland per person required to a bit less than 2 acres per person (about 8,000 square meters, which is 125 people per square kilometer if one is answering the title question). Allegedly, hydroponic farming could significantly improve on even this 80% reduction from the status quo in food produced per acre, as the posts above note. But, estimates of 500-1000 square meters per person do seem unrealistic given current technology. [Answer] TL;DR answer: 111 people per square kilometer Explanation: A simple way of looking at this question is to divide the total amount of agricultural land worldwide by world population. This equation ignores waste and people who are starving, assumes humans don't eat fish from the oceans, and assumes farming methods worldwide are equally efficient (they aren't). Regardless, this answer is far closer to reality than the other answers provided. 36,480,000,000 acres - Total land mass of Earth 13,497,600,000 acres - Land used for agriculture (37% in year 2,000) 6,082,966,429 - World population (year 2,000) So if we divide 13,497,600,000 acres by 6,082,966,429 humans, we can say that each human on the planet requires 2.218 acres of land in order to eat. Since a square kilometer is roughly 247 acres, that much land can feed 111 people. [Answer] My ex is a gardener and I read an [article](http://www.for.se/pages/slurapport_om_hur_mkt_som_kan_produceras.pdf) that stated that you could feed a person (vegan only, no meat) on only 800 m2 in a temperate climate (Sweden in this case) using no hi-tech methods just planting things close and having several harvests per season. The crops used are potatoes, broad beans, carrots, parsnips, cabbage, onions and apples. Keep in mind that a hobbyist can plant things much denser than in industrial farming since the latter is focused on one crop and needs more space for the machines to work. [Answer] No matter how you tack the problem, you will be bound by physical limits. So I will restrain my answer to the physical aspects of the problem : **Solar irradiance** [](https://i.stack.imgur.com/KIcdf.png) No matter how effective the agriculture methods, you cannot yeld more energy per square meter than the ammount that reaches the soil. For one, according to this map, the solar irradiation is approximately 1900 kWh/M² on NE Brasil. Provided that the region is fertile, and it is, and has access to water, wich it does (this is one of the regions of Brazil where Sugar Cane is produced to later be transformed into alchool and become vehicle fuel) your limit on productivity will be roughly proportional to the efficiency of the plants at photosynthesis. **Photosynthesis efficiency** [](https://i.stack.imgur.com/Ot9nO.jpg) Modern sugarcane is one of the the most efficient plants at converting solar rays to sugar. It can reach efficiencies of 8%. This means that one square meter of sugar cane will, at the indicated area on the surface of the earth, produce ``` E = 5 kWh/Day * 0.08 = 400 Wh/day of sugar, or 1440 kJ of energy. ``` Glucose is the main sugar produced by sugarcane, wich holds 3000 kJ of energy per mol, circa 700 kcal/mol. This means that, each day, each square meter of crop area will produce ``` M = 1440 kJ / 3000kJ/mol = 0.48 mol of Glucose ``` Wich when converted to grams means ``` W = 0.48 mol * 180 g/mol = 86 g of sugar per day. ``` Aknowledging that your daily intake of food per day is not solely composed by sugar, all other plant material is the product of a subsequent transformation of this sugar into other materials, or, the energy provided by this sugar is used to cause chemical reactions that will produce those other substances. If the substance is not produced by the plant itself, it will be produced using this energy (protein, fat etc are produced at the expense of sugar by the plant itself or by animals that eat that plant and are subsequently eaten by humans). In other words, no food will ever hold, or spend being produced, more energy than this total ammount of sugar that the sugarcane produces per square meter. The normal male adult should eat 10500 kJ of energy per day, ``` A = 10500 kJ/day / 1440 kJ/day/M² = 7,29M² ``` wich means that 7.29 square meters of land should be cultivated in order to produce enough energy to sustain it, this, using the most efficient plant available, and expresed as pure calories (fat or sugar, but no vitamin or other regulatory food). This means that by a purely physical standpoint, using the most efficient plant available, by the most efficient method available, you need at least ~7 square meters of land to produce enough for a single adult male. Real world figures will be higher due to various inefficiencies. Food production and distribution is a complex activity and more than sugar is needed to sustain an human being, meaning that less efficient plants are needed in order to produce all nutrients needed. Meat is produced by feeding livestock with plant produced by the same process as sugarcane (photosynthesis), but each change of trophic level imples a certain loss of energy, so the meat produced by a certain ammount of land will be less than of those directly consumed as sugarcane. And so on. tl;dr With current types of crop, you will need at least ~7 square meters of land per adult male, no matter wich cultivation process, type of plant, meat or veggie, etc. This is a physical limit implied by photosynthesis limits. The only way around is increasing photosynthetical efficiency of plants by genetic manipulation. [Answer] Vertical hydroponic farms (doable with current technology): If you build a 100 floor hydroponic farm skyscrapper next to some massive water source on 1 square kilometer of land, you can basically feed an entire city. That would be an economic disaster and be unprofitable but it's technically doable. Vertical farming is not science fiction and is already being experimented now in some cities like Singapore. It s not really economically profitable since conventional farming is still super cheap but for some countries with limitied land like Singapore, having vertical structure using some advanced hydroponics (no soil needed) allows them to stack farmland vertically. Singapore is doing it to not depend too much on food import (policital reasons). Assuming energy and building cost become cheap enough or that arable land becomes rare enough, that would become economically viable. [Answer] I personally think it depends on the plant. Certain foods, such as corn, grow only one or two ears per stalk, whereas a tomato plant may grow 15 or more tomatoes throughout the season. Either way, you would need to rotate your crops every few years in order to be able to grow *anything*, so you'd have to be careful on what you did grow. I think what you'd really want to pay attention to is A) How much food does the plant produce and B) How healthy is the plant for the soil and C) What sort of vitamins will people gain from them. In my personal experience, grapes, tomatoes, green beans, carrots, and other foods that have take up minimal space will allow for more food overall, so I would say at least 10-25 acres, at minimum, more if you have the space. I don't know how helpful this really was, but I do hope it gave you some insight. [Answer] I draw fictional maps, and I did do these calculation. According to my calculation and assumptions, 1m2 of wheat field will produce 1x 700g (approx 1lb 8oz) loaf of bread. This assumes medium fertility of about 5 tons of grain per hectare. Herbivores eat 2% of their body weight per day, and a cow would require about 2/3 of a hectare per year (allowing the grass to grow back). My research shows that a meat animal is about 50% efficient: only half of the animal's weight can be converted to edible meat. [Answer] Under natural circumstances and farming organically without fertilizers and artificial chemicals or using GM technology, you cannot produce more than 500kg of grain (using wheat as an example) and that is just about enough to feed a person per year. Considering the vegetables, spices, and other condiments that must be cooked to be eaten with the bread, chapatis, or whatever else people make with flour to be eaten with the vegetables, we need an additional of about 3 hectares of land. That means 4 hectares per person per year under natural farming conditions. As there are 100 hectares in 1km^2, this amount of land can feed only about 25 people very well with a bit left over for comfort. ]

[Question] [ **This question asks for hard science.** All answers to this question should be backed up by equations, empirical evidence, scientific papers, other citations, etc. Answers that do not satisfy this requirement might be removed. See [the tag description](/tags/hard-science/info) for more information. Stars generate their energy by fusing lighter elements into heavier elements. The most common reaction in Sun-like stars is the conversion of hydrogen to helium via the proton-proton chain, but heavier elements can also be synthesized, typically in more massive stars. Before nuclear fusion was proposed as the source of energy for stars, there were other ideas put forth, notably the release of energy via gravitational contraction (i.e. the Kelvin-Helmholtz mechanism). Some stars release energy in this way while on the Hayashi track, but this is only for a short part of their lives. Could star-like objects exist that produce energy and support themselves against the force of gravity by means other than nuclear fusion? I'm also interested in ways that a civilization could make one of these star-like objects. --- Note, **and a reminder to folks writing up new answers**: This is a [hard-science](/questions/tagged/hard-science "show questions tagged 'hard-science'") question. An answer needs to prove that the mechanism given will be a stable source of energy that will last on timescales similar to those of typical stars, without any catastrophic events. A helpful text can be found [here](http://www.ucolick.org/~woosley/ay112-14/texts/pols11.pdf). [Answer] As another answerer provided, Neutron stars already do this. So, I'm going to alter my answer somewhat to address whether there are other means by which a star-like object may exist, besides the one we already know about. In that regard, I'm afraid my ultimate answer to this is going to be 'No' or at least 'Not with our current laws and/or understanding of physics.' However, lets start by defining additional parameters that are necessary **Size** To be 'Star Like' we need to be about the same size as a star. Something that has a notable gravity well. In your comments, you also nixxed black holes, so those are out as they are not as stable, and to 'produce' light, would need a constant feed of matter supplied to their accretion disk. And even then, that light is produced in part by fusion. **Self-sustaining and Regulating** We need a reaction that can keep itself going, but not go too fast. Fusion is great for this...the primary requirement for Fusion is 'high density, high temperature.' Gravity creates that environment all on its own, and the Fusion reaction in a star stabilizes it. Gravity smashes all the Hydrogen together, increasing pressure and temperature until fusion begins. If the rate of fusion gets too low, the pressure from gravity speeds up the fusion. If the rate of fusion gets too high, the outward pressure of the reaction reduces the density, and ultimately slows the fusion back down. It's a reaction that is perfect for running an extremely long time...particularly since most of the star's supply of hydrogen is NOT held at fusile pressures at any given time. **Must produce enough energy to *prevent* Fusion** With enough temperature and pressure, fusion will begin. With massive enough elements (iron or heavier), this is a endothermic reaction which results in the death of the star. Our 'pseudo-star' needs to produce enough energy to resist gravity crushing it down and igniting fusion, or it will either turn into a star, or destroy itself as the high-mass fusion sucks all the energy out of the pseudo-star (depending on the mass of the materials it is made of). To produce that much energy, but still live on...we need an extremely high-energy reaction, comparable to Fusion, but efficient enough to maintain pace. So, really, we need something with a similar energy density to Hydrogen, when used for Fusion. So, with these extra constraints in place, lets look at some options for producing this sort of energy. 1: Chemical Reactions: These are out. Completely. Fusion and Fission produce millions of times more energy per kg of reactant than any chemical reaction. In order to maintain a reaction that could keep up with Fusion or Fission, we'd burn through our fuel supply very quickly [ref](https://en.wikipedia.org/wiki/Nuclear_fission) [ref2](http://www.whatisnuclear.com/physics/energy_density_of_nuclear.html) [ref3](http://www.plux.co.uk/energy-density-of-uranium/) 2: Fission. The reverse of fusion seems like a good idea at first, but there are a few problems. First off, Fission is a runaway reaction. You need a critical mass of the compound and then some neutrons need to be fired at the compound at a very high speed. From there on, unless controlled by external sources, Fission will spread exponentially through the fuel, and continue spreading and increasing in rate until the entire amount of fuel has been consumed. A star-sized fission reaction would be more like a supernova than a star. The second problem is that fission needs an ignition source, so it likely cannot occur in nature. [ref](http://www.diffen.com/difference/Nuclear_Fission_vs_Nuclear_Fusion) [ref2](https://en.wikipedia.org/wiki/Nuclear_fission) 3: Antimatter: The only reaction we are aware of that is more powerful than Fusion. But, again, anti-matter is a runaway reaction. If matter and anti-matter are mixed, they will annihilate any time the two pieces come into contact. There is only one means to regulate an antimatter reaction, and that is to intentionally keep the matter and anti-matter separate until you want them to react. This is not something that would happen in nature. [ref](https://en.wikipedia.org/wiki/Antimatter) We do not currently know [how Anti-matter interacts with gravity,](http://www.pbs.org/wgbh/nova/blogs/physics/2014/11/does-antimatter-fall-up-or-down/) but the two main possibilities are that it either obeys gravity normally, or is repulsed by gravity. In the former case, the antimatter and matter would be pulled together by gravity and either annihilate entirely, or if enough came together at once (even by coincidence of convection) would unleash enough energy to shred our 'pseudo-star' to pieces. Even if it could pull itself back together somehow, we do NOT have a stable system here. In the latter case, matter and anti-matter would repulse each other on a gravitational level, and without someone intentionally throwing them at each other, they would not naturally interact, and would certainly not form a star-like object 4: White Hole. A fun piece of theoretical physics that has largely been debunked. The idea was originally that black holes were holes in spacetime, and white holes were where everything they sucked up was expelled. All that light it spewed out would look an awful lot like a star. However, this only fits with the 'eternal blackhole' model for black holes, and a black hole created by gravitational collapse, and balanced by hawking radiation (read: every black hole we have ever found) do not allow for the existence of a White Hole. Furthermore, White Holes violate the Second Law of Thermodynamics, in that they actually would decrease entropy. The only remaining theory supporting White Holes is that they are actually a 'Big Bang,' not a Star-like object. [ref](https://en.wikipedia.org/wiki/White_hole) **Conclusion** Unless I skipped some form of energetic but self-regulating reaction, it doesn't look like this is feasible, even from a purely logical standpoint. With our current understanding of the universe, it does not appear that a star-like object that fits all the necessary longevity requirements is possible. [Answer] The closest mechanism I can find would be a pulsar star. I'm not an astrophysicist so my explanations may not be the best, but: 1. A pulsar is a neutron star, *which holds itself together without using fusion*1 2. They can produce equal to/more energy2 than the sun 3. They actually do exist (it isn't science fiction) --- # Notes 1 > > Neutron stars are very hot and are supported against further collapse > by quantum degeneracy pressure due to the phenomenon described by the > Pauli exclusion principle, which states that no two neutrons (or any > other fermionic particles) can occupy the same place and quantum state > simultaneously. > > > Source: [Wikipedia: Neutron Star](https://en.wikipedia.org/wiki/Neutron_star) > > > 2 A [calculation](https://books.google.ca/books?id=jCPn3v-o_KoC&pg=PA117&lpg=PA117&dq=energy%20output%20of%20a%20pulsar&source=bl&ots=hSBiXQamsR&sig=f11EvuTa1hWwY6xCELbd2OzmfQU&hl=en&sa=X&ved=0CCMQ6AEwAWoVChMI7tzu4d6wxwIVgRs-Ch02sAFJ#v=onepage&q=energy%20output%20of%20a%20pulsar&f=false) (Page 118) of the Crab Pulsar states that it has an energy loss of 4.5\*10^31 J/s. But it only radiates 1% (4.5\*10^29 J/s) through X-rays and Gamma rays. The sun's total energy output per second is [estimated to be 3.8\*10^26 J/s](http://helios.gsfc.nasa.gov/qa_sun.html#sunenergymass). To put these calculations in perspective: > > The tiny Crab Pulsar, which is not much more than 10 kilometers in > diameter, powers the enormous energy output of the Crab Nebula, which > is 10 light years in diameter. To set things in perspective in terms > of relative sizes, this is as if a 1 kilometer wide volume of space > were radiating strongly at various wavelengths and most of the power > were being supplied by a single hydrogen atom at the center of that > volume! > > > Source: [Pulsars on csep10.phys.utk.edu](http://csep10.phys.utk.edu/astr162/lect/pulsars/pulsars.html) > > > [Answer] # Use a Quasi-star. The solution I think will finally work is to use a [quasi-star](https://en.wikipedia.org/wiki/Quasi-star), a theoretical object from the early universe consisting of a black hole of perhaps $10M\_{\odot}\text{-}100M\_{\odot}$ surrounded by a gas envelope of up to $1000\text{-}10000M\_{\odot}$. These objects generated energy from gravitational potential energy as matter from the inner boundary of the envelope fell into the central black hole. Fusion did not take place in the envelope, meaning that young, small quasi-stars could have appeared, to the naive observer, to be simple very massive stars. Basically, a quasi-star is a black hole surrounded by a large cloud of gas around a black hole. It's extraordinarily massive, and looks a lot like a giant star. The big difference, though, is that a quasi-star produces energy from changes in potential energy caused by the black hole sucking in gas - there isn't any significant fusion happening. (Summary suggestion courtesy of [AndyD273](http://chat.stackexchange.com/transcript/0?m=37251253#37251253).) The goal of this answer is to determine some properties of a quasi-star that could fit our specifications. Most of the answer is math, graphs, and code; the above summary is probably the most qualitative explanation I have. I’ll create an approximate polytropic model via numerical integration after determining some of the thermodynamic quantities in the object’s core. Polytropes are generally very good approximations to stars and star-like objects at most places inside them, and I’ve found that my results appear to match more detailed models. My primary references here are [Ball et al. (2011)](https://arxiv.org/abs/1102.5098) and [Fiacconi & Rossi (2016)](https://arxiv.org/abs/1604.03936). There are some differences in equations, which I’ll point out, but it turns out that they’re actually negligible for the right parameters. # Polytropes I'm going to start this answer with a review of polytropes and some simple methods used to create reasonable models of quasi-stars. Fiacconi & Rossi justify the choice of a polytropic model (with $n=3$) by writing > > the envelope represents the majority of the mass and volume of a quasi-star and convective regions can be described accurately by an adiabatic temperature gradient > > > In short, the conditions in most parts of the envelope are non-relativistic and are similar to those inside a large star. Polytropic models for stars are quite well represented using $n=3$. A [*polytrope*](https://en.wikipedia.org/wiki/Polytrope) is an object that obeys the equation of state $$P=K\rho^{(n+1)/n}\tag{1}$$ where $P$ and $\rho$ are density and pressure, $K$ is a constant, and $n$ is the *polytropic index*. The quasi-star can be assumed to be in [hydrostatic equilibrium](https://en.wikipedia.org/wiki/Hydrostatic_equilibrium), meaning that pressure (dominated by radiation flowing outward) balances the force of gravity: $$\frac{dP}{dr}=\frac{\rho GM}{r^2}$$ where $G$ is the gravitational constant, $M$ is the mass contained within $r$, and $r$ is the radial coordinate. By inserting the polytropic equation of state in the equation of hydrostatic equilibrium, we eventually arrive at the [*Lane-Emden equation*](https://en.wikipedia.org/wiki/Lane%E2%80%93Emden_equation): $$\frac{1}{\xi^2}\frac{d}{d\xi}\left(\xi^2\frac{d\theta}{d\xi}\right)=-\theta^n\tag{2}$$ where $\theta$ is a specific function relating to the main thermodynamic variables (density, pressure, and temperature) and $\xi$ is a dimensionless radius. Analytical solutions only exist for three values of $n$: $n=0$, $n=1$, and $n=5$. Unfortunately, the case we’re interested in is for $n=3$, applicable to most main sequence stars as well as quasi-star envelopes. Therefore, we have to use numerical methods. We can make the Lane-Emden equation easier to solve by casting it in the form of a pair of coupled differential equations: $$\frac{d\theta}{d\xi}=\phi,\quad\frac{d\phi}{d\xi}=-\theta^n-\frac{2}{\xi}\phi\tag{3}$$ The normal practice is to solve these via a [Runge-Kutta method](https://en.wikipedia.org/wiki/Runge%E2%80%93Kutta_methods), typically of fourth order (denoted RK4). In general, RK4 is superior to most lower-order methods. However, for some cases, it’s not necessary. I’ve found that for small enough step sizes for each method, the [Euler method](https://en.wikipedia.org/wiki/Euler_method) works nearly as well, and is simpler to write - and computationally a bit cheaper. I’ll end up using it here. To hopefully convince you of this, I’ve implemented both methods in Python for an $n=3$ polytrope. I used a step size of $h=\Delta\xi=10^{-4}$, and I got excellent results: [](https://i.stack.imgur.com/AdbxD.png) The top graph plots $\theta\_{\text{RK}4}(\xi)$ and $\theta\_{\text{E}}(\xi)$ for $0\leq\xi\leq10$, where $\theta\_{\text{RK}4}$ and $\theta\_{\text{E}}$ are the solutions of the Lane-Emden equation using the RK4 and Euler methods, respectively. Some of the values (where $\theta<0$ are unphysical, but I’ve plotted them anyway to show the long-term behavior. The bottom graph plots $\theta\_{\text{RK}4}(\xi)-\theta\_{\text{E}}(\xi)$. The values for this are quite small, less than $\sim10^{-5}$ for most $\xi$. # Key properties of quasi-stars Most treatments of quasi-stars use slightly different forms of the Lane-Emden equation, with solutions called *loaded polytropes* which have cusps near the center. All have different boundary conditions than than ours. Our conditions were $$\theta(\xi\_0)=1,\quad\phi(\xi\_0)=0,\quad\xi\_0=0\tag{Ordinary b.c.’s}$$ When modeling a quasi-star, however, we do *not* integrate from $\xi\_0=0$, but from a radius $r\_0$ related to the [*Bondi radius*](https://en.wikipedia.org/wiki/Bondi_accretion) $r\_B$ of the central object. In terms of unscaled distances, this is given by Fiacconi and Rossi as $$r\_0=br\_B=b\frac{GM\_{\bullet}}{c\_{s,0}^2}\tag{4a}$$ where $M\_{\bullet}$ is the mass of the black hole and $c\_{s,0}$ is the speed of sound in that region. Their substitution for $r\_B$ appears to be smaller by a factor of four; however, this discrepancy goes away for the right choice of $b$. The authors use several other important quantities and relationships: $$\xi\_0=\frac{3b}{2}\phi\_0\tag{4b}$$ $$\phi\_0\approx2q,\quad q\equiv M\_{\bullet}/M\_\*\tag{4c}$$ $$\rho\_0=\left[\frac{(n+1)^3}{4\pi G^3}\right]^{\frac{1}{4}}\frac{\phi\_0^{1/2}P\_0^{3/4}}{M\_{\bullet}^{1/2}}\tag{4d}$$ where $M\_\*$ is the envelope mass. It should be noted that the $\phi\_0$ in these equations is not quite the same as the $\phi\_0$ used in the classical Lane-Emden equation; I’ll get back to this later. Ball et al. give us another relevant relationship between $\xi\_0$ and $\phi\_0$: $$\phi\_0=\frac{1}{2n}\xi\_0+\frac{2}{3}\xi\_0^3\tag{4e}$$ This would seem to not be compatible with $(\text{4a})$ for most $\phi\_0$ and $\xi\_0$. However, it seems that this all works out. First, Fiacconi and Rossi describe $b$ as “of the order of few”. That should indicate that $1\leq b\leq10$, give or take. If we choose $b=4$, then their $\xi\_0$-$\phi\_0$ equations gives $\xi\_0=6\phi\_0$. Now, we also know that $q\simeq10^{-4}$ to $10^{-2}$. If we take $q=10^{-3}$, and use $\phi\_0\approx2q$, we get $\phi\_0\simeq2\times10^{-3}$. Plugging this into $(\text{4e})$ gives us $$\phi\_0=\frac{1}{2n}\xi\_0+\frac{2}{3}\xi\_0^3=2\times10^{-3}$$ via [Wolfram Alpha](http://www.wolframalpha.com/input/?i=solve+2*10%5E(-3)+%3D+x%2F6%2B(2%2F3)x%5E3), or $\xi\simeq0.012=6\phi\_0$. Both equations are nearly in agreement. We want our quasi-star to be relatively tiny, as quasi-stars go, so let’s say that $M\_{\bullet}=1M\_{\odot}$. Since $q=10^{-3}$, that means that $M\_\*=100M\_{\odot}$, giving us a total mass of $M\_{\text{tot}}=M\_{\bullet}+M\_\*=101M\_{\odot}$. That’s reasonable - much more massive than the Sun, but still able to pass for a normal star. We should also choose a suitable central pressure - perhaps $P\_0\simeq5\*10^{10}\text{ erg cm}^{-3}=5\times10^9\text{ J/m}$. Plugging this into $(\text{4d})$ gives us $\rho\_0\simeq5.426\times10^{-5}\text{ g cm}^{-3}$. This matches the progression of densities of the models of Ball et al. (Figure 1 and Table 1; their lowest $M\_{\bullet}$ is $5M\_{\odot}$, with a central density of $\sim8.71\times10^{-5}\text{ g cm}^{-3}$). Both results are much lower than [the central density and pressure of the Sun](https://nssdc.gsfc.nasa.gov/planetary/factsheet/sunfact.html). In a polytrope, [the speed of sound is given by](http://www.astronomy.ohio-state.edu/~dhw/A825/notes3.pdf) $$c\_{s,0}^2=\gamma\frac{P\_0}{\rho\_0}\tag{5}$$ where $\gamma=(n+1)/n$, and so in our case $\gamma=4/3$. Therefore, we find that $c\_{s,0}^2=1.473\times10^11\text{ (m/s)}^2$. Plugging this into $(\text{4a})$ gives us a radius $r\_0$ of $1.802\times10^{9}\text{ m}\simeq2.6R\_{\odot}$. The Bondi radius is then $r\_B=r\_0/4\simeq0.65R\_{\odot}$. This again matches up; the Ball models had $r\_B\simeq1.66R\_{\odot}$ for $M\_{\bullet}=5M\_{\odot}$. The progression seems to make sense. # Boundary conditions We’re now ready to integrate the Lane-Emden equation for a quasi-star. First, we set it up as a different pair of coupled differential equations: $$\frac{d\theta}{d\xi}=-\frac{1}{\xi^2}\phi,\quad\frac{d\phi}{d\xi}=\xi^2\theta^n\tag{6}$$ The boundary conditions here are $$\theta(\xi\_0)=1,\quad\frac{d\theta}{d\xi}|\_{\xi\_0}=-\frac{\beta}{\xi\_0^2},\quad\xi\_0=r\_0/\alpha\tag{Quasi-star b.c.’s}$$ where $$\beta\equiv\frac{M\_{\bullet}}{4\pi\rho\_0\alpha^3}\tag{7}$$ The scaling factor $\alpha$ can be determined from its definition. Plugging in our values for $r\_0$ and $\xi\_0$, we get: $$\alpha=r\_0/\xi\_0=\frac{1.802\times10^9\text{ m}}{0.012}=1.502\times10^{11}\text{ m}$$ Therefore, we get $\beta=8.59\times10^{-4}$. Our boundary conditions can now be rewritten as $$\theta(\xi\_0)=1,\quad\frac{d\theta}{d\xi}|\_{\xi\_0}=-\frac{8.59\times10^{-4}}{\xi\_0^2},\quad\xi\_0=.012\tag{Quasi-star b.c.’s}$$ # The Euler method I’d like to first review the Euler method. Let’s say we have an ordinary first-order differential equation of the form $$\frac{dy}{dx}=g(y,x)$$ with appropriate boundary conditions; that is, we know $x\_0$ and $y\_0=f(x\_0)$. We want to find approximate values for the function $y=f(x)$ over some interval of $x$ starting at $x=x\_0$. We use the approximation $$\frac{dy}{dx}\approx\frac{\Delta y}{\Delta x}$$ and choose some small $\Delta x$. We then use the first equation to find $$\Delta y\approx g(y,x)\Delta x$$ and iterate along the interval: $$x\_{n+1}=x\_n+\Delta x,\quad y\_{n+1}=y\_n+\Delta y\_n=y\_n+g(y\_n,x\_n)\Delta x$$ This is the type of method I implemented along with RK4 to produce the first graphs, of an ordinary $n=3$ polytrope. For a system of differential equations like these, the extension is simple; we just have more functions like $g(y,x)$. # Results Now we can finally create our models. I used the same step size as in my original example - $\Delta \xi=10^{-4}$ - and plotted $\theta(\xi)$ on both normal and logarithmic $\xi$-axes, to show both the dramatic central cusp and the fact that for a loaded polytrope, $\xi\_0\neq0$. I wrote the code in Python 3: ``` import numpy as np import matplotlib.pyplot as plt n = 3 dxi = 10**(-4) xi0 = .012 phi0 = 8.59*10**(-4) def dtheta(phi,xi):     return (-phi/(xi**2))*dxi def dphi(theta,xi):     return xi**2*(theta**n)*dxi Xi = [xi0] Theta = [1] Phi = [phi0] while Theta[len(Theta)-1] > 0:     Xi.append(Xi[len(Xi)-1] + dxi)     Theta.append(Theta[len(Theta)-1] + dtheta(Phi[len(Phi)-1],Xi[len(Xi)-1]))     Phi.append(Phi[len(Phi)-1] + dphi(Theta[len(Theta)-1],Xi[len(Xi)-1])) plt.figure(1) plt.subplot(211) plt.plot(Xi,Theta) plt.title('Quasi-star solution to the Lane-Emden equation for $n=3$') plt.xlabel('Scaled radius') plt.ylabel('Solution') plt.subplot(212) plt.title('Quasi-star solution with logarithmic scale') plt.xlabel('Scaled radius') plt.ylabel('Solution') plt.semilogx(Xi,Theta) plt.show() ``` That’s pretty painless, and quick to write. Here’s the output: [](https://i.stack.imgur.com/snVah.png) I also did a comparison between a loaded polytrope and a normal polytrope for $n=3$, again to emphasize the cusp: [](https://i.stack.imgur.com/ostqN.png) Finally, here’s a set of graphs I made of normalized temperature, density and pressure for an $n=3$ loaded polytrope and an $n=3$ normal polytrope. While both temperature profiles are quite similar, there is a sharp difference in density and pressure near the core. [](https://i.stack.imgur.com/gUVru.png) Now, remember that these are merely *normalized* values, and should be multiplied by the central parameters, but the point remains: Quasi-stars are much different than normal stars. # Evolution The one remaining question is whether or not our quasi-star will remain stable for any significant amount of time. It’s certain that the mass of the central black hole will change, as the object is powered by accretion from the inner edge of the envelope. Eventually, the quasi-star will be pretty much a black hole with a little bit of gas around it. In the shorter term, the stability of the envelope, for instance, poses a potential problem. It will also be losing mass, as well as accreting it from a disk that may form, surrounding the entire object. Ball et al. found that $$\dot{M\_{\text{BH}}}\propto M\_{\text{BH}}^2\rho^{(3-\gamma)/2}\tag{8}$$ To within an order of magnitude, this remains around $\sim10^{-4}M\_{\odot}$ per year for many quasi-stars at various stages of evolution. Assuming that the envelope mass of our quasi-star is $\sim100M\_{\odot}$, then the envelope should be entirely accreted on a timescale of one million to ten million years, up to a factor of a few. That’s quite reasonable; massive stars typically travel through the main sequence on the order of one million to ten million years, and so while the quasi-star may live for only a short amount of time in comparison to the Sun, its lifetime is reasonable when compared to massive stars. # Will fusion be possible? One key assumption of quasi-star models is that any fusion is completely negligible. This particular quasi-star is certainly not normal, so I'd like to double-check and see if there will in fact be little or no fusion. We can do this by calculating the reaction rates of the quasi-star compared to those of the Sun. (I'd like to assume that any fusion occurs via the [p-p chain](https://en.wikipedia.org/wiki/Proton-proton_chain_reaction). The [CNO cycle](https://en.wikipedia.org/wiki/CNO_cycle) is not possible in a star without carbon, nitrogen or oxygen!) The rate of energy generation $q{ij}$ from a reaction of particles $\_i$ and $\_j$ is $$q\_{ij}=\overbrace{C\_1\left(\frac{1}{1+\delta\_{ij}}\right)\frac{1}{A\_iA\_j}\frac{1}{AZ\_iZ\_j}}^{S\_{ij}}X\_iX\_j\rho\tau^2e^{-\tau}Q\tag{9}$$ where $C\_1$ is some collection of constants not unique to the stellar environment, $\rho$ is the density, $X\_I$ and $A\_i$ represent mass fraction and mass number (while $A$ is [reduced (atomic!) mass](https://en.wikipedia.org/wiki/Reduced_mass)), $Z\_i$ is atomic number, $Q$ is the energy released per reaction, $\delta\_{ij}$ is the [Kronecker delta](https://en.wikipedia.org/wiki/Kronecker_delta), and $\tau$ is a peculiar function of temperature: $$\tau=C\_2\left(Z\_i^2Z\_j^2AT^{-1}\right)^{1/3}=D\_{ij}T^{-1/3}\tag{10}$$ where $C\_2$ is another constant. I've scrunched together a bunch of terms together as $S\_{ij}$; you'll see why later. Let's find the ratio of $q\_{ij,\odot}$ (the Sun) to $q\_{ij,\*}$ (the quasistar): $$\frac{q\_{ij,\odot}}{q\_{ij,\*}}=\frac{S\_{ij}X\_{i,\odot}X\_{j,\odot}\rho\_{\odot}\tau\_{\odot}^2e^{-\tau\_{\odot}}Q}{S\_{ij}X\_{i,\*}X\_{j,\*}\rho\_{\*}\tau\_\*^2e^{-\tau\_\*}Q}\tag{11}$$ Both factors of $S\_{ij}$ cancel out (as do the $Q$s), leaving us with something much simpler. For the quasi-star, we can look at the highest values of temperature and pressure, the central values we picked earlier. I'll take $\rho\_{c,\*}=5.426\times10^{-5}\text{ g cm}^{-3}$ and $T\_{c,\*}\simeq3.5\times10^{5}\text{ K}$, as per Table 1 of Ball et al. I already assumed that the quasi-star envelope is pure hydrogen, so $X\_i=X\_j=1$. For the Sun, I'll use the [BS05(AGS, OP) solar model](http://www.sns.ias.edu/~jnb/SNdata/solarmodels.html) by John Bahcall. This gives $X\_i=X\_j=0.36462$, $\rho=1.505\times10^2\text{ g cm}^{-3}$, and $T\_{c,\odot}=1.548\times10^{7}\text{ K}$. Substituting some of this gives $$\frac{q\_{ij,\odot}}{q\_{ij,\*}}=\frac{(0.36462)^21.505\times10^{2}\text{ g cm}^{-3}\tau\_{\odot}^2e^{-\tau\_{\odot}}}{(1)^25.462\times10^{-5}\text{ g cm}^{-3}\tau\_\*^2e^{-\tau\_\*}}=3.66\times10^5\frac{D\_{ij}^2T\_{\odot}^{-2/3}e^{-\tau\_{\odot}}}{D\_{ij}^2T\_\*^{-2/3}e^{-\tau\_\*}}$$ More substitutions give $$\frac{q\_{ij,\odot}}{q\_{ij,\*}}=2.9\times10^4e^{\tau\_\*-\tau\_{\odot}}$$ In our case, $D\_{ij}$ is $42.46\mu^{1/3}$, with $\mu$ being the reduced mass (note that $\mu\neq A$), if $T$ is expressed in mega-Kelvin (i.e. millions of Kelvin). We can figure out that $\tau\_\*>\tau\_{\odot}$ because $T\_{c,\*}<T\_{c,\odot}$, and therefore $$e^{\tau\_\*-\tau\_{\odot}}>e^0=1$$ Therefore, $\frac{q\_{ij,\odot}}{q\_{ij,\*}}\gg1$, and it appears that any fusion will be insignificant. ### References for reaction rate equations: * [Duke University](http://www.phy.duke.edu/~mkruse/PHY105_S11/Stellar_Reactions.pdf) * [TUM](http://www.nucastro.ph.tum.de/fileadmin/tuphena/www/lecture9_10_new_2010.pdf) * [UCSC](https://websites.pmc.ucsc.edu/~glatz/astr_112/lectures/notes8.pdf) # Conclusion I proposed that a low-mass quasi-star - a black hole surrounded by a large star-like gaseous envelope - could have similar properties to a massive star of $\sim100M\_{\odot}$. I took central pressure and density values of $5\times10^9\text{ J/m}$ and $5.426\times10^{-5}\text{ g cm}^{-3}$ for a quasi-star of envelope mass $100M\_{\odot}$ around a black hole of mass $1M\_{\odot}$. Temperature, density and pressure profiles using a polytropic approximation show that fusion is unlikely, even at the center, and therefore the sole source of energy from the quasi-star should be from accretion by the black hole. The object should remain stable for one million to ten million years, which is a reasonable lifetime. [Answer] I'll begin my response with an acknowledgement to those answers that came before mine. Each of them has, in one way or another, informed and inspired the avenues of my mind to construct a device which I hope fulfils the requirements of the question. The first and most prevalent restriction everyone appears to have assumed (and I work under no assumption) is that this object **must** be star-*sized*. Given the restriction that the object **must not** be fusion powered, it **must** therefore also not reach 'critical mass', so to speak, which is roughly 80 times the mass of Jupiter. These restrictions seem to be a more reasonable requirement: * $ 0.087 \text{ M}\_{☉} $ OR about $ 1.73 \times 10^{29} $ kg in mass * $ 4.85 \times 10^{23} $ Watts in power output * 14.35% luminous efficiency OR 98 lumens/Watt For these last two requirements I've referenced the least luminous normal star from Wikipedia and the efficiency of our own star, as we likely wish this light-emitting object to be of some use to an orbiting body. So, now to the 'idea' without the maths, as this idea requires exotic materials that have not yet been discovered. Having done more reading, I've found several possible variations and limitations. For example, if I stick my first idea and use a [thixotropic](https://en.wikipedia.org/wiki/Non-Newtonian_fluid) fluid and a [rheopectic](https://en.wikipedia.org/wiki/Non-Newtonian_fluid) fluid with unique properties (change of density when shifting from liquid to solid and being brittle when solid) causing them to exchange places in the 'mantle' via cracks, fissures, pieces moving around and liquidating again, generating frictive and compressive forces on each other, exhibiting one or a few [luminescent properties](https://en.wikipedia.org/wiki/Luminescence), such as piezoluminescence, cryoluminescence etc. I'm hoping the stellar sized masses and movements of these liquids will generate enough energy via several Luminescent types that it will generate light via a combination of these means. The reliance on these luminescent properties means relying on a poly-cyclical production of energy, hopefully not all at the same time, but unfortunately on geological scales. This creates a need for some kind of structure to store the energy and release it continuously. This structure will be some kind of stellar sized geodesic structure, the purpose of which will be to sit at the equilibrium point of the two fluids and can perform a variety of functions: * Collect electrical energy discharged from the polarized fluids * Discharge electricity in a continuous flow * Produce light at [400lm/W?](http://spie.org/x92145.xml) * Contract or expand as the boundary between the mediums changes tidally or otherwise * [Constrict the flow of one medium into the other to generate more energy?](http://www.kineticceramics.com/piez_fluid.html) I originally suggested some further improvements, notably the use of a crystalline core that is piezoluminescent/electric and/or the suspension of tiny crystals with similar properties within the two fluids. I believe now that using a crystalline core could be very problematic. Given the pressure it would have to withstand the core would likely crack if not overheat and become molten, losing it's function as another source of luminescence or electrical current. An interesting way around this would be to make several smaller stellar bodies that orbit each other... but this might 'diffuse' the light too much. However, using the small crystals (and 'small' here could mean quite massive) in suspension could prove quite fruitful. 1 cm3 of quartz, for example, produces 12,500 Volts when placed under 2 kN of correctly applied force. Much more exotic crystalline structures may exist in the future. A quick glance online reveals great candidates, such as [lead magnesium niobate–lead titanate](http://www.sigmaaldrich.com/technical-documents/articles/chemfiles/piezoelectric-crystals.html). I'm a philosophy major, so the maths is really difficult for me (read: impossible without much more time and practice). However, a cursory glance around Google shows that even at perfect energy reclamation levels only 10% of the gravitational force will be converted into useful energy. But this is likely to be nearer to 1%. This is purely based on [the piezoelectric effect](http://www.piezo.com/tech3faq.html). Essentially, what I'm making is a giant gravity fed electrical device that could be used to power some kind of super large LED? It's a space-lightbulb! It couldn't be perpetual, but I have no way of measuring how long it would last. Perhaps the crystals will eventually dissolve or be crushed into dust and float away into space? Perhaps the two liquids will eventually reach some sort of equilibrium? Perhaps these materials can never exist? ([Although I'd never say never!](https://en.wikipedia.org/wiki/Pentaquark)) I do not believe it could lead to any catastrophic events, though. I can now give more than two references :) [Answer] **Note: This answer is not even close to being finished. I’m putting it out there as a sort of sanity-check, so I can get some input as to whether or not my idea is totally crazy or not. Links and more numbers will be coming.** --- **Introduction** When I wrote this question, I thought that the [Kelvin-Helmholtz mechanism](https://en.wikipedia.org/wiki/Kelvin%E2%80%93Helmholtz_mechanism) would not be a good solution to the problem. It’s simple to see that if a Sun-like body were to produce energy at the same rate as the Sun in this way, it would run out of energy after ~107 years. This is something that has caused me to discard other ideas as well, something I’ll call the timescale problem. I looked at using some form of accretion in various ways. I was already familiar with [Thorne-Żytkow Objects (TŻOs)](https://en.wikipedia.org/wiki/Thorne%E2%80%93%C5%BBytkow_object), which had been suggested by a couple people. A TŻO is an M-type red giant or red supergiant that has had its core replaced by a neutron star. Nuclear fusion continues in the upper layers of the star, while the inner envelope is accreted by the new core, producing energy. Demetri’s answer talked about several pros and cons that are quite important. Unfortunately, the disadvantages (which I have added to) outweigh the advantages (see [Thorne & Żytkow (1977)](http://articles.adsabs.harvard.edu/cgi-bin/nph-iarticle_query?1977ApJ...212..832T&data_type=PDF_HIGH&whole_paper=YES&type=PRINTER&filetype=.pdf)): * Nuclear fusion still happens in the upper layers. * The envelope will last for a time on the order of ~107 or ~108 years, which is too short. * There is the potential for instabilities in various layers of the envelope. Another possibility that crossed my mind was to use a [quasistar](https://en.wikipedia.org/wiki/Quasi-star), essentially an extremely massive protostar whose core collapses into a black hole. The disadvantages are that the lifetime of the envelope would be about the same as that of a TŻO, and the protostar would have to be at least 1,000 times the mass of the Sun (see [Begelman et al. (2008)](http://mnras.oxfordjournals.org/content/387/4/1649.full.pdf)). One final speculative option I came up with was also mentioned: a [dark star](https://en.wikipedia.org/wiki/Dark_star_(dark_matter)). This would be a mixture of dark matter and normal matter that generates energy via annihilation between neutralinos. The downsides are twofold: The “star” would have a diameter between 4 AU and 2,000 AU, and would not emit light in the visible portion of the spectrum. These are the most well-studied types of exotic stars. It should be apparent that these could not be good substitutes for a star and conform to the time and luminosity requirements I set down. The solution I present here is far more mundane, at least in terms of the star’s composition. I propose using the Kelvin-Helmholtz mechanism to power a star like a [T Tauri star](https://en.wikipedia.org/wiki/T_Tauri_star). The timescale problem can be solved by periodic mass loss and replenishment recurring every Kelvin-Helmholtz time, by way of a disk in and out of which the tar oscillates. Nuclear fusion will not happen because temperatures in the core of the star will not have reached high enough levels. --- **1. The star** The Kelvin-Helmholtz mechanism transfers gravitational potential energy into radiated energy. The derivation is simple. The total radiated gravitational potential energy is $$U\_r=\frac{3M^2G}{10R}$$ or, setting $C=\frac{3}{10}$, $$U\_r=\frac{CM^2G}{R}$$ I use $C$1 [Footnote: Some authors use $\eta$.] here because this is not quite correct. The proportionality is correct, but there needs to be an indicator of how well the object compresses. This can vary greatly; for example, for Jupiter, $C\approx0.03$. In the present case, however, we will take $C=\frac{3}{10}$. Given that luminosity is energy over time, we can write $$\frac{U\_r}{t}=L\to t=\frac{3M^2G}{10RL}$$ We might naively substitute in $L=L\_{\odot}$, the luminosity of the Sun, and do the same for the mass and radius, and calculate the Kelvin-Helmholtz timescale. But this will not give the correct time for a star of such mass and radius, for several reasons: * There is no reason for the given luminosity to be the luminosity produced by such a star. It would only tell us how long a body acting like the Sun but producing energy via the Kelvin-Helmholtz mechanism would last. * The radius of such a star will change over time as contraction goes on. The same should hold true for luminosity, in certain cases. To accurately come up with a model, we must look to some real cases of stars contracting like this. Such stars are pre-main-sequence stars, living on either the [Hayashi track](https://en.wikipedia.org/wiki/Hayashi_track) (for lower-mass stars) or the [Henyey track](https://en.wikipedia.org/wiki/Henyey_track) (for higher mass stars). Stars on the Hayashi track decrease in luminosity over time while retaining a constant temperature; stars on the Henyey track increase in temperature over time while retaining a constant luminosity. After a certain amount of time, they join the main sequence, as nuclear fusion sets in. [Kumar (1962)](http://articles.adsabs.harvard.edu/cgi-bin/nph-iarticle_query?1963ApJ...137.1126K&defaultprint=YES&filetype=.pdf) provides an alternate expression for the energy released by contraction (we keep an extra term, assuming non-zero initial and final radii, the importance of which will be explained later): $$t=\frac{GM^2}{28\pi\sigma T\_{\text{eff}}^4}\left(\frac{1}{R\_2^3}-\frac{1}{R\_1^3}\right)$$ Note that there is an extra term for the initial radius. This is in part because of a different derivation and in part because we need to assume a finite initial radius, unlike most models. The effective temperature of a star on the Hayashi track can easily be calculated: $$T\_{\text{eff}}=(2600\text{ K})\mu^{13/51}\left(\frac{M}{M\_{\odot}}\right)^{7/51}\left(\frac{L}{L\_{\odot}}\right)^{1/102}$$ where $\mu$ is the mean molecular weight of the gas particles. This last factor of luminosity shows that the temperature of a star on the Hayashi track is only very slightly luminosity-dependent. In this case, I’ll choose to drop that term entirely, setting it equal to 1. This means that if we set the final and initial radii constant, the time spent on the Hayashi track is entirely mass-dependent, with the exception of composition. We can say $$T\_{\text{eff}}^{-4}\approx(2600^{-4})\mu^{-52/51}\left(\frac{M}{M\_{\odot}}\right)^{-28/51}$$ and then $$t\approx\frac{(2600)^4G}{28\pi\sigma\mu^{52/51}}M^2\left(\frac{M}{M\_{\odot}}\right)^{-28/51}\left(\frac{1}{R\_2^3}-\frac{1}{R\_1^3}\right)$$ Now, I could simply set $t$ to ~109 years, then use that to find the mass of the star by picking two radii as guesses. But the big issue there is that low-mass, low-luminosity stars stay on the Hayashi track for longer. Therefore, any object that stayed on the Hayashi track would be pretty dim for much of that time. So this is pretty pointless. This is why it’s necessary for the star to go through cycles of contraction. In order for a star on the Hayashi track to have a high enough luminosity, it must have a certain mass. However, it’s time on the Hayashi track will not be long enough for my needs. Therefore, it must continue on this track in a circular evolutionary track. Each cycle begins with the gaining of a large circumstellar envelope of radius $R\_1$. Gravity forces the star to contract to a final radius of $R\_2$. At the end of this contraction, some mechanism must cause mass loss, so that succeeding envelopes do not become excessively big and cause the star to eventually begin hydrogen fusion. This mass loss will take away all but a small core. The star will then gain a new envelope, and the cycle repeats itself. The mass gain mechanism will be discussed further later on, but I will discuss the mass loss problem now. The most tempting option is to have a strong stellar wind blow away excess material. In fact, T Tauri stars often have strong stellar winds, sometimes called T Tauri winds, or bipolar outflows related to astrophysical jets. The problem here is that these winds only set in after nuclear fusion has begun. Another issue with that is that stellar winds are normally pretty regular. The type of mass loss I’m looking for would be sudden, violent, and short-lived. So at the moment, I’m in a bit of a bind as to what to do about that. I suspect disk-star interactions could end up stripping away the envelope and replacing it with a less dense one, but I’d need simulations to prove that. **2. The Disk** For the disk, I’m picturing something in the vein of an accretion disk. It will have to be dozens of solar masses in mass, and it will need to be quite wide. A better unit of measurement might be light-years, not AU. It will also have to be thick. For the density profile, I'm thinking of using a [Plummer-Kuzmin model](http://www.astro.washington.edu/users/ivezic/Astr509/lecture2.pdf) profile: $$\Phi(r,z)=-\frac{G\mathcal{M}\_{\text{disk}}}{\sqrt{r^2+(a+\sqrt{z^2+b^2})^2}}$$ where $\Phi(r,z)$ is gravitational potential and $a$ and $b$ are constants. The disk’s composition will be mostly dust and gas, in the form of molecular hydrogen (possibly non-ionized). It shouldn’t be too hot or dense - again, I need to prevent nuclear reactions from happening in the disk or during accretion. To analyze the motion of the star, in its [Sitnikov](http://www.scholarpedia.org/article/Sitnikov_problem)-style orbit, I’ll use a Lagrangian: $$\mathcal{L}=\frac{1}{2}M\dot{z}^2-M\Phi$$ I’ve restricted the motion to be linear in the $z$-axis, so our only relevant Euler-Lagrange equation is $$\frac{d}{dt}\left(\frac{\partial\mathcal{L}}{\partial\dot{z}}\right)=M\ddot{z}=\frac{\partial\mathcal{L}}{\partial z}$$ This then becomes $$\ddot{z}=\frac{G\mathcal{M}\_{\text{disk}}z\left(a+\sqrt{b^2+z^2}\right)}{\sqrt{b^2+z^2}\left(\left(a+\sqrt{b^2+z^2}\right)^2+r^2\right)^{3/2}}$$ The star will begin at $r=0$, and, given that there will be radial symmetry and no radial forces, it will stay there. Therefore, $$\ddot{z}=\frac{G\mathcal{M}\_{\text{disk}}z\left(a+\sqrt{b^2+z^2}\right)}{\sqrt{b^2+z^2}\left(a+\sqrt{b^2+z^2}\right)^3}=\frac{GMz}{\sqrt{b^2+z^2}\left(a+\sqrt{b^2+z^2}\right)^2}$$ This is a second order nonlinear differential equation of the form $$y''=f(y)$$ where $y=g(x)$. Here, $y=z$ and $x=t$. We can solve for $t$ as a function of $z$. [The solution is](http://eqworld.ipmnet.ru/en/solutions/ode/ode0301.pdf) $$t=\pm\left(-C\_2+\int\left[C\_1+2\int f(z)dz\right]^{-1/2}dz\right)$$ Integrating $f(z)$ doesn't appear to be possible analytically, though I'm trying numerically. One (inelegant) way you could do it would be to approximate the Taylor series of $f(z)$ up to some $O(z^N)$ for sufficiently large $N$. Then you could integrate that, then maybe take the expression inside the brackets and create a Taylor series for *that*, and integrate. The upside of all this is that if you know the velocity of the star at $z=0$, you can find its maximum height (use conservation of energy), and from that you can find its period, $P$, and $P/2$. My main worry with this setup is stability. A Sitnikov planet is unstable against radial perturbations. Depending on the density profile of the disk, this may or may not be the case. Now, the case of a ring-like object providing the potential for the body to oscillate in may not have such instabilities. [This page](http://www.aleph.se/andart/archives/2014/02/torusearth.html) explores some of the properties of a toroidal planet, including possible orbits for its moons. Believe it or not, there are stable (at least in the short-term) orbits that run through the center of the torus! [](https://i.stack.imgur.com/CUUwOm.png) I'd say it's possible for the same kind of stability to be possible here, even if the hyperboloid is "straighter". We can decompose the density profile of the disk into such a torus, at some stable distance from the center, and a less dense region involved in the active accretion. This could lead to orbits similar to those computer for the moon and the toroidal planet. [Answer] I'll be editing, cleaning this up, and fleshing it out more later (and replacing the wikipedia links) but wanted to put down what I have for now before I forget or lose all the pages. We can have a **Artificial Star** with a [diamond core](https://worldbuilding.stackexchange.com/questions/11827/how-large-could-a-planetary-diamond-be/11830#11830), heated by an antimatter reaction engine to 3,000 C. That's not quite enough for a star like our sun, but it can heat the surrounding hydrogen enough to get into the red/orange range. Based on Samuel's excellent answer [here](https://worldbuilding.stackexchange.com/questions/11827/how-large-could-a-planetary-diamond-be/11830#11830), we can have a stellar-sized diamond in the 253,000km and 573,000km range. That's larger than a solar core, which means that we can surround it with hydrogen and keep it from triggering fusion. Diamond conducts heat well, and can be heated safely up to ~[3,000 C](https://en.wikipedia.org/wiki/Material_properties_of_diamond#Thermal_conductivity) when under pressure. Like when it's in the center of a star. 3,000 C is right around the [surface temperature of a red giant](https://en.wikipedia.org/wiki/Red_giant#Characteristics), so we can get that kind of light. TODOs: * Determine if the mass of the stellar diamond is greater than the mass of the core, and if so if it's enough more to trigger fusion. * Figure out how to keep the antimatter engine from being destroyed by pressure, ruining the entire thing. [Answer] ## Nope. You'll get a star sized object [releasing energy via fusion unless it's made of elements heavier than iron](http://iopscience.iop.org/0004-637X/576/1/323/pdf/0004-637X_576_1_323.pdf). So you can make a [star from iron](http://abyss.uoregon.edu/~js/ast122/lectures/lec18.html), but it won't release much energy. **What about fission?** Unfortunately getting too many fission products together without a [neutron moderator](https://en.wikipedia.org/wiki/Neutron_moderator) will release more energy than the gravitational binding energy of the star and it will blow itself apart. All the good neutron moderators are lighter than iron, so getting a star's mass of them together will simply cause them to undergo fusion. There are some [self-limiting nuclear fuels](http://www.iaea.org/inis/collection/NCLCollectionStore/_Public/37/088/37088511.pdf), like uranium zirconium hydride, which has a negative fuel temperature coefficient of reactivity, but I doubt you could create a star made of it and maintain those properties. Any other reaction will not prevent fusion or will not last long enough to be near the same lifetime as a traditional star. [Answer] [Thorne–Żytkow objects](https://en.wikipedia.org/wiki/Thorne%E2%80%93%C5%BBytkow_object) are an example, if they exist (and there is evidence that they do). These stars can have two different power sources: * Nuclear fusion, albeit under rather unusual conditions. * Accretion onto the NS core. The second is much more efficient (energy output ~$0.12mc^2$ vs ~$0.007mc^2$). The primary source of power for an actual TZO may be either, however. This is because the convective envelope can bring down new fusion fuel and sweep away the fusion ash. Since accretion onto an NS releases much more energy per unit mass than fusion does, it is fully capable of supporting the TZO against gravity for as long as the TZO exists, even if fusion is not the primary source of energy. Lifetime is likely to be rather short (< 1 million years). However, this is because stellar winds eject the outer envelope, not because accretion cannot provide enough power. While fusion will occur in any TZO, in an accretion-driven TZO the amount of energy from fusion is much lower. [Answer] It's hard to conceive of a star that *doesn't* supply itself by nuclear fusion, **except those that already exist**. # Some background Nuclear fusion is a process by which two nuclei of two atoms fuse together (hence *nuclear fusion*). **It can only happen under immense temperature and pressure.** A star is a *huge* object. At its core, the pressure and temperature *are* immense, and nuclear fusion will start happening because of this. # Some numbers [$$ \begin{equation}\tag{1} T\_{\text{eff}} \propto \sqrt{M} \end{equation} $$](https://books.google.co.uk/books?id=LEe3BAAAQBAJ&pg=PA17&lpg=PA17&dq=temperature+of+10m+star&source=bl&ots=c-VJvoPq41&sig=i4QVp1nJ7PE5kh8lP9blXNh_W-U&hl=en&sa=X&ved=0CCMQ6AEwAGoVChMIx-D6gO6wxwIVAloUCh3j_QAE#v=onepage&q=temperature%20of%2010m%20star&f=false) Using [$T\_{\text{eff ☉}} = 5780\text{K}$](http://www.wolframalpha.com/input/?i=sun+effective+temp) and [$M\_☉ = 1.988 \times 10^{30} \text{kg}$](http://www.wolframalpha.com/input/?i=sun+mass), from (1) we get: $$ T\_{\text{eff}} = k\sqrt{M} $$ $$ k = \frac{T\_{\text{eff}}}{\sqrt{M}} $$ $$ \begin{equation}\tag{2} k = 4.1 \times 10^{-12} \end{equation} $$ We know that [objects as "small" as 3 Jupiter masses are stars](https://en.wikipedia.org/wiki/List_of_least_massive_stars), though fusion only occurs [from 13 Jupiter masses](https://en.wikipedia.org/wiki/Neutron_star) (that'll be relevant in a moment). Thus, of the vast uncountable trillions of stars, anything over $ 2.47 \times 10^{28} \text{kg} $ *will* undergo nuclear fusion. Using our numbers from (2), that's: $$ T\_{\text{eff}} = 4.1 \times 10^{-12} \times \sqrt{2.47 \times 10^{28}} $$ $$ \approx 644 \text{K} = 371 \text{°C} $$ which is a *teeny-tiny* temperature, in stellar terms. Of course, their cores are hotter, and that's why the fusion occurs, but their effective temperature is tiny. Thus, the *vast majority* of stars are hotter. # Conclusion **The majority** of stars will power themselves by nuclear fusion. Whether other methods are possible is slightly irrelevant, because those methods' existence will not deny the fact that due to the *immense* amount of energy released in fusion, nuclear fusion happening will be the primary power source of a star. Excluding, perhaps, inherent black holes. **The minority** of stars - and these stars [**already exist**](https://en.wikipedia.org/wiki/Neutron_star) - will exist without being powered by nuclear fusion. Neutron stars, while still categorised as stars, don't undergo fusion. [Answer] In [*Palimpsest*](https://en.wikipedia.org/wiki/Palimpsest_(novella)), Stross uses a "necrostar" to keep the earth habitable for orders of magnitude longer than the sun would last. This was a black hole surrounded by gas, gravity being the ultimate energy source, giving nearly 100% mass to energy. The whole reason for replacing the sun was to make it last (much) longer. [Answer] ## Theoretically possible, I think. Using our friend thorium. Here on earth, Th is essentially 100% Th-232 so let's consider it pure. Th is not fissile (good for our purposes), and it does have a nice long-lasting 14.05 billion year half-life. If you consider the entire thorium series, you have 42.6 MeV of energy output (including neutrinos) which is also 6.83e-12 joules. Of course, we lose the nearly all of the neutrino heat (just as we do for our sun). One mole of Th thus eventually yields 4.11e12 J, or one kg yields 1.77e13 J. Half is released in the first 14 billion years. One kg of Th-232 thus releases about 20 mWatts, so you need 5 tonnes to power a 100 watt bulb. Congratulations, you now have a very low power, but very long lasting RTG. Our sun has a mass of about 2e30 kg. So let's replace it with 2e30 kg of thorium. We now have a 4E28 W RTG. Our sun actually produces only about 4E26 watts, so this is 100 times as powerful as our sun, and it should be considerably smaller too considering the relative density of the materials. The actual amount of Th-232 you need to make your own fusionless sun will depend upon the exact conditions you want, but as a first approximation, a mere 1e28 kg of Th should be close enough as the total power output will be about the same as our sun. Making this star is easy. Step 1: Start with 1e28 kg of Th, Step 2: throw it all into a big pile and stand way back. Finding that much thorium will not be easy. Mass of universe is about 3e52 kg, Th is perhaps 1 part in 1e13, so rounding to nearest power of 10, 1e39 kg of Th in the universe. This is enough to build 1e11 thorium stars. Hmmm, maybe not so hard after all if you are sufficiently motivated to scavenge a galaxy for all of its thorium. If you find that as time passes the star is no longer as shiny as you like, toss a little more thorium on the fire every 10 million years or so. Are we done? Not fusion powered. Power output similar to a star. Lifespan similar to a star. No disasters in the next few billion years. [Answer] An accretion disk, fed by a brown dwarf or gas giant planet. * Not a star (although the central body would usually be a stellar remnant; a white dwarf, neutron star or small black hole) * Supported against gravity by angular momentum * Produces energy by converting the gravitational potential energy of infalling matter into radiation. For the white dwarf and neutron star central body, radiation is emitted when the infalling matter collides with the surface; there is additional energy release from fusion at this stage. If the central body is a black hole, there is no surface to collide with but the event horizon has such a small circumference (Schwarzschild radius of a Sol-mass black hole is 2953m) that frictional heating of infalling matter causes it to radiate away almost all of its gravitational potential energy. If this is an engineered structure, multiple gas giants could be kept in reserve; such a structure could last for trillions of years. [Answer] A massive object doesn't *necessarily* collapse due to gravity. Gravity will certainly pull the component part(icle)s together, but it can't hold them there. With gravity alone, each part would be in *orbit*; converting between kinetic energy and gravitational potential energy forever. If we introduce another force, like electromagnetism, then two things happen. Firstly, energy can be converted in new ways; for example, particles can emit electromagnetic radiation, and hence decrease their kinetic + potential energy, causing their orbits to decay. Secondly, new interactions between particles can occur, ie. collisions, which disrupt their orbits. That's why Hydrogen clouds collapse into a disc. What if we *don't* have a force like electromagnetism acting on our particles? This is the case in some models of dark matter. In these models, dark matter interacts via gravity but not via electromagnetism, so it would not collapse in the way that baryonic matter does. A collection of perpetually-orbiting dark matter particles is called a [dark matter halo](https://en.wikipedia.org/wiki/Dark_matter_halo). Whilst normally discussed on galactic scales, in principle such a halo could have the size and mass of a star; especially if they're engineered that way. So, dark matter halos don't need an energy source to avoid gravitational collapse; but they're not very "star-like". Is there a way they could emit energy like a star? [WIMP](https://en.wikipedia.org/wiki/Weakly_interacting_massive_particles) models allow dark matter particles to interact via a/the weak force; in this scenario, collisions can occur, just very rarely. Many experiments are attempting to detect such collisions. These rare collisions provide a mechanism for regulating some other reaction, eg. matter/antimatter annihilation, to prevent the normal run-away chain-reactions mentioned in [other answers](https://worldbuilding.stackexchange.com/a/22778/2467) [Answer] Brown dwarfs are star-like objects, which get a lot of their energy from gravitational collapse. If you imagine a brown dwarf without any Deuterium (also without any Lithium if the brown dwarf massive enough to fuse Lithium), then the entire energy output comes from gravitational collapse, plus radioactive decay of whatever radioactive elements. This would be dim and quite quickly cooling object, but still star-like without any fusion. To increase lifetime, add radioactive elements with long half life, for example [Thorium-232 has half-life of 14.05 *billion* years](https://en.wikipedia.org/wiki/Thorium#Isotopes), so enough of it should keep things warm for quite a while, without causing chain reaction. If you want natural mechanism to produce a "star" like this, then you probably need to get inventive, but it could be "easily" constructed by any [Kardashev Type 3 civilization](https://en.wikipedia.org/wiki/Kardashev_scale#Definition). Another, more exotic object would be a neutron star or a white dwarf surrounded by stable accretion disk, which would lose matter in with a stable rate. To prevent fusion of the infalling matter, it would have to be composed of heavy enough elements, so that they will not undergo fusion as they collide with the neutron star. This kind of object would probably need to be made, at least if it needs to be long-lived and have a relatively stable energy output. The upper limit for lifetime is probably until the neutron star collapses into a black hole, so depends on desired energy output, determined by mass flow of the infalling matter. You might have to add some extra objects to destabilize the disk of material just right to keep things falling in at a desired rate. You could also imagine a black hole with such an accretion disk, but then there will be no actual collision with the central object, so you would have to have so much infalling matter, that it will collide with itself and heat up that way. Without doing any maths, I think this kind of object would be quite short lived, before it would run out of infalling matter. Another exotic options might be black hole and/or neutron star in a binary system, where you might be able to have controlled rate of matter falling in and generating energy for longer, than a single neutron star could do (before collapsing into a black hole). [Answer] Can a question also be an answer? Because I don't have the physics to answer this and am not sure anyone does. A magnetic field has an energy density. One of the most exotic known astrophysical objects actually observed is the **magnetar**. It's a neutron star that formed with a magnetic field of up to 10E11 Tesla. Its energy output for tens of thousands of years is released by the decay of that magnetic field. For comparison the greatest magnetic field created on Earth is around a hundred Tesla. The field around a magnetar will distort atomic nuclei into threadlike formations. It will cause a vacuum to become birefringent. Some observations of magnetars ( glitches and anti-glitches) are not well understood. The energy stored by a given volume of magnetic field goes as the square of that field. My question. Other than the gravitational collapse of a high enough density of energy into a black hole, is there any upper limit on a magnetic field's strength? If not, then a "super-magnetar" provides a physical alternative to nuclear fusion for a source of stellar quantities of energy over stellar amounts of time. What form it might take and how it might arise, I cannot begin to imagine. If you want to stray from hard science to handwavium then is there a new form of matter to be found closer to the black hole limit? And might it be capable of technological manipulation? [Answer] No idea on the natural one. But I am assuming there is some value in providing an artificial solution. And that the hard science tag applies to the main question. (ie, I won't do the numbers for a side question.) Assume you have a starless Earth size and composition planet you wish to provide with an artificial sun that would look convincingly sun-like for a pre-industrial civilization you wish to plant on the planet. Further assume the planet also has a moon identical to ours. Or at least reasonably similar. By coincidence Sun and Moon are roughly the same size from Earth. Thus if you heat the surface of the moon to same temperature as the photosphere of the Sun. It will be reasonably "Sun-like" and provide the same amount of light and energy. The spectrum, among other things, will be different, so a civilization with industrial technology and any astronomical knowledge will not confuse it with a real star. The important thing is that Moon is much smaller than any kind of stellar object. And it can be smaller than Moon if you make the orbit smaller. This means that much less energy is needed and much less of the power will be wasted on irradiating empty space. For example, if the moon is tidally locked, only the surface of the planet facing side needs to be heated to full temperature. These factors lower the energy and power needed enough for radioactive decay to be a viable method for providing it. **IF** we also assume that your artificial sun only needs to work a million years or so. I doubt that the several billion years needed for natural evolution are possible. For an ark type scheme you might be able to get away with a lifetime of a hundred or even ten thousand years. Lifetime here means that the power hasn't been reduced noticeably. Only heating the surface helps here a lot since the rest of the moon acts as a heat sink reducing output at the beginning. Only real issue is gathering the required amount of radioactive material. I can't really think a solution other than using nuclear explosions to irradiate (and pre-heat) the surface. And fusion devices would probably be needed to avoid a shortage of fissile materials. A civilization that actually does artificial suns for starless planets might have a better solution though. For example, a fission powered particle accelerator might be able to irradiate the surface since less of energy would be wasted on light and kinetics (explosions). Although with underground explosions of proper yield the waste should be minimal. ]

[Question] [ > > Stark: What's the vibranium for? > > > Ultron: I'm glad you asked that, because I wanted to take this time to explain my evil plan... > > > - *Avengers: Age of Ultron* > > > A pervasive trope throughout literature, television, and film is that the Big Bad Supervillain must *always* take several minutes to explain their Super Evil Plan to Rule the Country/World/Tristate Area to the hero, usually when he has the hero in his power. This begs the question, **why would a supervillain want to do this?** After all, most supervillains are portrayed as [Chessmasters](https://tvtropes.org/pmwiki/pmwiki.php/Main/TheChessmaster) or [Clock Kings](https://tvtropes.org/pmwiki/pmwiki.php/Main/ClockKing), whose plans can't adapt to changing circumstances very well. I am going to be using the information from these answers in a satirical work, so I would prefer answers that involve [Insane Troll Logic](https://tvtropes.org/pmwiki/pmwiki.php/Main/InsaneTrollLogic). That being said, normal logic is still quite acceptable. --- **Edit:** I am asking for a (semi) logical explanation for a *general phenomenon* among supervillains *as a species*. This falls under the category of "system-wide rules", which are on-topic according to [this meta post.](https://worldbuilding.meta.stackexchange.com/a/6839/70058) [Answer] You wanted Insane Troll Logic, so here it is. Heroes are good right? and good people like to correct other peoples mistakes, therefore, if you tell your hero your plan and there's anything wrong with it, he'll tell you what it is so you can correct it. The crazy thing is, this may just work, at least for movie logic. Say your villain doesn't have a flawless plan to conquer/destroy/gobsmackle the country/world/tristate area. I mean, those would be pretty hard, and a lot of powerful, smart and resourceful heroes would probably oppose you. But what he does have is perhaps an approximation of what this plan would look like. And, a handful of other plans to partially beat, trap or temporarily disable some of the previously said heroes (individually). Then, the villain monologues, he tells the trapped hero his plan. Now, one of two things will occur, either the hero will try to escape your trap to foil your plan or s/he'll smugly tell you your plan would never work, because.... (and here's where you take notes). **Ultraman**: "So your plan is to use a gigantic lasso to pull the Moon towards the Earth, ha, that would never work, you'd need some sort of oversized tractor beam for that" **RaccoonMan**: "HA, your tractor beam is impressive, but you'd need a power source no short of a fusion reactor to even make the Moon flinch" **Ms. Amazing**: "Pff, nice fusion reactor you've got there, shame it will overheat and melt your whole plans away, you'd need to move the whole thing to Antarctica to stand a chance" **HumanFireplace**: "Good luck with all the penguins not pecking at your electronics" **RedTailed Hawk**: "Wait, so you got the penguin repellant??? ... I need to get out of this cell" Now you only need to beat the last hero to win. But, hey, this is what you have been planing for. I mean all the other planning was basically outsourced for you. You just need to interfere with one hero long enough for your plan to work. Most other villains probably fail cause they are worrying about two things at once. How to carry out their evil plan and how to stop the heroes from messing them up. You need only case about the latter. That means having at least twice the brainpower at your disposal. [Answer] **Because it feels so good** Gloating, when you get down to it, is really the ultimate display of superiority. It's essentially telling the hero 'I'm so confident in my plan that I can tell you all of it and there's *nothing* you can do to stop me!' While I suppose you can take a leaf out of Watchmen and follow up the evil plan gloating with 'Oh, by the way this all happened half an hour ago so you *literally* can't stop me', that's just not as satisfying. The most satisfying thing is telling the hero *in advance* and then watching their pathetic, weak, futile struggle against the inevitable success of your evil scheme. Because what’s the point of being a villain if you can't rub it into people's faces and enjoy their salty tears of despair? Is it kind of dumb? Yeah. But the temptation is really there, and villains generally don't get to where they are by ignoring their temptations - generally, the opposite, if anything. [Answer] > > Something Vimes had learned as a young guard drifted up from memory. If you have to look along the shaft of an arrow from the wrong end, if a man has you entirely at his mercy, then hope like hell that man is an evil man. Because the evil like power, power over people, and they want to see you in fear. They want you to know you're going to die. So they'll talk. They'll gloat. > > > They'll watch you squirm. They'll put off the moment of murder like another man will put off a good cigar. > > > So hope like hell your captor is an evil man. A good man will kill you with hardly a word. > > > ― Terry Pratchett, Men at Arms [Answer] As Gul Dukat says, "A true victory is to make your enemy see they were wrong to oppose you in the first place. To force them to acknowledge your greatness." How are they supposed to appreciate how right you are and how wrong they are if they don't know what you're doing in excrutiating detail?? [Answer] # **Everyone, Deep Down, Believes they are the Good Guy:** Good people want others to acknowledge that they are good, right? Well, if you don't understand why I've rigged these children to a bomb, then I merely look like a bad guy! I want to kill half of all life not because I'm evil, but because it's the right thing. And revenge is reasonable - you've seen the movies, but not knowing how your father stole my father's secret formula makes me look *petty*. The ends justify the means, but somehow people need to know why the means were justified. [Answer] Most of the villains I am aware of became villain as a reaction to the lack of acknowledgement they have experienced at some time during their life. They seek to rule to world not just because they crave power, but because they crave recognition. And what is more rewarding that have the non plus ultra of mankind, the brave super hero, stare at you in awe while listening at the wonderful convolutions of your evil plan? Puny weak humans just flee your presence, only super heroes stand your presence and your mind. [Answer] This is addressed in the following way mechanically in the *Marvel Super Heroes Role-Playing Game* (1984, Campaign Book, p. 33), in the words of Doctor Doom: > > While heroes often stand in the path to triumph, they also represent > the small portion of humanity that understands and appreciates the > achievements of marvelous thinkers like me. It is uplifting and > satisfying to explain how I achieved triumph to a person with a mind > capable of understanding the fine details of the plan, even if the > listener is a bitter foe. > > > Explaining the vital points of a plan or device to a hero earns a > bonus of 20 Karma points. Of course, only fools would do such a thing > unless the hero were powerless to interfere. > > > [Answer] ## People are social animals. People like to tell stories. This really isn't far fetched at all. It's gotten a bad rap because it's *hackneyed* and *cliched*, not because it's unrealistic. (Unrealistic doesn't seem to bother people anyway; witness people getting blown away by gunshots in the movies.) [Here](https://www.youtube.com/watch?v=d-7o9xYp7eE) is a great example. The whole video is well worth a watch, but the relevant part starts at 26:30 or so. Police are exceedingly good at getting confessions out of folks. Just listen to him talk. Hell, *the first words out of his mouth* elicit a confession from an audience member, after 25 minutes of a lawyer lecturing *literally about why you should never talk to the police*. He starts off by asking people who drove to the lecture today, and then he asks if anyone maybe drove a little fast to get there. And someone raises their hand! The police officer goes on to elaborate that getting people to talk is easy, because people hate silence and all you have to do a lot of the time is just sit there, in total silence, and fill out paperwork. A lot of folks will feel compelled to start a conversation. Which is their doom. And they know that, *and they do it anyway*. [Answer] Since the question is tagged "psychology", here's the proper psychology term for this: Narcissistic Personality Disorder (NPD) <https://en.wikipedia.org/wiki/Narcissistic_personality_disorder> On top of this, gloating super-villains who literally feel **compelled** to explain **in great details** their evil schemes (despite the fact it's super counter productive) may also suffer from: Obsessive Compulsive Disorder (OCD) <https://en.wikipedia.org/wiki/Obsessive%E2%80%93compulsive_disorder> and/or (mild) Autism Spectrum Condition (ASC) <https://en.wikipedia.org/wiki/Asperger_syndrome> (it's not unusual for people with Asperger's/mild ASC to talk very enthusiastically and in great details about their very specific interests, in a somewhat overwhelming fashion, leaving their audience slightly bemused) Note: I am only providing pointers for information (and possibly further research). Mental health conditions should be dealt with sensitively in fiction. In the real world: (from what I understand) * NPD is rather strongly correlated with abusive behaviour towards others * ASC is more likely to be at the receiving end of abusive behaviour * OCD is mostly directed inwards, but the anxiety can "spill out" and turn into aggression In fiction, I believe (this is subjective...) that gloating supervillains are typically meant to be narcissists. Whereas the rambling, quirky-yet-likable scientist side-kick who comes up with all the hero's super-gadgets is more reminiscent of ASC. [Answer] You're a villain. You've been planning and plotting and pushing pieces around for literally years behind the scenes. You've put in the work. You have minions, but they're well invested in your project, they know the working that you've put in and were onboard from the start. (and anyway they're employees, not comrades) You've not really had anyone you can talk to about this project you've been dedicating your life to for years. You can't exactly strike up a conversation with someone in a coffee shop and say "oh yeah, I've been working on my plan to rule the world...let me tell you all about it" Either they take it seriously, and you've shot yourself in the proverbial foot, or they don't, and while you've been talking they haven't believed you. So finally, you're in the endgame, and you've got someone "on the outside" in front of you. Someone to talk to without the pretence or as an employer. Someone who'll take you seriously. Your intellectual solitary confinement is over. Of course you talk about your evil plan! [Answer] It is taught in "Evil Boarding School of Villainy for Criminally Insane Children" in at least two subjects every semester. And continued to be taught in "Highschool of Evil" and "College for questionable science and evil experimentation". "Taught" would be an understatement. Beaten into them would be closer to truth. Because there are only bad people, only some of them are on opposing sides. The villain who is the owner of the school actually doesn't like competition and wants "Heroes" to stop his proteges. He himself never monologues to hero and is the deadliest villain on the planet. <https://www.youtube.com/watch?v=BjKpqKLZZAc> And unless you want all heroes and villains to gang up on you because you are unlicensed upstart trying to be supervillain, you will get licensed and certified at one of the institutions mentioned above. Or one of their competitors. Besides, what's the difference between supervillain and regular villainous scum? Presentation! <https://www.youtube.com/watch?v=k7xy7gFH0lI> And monologuing is part of the "Presentation package" brainwashed into any aspiring villain. [Answer] ## Science Related Memetic Disorder (SRMD) [SRMD](https://www.project-apollo.net/mos/index.html), often referred to as Mad Scientist's Disease, is a [well documented](https://tvtropes.org/pmwiki/pmwiki.php/Main/ScienceRelatedMemeticDisorder) mental disorder. It is memetic, meaning it develops from contagious ideas rather than biological organisms. There are five [clearly defined](https://en.wikipedia.org/wiki/A_Miracle_of_Science#Mad_Science) stages that mad scientists pass through: 1. **Infection.** An idea for world domination occurs to the scientist. 2. **Obsession.** The scientist works obsessively towards his or her goal. 3. **Challenge.** The forces of law and order confront the scientist. 4. **Chase scene.** Self-explanatory. 5. **Denouement.** The scientist surrenders, sometimes after a brief fight and/or negotiation. If SRMD is not caught in the early stages, it may not be treatable without completing all five. Without treatment, the cycle will repeat ad nauseam. As documented in [A Miracle of Science](https://www.project-apollo.net/mos/index.html), if a mad scientist does not reveal their plot, they cannot complete the cycle and begin recovery. Unfortunately, this is also often how the disease spreads. [Answer] **The evil plan was not the real goal, beating the hero was.** The villain's goal was never to destroy the world, the villain's goal was to beat the hero (why? Is it his brother? Did his father try to force unattainable hero skills on him? Did his girlfriend leave him for a hero?). If the hero will simply say "You've beaten me," the villain has won and will stop his plan. But as long as the hero refuses to yield, then the plan must continue to prove he has beaten the hero. [Answer] # 'Insane Troll Logic' Answer * Supervillains are called that because they live in super villas. * Aston Martins are super cars. * Divide by the numerator, and you get Aston Villa * Aston Villa was founded in 1874 * 1874 is leet-speak for IBTA, the International Baton Twirling Association * A baton is the traditionally sign of a field marshal * Field Marshals always tell their enemies how they will keep to the rules of war * This is, obviously, why supervillains must always announce their plans to their adversaries. [Answer] ## The hero arrived to early The villian is just waiting for the next stage of his plan to go into place when the hero arrives. To stall for time he brags about the details of the plan so far in order to distract and buy those last few minutes of time. [Answer] Assuming that your super villain isn't from Andromeda IV, where everyone breaths methane, the villain is human. Human beings crave social interaction and attention. Go look at all the stupid bullshit people post on twitter everyday. They are bragging, boasting, and trying to get attention. If Super villains were properly updated to modern times, they would all have social media accounts and would be ranting to the largest audience they could get. The other aspect about SV to consider is that they are essentially terrorists. A terrorist is someone who is disenfranchised from participating in a political system. A terrorist blows up a bus of civilians, because they have no other route to get attention or enact the change they want other than to commit atrocities. You might have some petty criminals who just want to get rich, or psychopaths who want to kill people for the joy of killing, but most comic-book style SV are just terrorists in spandex. So once you have a captive audience (haha), of course you will tell them why you are crashing the moon into the earth. The act is an attempt to get attention, and now you have it. [Answer] The villain wants the hero to come over to his side. He believes that once he explains the plan, the hero will be so impressed by its genius, that he will join the villain in his quest of evil! **or** The hero has promised that if the villain only explains his plan, he will not interfere with it. The villain, believing that since the hero is "good" he must be honest, takes him at his word. [Answer] You could say it's ego. They want to say "hey, look how I outsmarted the hero with this brilliant plan" but in reality it's just a plot device. [Answer] Naturally occurring mind control fungus. Villains are just normal people who were living their normal lives when they fell victim to a strain of [Ophiocordyceps](https://en.wikipedia.org/wiki/Ophiocordyceps_unilateralis) The fungus takes over the mind of the villain filling them with some 'master plan' or another and driving them to work towards this plan. There is always a fatal flaw in the plan (the fungus doesn't actually want the world to be destroyed after all. It only wants to spread to a new host.) And there is always a moment when a hero and hopefully a number of hostages are captured and loosely restrained. Eventually, the plan consumes the mind of the villain until it is the ONLY thing on the villain's mind. It is at this point that the monologuing begins. The villain can't help but explain the details of the plan once the fungus has reached this stage. This is the vital moment for the fungus. The moment when it releases microscopic spores from the mouth of the villain directed towards the restrained hero and hostages, allowing it to spread and reproduce. Once the monologuing has finished, the villain has served its purpose and is no longer under the influence of the fungus. This is why many villains have a moment of repentance: "What have I done?!" It is also important that the hero and hostages can be saved and can foil the plan. At least one of those exposed to the spores is likely to become a new host for the fungus and eventually continue the reproductive cycle of the monologuing fungus in the amazing sequel. [Answer] Because the deed is ***already done*** and the rest is an automaton. Nothing can stop the plan now, so why not gloat a little and inform the self-proclaimed hero that he is too late? But **only** if there isn't even a need to kill the guy anymore because every [competent mastermind knowing his list](https://tvtropes.org/pmwiki/pmwiki.php/Main/EvilOverlordList) should just kill them if there might be any reason for that (*especially* Points 4, 6, 7, 16, 142). Note that a good doomsday device is simple (Point 85) and has no self destruct (Point 9), meaning that even the heroes entering the lair could be the moment the deed is done and our mastermind just starts to elaborate what now happens and **nobody** can stop it now... Let's ask the greatest of all masterminds how it's done: > > My name is Ozymandias, king of kings: Look on my works, ye Mighty, and despair! > > > eh, wrong Ozymandias. This one: [](https://i.stack.imgur.com/igP95.jpg) Alternatively, the countdown of the doomsday clock is a little off and the mastermind ensures his adversary believes he still has time (Point 15)... [Answer] Well, they get paid per the word, just like the author that wrote their story. Because they are the **villain**, and villains get very little speech time. As they are being paid by the word, they would obviously squeeze every extra word into the very few speeches that they are allowed. Thus the Villain will *always* elaborate and expound upon their final confrontation with the Hero. The Villain is also excessively verbose and florid upon their first introduction.. I mean ***really!***, just what random mugger/murderer/psychopath hangs around to spout "*Have you ever danced with the devil in the pale moonlight? I ask that of all my prey. I just like the sound of it.*". I mean c'mon! That's just milking the speech budget for ever cent you can! (Yes, this explanation breaks the fourth wall. It stomps on the bits while sneering at the universe. Which is quite in-character for most villains) [Answer] (Warning: 2 of 3 links ahead are to TV Tropes.) Maybe they don't *want* to do any such thing. Maybe the universe runs on tropes, literally, and they are *compelled* to do so by irresistible forces (which, conveniently, also compel the hero to listen to the speech without [interrupting the villain](https://tvtropes.org/pmwiki/pmwiki.php/Main/CombatPragmatist)). This can cut both ways, with the heroes compelled to, for example, spend a half minute announcing their special attacks while the villain just waits, or to attempt to redeem the villain even though there is clearly no chance of success. (Disclaimer: I recently finished reading [Princess Holy Aura](https://www.baen.com/princess-holy-aura.html), which has [nothing whatsoever to do](https://tvtropes.org/pmwiki/pmwiki.php/Main/BlatantLies) with this answer. "To avert the apocalypse..."!) ]

[Question] [ Merlin the wizard has a problem. Sure, it was a piece of cake to move forward in time to the 21st century, procure a sword that was made with the highest 21st century standards, go back in time, and stick it in a pile of cement. The sword's handle, of course, is imbued with DNA detectors and personality divining spells that will retract the perpendicular spikes at the tip of the blade, allowing he whom the wizard deems worthy to slide the blade out of the rock. So Merlin looks at his handy work, smiling with satisfaction, but as he turns to go a thought pops up - How can he expect the sword to last through the ages? Sure, 21st century grade steel is tough, but will it survive centuries in the British outdoors? Merlin turns back in alarm, sighs and starts working on **making the sword last.** What should he do? He's a wizard and uses magic, sure, but I'd like to minimize the handwaving, so pointing out **specific changes that Merlin would make to the environment** will be appreciated. Also, he's no engineer and would rather minimize the use of technology for this, but he does have **limited access to 21st century tech** (mostly stuff that he can buy/pay someone to make for him, but he can't bring people back in time to help). Also - For **how long** can he get the sword to last (how long in the past can Merlin go to start the sword-in-the-rock legend? The longer the better, as ancient legends go) *Ye olde EDIT the 1st:* to avoid being too story based I'll rephrase: **Set in our world, wishing to minimize handwaving, what minimal changes to the environment around the sword (weather, terrain, maybe society, etc.) would prevent the sword from corroding or breaking, for as long as possible? Said changes should be explained in as scientific a way as possible,** but I'm not looking for diamond-hard science, just a few paragraphs to explain to the readers how the sword lasted for as long as it did. *Ye olde EDIT the 2nd:* **The blade will be steel or some steel alloy. The sword will be used in combat and needs to be stronger than other swords. The idea is to have something close-to-but-somewhat-better than middle ages swords.** A lot of answers go for an all powerful material, but if I do that, it might as well be Adamantium that cuts through walls and shoots fireballs. Minimimalization is what I'm looking for (treks in time not withstanding). [Answer] Merlin knows about metallurgy, and will place in the immediate surroundings of the rock (or even IN the rock) a [sacrificial anode](https://en.wikipedia.org/wiki/Galvanic_anode) made of magnesium, aluminium, zinc or another suitable metal. > > A galvanic anode is the main component of a galvanic cathodic protection (CP) system used to protect buried or submerged metal structures from corrosion. > > > By simply replacing the anode from time to time he can ensure that the sword will last over the centuries. [Answer] ## Make the *Legend* last through the ages So, Merlin telemagicks to 5000 years ago, presents the sword-in-cement LEGEND to some fancy king. Then he rigs up some scenario where the sword is found. People try and fail to remove the sword, the legend spreads. Merlin then causes some event (flood, landslide, magic POOFing, etc) to disappear the sword. The sword is gone but the legend lives on. The sword didn't actually disappear, but Merlin simply moved forward 1000 years to do the same thing. This time it's not a new legend, but a confirmation of an old legend. People try, fail, sword disappears after a while again. Merlin lather/rinse/repeat's a few times, and now you have a sword that has "existed" for 5000 years, but with only the wear and tear of a month or two. [Answer] Can there be hereditary Servants of the Sword? These folks would live nearby, working the earth etc but they take responsibility for periodically going out to visit the Sword and putting a fresh coat of grease on it. Maybe they could have special hats - worn only for the sword greasing, you know. [Answer] Let it rust. Seriously. A thick chunk of steel is already going to [last ages](https://en.wikipedia.org/wiki/Steel#Ancient_steel) without any special treatment. It will corrode on the outside for sure, but this adds to the authenticity of just how old it is. Maybe build a gazebo over it to keep the absolute worst of the weather off. It'll be way more exciting when "he whom the wizard deems worthy" finally shows up - not only are they able to pull the obviously ancient sword from the stone, but the "personality divining spells" can trigger a spell to instantaneously restore the sword to its original, pristine condition in a fantastic display of light/sparks/electricity/whatever. This would cast aside any doubt from onlooking skeptics that the bearer truly is someone special. [Answer] If he has figured out time travel why not just have him put it in a time-loop. At the start of every day the sword is returned to the condition it was in when it was first placed into the stone. Or you could go as far as to put the entire location of the stone into a time-loop (presumably a sacred grove or hilltop), thereby removing any possible deterioration due to weather/time. It would also allow the grove to retain the season it was in when the sword was placed, which would serve to feed the legend as the grove is perpetually the same every day regardless of the time of year. [Answer] Similar to Josh's answer: Use time manipulation to actually halt the flow of time for the sword and stone. This solves a couple of issues. The sword won't rust, the stone can't be chipped away and no one can remove the sword until the chosen one touches it and removes the time stop spell. Of course, if I lived nearby, the young Arthur would have to gain access to my wood mill that I built around a length of blade that never dulls no matter how many logs I split by forcing them against the blade.... [Answer] As KOZM points out, stainless steels exist now, and you can source one for this purpose. Let me be more quantitative and list specific examples, based on current knifes for sale. In particular, the alloy used for Wüshhof kitchen knives is extremely stain resistant. It’s rather soft, though, which makes for a flexible blade but needs constant honing. This is called [DIN X50CrMoV15, or material number (W-Nr standard) 1.4116](https://en.wikipedia.org/wiki/W%C3%BCsthof#Formula). It is 0.5% carbon, 15% chromium, with a pinch of molybdenum and vanadium. Knives can be made of *vanadium steel*, which gives the same stain/tarnish resistance as stainless steel but without sacrificing so much hardness. This uses more vanadium in place of chromium. I have an every-day carry folding blade made from [VG-10](https://en.wikipedia.org/wiki/VG-10), and Wikipedia has a [list of steels they have experimented with](https://en.wikipedia.org/wiki/Spyderco#Blade_Steels). VG-10 is hardened around RC60. It is also used to make swords! They also make knives using [CPM](https://en.m.wikipedia.org/wiki/Powder_metallurgy), which is a *powder metallurgy* and is fascinating to look into. > > CPM-S90V (a.k.a. 420V), similar to Crucible's S60V but designed to be more wear resistant with a very high carbide volume and high vanadium content. Appreciated for extreme edge-holding. S90V was featured in a sprint run of Spyderco's Military in 2008. Since then it has been used in several sprint runs in knives like the Manix 2 and Paramilitary 2. While S90V holds an edge significantly better than S30V, both are usually hardened to about 59-61 RC. > > > So you can buy steel today that might easily last that long without any special protection! Add to that a final chrome plating, a [passivation treatment](https://en.wikipedia.org/wiki/Stainless_steel#Properties), and a coat of turtle wax, and Merlyn’s magical ability to keep humidity away from the artifact will hardly be needed. Stainless steel will last for [hundreds of years](https://www.dahlstromrollform.com/best-metals-for-exterior-applications/) *without* this final preparation. [Answer] Merlin picked up more than some cool tech in the 21st century. He picked up our consumer society's attitude. Why bother protecting or repairing the sword? There was a great deal going on bulk-buy swords. Just pop back in time to when he first wants the sword, and then travel forward in small increments, replacing the old sword with a new one each time. Edit, obviously the DNA sensor needs to activate for his DNA as well as the rightful King's. [Answer] There are plenty of alloys, particularly "stainless" steels that temper well and passivate on the surface, and would last many centuries; plate it with gold or other noble metal to give it even more life and spruce it up. [Answer] Just use [**titanium**](https://en.wikipedia.org/wiki/Titanium). (An alloy of it, really.) The question implied Merlin wanted *the best 21st century standard* and that is what NASA and, well, everyone, really, uses when they want something that works like steel but better. Important points: Expensive due to the refining being energy intensive, but is otherwise common material and easily available. Merlin could just buy the sword and while it would be expensive and a custom job, it would not require miracles. More or less works like steel. Titanium has no weird failure modes that make it instantly shatter or dissolve like some other metals have. You can usually replace steel with it and trust it to work. Almost instantly forms hard and thick layer of titanium oxide on its surface when exposed to air. Because of this titanium is a highly reactive metal that is nearly immune to corrosion in practice. It can be used in sea water or even dilute acid. Embedding it in a stone should not be an issue. Titanium has superior strength to mass ratio. The sword would not really be stronger than a sword made of best steel alloys, but it would instantly feel magical due to its lower weight. And lower weight actually matters with swords. Alternately you can keep it weighing the same as normal sword, but make it much harder to break. Or any combination in between. Titanium is also attractive and has been used for jewellery and statues. A sword made from titanium would probably look better than one made from steel. [Answer] The sword is a sword, albeit an exceptional one. Let's preserve it as such, since it needs to function as a sword. But the stone is no mere stone. It is actually a machine that maintains the sword, disguised as a stone! This method allows you to imagine a simple, feasible, and mostly sound scientific mechanism, hidden inconspicuously in something innocuous - as to not pollute history. It is likely the sword will be scrutinized, but the stone may be overlooked. Too advanced for the middle ages, the people would be less likely to anticipate that a stone is not what it appears. Like the stone-facade speakers many people use in their gardens, they can be made to look nearly identical to an actual stone (if not a real hollowed stone) and house a complex machine. Merlin could commission one that includes sharpening, drying, shining and any other capability that would ensure the sword would last indefinitely with the correct tooling, materials and power source (several other answer propose some of these components). With this machine, the legend could be set at its maximum time. This should meet all your requirements simply and cleverly. It accounts for the preservation of the sword, and can additionally be used to include the mechanical ability to wait for the correct owner. It also avoids any corruption of the sword's structural or historical integrity. Where in a sword do you put a complex biometric scanner and sci-fi "personality analytics" software? How would it affect its functionality, strength, weight, and balance? A stone could be enormous both in what's exposed and (like an iceberg) what is in the ground. It has one purpose and would not have any other effects on the story other than a sound scientific explanation of how the sword is housed, maintained and dispensed. Hope this helps your story! [Answer] [Electroplating.](https://en.wikipedia.org/wiki/Electroplating) Your sword - it's made of steel for strength and 'swordyness', but ... you can coat it in something that isn't reactive, and it should keep for a good long time. [Steel is the best thing to be using](https://www.quora.com/Whats-the-best-material-to-use-for-making-a-sword) Gold's the obvious choice - it's nonreactive, and it'll make the sword look 'special'. But it's perhaps a bit too obvious (and too obviously 'gold' which is also something that a poor peasant might take a knife to scrape it off). But something like chromium, will make it still 'steel like' but just really shiny. Or just zinc - a process known as [Galvanization](https://en.wikipedia.org/wiki/Galvanization) which is something that's still used routinely for ... all sorts of things. Select electroplating metal according to need. Expect that when the sword is finally used - it'll need sharpening when it finally does get drawn, and day to day use (hitting people covered in steel with it) will ablate the coating. But it'll still be rust *resistant*, and we can assume at that point, the sword owner is maintaining it. The lifespan of galvanization is [50-75 years](http://www.thefabricator.com/article/metalsmaterials/predicting-the-service-life-of-galvanized-steel) using 'standard' but with a 200 micrometer coating, should be good for around 250 years in a 'benign rural' location. [](https://i.stack.imgur.com/cYmYJ.gif) I can't find a similar lifespan (with a quick bit of googling) chart for Chrome or Gold. But both Gold, or better yet Platinum have extremely low reactivity (lower than Zinc) so I would *assume* they last considerably longer. So I would say - go with go with Platinum - it will look good, won't be 'obviously gold' and it will last a very long time. [Reactivity Series](https://en.wikipedia.org/wiki/Reactivity_series) [Answer] Ancient has a different meaning for people living today than people back then. (~500AD for King Arthur) People living back in merlin's time were generally not literate. Most legends were passed via word of mouth though the generations (which were shorter back then as well) Those who could read typically didn't have access to written historical records, many of which would have been lost during the fall of the Roman empire anyway. I would say that anything before the fall or Rome (~375AD) could easily be considered ancient for people living in King Arthur's time. Given that women had children young back then, "your grandmother's grandmother's grandmother" could be only 100 years in the past. Going by [this](https://scifi.stackexchange.com/a/15563) description of merlin, His "time traveling" isn't really time traveling in the regular sense of the word but rather just "remembering the future" and "not knowing the past". Maybe he can "remember" 21th century steel making techniques to craft the sword without leaving his time. He knows the time when the sword is going to be pulled from the stone as well so now its just a matter of crafting and setting the sword early enough for it to become "ancient legend" if thats only 80-100 years, then it should be easy enough using modern techniques. [Answer] Make the sword out of a non-corroding alloy? Or a heavy coat of Aluminium? The sword out of the stone was only proof of kingship - it wasn't intended to be used in battle. And in some of the legends, [it breaks pretty fast](http://www.crystalinks.com/excalibur.html) so it could be made out of platinum even though you wouldn't want to use it in combat. [Answer] Just a thought... The focus is so much on the sword as a whole, but because the sword is embedded, the blade itself is actually encased and protected by the stone (and therefore not exposed to the elements). A non-corrosive metal for the handle would be just as effective while allowing a metal that can hold an edge for the actual blade. [Answer] You want the sword to have amazing longevity, but not be really that overpowered. That makes sense from a narrative standpoint, but as for actual materials... IANAB (*I am not a blacksmith*) but it seems tricky to get both, and I can't give you a definitive answer about that. Worry not, though, a workaround comes to mind! ## The sword doesn't last more than a regular 21st century sword, but time past differently for it. Merlin can travel in time, so presumably he could make *the sword* travel in time. You go to the year 0 (or whenever, 0 is just to simplify the math) and set the sword in stone. Now you program it to constantly jump forward a set amount after a set time. Let's say you make it so it only stays for the whole month of December and then on January 1st it *jumps* (in time) to the next December. Then, our 2000 years of History would only mean 2000 months for the sword. If, instead, you set it to only appear one day a month, 2000 years is only 2000 nights wear for the sword. Not bad, huh? You've extended its "lifetime" and "the sword that can only be found on full moon nights" make for a nifty legend. [Answer] IMHO opinion Merlin should build a building around the sword in the stone. The building should have a floor, and the sword in the stone (on top of an anvil if I remember correctly) should be on top of a pedestal that keeps it away from moisture on the floor. Possibly the building should be designed with many concentric shells and many floors and roofs, with the sword in the stone in the center most room. And perhaps to make it more impressive the building should have domes within domes within domes with the sword in the stone beneath the innermost dome. No doubt Merlin will have to build robots to repair the building and keep the dehumidifiers running and repair each other and keep thieves out. I note that many artifacts including swords have been found in water in northern Europe, apparently ritually deposited by Celtic peoples. So apparently iron swords do not rust away into nothing during 1,500 to 2,000 years in the water. Many bronze items including swords have also been found in dirt or water having survived rather intact for 3,000 years. Thus it might be wise for Merlin to make or obtain a bronze sword for the stone. Iron did not replace bronze because it was better as much as because it was cheaper and more common. So a bronze sword could be as good as an iron sword and maybe more resistant to corrosion. And maybe gilding the sword before putting it in the stone would help it stay as good as new for decades, centuries, or millennia. [Answer] Make the sword travel backward in time... When you plant the sword it is perfect, but in the past it is getting older and older. This perfectly sets up a legend of a sword in the stone - a mysterious sword which seemed to grow from nothing and was improving in form over time. Of course, this creates some timeline problems. For instance if you plant it the day after you need it, it would exist yesterday, but if it was pulled from the stone then, it would not exist in the past for the legend to work... So perhaps, you could have two swords, one that travels backwards in time (for a legend) and one that travels forward in time (only needed for a single day) which could be pulled from the stone. [Answer] Maybe present The Sword of Goujian . Survived without rusting for 2500 years before being found because the blade contained sulfur which helped to prevent oxidation. [Answer] Cast a spell that prevents oxygen (or water) from reaching the surface of the sword, thus preventing oxidation (rust) [Answer] This is something of a combination of Scott and Mirror318's answers: Add a clause to the legend that the sword is super awesome AND can be instantly brought back to a state of full repair (actually replaced) when brought to Merlin or an approved temple or whatever. With a warning of "tempting fate" or something comparable ominous, if this is abused. And the "sword in stone" is a tough, thick ingot meant to be "restored" shortly after, and made/enchanted specifically for the purpose of withstanding the elements and human ingenuity. And don't underestimate that last part. Think of someone bringing siege engine - class machines to dust the rock and replace the Gordian Knot legend. [Answer] Use a porous stone, envelop it in something oil-tight, saturate the inner porous matter in some stable oil (shouldn't go rancid or polymerize ). Obviously, still provide a mechanism to make sure the well lubricated sword isn't trivial to slide out :) Oil-soaked paper is nowadays still commonly used to package, store and ship non-stainless tool steel items... [Answer] Do we know whether whole blade was stuck in the stone or just a part of it? Suppose whole blade is emerged in the fake-solid stone. There is a hollow full of synthetic oil to suppress any degradation of the blade. There is a bayonet mount disguised decorative-magic engraved symbols and it contains pure gold ring which serves as metal sealing. The bayonet is connected to the DNA detector and releases the sword at appropriate time. There are also rubber, viton or silicone blades just to remove the oil when the Chosen One (TM) pulls the sword out. Therefore the only part of the sword to face the ages is the handle. Luckily for Merlin there is a plenty of commercially available surface treatments to enhance the oxidation resistance and appeareance. There is hot bluing and black oxidizing finish which gives the oxidation resistance (oxides usually do not oxidize) and dark blue-black matte finish. Thin film of TiN will give the oxidation resistance and gold finish, TiAlN will give purple finish. He can also look for TiO2 film which can be superhyrophilic and when illuminated by UV light it can clean itself from bacteria and algae. Merlin can also look for rare-earth metal oxide coatings which can provide hard and superhydophobic surfaces. [Answer] The sword is actually made from a substance that is more like fiberglass than traditional metallurgy would see; the blade has been infused with carbon nanotubes, which is part of what makes Excalibur so strong. The nanotubes actually poke out of the surface of the steel blade, and therefore microscopically Excalibur is extraordinarily bumpy, which grants it an incredible property: it is [ultrahydrophobic](https://en.wikipedia.org/wiki/Ultrahydrophobicity); water just cannot stick to it because it would rather stick to itself. In addition the surface might also be [antimicrobial](https://gizmodo.com/scientists-accidentally-discover-incredible-bacteria-ki-1472084396) for the same reason; it might shred apart microorganisms that try to live on it. As a result, the cracks might be capable of holding oily molecules for a very long time, so that they also keep oxygen atoms themselves at bay. The main place where this may not work (due to ages of wear and tear eventually eroding the nanoscale surface away) is the handle, which is coated with a thick layer of gold and therefore does not corrode in the first place. Just to make sure, the "sword in the stone" is actually stuck into a cliff face inside the forest -- Merlin has bored a large hole into a small rocky cliff, leaving a large bump in the center where the sword has been stuck. The space functions as a natural shelter, keeping the usual moisture and rain at bay and also making it impossible for other kings down the ages to install the sword-in-the-stone in their courts as an artistic piece. It is perhaps even raised up many feet above ground level, so that one has to shed one's armor and do some rock-climbing before one can even attempt to pull the sword out of the stone, so it is more a pastime for young kids than for serious knights. [Answer] How about having the sword appear for some significant annual event- one day only each year. With time travel, Merlin can soon build up a long history. The sword could be fixed into the stone by a modern adhesive, such as an epoxy that protects the blade. Merlin can release the blade at the right time by some simple heat magic that causes the adhesive to break down- at a temperature that does not harm the steel. [Answer] If he can go a bit further into the future, then nanites are the obviously choice. Either everything is made of nanites or maybe just a thin layer in the stone. They constantly refresh the surface, and consume the stone for energy and materials. A bit more realistic, maybe graphine. [Answer] **Check when the sword was destroyed before going back to place it**. Making a sword last the ages *sounds* easy. The problem is, everybody has heard this story about how the person who pulls it from the rock is the true King. And every *King* who rules over that rock is staring, balefully, at a *seditious* sword that is *telling every filthy peasant that looks at it that he is not the True King*. That won't abide. So this sword needs to be proof, not just against the rain and snow, but against teams of horses, thumbscrews, cannonballs, monster trucks maybe (depending on when the sword was meant to be claimed). Worst of all, it faces *the metal file*, wielded by a tremendously strong and dutiful slave whose life depends on meeting a deadline. If that fails, the King can simply have the entire hilltop removed and hauled on a massive barge out to sea. So Merlin travels forward in time after he places the sword until it is destroyed. Then he sends himself an instant message that arrives right before he went back with the sword, telling him to "go back to *this* time instead". So Merlin actually takes the sword (the one original sword he made up, there is no other) back to *that* time and puts it in place, and then he goes forward until the sword is destroyed, and sends himself an instant message received a few moments before the IM above would have been received. Obviously Merlin goes back only once, to the very latest time when the sword was seen to appear, taking the only copy of the sword, and is pleased on shifting back forward to see the rightful King claim it. All the other times it has been seen, all the mad false Kings trying to dissolve it in aqua regia or melt it in a blast furnace, only to see it reappear -- that is just dead history, which he has done nothing to change. [Answer] He doesn't, obviously. He can time travel, so instead of bringing back a sword from the 21st century (what an odd time period to pick to locate a sword in, by the way), he brings back a [planetary annihilator](http://futurama.wikia.com/wiki/Planetary_Annihilator) from the 31st century. [Much more effective choice than any sword](https://www.youtube.com/watch?v=cNUFJGeV8x4). Seriously, the idea of time travelling to bring back a sharp hunk of metal is beyond absurd. But he's a magician, so he doesn't need time travel, he uses magic. A spell of "remove moisture" or "prevent rust" envelopes the sword, keeping it in pristine condition throughout the ages. You're way-overthinking the story about a magical sword and the person with the magical ability to remove it from the stone that's magically holding it. ]

[Question] [ This is, for the record, the same universe as in [Is space piracy orbitally practical?](https://worldbuilding.stackexchange.com/q/62937/627) and [How can I prevent Kessler Syndrome among space stations?](https://worldbuilding.stackexchange.com/q/63923/627). In my world, circa 2100, space stations orbiting Earth, Venus and Mars provide transit hubs for the inner Solar System. Small shuttles take people to Low Earth Orbit, and larger ships ferry them from there to other destinations, following flights similar to [kingledion's suggestion](http://chat.stackexchange.com/transcript/17213?m=33996835#33996835) (from Earth to Mars, a 3.60 [km/s](https://en.wikipedia.org/wiki/Delta-v) burn, via Hohmann transfers). Currently, Pan-Solar Spacelines has commercial flights to: * Earth, Venus and Mars * The Moon * The asteroid belt, once a month * Flights to the Jovian moons, primarily chartered by major governments sending publically-funded exploratory missions. My traveler is about to head to Mars from Earth, immigrating to the newest polar colony. However, his flight is delayed, because of [X]. I'm trying to figure out what [X] could be, in terms of a *uniquely space-based* delay. This should rule out Earth problems like normal weather and congested flight paths. **What are the main problems that will plague spaceliners in this world?** --- To be clear, I'm not looking for overly fanciful one-time-only disasters that could cause delays, but more **normal and common issues.** Suggesting the outbreak of war between Earth and Mars, for example, would not be a normal event and is not what I'm looking for. [Answer] # Someone detected an asteroid There are lots of small asteroids. Even in 2100, when the solar system is well mapped, carbonaceous asteroids with low albedo will be very hard to detect passively. Further, radar is relatively ineffective for scanning the vast distances between Earth and Mars. A few hours before scheduled departure, a freighter coasting to Mars detects a small 100m asteroid on passive IR, and reports to the Solar Coast Guard. A notice-to-mariners is sent out to all ships in the inner solar system. Most flights are unaffected but Martian Spacelines delays a scheduled burn in 6 hours time for an Earth to Mars transit due to uncertainty about the asteroid's whereabouts. Given that their ship intends to burn once and then coast for months, it is very costly to have to make a course correction mid-flight. Since the passengers were still in the terminal, they delayed boarding to prevent unnecessary waiting. The Solar Coast Guard contacts Traffic control Mars (TCM) to update the asteroid. TCM fires up the phased array on the nearest deep-space radar station and detects the asteroid. After an hour of study, they have a confident plot of its course, and release another notice-to-mariners. Martian Spacelines re-checks the nav plot, confirms the asteroid is not a problem, and boards the flight, 8 hours late. Not really a big deal, given the months of travel time. # Coronal Mass Ejection This story is a lot simpler. "Coronal Mass Ejection detected", said the voice on the loudspeaker as the alarm lights flashed yellow, "estimated bow shock arrival time is 11 hours. All spaceflights have been secured. All station personnel report to emergency radiation shelters. All passengers report to your carrier information desk to find your designated shelter spot. " [Answer] **People aren't there to transport** Perhaps this space line has an agreement that it won't leave until all the customers have arrived. Given the time between each flight, this might be reasonable though potentially costly in terms of extra fuel required to compensate for a sub-optimal launch time. **Technical problems** The spaceship toilets are out of order. No one wants to get hit with hyper-velocity feces. **Fueling problems** If a problem with the fuel is found, that will delay departure. Say, the hydrogen is contaminated with something that will really mess up the engines. Purging the tanks, cleaning them and refueling can take a long time. **Space Traffic Control Congestion** There's lots of ships coming and going. As with terrestrial airports, if a take-off window is missed, it may be hours before there's another opening in the take-off schedule. **Worker Strikes** The technicians required to make the station work are on strike. This could be the fuel union, the engine repair union, or the hospitality union. **Piracy** There are pirates in the area and they need to pass before the flight will leave the station. **Kessler Syndrome** Something very big has exploded into lots of pieces that are now spreading out over an important orbit. Finding a hole in all the debris may take some time. Cleaning up a Kessler event will take a very long time. **Solar Weather** Perhaps there's a particularly nasty coronal mass ejection or solar flare headed towards the space port. Given that most trips will happen outside Earth's shielding, intentionally putting humans in the way of such energetic events is willfully negligent. I predict huge court awards against a company who ignores solar weather predictions. [Answer] The real problem with spaceflight in the plausible mid future is that there are specific "windows" that need to be met in order to achieve minimum energy trajectories (or indeed, any trajectory; the timing of the window changes with the trajectory chosen). So there can actually be no "delays" the way we see in a modern airport or train station, if you miss the Mars launch window because someone was late boarding, you need to wait almost *two years* before the next synodic period lines up the planets. No space line is going to provide two years worth of hotel vouchers, so the "Martian Queen" is blasting off on the mark, and any unfortunate passengers who missed the flight are on their own. This also provides an interesting observation about spaceflight. Since synodic periods are well known long in advance. spaceships will be launching at almost the same time leaving a "convoy" of spacecraft heading to the same destination. The spaceports will also be equipped to deal with "surge traffic", so people living and working at the spaceports will see massive increases in business whenever the synodic periods occur, and you can imagine prices will also rise to reflect that (squatters at the Deimos spaceport will be ejected every 18 months or so to make room for the high paying passenger traffic. So the real struggle isn't going to be spacecraft being delayed, it is going to be dealing with the sudden surges in traffic, price gouging and the sharp operators who are trying to work the system to get the best deals. People who "miss the boat" are also going to have to find a way to live for the next synodic period before they will even be able to book a new flight (and there may be a subculture which tries to make people miss their spaceflights and then keep them as indentured servants on the planet working off their life support bills). Much like the idea of space piracy, the reality of space is far stranger, and the problems people are going to face will be much different than what we are used to. Being stuck on a planet might actually be a hostile act by "slave traders" seeking to get enough indentured servants to fill work contracts on Mars, for example. [Answer] Give an obviously fake reason that your main character realizes isn't feasible, and then have it really be due to something fun, like a colony revolting, or an outbreak of Space Black Death. Or, more mundanely, you didn't fill out form AE-37 on your Global Exit application, and need to be questioned about it, but you did fill out BC-12, which authorized you to enter the space station. The Global Exit authorities aren't allowed on the space station due to a Union Contract, and nobody can legally question you about the form. They also cannot let you board a spacecraft or return to the surface. Alternatively, someone's name on the manifest matches a name on the Pan-Galactic No-Fly list, and the shuttle is not authorized to dock until it is all sorted out. Add Bureaucracy and simmer on Low until resolved. [Answer] I came up with some basic ideas before posting the question: ### [Space weather](https://en.wikipedia.org/wiki/Space_weather) Radiation problems can severely damage a spaceship's instruments, making navigation and flight severely dangerous or impossible. Additionally, impacts from micrometeroids/debris can damage the ship, even if protections like [Whipple shields](https://en.wikipedia.org/wiki/Whipple_shield) are in place. While the spaceliners should be prepared to deal with a minimal level of such problems, and unforeseen impact could mean substantial delays. Additionally, electromagnetic events could cause damage a spaceship's communication systems, which would be imperative for any journey. There's virtually no other way for control centers to track it, or to know the status of the mission. Without communications, the ship is crippled. Fixing the systems could cause a decently long delay. ### Fuel/oxygen leak [*Apollo 13*](https://en.wikipedia.org/wiki/Apollo_13) had to be aborted because of the explosion of an oxygen tank. While the astronauts made it home, thanks to some ingenuity on Earth and in the ship, it was an extremely close call. Airplanes do have issues with depressurization, and have crashed because of explosive decompression, but in a long space mission, losing even a tiny bit of fuel or oxygen can be devastating. It's nine months to Mars; a small leak before leaving the space station could kill the crew. If there is a problem with this, there will almost certainly be delays. ### Delayed Earth-to-station shuttles People have to get to the space stations via small shuttles, which are quite more extensive than airport monorails or taxicabs. If one is delayed or has a problem, approximately ten people could be left on the ground, or could be dead. Spacelines will be very reluctant to let flights go before everyone has boarded in such a case - except in cases of extreme shuttle delays - because space travel is not too cheap, and not exactly regular. If you miss your flight, you could be set back days or weeks, and spending that time on a space station is not fun. At the same time, going back to Earth is expensive. It's since been pointed out that alignment issues could mean that flight windows are narrow. A large amount of flights in a short time could mean that a person could always maybe catch a later flight, and waiting just for the sake of a few passengers could set the others back a long time. It seems that the spaceline might prioritize the rest of the flight. [Answer] I'm going to start with one you don't want. # Ordinary weather Pilots will need to spend a certain amount of time planetside to [stop them going blind](https://www.washingtonpost.com/national/health-science/the-mysterious-syndrome-impairing-astronauts-eyesight/2016/07/09/f20fb9a6-41f1-11e6-88d0-6adee48be8bc_story.html?utm_term=.48bfcebda45e). The weather has delayed his launch to orbit and hence the ship he was piloting. [Answer] **Unexpected Decontamination Delays** On the previous flight some freight crate broke and spilled its contents in the freight hold. Since the quarantine rules for space travel are much more strict than for earth travel, the entire freight hold must be thoroughly decontaminated now. And since space travel is not as much developed as today's air travel there are no replacement space ships available on short notice. **Ships and Resources Needed For Emergency Flight** An emergency has occurred on a Jupiter moon (accident, plague, ...) and an emergency flight from Earth to that planet must be performed to help the colony. Two story possibilities: * space travel is not very advanced yet, so for an emergency flight the scarce resources at the space port (fuel, ablative shields, entire ships that will be sacrificed during the unusual flight) must be bundled to allow a faster flight. All non-emergency flights must be delayed until new resources have arrived from Earth. * space travel *is* advanced, but the required alignment of the planets means that only in very narrow windows the trip is possible. This is usually no problem (since the planet movements are very predictable, so the flight are just scheduled accordingly); but there is no flexibility. So if an emergency flight causes one of the travel windows to be occupied, the entire planned schedule must be thrown out of the window. Disclaimer: I don't know if the travel windows are really that narrow and can really only be occupied by a single ship. [Answer] ## It's not a delay It's just cheaper to get in orbit earlier and wait around then to get an orbital flight just before your inter planetary flight. I would liken this to a person taking the bus to the airport instead of a taxi. It is cheaper but you don't set the schedule. Thus you have to wait around longer. Another option is the "just in time" orbital flights were all booked up years in advance. So you need to take an earlier one and then wait around. [Answer] **Cargo gets priority** I'm reminded of the game [Gazillionaire](http://www.lavamind.com/games/gazillionaire/) where the space ship operator is primarily shifting around commodities. Taking on passengers is a secondary concern. If some shipment has too much mass there is a needed emergency repair part, or even a simple math error the ship needs more space or less mass. Passengers get cut first because that cargo has to go out, the passenger can chill out in his bunk. [Answer] **Goddamit Bill, your space passport is due tomorrow!** you clearly didn't remember that your earthling country passport is valid to travel to our glorious international commute station, but that you need a Interspatial International Passport (IIP) to get out of the earth's orbit! You are now stuck a Saturday afternoon ( Local time ) in a waiting room near the main hall, expecting a video call from your representative in the GESA (Global Earth Space Agency), who will inform you of the procedural of requesting a new passport. You're lucky though, there's a lot of stores, ATM's and atleast two restaurants of each type of cuisine in the solar system. Guess you won't fly until monday, atleast. PD: **Another option could be** : Hey, you didn't vaccinate for Mars Flu, you can't board until you visit a medic practician, and they're all off until monday. [Answer] * A small delay caused the ship to miss a [launch window](https://en.wikipedia.org/wiki/Launch_window). Now they have to wait for the next one. * Some arcane bit of legislation gives traffic precedence to solar sail craft. Highly energetic drives may not be used where their exhaust endangers the fragile sail. (Or does that count as congestion?) [Answer] There's no need for anything outlandish, you can look to what happens in the real world: **Bad industrial relations** Strikes by a union are a relatively common reason for flight or mass transit delays in the real world. The company running the flights has got into a protracted dispute with its baggage handlers/pilots/spaceport operatives/flight controllers/whoever and flights are disrupted for a long period. Optionally, the remaining flights are rationed to the most important travellers and our hero doesn't make the cut. There is also potential, if you want it, for narrative interest in the reasons behind the Union action which is likely to be considerably more interesting and fruitful that a coronal mass ejection or similar natural occurence. [Answer] Lots of very good answers this late in the game, but I ran across your question and had a thought that felt unique enough to warrant a small entry. Fuel Logistics will play a very big part in a society where spaceflight is common and matter-to-energy conversion is still just science fiction. **"Station Maintenance"** A week prior to a scheduled launch, several innocuously small events required maneuvering thrusters on the LEO station to be fired a few more times than anyone really anticipated, and now the station is 'low' on fuel. There is no actual danger of being unable to maintain an orbit, but as a safety measure, with a good margin for error, this one particular LEO station - the one you need - is standing by all incoming craft for two orbital periods, during which a fueling craft will have docked with it; it's not that a passenger shuttle *can't* transfer fuel to the station, but they don't carry enough spare for it to be meaningful except in life-or-death situations, because it's spare *for the passenger shuttle*. This very conservative 'fix' is standard practice, and it is accomplished by simply moving up the time table for the regular supply launch vehicle. The trade off for the delay is that the orbital platform has an opportunity to properly address any operational or safety margins prior to taking passengers; safety margins stay as wide as feasible for all non-crew passengers. The protocol became standard practice when earlier stations had some close calls while performing maintenance burns with ships and passengers docked, using extra fuel and coming rather close to having a bad day in general. [Answer] I'd be tempted to go with a classic homage. Waiting for a supply of [lemon-soaked paper napkins](http://hitchhikers.wikia.com/wiki/Frogstar_World_B). [Answer] I'm no astrophysicist, but if the space station(s) themselves are in orbit around their respective planets, then there would only be particular windows of time where you could launch from Earth to Mars, right? If the ferry's departure is delayed too long by more mundane means, then the *planet Earth* (or even just its gravity well) will become an obstacle to ships trying to launch towards Mars, and then they'd have to wait until the space station orbits around the planet again before they can take off. Passengers in such a situation would probably not want to go back down to the surface - even if the delay is the better part of a day or longer - simply because the cost and/or effort required to get to and from the surface is a hassle in itself. This may or may not be a fairly common issue in space travel, depending on how often the ferry gets delayed from its planned launch window because of technical reasons. For an even longer-term issue, the *alignment of the planets themselves* would create "blackout ranges" where it's just not practical to run the ferries. If Mars is currently on the other side of the sun from Earth, for example. In these cases, the space-liner companies would likely stop booking ferries well in advance of a blackout, though, as it could be months or years before the planets are close enough again to make running ferries feasible. This is probably not useful for the specific story point you're setting up, but it's something to consider as a background element to the setting. [Answer] ***Something 'really big' struck the Moon.*** There's a glowing crater, lots of debris splashed into space, and some of it is heading toward the ring of orbitals surrounding the Earth. The AIs, as powerful as they are (it *is* 2100, right?), need to get together and 1) model the dynamics of the debris field in virtual precog mode, 2) redirect the [Kessler laser turrets](http://forum.nasaspaceflight.com/index.php?topic=16192.10;wap2) (we will have needed to be prepared for this for some time now) to vaporize the small stuff or steer by surface ablation the larger stuff. Some incoming ships within a certain window of arrival are hosed (the early ones dock), but thankfully we have a large fleet of autonomous refueling drones, and ships can redirect to the small, hollowed-out asteroid stations parked at the L1 and L2 [Lagrange points](https://en.wikipedia.org/wiki/Lagrangian_point#L1). BTW, FWIW, I'm thinking that orbital spaceports wouldn't be in very [low-Earth orbits](https://en.wikipedia.org/wiki/Low_Earth_orbit), would have really good stickyhulls (orbiting Kessler sweepers), and be the safest places to be if you couldn't make it back to the surface in time. Phew...glad I cleared that up.... (BTW again, this scenario would be more in the judiciously-fanciful than the overly-fanciful category, right?) [Answer] ## Security Interplanetary transit is plagued by many issues related to crime: * Smuggling of proscribed goods - everything from drugs to subversive literature to gene-modified animals and plants * Attempts to evade currency transfer limits * Wanted criminals trying to escape prosecution * Terrorists * Fencing stolen goods When the various security forces (planetary, orbital, commercial) suspect an attempt to use interplanetary transport to break the law, they can prevent ships from docking and undocking while they investigate. Sometimes these lockdowns are done randomly just to keep the criminals nervous. [Answer] Important politicians or VIP will jump the launch window queues, delaying the lesser priority traffic by an orbit or two. [Answer] **Some unexpected spacecraft got in the way** Some people who do not have authorization from whatever authority that coordinates all launch sequences decided to put their own spacecraft in orbit around the Earth not very long before your flight was scheduled to begin, and its trajectory comes so close to the flight plan that flights must be delayed by several minutes just in case the new spacecraft explodes into a potentially deadly shrapnel cloud. [Answer] Im basing my answer in these two comments: > > [Kys](https://worldbuilding.stackexchange.com/users/16335/kys): You're asking this about the same universe as space pirates and you > wonder why there might be delays > > > [HDE-226868](https://worldbuilding.stackexchange.com/users/627/hde-226868): In what I can only refer to as the Golden Age of Piracy, I'm guessing > there weren't too many shipping delays because of piracy. In theory, > it's a threat you can't predict. You can only hope for the best, and > deal with it when it happens. > > > In the Golden Age of Piracy there was not quick communication, so what would you do? Wait for a letter sent via raven by other ship? Even if possible, with the delay it would be unhelpful so you just set sails and hope for the best. Circa 2100 maybe you can´t detect those nasty space pirates (although you [totally](http://www.projectrho.com/public_html/rocket/spacewardetect.php) [absolutely](https://worldbuilding.stackexchange.com/questions/23313/stealth-in-space-how-realistic-is-it) could, but let's say you can't because you want pirates to be a *thing*), but what you can do is to communicate with Earth with, at most, a few minutes delay. Other spaceships might send reports of sightings or attacks, and your flight would be delayed for a few minutes/hours until the spaceport security (or the army or *whatever*) makes a whole DRADIS sweep, assesses the situation, evaluates the risk, checks with their legal/insurance department and finally gives the spaceport the green light, which kinda means "the protocol says the course is safe enough", so the spaceship could still totally be raided if you so please. [Answer] I’ll elaborate more on something o.m. posted: mixed sail/rocket use. Sails are *huge*. Something might go wrong with one, damaging the rigging or otherwise fouling the sail. After repairs, it needs to maneuver to get back on course, or otherwise chart a fresh course. This is not a slow Hohmann orbit, but a constant power situation. Think fast clipper ship among all the barge traffic. Now high thrust rockets used for setting up Hohmann orbits can damage a sail, so traffic control must plan for their positions. The plume can stay hazardous for millions of miles! So, a sailcraft having an emergency failure will cause a black-out of “burns” until it is repaired and a new course registered. If you don’t know exactly where it will be, you can’t be sure your burn avoids it. Until it is repaired, you don’t know how far off original course it will get, and have to black out larger tragectories for burns as time passes. Just be sure the directions make sense. The lightcraft needs to be in the opposite direction of the ∆v maneuver. But the ∆v isn’t in/out but east-west to change your orbial speed. Sacrifice [a few Kerbals](https://explainxkcd.com/wiki/index.php/1356:_Orbital_Mechanics) to get the feel for it. So, is that unique enough, relative to prior travel delays? [Answer] There are several types of reasons, and we can ball them up in some categories: # Social & Economic ## Pilot strike We see it when larger aerospace companies or the aerospace control in Europe go to strike nowadays: nothing moves, no passenger gets off the ground. This does stop almost all traffic. ## Bureaucracy The future might be a huge mess of bureaucratic barriers everyone needs to climb over to get his flight. And skipping any might mean to miss not only the next flight, but to go through all of them again. ## Quarantaine Anyone traveling to the stars might need to keep up a very strict quarantine regime, which gets extended for a long time if they even sneeze! Unlucky you, that you had dust on your nose at the wrong moment. ## Overbooked Ever stood at the airport and couldn't get your plane because the plane was overbooked? Maybe the company running the space transport just did the same... and only has a monthly or wider spread flight shedule. ## Religious ban There might be days when the most widespread religions ban interplanetary travel due to some reasons. # Environmental ## Impact Season Space debris is out there in tons. Some collide with earth all the time. But a spaceship has less protection from passing space rock than the transit station, and even that is not perfectly safe... but better than being out there. ## Damage No matter if it is the ship's coolant leak or something: repairs in space are notoriously tricky and slow in 0g environment. This can delay travel really long, as there might not be replacement ships or parts readily available. ## Transfer Window closed Now, space travel is clearly time-dependent. Due to a pileup of tiny errors like a docking clamp not opening properly, a tiny error in the data input into the autopilot and a hysterical woman during boarding the whole process of getting off station and onto the right facing to intercept earth just took way too long. In extreme cases, half an hour can decide if the fuel in a spacecraft has a chance to intercept a target with corrective burns or not. So the craft has the unheroic solutions of either getting rid of cargo to increase the stored fuels reach... or to return to the station and wait for the next window to open or restock on extra fuel. [Answer] **Meteor or other orbital debris impacting something critical to refueling.** Maybe a primary tank gets hit -- or worse yet, maybe the main fuel distribution manifold gets shredded. Certainly repairable, but probably not fast, especially if key personnel are injured as well. Vacuum welding of metals can get tricky, even with all the right tools, supplies and energy source. [Answer] Technical failure. Just like airborne flights are often delayed because a final inspection finds a failure in the equipment. A circuit board was knocked loose by vibrations. A fuel loader missed one of the tanks...because the company hired cheap, dumb people for the position. Human delay...a man forced to stay in space one day longer than his psyche can take, goes on a rampage, destroying the flight computer. The pilots are drunk...again. The stewardesses are fighting over duties. [Answer] Not exactly sure this is what you're looking for; but since gravity is far lower on Mars than on Earth, your traveller's may need to be delayed so that they can undergo some training to rebuild muscles, else they won't be able to function normally under the relatively intense gravity of Earth. Mars gravity is 3.7 m/s^2, wheras Earth's is 9.8m/s^2. Which is a considerable difference. For instance a 38 pound person on Mars will weigh 100 pounds. Imagine if you suddenly had to carry around an extra 60 pounds, (or in relative terms it sounds even more; carry an extra 1.5 of your own body weight). [Answer] Flight crew and cabin crew had their monthly radiation check-up and it was found that the **pilots accumulated more than their monthly allowance of gamma-ray exposure**, possibly due to navigating too close to the beam of a [gamma-ray burst](https://en.wikipedia.org/wiki/Gamma-ray_burst) event that month. The pilots were grounded and need to be replaced with a flight crew from Down Under, which will arrive *real soon now*. Shit happens. :-) [Answer] **Communications Delays** It seems someone in the Martian immigration office has failed to file the necessary paperwork for your immigration. On Earth, this kind of paperwork issue could be settled with a quick phone call followed by a fax. Unfortunately, the communications delay between Earth and Mars can range between 13 and 24 minutes. Earth asks for the form; Mars asks for clarification. Earth provides clarification; Mars requests additional paperwork. Earth provides paperwork; Mars attempts to send immigration papers but sends the wrong ones. Earth alerts Mars of its mistake, but the work shift has changed on Mars, so Earth has to recap the entire process. A few more messages go back and forth, and finally the papers arrive, anywhere from 2 to 4 hours later. By that point, our protagonist has missed his flight and will be forced to wait for the next one. [Answer] **Bad Navigation Software** You have not talked too much about how your ships navigational software works, but with this much commercialization going on, it's likely we've offloaded all the actual rocket science to a program. Like all software, there are bugs. Perhaps the captain of the ship your character is waiting for forgot to patch when last at port so the ship isn't using the updated software, so it picks a series of burns that result in a slower route. You could combine this with some of the other delays people mentioned. "They skimped on the navigation software at corporate so we had to take 3 days manually going around unexpected micrometeorites." [Answer] Unexpected decompression in the departure lounge! A micrometeorite has punched a tiny hole in the floor of Departure Gate 13 and the air is slowly leaking out. There's no need to panic, but for the sake of staff convenience and passenger safety, passengers are escorted out of the room and not allowed back in until the janitor has glued a patch to the hull. This is terribly inconvenient for you, because that gate is docked to the big main airlock of the Mars Express, and since the flight attendants won't let you (and the other 100 passengers) sneak in through the little service airlock, boarding is delayed until the gate is declared safe for use without pressure suits. [Answer] It just so happens that today is Intersolar Expo Day!! That's a week-long holiday celebrating the first return flight to Mars! Yay!! Everyone is coming in from the planets for it. You can't get flights out because of all the incoming, but there will be plenty of trips to everywhere at the end of the Festival. Share and Enjoy!! ]

[Question] [ Following on from [this question](https://worldbuilding.stackexchange.com/questions/3714/how-would-an-aquatic-civilisation-forge-tools) and assuming the race in question had developed the ability to create tools how would they approach the need for mass calculation. Our early computers were used to calculate large amounts of financial information, how would an underwater species approach this problem (I'm assuming electrical systems are probably out of the question but I'm happy to accept answers which prove me wrong). I'm looking for a technology which could do large arithmetic calculations and be built and function in an underwater environment. [Answer] Instead of electronics they could develop fluidics: <http://en.wikipedia.org/wiki/Fluidics> We've built fluidics logic circuits to control ICBM's and rockets and nuclear reactors - basically environments that are harsh/destructive to electronics. But we sort of stopped developing fluidics further as hardening process and redundancy algorithms improved to the point where electronics can be used in harsh environments (a side-effect of our space program where space agencies had to develop electronics to withstand space). One down side of fluidics is that it has a maximum clock frequency of tens of kilohertz. But as we've seen since the late 90s, electronics also have a maximum clock barrier (apparently at roughly 4GHz for practical purposes). This doesn't mean that computers are impractical. It may just mean that they would try the parallel, multi-core approach earlier compared to us. The slow clock speed, multi-core limitation would also put pressure on software development to write programs with hundreds of small tasks where each task does very little but working together in parallel can achieve high computing troughput. We've played around with this in the 80s. A notable implementation is [Thinking Machine's](http://en.wikipedia.org/wiki/Thinking_Machines_Corporation) Connection Machine: <http://en.wikipedia.org/wiki/Connection_Machine>. [Answer] Awesome! I can talk about what I think is one of the coolest inventions of all time: the [analog computer](https://en.wikipedia.org/wiki/Analog_computer). An analog (more properly, a [mechanical](https://en.wikipedia.org/wiki/Mechanical_computer)) computer was actually the world's first "computer" - the [Antikythera Mechanism](https://en.wikipedia.org/wiki/Antikythera_mechanism). It was an ancient Greek device that predicted the motions of the planets and other astronomical objects. Only parts of it have been found, but we can figure out a few of its basic properties. It made its "computations" using an elaborate system of gears. Fast forward a couple millennia. Let's go to England, and meet a man by the name of [Charles Babbage](https://en.wikipedia.org/wiki/Charles_Babbage). I'm guessing you've heard of him. He shows up in a lot of books on alternative history, because he's hailed as one of the first computer pioneers. Babbage's first "computer" was the [Difference Engine](https://en.wikipedia.org/wiki/Difference_engine), a glorified calculator that could work with polynomials. It used a lot of gears to work with polynomials and do advanced calculations. Babbage got some funding from the government, but not a lot. Later, he worked on his more advanced [Analytical Engine](https://en.wikipedia.org/wiki/Analytical_Engine), a machine that never got off the drawing board. It would have used punchcards and a more advanced gear system to perform "general purpose" calculations. Unfortunately, funding dried up, and Babbage never built it. Parts of it have been built, but it has never appeared in full form. An underwater civilization could certainly create one of these machines. The one issue would be ocean currents, which could disturb the mechanisms. Perhaps they could shield it with something, or else put it in an area of still water. They could build it out of metal - assuming they could make tools, as per your other question. [Answer] Don't take it personally, but if you think computers are only made of silicon, you must have sand for brains! The first computational apparatus, primitive neural systems evolved in an aquatic environment. For 1.5 million years (or so) they have developed environments that protect them from electrical and mechanical failure due to dehydration. These systems use some elaborate osmotic pressure control mechanisms that not only maintain a narrow band of ionic concentrations (aq) but also run on their transient fluctuations. To your specific question about computers in an aquatic environment think of the real, original neural nets. Think axons, dendrites, and synapses. Throw in a little myelin to insulate yourself and reduce repolarization times and you're on your way. Your silicon devices are chips of the old aquatic blocks and in a few decades may catch up. [Answer] > > (I'm assuming electrical systems are probably out of the question but I'm happy to accept answers which prove me wrong). > > > Let me take a crack at this one. There are two problems with running your standard PC in water: 1. **Conductivity** 2. **Corrosion** Conductivity is bad, as it allows the electricity in the wires to not actually follow the wires and end up where you need it to go. The nice thing about conductivity, is that it's all about [degrees](http://chemistry.about.com/od/moleculescompounds/a/Table-Of-Electrical-Resistivity-And-Conductivity.htm). The wires in your machine are always going to be more conductive than the surrounding material (or else they wouldn't work and nobody would make wires out of them). Salt water is very conductive. Fresh water is not terribly conductive (but air is still 10^12 better). Distilled water is even better (but still likely not good enough). The main idea though, is that as long as the wires are insulated by something to prevent the electricity from jumping wires, it will work just fine. We use air for that because it's cheap and ubiquitous. Aquatic peoples would need something else. (though maybe not [flourinert](http://www.overclockers.com/build-an-underwater-computer/)) Corrosion I know less about, but expect salt water to be a larger issue here as well. The wires would need to be chosen with corrosive properties in mind as well as their conductivity. Most likely, the aquatic race would simply need to seal their computers with some non-conductive, non-corrosive contents, and have the electric plugs well insulated - but they'd probably still work the same way. If anything they might be beefier since the water could serve as an effective heat sink for the entire machine rather than depending on air to carry the heat away. [Answer] Oil immersed PCs and servers exist. They conduct heat but not electricity and prevent water corrosion. <http://www.pugetsystems.com/submerged.php> We imagine upside-down bins to contain the oil (oil tends to float up). The oil is water-displacing( WD-40 can remove rust from a jammed hinge). Electrical (batteries) and electronic (computers) apparatuses can be assembled in water and then placed in the bins, then turned on. We can adapt most of our electronics to this method. And hey, upside-down bins! [Answer] I'd consider the [moniac](http://en.wikipedia.org/wiki/MONIAC_Computer) and [water integrators](http://en.wikipedia.org/wiki/Water_integrator) and early analog computers. You'd probably have a very different environment for computer design - consider that in many ways the jacquard loom was the first programmable computer, and that it used punchcards. And while there were [alternatives to binary designs](http://www.wikiwand.com/en/Harwell_computer), they are consigned to the dusty basements of history. Without this basis, you're more likely to find analog machines. You'd probably start with fluid-analog computers or simple hydraulic switches, possibly used to control simple machines.Eventually you may progress to logic gates, or [fluidics](http://www.blikstein.com/paulo/projects/project_water.html). Computers would *necessarily* be room sized since even with eventual development of microfluidics, you can't hit the same process sizes as a electrical system. As for alternatives, I'd consider electrical circuits as being impractical in a marine environment but the techniques that would lead to microfludics (etching channels in your substrate) might eventually lead to photonic computing. As for storage, [delay line memory](http://en.wikipedia.org/wiki/Delay_line_memory) of some sort could work, assuming we're using analog computers, eventually. One might also consider the use of empty and full fluid channels as a equivilent of 0 and 1 in storage. [Answer] I think this would depend upon the depth of the aquatic civilization. However, I would imagine that an underwater species might rely on a symbiotic relationship with other species in order to achieve something like this. Perhaps a species that uses its own bioelectricity, and based on certain stimuli could return some type of output. (Bioelectricity and bioluminescence are apparently common in very deep waters, as no sunlight penetrates there, at least on Earth.) Depending on how your aquatic race communicates, I'm guessing that arithmetic could be achieved through light waves or sound waves. (In fact, I think it'd be interesting to see some type of mathematical system implemented with sine waves and Fourier transforms.) [Answer] I think they would tend towards biological computers. Many underwater creatures have finely tuned senses that can detect a myriad of impulses. Groups of creatures could link together through this network. Most species already do this to some extent. I am suggesting that the Aquarians take it to the next level. Maybe when a bunch of them get together in a small space they can zen themselves into a state whereby they really can crunch some data. A Think Tank, if you will. [Answer] Insulators can allow for, effectively the same method of electrical transmission we use now... in fact internet and phone cables are laid on the bottom of the ocean to connect the continents of earth. **Fun Side Effect** (well to me anyway :D ): Having stated the above I would add that it would even be possible to pass a controlled current through a tube built from an insulator that is filled with nothing more than sea water. Wires attached to, or as part of, a device would be most effectively water tight. Though, also pretty interesting, I don't think a 'power leak' would actually *prevent* power transmission. Instead, I'd conjecture, this would cause a great deal of attenuation in the amount of power carried. Using water as the means of power transmission may be valuable but I suspect it would have limits in a computational device. Forming tubes of smaller and smaller sizes would be one likely limit. The boiling point of water might be another... I don't believe steam has the same conductivity profile. So in the end, for building small, fast and efficient computers, I suspect the race would discover some other, semiconducting, material (silicone does seem like a very likely choice) much as we did. Short answer, just insulate. Oh, also, while I had thought it before I saw the comment, I wanted to point out that this was said in a comment by Cort Ammon as well. [Answer] As HDE226868 pointed out they could certainly start with physical calculators, (think of the abacus!, and then much later the Slide Rule). However, we need to think of a few things first. As an underwater species how or why would they even develop writing? Chiseling into stone? possible, but paper? Writing came about to extend our memories and computers were extensions of that with the ability to perform calculations for us. So by bring this up it might mean that an advanced water race might be extremely intelligent with an incredible memory. Having to get that far without cheap 'books'. Now as far as electricity, the electric eel does just fine in water so something might be designed along those lines, but for the big problem of refined metals to use, and being submerged in water, would leave things like gold and platinum to not rust away. So I think something with sound and tuning forks or crystals would be much more likely to be used. Of course these would have to be fairly high range sounds to have the least interference from ambient noise. [Answer] We use water for infinity of things despite of we do not live inside it. So the first thing it comes to my mind is they could go to the surface, take some air and use it inside their computers. If the whole planet would made only of water, they could take the oxygen from the water and create air. [Answer] They may be able to make optical computers with lasers, diamonds, fiber, etc. They could also remove the water from the computers - just like how we create a vacuum in order to make light bulbs, they could create a vacuum and remove water (and insert air, or something non-conductive like mineral oil). I should say that the "tools" needed for such devices/production would be more advanced than what is linked to, however the human race didn't start making computers as soon as they could forge something either, and the previous answers include the "geared" and "mechanical" computers that could develop in a very similar way already. One more possibility would be [fluidics](http://en.wikipedia.org/wiki/Fluidics) - basically transistor and other logic gate equivalents via hoses/pressure [Answer] There is no need to assume that water creatures cannot use processes or technologies that require air environment. Some manufacturing processes do require vacuum, or have required in the past (vacuum tubes, for instance). Humans live in the air but were capable of making vacuum when needed. And, for sure, they create water environment when needed (most of the chemistry). Aquatic creatures could make air environment, or even vacuum environment in they laboratories as required. For instance, [diving bell](http://en.wikipedia.org/wiki/Diving_bell) may be possible to make from some shell or water plant, allowing to experiment with air technologies to discover lots of amazing things. In the Earth, [spiders](http://en.wikipedia.org/wiki/Diving_bell_spider) create air environment under water without any intelligence. [Answer] So...don't think the question is "How do you build a computer without electricity?" as much as it is "How would an aquatic species build a computer?" So the Difference engine is a good start, but: 1) There is no reason to believe an aquatic species could not go on land and develop electricity, much as we have run electrical cables across the Atlantic Ocean or gone in electrical powered vehicles under water or used water to generate electricity ourselves. No reason to believe the opposite couldn't be done (although obviously it's easier if your species has a stronger skeletal structure, etc., point for another time). 2) As I said before analog computers starts down this road but to take that point a bit further you do not need electricity to build a computer, only some way to create a register that holds a value -- which could quite easily be done with a hydraulic system. This concept is explained in some depth in Daniel Hillis' excellent book Pattern On The Stone. (amazon.com/The-Pattern-On-Stone-Computers/dp/046502596X), and a Soviet engineer built a hydraulic computer in the 1930's (<http://makezine.com/2012/01/24/early-russian-hydraulic-computer/>). [Answer] Lot of interesting answers here, but it really is very simple: even if they are "aquatic" and live underwater, they could still have their computers - and anything else - on land, just like we have diving equipment and can do sophisticated things underwater. Having said that, they would probably start off underwater so their technological trajectory would certainly look very different from ours. [Answer] Well simple and it already exists on the sea floor. there live bacteria that are linked together by bio-fibers. They are able to exchange electrons over those wires. As a way of feeding (fermenting) garbage on the sea floor. So where there is an overdosis of + they exchange that with bacteria where there is an overdosis of - charge, they can live on give-away and taking electrons (its remarkable). And they are all connected. Its far more dense then the internet.. Structure has something in common with neurons, but we dont know if it thinks yet... [Answer] Cetaceans in general have the capability of using sound underwater in highly sophisticated ways. Maybe it would be possible to simply excavate resonant cavities in the sea floor and have schools of specially talented cetacean-like "choruses" sing a program so that the sound waves interacting with the cavities would produce output that could be directly apprehended. [Answer] OK, so this is assuming that an electric source has been developed. Currently, we do have water-proof technology. This is made waterproof by developing the technology in question, and then coating the entire device in a very thin layer of atoms. This layer of atoms has the power to repel water and/or other liquids. However, applying this process underwater may be much harder. In the current world, we can develop it and then apply the atoms. This means there is two options for the under water race. They can find a way to use the above ground temporarily - in a way that humans use scuba diving suits to go underwater, they could develop suits to go out of water - and develop the technology there, or use waterproofed primitives (NAND gates), which means that everything they build is waterproofed from the very start. Another problem is these atomic layers work for brief exposures. The underwater race may coat it in many layers of the material, meaning it can be exposed for however long necessary (although this will stop the end device from being touch-screen, because after so many layers, touches will not reach the touch sensor.) [Answer] First, you should think about the evolution of the species along with technology. They probably don't make fire as a primitive technology. Do they have hands? Tentacles? Which materials and tools they have? Then, they could be **manufactured using living beings** or their parts, as I propose in this [answer](https://worldbuilding.stackexchange.com/a/104934/18968). ]

[Question] [ While coming up with a medieval era world, I suddenly realized that there was pretty much no defense against thievery except for patrolling city guards which to be honest probably isn't very effective. This is because by the time the shop owners report about the thievery, the thief has most likely gotten away. Traps don't seem feasible as you still need your customers to enter the shop(can't have them falling into a spiked pit) and the shop owner might not have a good reaction time to activate traps in time. A alarm would alert the city guards but then it's the same problem of whether they would be able to respond in time. Hiring protection personnel would work, however I won't accept this as I want the protection to be independent of additional personnel.(This is a story-reason) So what are some ways for shop owners to protect their goods while still displaying them? [Answer] Medieval times are an area of study for me, so let me tell you a little about the way the law worked during that time. This may be a different world, but I can give you a background on history and how theft was dealt with. First, by the time you reached the age of 12 in many principalities if you did not take action against a crime committed which you knew about you were considered a lawbreaker yourself. Everyone in the community was considered law enforcement. Goods were also tracked (as in, each item featured a maker's mark, sometimes even numbered for inventory, making it hard to fence). Crime largely took hold in places where the Lord taxed severely. The Robin Hood legend comes from that. If you didn't benefit the community in some way (robbing from the rich and giving to the poor) most communities would turn you in. Protection from the law once you got to court only worked if you were noble, and, at least a few of these Robin Hood figures were younger sons of nobility, known to the community. They took the risk, because even if they were caught, they stood a good chance of only having to pay a fine. This did not hold true for the desperate men they worked with, who tended to be commoners on the run. Many, but not all, shopkeepers did live in or above their shops to protect from theft. City guards are a supplement. As I said, the entire community was expected to chase, apprehend or stop anyone who was a thief. If you were a male over the age of 12 and someone yelled "stop thief!" you were expected to throw yourself in their way or otherwise stop them. If you did not, you would be brought on charges yourself. Now, let's talk a little about how Medieval shops were actually set up. First, this idea of coming inside a shop and browsing did not yet exist. (Look at the history of Selfridges to see what a revolutionary idea it was, and that was long after the Medieval era.) Most shops had a half door, and flap shelf. Nobody went in the shop--rather, you would look in, and see the artisan at work. Here's a picture from a little later in the 15th Century. [](https://i.stack.imgur.com/QWquq.jpg) As you can see, unlike today, stealing, while possible during business hours, was not as easy as it is today. At night, a flap was generally lowered and locked, and they often used one of those half doors, except with a shelf extending outward to lay their goods upon when showing them. Like the picture below, only with a shelf extending outwards to the street. Glass was rare, so do disregard the glass in the picture. [](https://i.stack.imgur.com/42V2e.jpg) Most shop owners simply worked inside, perhaps with an assistant at the window and buyers would come by and look in or ask to see specific goods. If you have more questions I would be happy to answer them! [Answer] Shopkeepers did not display their goods to nearly the same extent as modern shops. Plate glass is a very modern invention, and even small panes of glass were expensive. Shops had signs outside that told you what they sold. Frequently these would have pictures rather than writing, since many people were illiterate. You would look for a shop that sold the kinds of goods you were looking for, and go in and ask what they had. Things would be shown to you on top of the counter, in conversation with the shopkeeper or his assistant. There was no self-service. [Answer] Dog are man's best friend. Just bring them into the shop at closing and lock the doors. They have keener hearing and much better noses for smelling trespassers. They can also be quite fierce and drive away sneaky thieves. Then there could be physical protection like complicated locks, metal bars, or multiple security points (different locks). Pay protection money to the thieves so that you aren't a target at all. [Answer] This assumes you want a slightly modern style shop with moderately large goods displayed for browsing. Just have a single, rather narrow door with the shopkeepers counter right next to it -- and a club under the counter. The opening to the counter could also be towards the door so that a running thief could be tripped and a sneaky one intercepted. Small valuable goods would be on/at the counter but on the far side from the door. A step or two (up or down) on the way out, and maybe a signboard a couple of feet in front of the door would all slow a fleeing thief allowing more time to raise the alarm or use the club (or a throwing weapon if you want to go down that route). This is actually still done in many small souvenir shops and relies to some extent on the deterrence value of the shopkeeper being on the way out. Even if the shopkeeper can't stop the thief, they get a good look at them (in the light from the door, important in your case as indoor lighting would be very dim). The shopkeepers counter would also be their workstation for manufacture. Again if you've ever been in a small independent shop where goods are personalised (e.g. names stamped onto bracelets), the workbench is also the sales counter. [Answer] Iron bars seems to be the obvious answer here to protect your front windows. You'd place expensive items on the shelves behind the counter. The same as shops in the modern world, the shopkeeper keeps an eye on the customers and uses conversation to divert and show people you're watching them. [Answer] Use fake or old/useless products. Have everything hidden "under the desk" and display only objects that are worthless for the thiefs, like: * Fake item(s) - eg. mould a bread-like shape out of clay and color it * Old damaged item(s) - eg. An old, or otherwise un-sellable piece of bread * A drawing/sketch of the item(s), placed in front of (street stand) or above the seller o the back wall (normal shops) * Or just only one of each type if item you have This method is used even today in shops, mainly in those where they sell expensive products, like jewelry, electronics, alcohol (this may not be used in the country you live). [Answer] What I have seen in traditional markets in Germany is sample products being glued down onto the display. Subtly pulling one off would be difficult. I guess it keeps them neat too. The actual product is kept under the counter and is asked for rather than being taken off the shelf. ]

[Question] [ Those of you who have read Game Of Thrones will know that in the GOT world seasons do not have a fixed duration, e.g., a winter might last three times longer than the previous one. I find most interesting how can this be possible (if it can), from a physical point of view. I have thought about it, and I find it difficult to happen. Maybe a certain orbital configuration may make the season's duration, if not totally unpredictable, quite difficult to guess. The only possible cases I can imagine are a planet constantly approaching its sun (the orbital velocity will increase and thus the seasons' length will decrease constantly) or the opposite case. However, in both cases the length would always increase or always decrease, and not simply vary. [Answer] **Yes and no.** [This NASA page](http://spaceplace.nasa.gov/seasons/en/) has a good summary of why we have seasons (emphasis mine): > > It is true that Earth’s orbit is not a perfect circle. It is a bit lop-sided. During part of the year, Earth is closer to the Sun than at other times. However, in the Northern Hemisphere, we are having winter when Earth is closest to the Sun and summer when it is farthest away! **Compared with how far away the Sun is, this change in Earth's distance throughout the year does not make much difference to our weather.** > > > There is a different reason for Earth's seasons. > > > Earth's axis is an imaginary pole going right through the center of Earth from "top" to "bottom." Earth spins around this pole, making one complete turn each day. That is why we have day and night, and why every part of Earth's surface gets some of each. > > > **Earth has seasons because its axis doesn't stand up straight.** Long, long ago, when Earth was young, it is thought that something big hit Earth and knocked it off-kilter. So instead of rotating with its axis straight up and down, it leans over a bit. > > > Earth's seasons are roughly the same length because the axis constantly\* points in the same direction over the course of a year, so the "side" of it that faces the sun changes. In order to generate more variable seasons, you'd need either the distance to the sun to vary significantly more or for the "side" of the axis to rotate fast enough that it's noticeable over a human lifespan. In combination with the normal rotation around the sun, these will produce three different "season cycles", which will, in turn, combine to produce relatively unpredictable seasons over the course of several years. You can look at the waveform combinations [here](https://www.mq.edu.au/about/about-the-university/faculties-and-departments/medicine-and-health-sciences/departments-and-centres/department-of-linguistics/our-research/phonetics-and-phonology/speech/acoustics/speech-waveforms/adding-waveforms-and-phase) to get some idea of how quickly these would combine into unrecognizability (just think of the waveforms as temperature graphs and derive seasons from that). It's worth noting that each of these three cycles comes with their own odd astronomical effects. **Varying distance** aka "highly elliptical orbit" and/or "off center orbit": The size of the sun will change over the course of a year, appearing smaller at the far/colder end of the orbit and larger at the near/warmer end. This would *probably* have to be fairly noticeable in order to have enough effect on the seasons, but it doesn't have to be huge. (The sun is ~0.5 degrees large, so varying ~0.4-~0.6 might be sufficient, but I haven't done the math.) **Moving axis** aka "precession": This should be a much slower cycle than the others, but 10 years instead of 26,000 would make a big difference. This would cause the "north" star to change in time with the cycle, with corresponding effects on the rest of the constellations. Navigation by the stars would be much more complicated. **Facing** aka "normal seasons": This needs to be a faster cycle than precession, and is related to both of the others, but it should be possible to have a cycle where each close-to-sun approach has a different side of the planet facing the sun, regardless of where the axis is pointing, by varying where the far point is. The "weird" astronomical affect for this one is that the place where the sun rises and sets changes over time, thereby changing the length of a day. \* Earth's axis *does* actually move, but it's so slowly that it takes 26,000 years to [complete a cycle](http://en.wikipedia.org/wiki/Axial_precession) [Answer] I'm surprised no one mentioned [Sitnikov planets](http://www.ams.org/samplings/feature-column/fcarc-sitnikov) yet.  Image found on Wikipedia. There is a **very** unlikely constellation in which a planet moves along the axis through the centre of gravity of a binary star system. In such a system, the planet can oscillate chaotically which, given a tilted rotation axis of the planet, would lead to seasons of varying length. I'm sure this would have other funny effects, and it would be even more unlikely to set up this system with the planet being habitable, but I think it's a very neat explanation for varying seasons. If you don't want your planets to have two suns, one of the stars could have burned out before the planet was captured (I'm pretty sure the planet would *have* to have been a rogue planet that was captured by an existing system to set this up). I'm not an expert in this topic, so I can't provide you with much quantitative information, but I hope this gives you a starting point for further search. For those who understand German, there is a German science blogger who has [written](http://scienceblogs.de/astrodicticum-simplex/2011/12/26/die-himmelsmechanik-von-a-game-of-thrones/) [at length](http://scienceblogs.de/astrodicticum-simplex/2009/01/05/seltsame-welten-sitnikov-planetenphp/) about these systems, especially in relation to A Song of Ice and Fire. Lastly, to address the problem of "why would such a system even exist?" If there *is* any (however remote chance) that this system could be set up, then by assuming an infinite universe and appealing to the [infinite monkey theorem](http://en.wikipedia.org/wiki/Infinite_monkey_theorem) this system is bound to exist *somewhere*. [Answer] Sure you could have an [erratic orbit](http://www.natureworldnews.com/articles/5882/20140204/wobbly-planet-erratic-seasons-spotted-nasas-kepler-space-telescope.htm). This is an orbit that has the planet coming sigifigantly closer to the sun at one point and then much further at its opposite but that the orbit is moving as well. In this way you could have a winter that is much longer than another and then a very long summer. This would be predictable once you understand the physics behind the orbit but I suspect that it would have been at least the 15th century before it would have been even close to understood if it happened on earth. [Answer] I'll offer a substantially different approach from what has been said so far. The orbit of your planet doesn't necessarily need to be eccentric or instable and neither does it need a rapidly oscillating axis of rotation. The cause of these fluctuations in temperature could be similar to our earth's [ENSO](http://www.weatherexplained.com/Vol-1/El-Ni-o-La-Ni-a.html) which is a global phenomenon where the surface temperature on the equatorial pacific ocean fluctuates erraticly over a period of 2-7 years. [These differences can easily reach 3°C](http://www.nc-climate.ncsu.edu/climate/patterns/ENSO.html) between warm and cold periods and are extremely hard to predict. Essentially, the west pacific ocean is generally warmer that the east. Every 2-7 years, this warm spot begins to expand and drifts east. The upward flow of air this causes over the pacific ocean causes more eastward wind and less westward wind, which in turn accelerates the eastward drift of this warm surface water. [How exactly this process then reverses is not entirely clear](https://earthscience.stackexchange.com/questions/377/why-does-the-el-nino-stop) as is the cause for this phenomenon and [what exactly is needed for a cycle like this to exist is also a difficult topic.](https://earthscience.stackexchange.com/questions/724/why-does-el-ni%C3%B1o-only-exist-in-the-pacific-ocean-and-not-the-atlantic-indian-oce?rq=1) So I suggest you do some further reading there. Some prerequisites seem to be a large ocean and not too many temperature fluctuations apart from these effects. (hence why it occurs at the equator). I can imagine that on a planet where there are two large land masses, seperated by a huge ocean, east to west (and another smaller ocean on the other side of course) that has a small axial tilt (and thus barely noticable traditional climates), these effects could cause what would seem like irregular seasons. [Answer] # Co-orbital configuration It is possible for a planet to change its orbit every so often, resulting in the length of a year changing. This is just one more example among the many answers here of something that could cause seasons to lengthen and shorten in a cycle. An example of a planet that has this property is the Earth. Our planet is in a [co-orbital configuration](http://en.wikipedia.org/wiki/Co-orbital_configuration) with the asteroid [Cruithne](http://en.wikipedia.org/wiki/3753_Cruithne). This means that over the course of a 770 year cycle, the Earth's orbit is mostly constant but changes by 1.3 centimetres, then changes back roughly half way through the cycle. The length of Earth's year is near constant for several centuries, and then lengthens for a few centuries, and then returns to the shorter year. Clearly the difference is negligible for the Earth, but the effect on the much smaller Cruithne is a change in orbit of over half a million kilometres. The length of its year is still only changed by about 2 days (it alternates between a roughly 364 day year and a roughly 366 day year), but this shows that a change of year length that happens consistently every 770 years can be maintained. You may get interesting changes of season if your world is co-orbital with a planet of similar size to itself, or with a planet much larger than itself. The length of the year can change, and also the distance from the sun changes so that winter can take up a different proportion of that year. [Answer] There are several options (as detailed by the answers on this page), but one of the most possible with an Earth-like set-up, is an eccentric orbit heavily affected by surrounding planets and the planet's sun. The majority of this post is a reference from Dr. Irv. Boomberg, of the University of Toronto, Canada, from [this](http://www.individual.utoronto.ca/kalendis/seasons.htm) page, of special interest is [this](http://www.individual.utoronto.ca/kalendis/seasons.htm#eccent) section. The page details that the seasons on Earth actually vary from year to year, but only minorly. This variation is caused to the most part by a slight eccentricity of Earth's orbit. We all pretty much know that Earth's orbit is elliptical, with the Sun being the one of the center points of the ellipse. However, the exact path of that orbit varies, usually because of the gravitational effects of other planets, and the moon. When Earth passes closer to other planets, they pull it off its orbit a little, and when the Earth passes closet to the Sun changes. When the Earth is closer to the sun, it moves faster, but when it is farther it moves slower. This makes a change in the length of seasons. A more eccentric orbit than Earth's would make this change more obvious. The change in Earth's orbit is also partially caused by the Sun's movement. The Sun can be "wobbled" or slightly moved out of the orbital center of the solar system by the gravitational force of Jupiter. This doesn't make a huge difference, but it can affect when the Earth moves closest to the sun, effecting seasons. This means that a solar system with a sun that "wobbled" more, there would be a greater seasonal difference. The final effect on Earth's orbit is the moon. The moon also pulls on the Earth, slightly changing the length and shape of its orbit. There are enough factors for orbital change to have a significant effect on seasons, and many of these aren't very predictable. This could produce unpredictable seasons. --- This [news article](http://www.nasa.gov/press/2014/february/kepler-finds-a-very-wobbly-planet/) gives us another important option. NASA (which published the linked article) used the Kepler telescope to find a very unusual planet. This planet "wobbles" on its axis, much like a spinning top. NASA's first line in the article is > > Imagine living on a planet with seasons so erratic you would hardly know whether to wear Bermuda shorts or a heavy overcoat. > > > Which sounds exactly like what you are looking for. The planet, called Kepler-413b, can tilt on its axis as much as thirty degrees in a year. This means that seasons will change drastically depending on the tilt. Kepler-413b's orbit also wobbles, moving up and down, as well as left to right. It moves enough that it cannot be seen from Earth for years at a time. This would make seasons fluctuate even more unpredictably. Here is an image show Kepler-413b's interesting orbits: [](https://i.stack.imgur.com/5chbK.jpg) Note that Kepler-413b's system is a binary system, so it is possible that could have an effect. [Answer] Our orbit and our sun's output are fairly constant. The sun does however, have a very large impact on our weather, both on a daily basis and over a much longer period of time. The sun has a cycle as well, where it has a 'hot' and 'cold' cycle. A sun with more varied and unstable cycles could very well lengthen or shorten a season, mostly noticeably winter or summer. [Answer] With the right planetary and orbital configurations season lengths could easily vary. Two possibilities come to mind: * A much larger planet with a orbit slightly more eliptical than the target planet but fairly close; this would cause perturbations in the orbit of the *smaller* inner planet. However it would not be a fast thing. Also at least using earth as a guide for development timing, that situation would resolve most likely before much life could develop. Most likely either the smaller planet being captured as a moon by the larger, being torn up into an asteroid belt due to the opposing gravitic forces or being shot out of it's orbit. * Second possibility though it is on a short time frame; an exoplanet drifts by close enough to affect the orbit - though that would likely affect it once and then slowly stabilize to a new normal. Other gravity disturbances could conceivably do the same thing but a long-term (in stellar terms) situation like that I can't envision any reasonable reason. [Answer] Off course you can have some strange orbits, but something like this is possible in planets with ordinary orbits too. For Earth, there are [Milankovich cycles](http://en.wikipedia.org/wiki/Milankovitch_cycles) and other influences that make the climate warmer/colder and dryer/wetter. However, another factor is how stable the climate is. Nowadays the climate is not very stable. Let's compare last two winters where I live (Czech Republic). No need for exact numbers, just how they feel. For the last winter (2013/2014), there were just few days when temperature stayed below 0°C (1 to 3 weeks when added together from some two months, not at the same time), and I noticed only one day when the temperature was around -5°C and there was at least 10 centimeters of snow (i.e. what we call "winter" here). I don't remember the winter before (2012/2013) so exactly, so I'm not sure whether the "true winter" started in mid-January or early February. Anyway, it lasted for definitely more than a month, and temperatures around 0°C spanned lasted to April. So no need for erratic orbit, just place your story in some period when the climate is even less stable than now in Central Europe. [Answer] Yes it's possible also with a binary star system. I tried different combinations with the software Universal sandbox2 and I can say that the only way (that I've found) to really affect the weather is by placing your planet at the same distance Earth-Sun to the closest star and have another star farther away. This second star can be the major or junior partner. If you want something similar to Earth's climate, you could have a star similar to the Sun (G class star) or a little smaller (K star). The other star would be much smaller , like a red dwarf. A small star can be put closer, meaning that it's impact on the climates is more tangible. You can also use a larger star but even if it's several billions of km away, it's heating the planet and it could take centuries to have 1 cycle. Cycles with a smaller star would be shorter. I can't tell how much you can shorten it. At some point, the small star could make the orbit of the planet unstable. Red star could be relatively small, a couple of times the mass of Jupiter. So I guess it could be more or less at 10 AU. To find the impact on temperature on the planet, check [this page](http://www.cartographersguild.com/attachments/general-discussion/66387d1407439779-extreme-planetary-features-vs-realism-math.png) out. Lastly, you don't have to worry about the risk of having two stars in the sky. At best, it's a close small star or a bright but faraway star. I doubt it could be larger than the full moon. To be sure, you might need to calculate the apparent magnitude of the second star... Note: I said this was the only possibility but it's also possible to have a binary star system with both partner close to the center of the system. In that case you might have the n body problem, making the planet orbit possibly unstable. It's possible but the problem is that the movement of the star only provide a small variation in temperature and the cycle is shorter than a season. [Answer] Another possibility that produces varying but predictable seasons: The planet is in a close orbit about a neutron star, it gets nowhere near the jets from the poles. This is the most massive body in the system but it's dark, it doesn't fry the planet. It's close enough that it's sure to be tidally locked so it's "year" is it's day--but this "year" is meaningless as the star is dark. Thus the inhabitants see it as a day. There is a second star in the system in a fairly circular orbit. This defines the year but it is eccentric enough to make seasons. There is a third star in the system, somewhat more distant but close enough to shed substantial heat. How close or far that star is has a big effect on the time of the transition between seasons--when it's close summer is long and winter is short, when it's distant you get the reverse. The year does not change, though. Adding more stars to the mix will make it much harder to predict the seasons (but it also makes the system more unstable.) Having a planet with a non-transparent atmosphere so they inhabitants can't plot the path of the stars will also make it much harder to predict because they can't associate bright or dim stars with the seasons. [Answer] If you combine a highly eccentric orbit, an axis tilt like ours, a variable star like a cepheid, a short axis precession cycle and a short orbit precession one, you'll be able to make almost anything you want. [Answer] The astronomy of seasons can be regular, while the effective seasons (i.e. the weather, despite a constant sun position per date) varies quite a bit from year to year. This happens in many places on Earth, particularly recently, but even before industrial climate abuse. It happens because a planet's weather is complex and not only based on its orbital position, and goes through various phases and anomalies. Some planets' weather seems to be more variable than others, and/or to have shorter- or longer-term storm systems (see Venus vs. Jupiter). In the case you mentioned of *Game of Thrones*, there is also magic. [Answer] One significant thing that people haven't noted is that there is a difference between culturally established seasons and astronomical seasons. The 'growing season' isn't the astronomical 'summer', but the time between frosts, which is going to be widely different depending on where on the globe you are. Some societies, especially pre-industrial, aren't going to be that anal about marking seasons by the stars, but instead concentrating on the environmental effects that define the season. [Answer] I would like to suggest solar activity as one option (sun spots, etc). An unstable star, maybe an old star or something. I think a star near the end of it's life goes through a lot of oscillations beyond just turning into a world destroying red giant. If the planet was on a very nearly circular orbit with a very straight rotational axis, the only noticeable change in seasons would come from solar activity. Basically what they would call winters and summers would be like Earth's ice ages or something. Anything that changes the climate over long periods could be the thing they call seasons. Maybe regular eruptions of some large volcano system somewhere on the planet. An ice age could be too long. But maybe just a period of high solar activity that lasts a few years and caused the planet to be warmer and summery for a long period of time. On the other hand, this would have no effect on the length of a day, so it would be different from winters on Earth. I don't know if they mentioned nights being longer in the winters in the books. But if not, this seems plausible. [Answer] A planet could have 3 axis of different length and rotate on the unstable axis. This makes it tumble, or *podehole*. If the tumbling is slow, perhaps on the scale of a year, you not only have different seasons depending on the current tilt and which hemisphere you end up in, but the sunrise can be in any direction too! Isn't that fun? For a real example, look at a moon called [Hyperion](https://en.wikipedia.org/wiki/Hyperion_(moon)). [Answer] **Under Ocean Volcanic Activity** Most answers so far have focused on a planet similar to ours, having some odd change to the orbital path. I will take a very different approach. Assume a planet similar to ours, with the following exceptions: 1. Oceans are just as large in surface area, but perhaps only a hundred feet deep 2. Crust of planet has large cracks that lead to magma 3. Atmospheric pressure is higher 4. Elevations on the planet vary greatly A general pattern of seasons would emerge, but with unknown length. Water in the oceans covering the cracks dissipates heat slowly, causing higher elevations to cool. The water that does evaporate accumulates slowly in the higher elevations as snow until the oceans are too thin to keep the cracks from directly releasing heat to the atmosphere. The atmosphere is heated directly by magma (unimpeded due to increase in atmospheric pressure), increasing the temperature in the higher elevations, causing the snow to melt and run off back into the oceans. This new runoff creates new river patterns. Depending on the speed of that runoff, it will carry varying amount of sediment with it. The sediment amount and type will cause more variation in the amount of time for starting the cycle over. Assuming the planet would have also had seasons similar to ours, the length of the two patterns intermingling will cause an unknown number and length of "winters", especially with the new pattern having varying length. [Answer] What about the L4 and L5 Lagrange points on the orbit of a giant planet that is in its Sun's goldilocks zone? An object near one of these stable Lagrange points orbits around it, but the orbits are irregular and easily perturbed. They'll take the planet nearer and further from the sun as well as changing it's position with respect to the giant on its orbit. Things get even less predictable if it's a dwarf star rather than a giant planet. They tend to be flare stars but it's the other star that's the main energy source for the planet so maybe the Lagrange planet is far enough away for life to survive the flares? One thing I'm not sure of is whether a planet massive enough to hold its water is "small" enough to have a stable Lagrangian orbit. [Answer] A real-world example: in Cologne, we have four seasons (five, actually, the fifth being Carnival, but that's not a meteorological phenomena). A very short or non-existent Winter (typically a few days in the year where it's reasonably cold and maybe even snow), some Summer (which is either uncomfortably hot or non-existent; the hot state can last for days, weeks or months) and the ordinary crappy weather seasons in-between. An extreme case can be the years where we have no real Summer and no real Winter; in such case, the crappy weather season can span more than a year. I am aware that the original question asks for >planet< having seasons of different length, not a location. However, seasons are always linked to locations on a planet. The equator regions on Earth have little to no seasons, the polar regions have very distinguished seasons. "Geographic anomalies" (oceans, mountains) can influence the local climate and the seasons quite a bit. [Answer] Unless I am very much mistaken, the difference between the moderate climate we had some 200 years ago and the last ice age was that the global mean temperature was 3°C lower during the Ice Age. During an Ice Age, obviously there is much ice and snow, both of which tend to be bright and tend to reflect a lot of energy, preventing the ground below and the air above from warming. So, consider a setting where, due to something like a fluctuation in the gulf stream, the polar regions are 1° cooler than average. This would likely result in a somewhat larger area receiving snow, which would create a little bit more cooling, and so forth. I think it is conceivable that this could lead to a mini-Ice-Age, at least regionally. If the spread reaches far enough to the south, the "corn belts" could be affected, and in turn affect the food supply of a much larger region. Weather is quite chaotic and hard to predict, but I think that with a somewhat more fragile setup, it should be possible to have much more erratic seasons, simply based on small coincidences adding up. [Answer] [](https://i.stack.imgur.com/t1T1n.jpg)I'm surprised no one has pointed out that the opening animation in the show displays a solar system of ring worlds around a central star and different rings at different orbital inclinations that appear to be changing over time, resulting in variations of shadow seasons for the outer rings. This is consistent with the zoomed in maps that are in the opening scenes as well where the world's curvature can clearly be seen to be consistent with a ring. I noticed it in the first episode when I watched and was a little surprised they never addressed it directly, but I watched the whole series and didn't notice any scenes that would be inconsistent with this world structure. This discussion with the title sequence creator even mentions the concept of the world being inside a dyson sphere: [Link](https://www.artofthetitle.com/title/game-of-thrones/) ]

[Question] [ It's a fairly common trope in fantasy worlds/stories that dwarves don't use cavalry. But is there any real reason why? Off the top of my head the two most likely ones seem to be: 1. Their size. Except children ride horses, and jockeys tend to be quite short. And elephants have been used as mounts (though I'm not sure they were ever genuinely used in battle). It might be more of an issue in battle I suppose where having assistance to mount and dismount isn't likely to be possible or convenient. 2. The fact they live in mountains / underground. The enviroment might be more of an issue, lack of grazing etc. But maybe they ride something else instead of horses? It would seem to me that for a race of people who are short and not very mobile cavalry is exactly the kind of thing they would want to aid them in battle. So, assuming traditional fantasy dwarves, is it just a thing that has become accepted in fantasy or is there a reason dwarves couldn't successfully maintain cavalry? [Answer] # Dwarves don't have cavalry because cavalry is useless in their preferred environment. Let's take a look at history. ## Where does the cavalry excel? **On large, open flat plains.** Horses are large, heavy and require room to turn around. Footsoldiers can turn on the spot, rotating formation in place. Horses can't turn like that, thus they need a lot of area to manoeuvre. Because of that, **despite what films will show you, cavalry is useless in melee** - horses will be quickly wounded and riders dismounted, completely eliminating the advantage of having horses in the first place. **Cavalry fights by "shock and awe"** - horse and rider weigh a lot, and horsemen may have a long lance (preferably longer than pikes of enemy infantry). After picking up speed, charging cavalry drive lances into enemy, disrupting enemy formation, and nearly immediately crashing into incoherent enemy unit. **If enemy routs, they simply chase them down, if enemy stands despite loses, cav retreats to charge again.** And again. And again. That's how cavalry fights - never stop, always in motion. **As such, Dwarves have no cavalry for simple reason that cav is useless in cities, sieges, mines, mountains, swamps, rivers, forests or any location which isn't kilometres of flat plains.** Since Dwarves usually are portrayed as not just fond of mining, but actually living in underground cities, cavalry is not useful for them. Their environment favours heavy infantry (light infantry isn't useful for Dwarves for pretty much same reasons as cavalry). Anyone who tries to take over their mines or cities, needs to fight on their terms: in cramped tight mine shafts, dark and cramped cities or built over caverns. Because of that, only use Dwarves would have for cavalry is for offence. If Dwarves tried to invade plains for any reasons, they would need cavalry, but usual portrayal shows Dwarves as either isolationist, or living in mountainous area. Overall, depending on portrayal, Dwarves have literally no use for cavalry and little use for archers, crossbowmen and light infantry (unless they live in mountains and partially under, partially on surface, then they would have use for light infantry and archers or crossbowmen). Optimal heavy infantry weapon depends on details: Dwarves living on and below surface, would certainly have a use for pikes (pikes work well in tight formation), but living entirely underground makes pikes too cumbersome, turning attention to short weapons with anti-armour properties: staple [warhammers](https://en.wikipedia.org/wiki/War_hammer) and picks ([or Horsesman's picks, just without horse](https://en.wikipedia.org/wiki/Horseman%27s_pick)) or perhaps [maces](https://en.wikipedia.org/wiki/Mace_(weapon)). Short swords, like Gladius used by Roman heavy infantry, would be be very useful if apart from each other, Dwarves would fight underworld beasts which don't wear armour - short swords are especially effective with shield and in tight formation where short length is an advantage (long sword would be cumbersome in tight melee) but compared to warhammers, swords trade anti-armour properties for versatility. # As such, Dwarves have no cavalry for simple practicality: it's useless for them. All in all, lack of cavalry, light infantry and archers is perfectly logical. Staple weapons are logical too. What isn't logical, is surprising lack of shields. Common image of Dwarf doesn't feature shield which makes no sense to me - shield and one handed weapon is an excellent combination for heavy infantry fighting in tight formation. # And here, for some elaboration of concepts, with images. ## Why I say that pikes could be useful? [](https://i.stack.imgur.com/14vIt.jpg) *You want Iron, punk? We have it right here.* This image shows Macedonian Phalanx. Imagine something like that blocking the main entrance to the cavern. Or blocking the only flat passage through mountains. Rocky walls to your left and right, steel wall in front. Phalanx doesn't manoeuvre because those pikes ARE long but is excellent at spearing anything that tries to take it head on. If Dwarves live partially on ground, they would have use for this formation, even if they live in mountainous area, because you could block off bridges, tunnels or passages - but this would be the only function of this formation. I imagine speardwarves would be regarded with special reverence as first line of defence - protectors of mines and cities who never back off, blocking entrance with piling up enemy bodies. Keep in mind that it would NOT be main force. It's extremely specialised, but very good at doing what it's specialised to do - blocking the path. Other types of heavy infantry would handle fighting on slopes, in cities after enemy breaks through etc. but a unit or two of those would probably serve as first line at the entrance. Perhaps speardwarves would actually carry swords or hammers and simply drop the spears to convert into ordinary heavy infantry if situation demands this. Replace with halberds for much better manoeuvrability, late medieval look and ability to handle rough terrain at expense of reach. [](https://i.stack.imgur.com/9dsVg.jpg) *That's Pope's Swiss guard. This guys might look silly now, but that's because they retain their ceremonial look. Church after all loves ceremonies. Back when Pope started hiring them, they meant business, Pope started hiring them specifically because they meant very serious business.* ## Shields at 70% and holding *Shield wall is a very old concept.* [](https://i.stack.imgur.com/McvZx.jpg) *But it just keeps showing up.* [](https://i.stack.imgur.com/4v6l2.jpg) *Again...* [](https://i.stack.imgur.com/Z7uTj.jpg) *...and again.* [](https://i.stack.imgur.com/GFsWK.jpg) *Ok, I cheated a bit, 2 last images are the same thing: riot police.* Shields walls are great in melee. Close range, packed space, short weapons which are easier to operate in such crowd. It even provides nice protection from arrows. So, what are the drawbacks? Because it lacks spears, it's very vulnerable to cavalry (if you add spears you get Phalanx and lose the flexibility). It's also very vulnerable to firearms, so I guess shield wall wouldn't work so well if your world has significant numbers of battlemages. But if there's no cavalry and shields are enchanted against fireballs, this formation of heavy infantry will be very hard to crack in cities or passages and can work quite well in open terrain. Historically, shield wall beat the phalanx through much better flexibility, which is why I said that spears would be useful but only in very specific tasks. I imagine that main Dwarven fighting force would be heavy infantry utilising shield wall, and either anti-armour pick or generalist sword. ## [What does the light infantry even do?](https://en.wikipedia.org/wiki/Skirmisher) Light infantry exists to chase off archers and screen heavy infantry. Kind of like infantry version of cavalry. Not very useful in direct engagement, but loose formation makes them hard to hit with arrows. Archers would often stand in front of heavy infantry, and retreat behind, just before enemy infantry gets close. Task of skirmishers is to run in front of heavy infantry to threaten archers while heavy infantry marches on. Skirmishers would often have javelins to throw at enemy before retreating and letting heavy infantry do the fighting. Later on, light infantry could try to run behind enemy formation for a flanking attack. This formation wouldn't be useful in caves, mines and cities, but would be useful in surface part of Dwarven homeland. Unfortunately, shortness of Dwarves is a problem hard to overcome. I imagine that perhaps they would employ human mercenaries, or let some human villages exist on their land, specifically to have a source of skirmishers for surface combat (compare to [Janissaries](https://en.wikipedia.org/wiki/Janissaries) - Christian slaves, taken away by Ottoman empire at early age and trained as elite infantry). In this scenario, Dwarves would pretty much use human skirmishers instead of cavalry - good enough at screening main force, and can always be re-equipped for underground fighting with standard dwarven tactics. [Answer] **Battle is done from below.** The natural dwarf instinct is to undermine and strike from below, burned into the collective consciousness of all dwarves by millennia of tunnel warfare where to be above your enemy is to be vulnerable to all manner of painful attacks. A rider on a horse (or bull, or war-schauser) is elevated above their foes, which directly contradicts the dwarves doctrine of 'low is strong'. This philosophy is borne out by the Dwarven fondness of axes, weapons used to strike at the root of an enemy and literally 'fell' them. Dwarven strength and endurance also rewards Dwarves being rooted in one place, and a low centre of gravity, ridiculous resistance to being pushed around and massive ability to withstand heavy objects falling on them ensures that a company of Dwarven pikemen will not only be able to stand against a mass cavalry charge but in many cases will be below the effective striking range of even heavy cavalry units, meaning that any kind of cavalry charge against a dwarven army is pretty much doomed to failure. Even the most successful flanking manoeuvre is going to be rapidly curtailed due to the fact that pretty much every dwarf is at exactly the right height to stick his shovel in your horse's knee. The combination of a preference for striking from below and the utter uselessness of cavalry charges in Dwarven warfare means that the lack of cavalry is mostly a decision driven by what Dwarven commanders see as common sense. Why waste time, food and effort in rearing and training horses when you could instead raise more soldiers/miners/haulers? ***Addendum:*** Prompted by a comment from above: The dwarves are master diggers. Horses do not deal well with falling into ditches. Any battlefield that the dwarves can occupy for even a short period of time can be assumed to be riddled with terrain that will be incredibly dangerous for horses and riders (concealed pit traps, tunnels with near-to-collapse roofs, spike filled ditches) but absolutely fine for the far more earth-wary dwarves to traverse. Dwarven commanders know this, and have never even bothered trying cavalry charges. Again, Low is Strong. [Answer] **Use animals in Warfare? That'd be cruel! War is for Dwarves who've earned the right to battle.** It's a cultural thing. While humans and even those grubby elves ride horses into battle -- and even train warhorses -- the Dwarves regard those as both cruel and cowardly. War (and drinking) are serious business, best left to professionals. Of course, dwarves have horses, even some large breeds for plowing and pulling wagons. As has already been described by another poster, the dwarves have their own food production, storage and economy. Usually, they're more shepherds than cattle herders, and grow more barley (per capita) than any other known race. However, their agriculture is mostly in small fields, not heavily mechanized. Though some {relatively} young-Turk dwarves are looking into changing that, with their newfangled steam inventions.... [Answer] Horses are graminivores meaning [horses are grazers](https://hippologic.wordpress.com/2016/06/17/facts-friday-horses-are-grazers/). Horses actually develop health problems if they don't eat enough raw fiber (hay, not oats), and their stomachs are relatively small. The Dwarves would have to maintain a large area of grassland to feed them because horses eat all day long, and they happen to be picky eaters. Based on typical Dwarf terrain, I'd expect goats (and maybe sheep). They are less picky eaters and love climbing on rock cliffs. For pulling carts and wagons, they would prefer [donkeys which are stronger and smaller than horses](http://www.mikesdonkeys.co.uk/facts.html). Donkeys are also independent thinkers, less skittish than horses, and will protect livestock from dogs and wolves. Overall the temperament of donkeys seems to align more with dwarves, and I could imagine dwarves considering donkeys the superior animal. Donkeys can also be saddled, but it is a different saddle from horses because their backs are a different shape (this might address some of the other answers involving a dwarf's difficulty in riding a horse). [Ancient cavalries](https://en.wikipedia.org/wiki/Horses_in_warfare#Tactics) were like the jet fighters of their day, fantastically expensive and able to cover a long range in a short period of time, great for a surprise attack but they weren't the brunt of an army. Chariots are useless in the high mountains, and I suspect dwarves aren't exactly invaders or raiders (certainly not nomads), preferring instead to stay in their mountain kingdoms. They might keep a few horses as status wealth or possibly to stay in communication with other distant tribes or to increase the range of scouts on reconnaissance, but a full cavalry is probably just not their style. [Answer] All great answers, and I would just like to add that just because there is a possibility that dwarves might find themselves in a battle where having cavalry would be an advantage, doesn't mean they would use them. By then, they would not have a tradition of using cavalry. Unlike (say) humans, they wouldn't have a large pool of decent horses to draw from, built up from years of breeding and conditioning by a long-running culture of experienced horse... carers/breeders(?). Neither would they have a tradition of riders who have inspired young soldiers to be the best horsemen they could be. For example, you'd probably never see a joust at a dwarven fair. All of these would mean that if they did field a unit of cavalry, it would be one of inexperienced troops on poor to mediocre horses... So what would be the point? [Answer] I agree with the other posters that horse cavalry would be useless in a traditional dwarven stronghold. Ram, bear, etc cavalry have problems as well. When you’re in a tunnel, there is no practical way to get a bunch of dwarves and mounts up to speed. They would get in each other’s way. **What about centipedes?** Start with a normal, cave-dwelling centipede. Through evolution or magic, make it 3 feet tall and 100 feet long. Now you have a giant, poisonous, heavily armored (chitinous), dwarven battle train that can swiftly travel through narrow tunnels, cross moderate crevasses, and cope with extreme elevation changes. Take one battle-centipede, put 40 dwarves on it, and you’re off. The battlepede sprints through the tunnels with ease. If enemies are encountered, the heavy infantry dwarves hop off. Crossbow-dwarves and clerics remain mounted if there’s enough height in the tunnel to make an elevated platform useful. Heavy infantry moves foward, and the battlepede itself provides backup. Alternately, use the battlepede as a a battering ram. If the enemy doesn’t have a pike formation in front, then full speed ahead. The battlepede mounts a one-creature cavalry charge, smashes through the enemy formation, and as it travels through the enemy formation the still-mounted dwarves swing axes at any enemy they can reach, preventing the enemy from approaching the battlepede from the sides. **Bibliography:** I must offer thanks to Planet Earth II: Jungles. I watched it last night. Insects were featured prominently in this episode, and the railroad worm got me thinking along these lines. [Answer] I guess that the answer is to do with the idea that they are troglodyte miners, and therefore would not have the facility to raise and train mounts. If there were some sort of cave-dwelling domestic species, then they could definitely have a cavalry. The one thing that always gets me is that almost all modern representation of Dwarves makes them Welsh; not just their accents, but with celtic physiotypes, culture, and so on. **Edit** A quick image google shows Dwarf cavalry on: Badgers, Sheep/Goats, Bears, Pigs, and Ponies - so it's not exactly unknown for Dwarvern cavalry, right? [Answer] I think this is a much broader problem than just what's being asked about. Now, it's true that dwarves are fictional high fantasy beings, but some facts remain true across the many mythos they're found in. 1. Underground cities 2. Short and stocky 3. Proud, bordering on arrogant 4. At odds with Elves 5. Self-sufficient enough to have their own cities (first point) and trade with other dwarven cities (assumed) and some Humans settlements (assumed) 6. A love for ale, beer, or whatever alcoholic beverage is most common throughout the world they inhabit Based on points 3, 5, and 6, the following conclusions can be extrapolated. 1. They do not trade for their ale--they wouldn't depend on 'lesser, surface-dwellers' for something they drink that much of. 2. They do not trade for their food--same argument as above. 3. Extrapolating from points 1 & 2: They have the means to grow their own food, and process it to make whatever foods/drinks they enjoy. And can do this efficiently enough to sustain a city or multiple cities. That leads me to believe that them having mounts isn't that far fetched. I mean, think about it. Underground CITIES with those short legs? They'd either need mechanical transportation, or draught animals to haul the rock, ore and coal up from the depths--they certainly won't be doing that themselves. And travelling long distances? No proud warrior would do that if they can tame a beast to do it for them while they sit high upon their perch and leer down on lesser beings (being dramatic, but every race will have an a-hole that thinks like that). Now, I've googled Dwarven Mounts. I've seen pretty much what I'd expect: goats (mountain rams), bears, wolves, and mechanical transport. Goats/Rams living high in the mountains without too much trouble, so they are a logical choice. They'd just need to be selectively bred for size and back strength. Bears need to be selective bred for tameness (unless they enjoy breaking a bear or just riding them wild--which I seriously doubt). Wolves are more of a problem--they'd need to be bred for size **and** tameness, which would make them a lesser choice. Then again, Dwarves are stubborn folk. Give them a mountain, they'll make you a city. So give them the wildlife of their home range, and trust that they'll make something of that sad lot, you mark my words ;) [Answer] As others have pointed out, cavalry was used vary sparingl in warfare, only in certain circumstances that Dwarves are unlikely to find themselves in. It's worth noting that the primary purpose of horses in warfare was (in many cultures and eras), about moving infantry and supplies over long distance quickly, without tiring them out. Dragoons would ride to battle, and then dismount to fight. Dwarves, typically renowned for being able to travel long distances and carry large loads with great endurance, would not benefit from horses in warfare to the same extent as frailer races. [Answer] Was originally written to be a comment, but given no answer touches the topic, I'll post it as an answer. In short: > > Dwarves lack cavalry because they lack the relationship they require with the horse to do so. > > > Heavy Cavalry is quite the evolution to arrive at and how ingrained it is in our heads reflects this. For heavy cavalry to exist and be at it's most effective, the rider-mount relationship cannot be neglected. Horses aren't machines, they are alive and have as individual/unique personalities that any human has...this includes fear and hesitation. Training and the development of discipline is the counter to this fear and this includes not just the rider, but the mount as well. It's actually hard to find the 'first horse reference' in history...they are as linked to human history as humanity is. They were active in all parts of our lives and not simply war...farming, transportation, friendship, construction, and nearly any activity we undertook. This has resulted in a relationship between human and horse that is pretty much unparalleled in nature...they seek us and our companionship. This relationship is horribly understated as it's ultimately the reason we can use them as heavy cavalry. Elephants are larger, more powerful, and by a quick scan of numbers superior to a horse. However, the elephant is a wild creature, and you cannot teach discipline to a wild creature. That results in things like this (posted as a comment to the OP) en.wikipedia.org/wiki/War\_pig Elephants can and will panic : "Procopius, in History of the Wars,[6] records that the defenders of Edessa suspended a squealing pig from the walls to frighten away Khosrau's single siege elephant in the sixth century AD.". Kinda a funny situation, but ultimately there really is no training that would ever have this elephant overcome this primal fear. And here is where a horse changes the entire equation...our symbiotic relationship with them has developed to the point where we can teach them discipline, and more over, teach them to overcome fear. For our Elephant above...a single squealing pig can cause a feeling of fear and panic. This is an instinctive fear that we all experience in one form or another...but the elephant can't overcome it. A camel, by smell, inspires fear in a horse as a natural reaction not too different than the elephant feels about a war pig. However, through human assistance, a horse can overcome this fear (pause for a moment on that one...the relationship a horse has with us has developed such trust that it can overcome an instinctive fear). In terms of discipline, this puts horses on an equal footing with the rider on it's back and allows it to function in war. I think it's a fallacy to suggest other species have developed this relationship with horses. Dwarves live underground. A several century relationship with horses is not possible in their day to day life. To a Dwarf, the horse remains wild. Can they use them? Sure, toss the dwarf up there and tell em to hang on. Will the horse instinctively trust the dwarf enough to overcome it's own fears and learn discipline? I say no, they are not core to the dwarves society as they are to ours. [Answer] The strong points of cavalry are: * Speed * Mobility * Impact strenght This rules out using ponies, as they would always be inferior to war horses having less mass, lower height, lower speed and lower mobility. You might think of jockeys, which are short and ride normal horses, but keep in mind that jockeys in a race don't have to hit with swords or maces around them, therefore don't need a firm hold on their ride. Just compare a cow boy [](https://i.stack.imgur.com/I1Gw7.jpg) with a jockey [](https://i.stack.imgur.com/HPyqt.jpg) and see how big is the difference in their legs embracing the horse. That will play a key role in keeping the rider on the mount during a fight. [Answer] I would say because they are short. In your answer you mentioned that jockeys are small and that people fought on elephants. War horses were much larger than a racing horse. But still relied on the rider being the dangerous part with either a sword or a lance. Having a small horse with a small rider may not scale in the same way. Elephants were used because the elephant was the weapon using it's strength and weight to crush soldiers. A horse could not do that effectively and needs a rider to attack of it. Elephants were also used to put ranged soldiers on top like cannon and archers in a defensive structure. This could be more suited to dwarves but another trope is them not excelling at ranged combat. Someone mentioned they could ride wolves, but carnivorous are unsuitable for warfare according to another worldbuilding thread on the subject of bear cavalry. I Can't find it but I think in short they would be too hard to feed. [Answer] One important point is that horses were not used mines because they rear up when frightened, as into the ceiling of whatever tunnel they are in. Mules do not, which is why they were used for extra "mule power" in mines. Mules would live underground for long periods of time I believe, if properly fed. They didn't leave the mines like miners on a daily basis as far as I know. [Answer] Simply, I think, they have too short arms. Imagine what happens when a dwarf gets to sit on a horse. He's got too short of a radius for attacks. Dwarves are heavy warriors (for me), also. Two handed weapons are not a good idea when you have only a small area for making moves. Try to imagine that warrior on a big horse. Of course they can still ride on ponies (there was a scene in the *Lord Of The Rings Movie* (no I didn't read the book)), but smaller animals start to make this idea too... risky. You know what i mean. [Answer] Reading through this discussion has proven incredibly educational. It made me wonder: perhaps using boars might work? Now, I know boars are about as open to taming as a rabbit to celibacy, but let's say that problem is solved - my preferred solution would be a breed that lives on the slopes, the rocky valleys, and generally in colder, dryer places, including near-surface tunnel systems. This breed developed quite a sense of direction and memory so that it could reliably navigate its environment. Initially, dwarves used them as guard dogs for their homes and livestock, so they bred them big and strong. This eventually escalated to the point where riding one didn't seem like a bad idea, which in turn led to the breeding of "battlehogs" and "speedpigs". The former was bred for pure strength and endurance, while the latter was more about, you guessed it, speed and endurance (because dwarves and lack of endurance just doesn't mix). Speedpigs would be for couriers, scouts, explorers, hunters, and the like. Battlehogs, on the other hand, would be used to deliver heavy infantry to battle where they would dismount (a non-issue since boars are to horses as dwarves are to humans: much lower center of gravity), then get in the thick of it, with their armoured boars in tow. They would be used as shock cav/troops against tightly packed infantry formations, preferably in the rear, erupting from concealed positions in a mountainous area (imagine a couple dozen of these rushing out from behind what you thought was a solid rock wall, which may or may not have exploded in your face). Depending on the situation, they can be an unexpectedly delivered anvil for the heavy infantry hammer, grinding all in-between into thick, red paste, or as the usual shock and awe tool that can retreat to a safe location to strike again later (the route to which is probably trapped). The thing that is easy to forget as humans is that until airplanes became a thing, we thought in 2D when it came to combat. However, dwarves, who live underground, always have and always will think in 3D. To them, fighting purely on an open field is all sorts of stupid. So when using cavalry, they wouldn't think in terms of "big battering ram swinging on a big open place", but "relatively high-speed dwarf delivery system". They would 100% acknowledge the benefits of speed and mobility in battle provided by cavalry but they would use it on their own terms, their own turf. Which is also what makes dwarves such a tough nut to crack: it is no stretch to say that one if the mightiest weapons of war is the shovel (just ask the Gauls about that time they thought they had Caesar caught in a pincer), and every single dwarf learns how to use one and for extended periods of time. In defense of their home, women and children can pitch in making trenches, traps, tunnels, without ever going near combat, and that is assuming they didn't make any as a hobby, part of training, or sheer boredom. Which then leads to my last point: military intelligence and its acquisition. When you enter dwarven territory, you can't trust anything you see. The ground beneath you could be a trap of a dozen kinds, the trees could be hiding snipers (or even bombers if there's the tech for it), any vertical rock face can crack open, any innocent-looking cave can become a tunnel exit, any valley or path can become a death trap in so many ways. This is exactly the kind of environment where you want the speed cavalry can provide, so that you can harass the foe to the point where your main force either needs only mop up or just show up to accept surrender from the enemy general. All of this rests on the dwarves' understanding that a battle begins not when the opposing forces clash but when the intent to harm first sparks. Then it is time to plan, to prepare, to carefully craft the demise of the foe, so that when battle is joined, it is already won. [Answer] To draw a bit more on classical history, consider the Macedonian army. It comes from a topology that would be familiar to dwarves. The Macedonian army was used by Alexander the Great after his pops, Phillip developed it to a high degree of excellence. Their signature feature was the pike phalanx. Their best cavalry was a small unit of men dubbed "Companions" a sort of general's bodyguard on steroids, like The SS division Liebstandardt in WWII which started out as the the Fuerher's (sp?) bodyguard but morphed. A Pike Phalanx does badly on rough ground, mountains are rough ground, so why does a mountainous kingdom excel at Pike Phalanxes? Because battles for mountainous regions are decided on the restricted flat areas that give easy access. THAT is GREAT territory for a phalanx, flanks can be protected easily and frontal assaults are what they do. Keep in mind that Pike Phalanxes tend to annhiliate spearmen due to the extra length of the pike, and do well against other infantry side arms unless the wielders are HIGHLY trained AND experienced. Even then the best solution to beating a phalanx was to disrupt it, or tempt it to advance onto broken ground, which naturally disrupts the wall of pointy sticks presented by the Phalanx. Dwarves would excel at this but for simple physics. Holding an 18 foot long sarissa (pike) works best when you are tall. It gives you leverage for the pike which is naturally held in a downward sloping grip. You gotta be about 5' or more to hold one up very long. So, yeah, not so great for dwarves. Ogres on the other hand make FORMIBLE pikemen. I favor them heavily in my fantasy armies. :) So to answer your dwarf questions. [Answer] Traditionally in games and such Dwarves, if they ride something, it's wolves, donkeys or ponies. It just depends on your setting. If they don't travel or take dominion over large swaths of land then they don't need them. Same with drows (dark elves). Of course these can vary from setting to setting and franchise to franchise, but generally they don't wage large war on top of land anyways. As for what would their cavalry eat, you could also ask the same question about them as well! In most settings the vast underground cities of them offer no traditional food sources - so whatever they would eat, their wolves would eat. In most contexts they are shown as eating lots of meat and drinking beer, which would indicate that they have some kind of livestock anyways and access to grains to make the beer from. Usually in most worldbuilding dwarves are used to fill the role of the stubby strong species and usually in alliance with some other species that takes care of the fast units. [Answer] **Cavalry or mounted infantry/dragoons - there's is a difference** Depending on the terrain you imagine Dwarves live in there's no pressing reason for them to fight on horseback. If they live on plains? yes obviously there is an advantage but Tolkien (and most writers ever since) associate them with hills and mountains etc. However even if they don't live in kingdoms etc that extend out into good 'horse country' there's no logical reason why they can't use mounts to greatly increase their mobility by riding to the location of a battle before *dismounting and fighting on foot*. This is a well established military tactic. Not to mention there's no reason why Dwarves wouldn't acquire/become familiar with horses, ponies, donkeys (insert your favorite beast of burden here) via ordinary day to day commerce with other races and having done so use them accordingly. Which means when war is declared they are going to use them where and whenever they see it as advantageous. ]

[Question] [ Imagine a world where every time you wake up you wake up in a randomly selected body from among the bodies that were asleep at that time. There are some limits—the body should be in at most a roughly 5 mile radius of the body you went to sleep in. People maintain their memories, personalities etc when swapping bodies—only the bodies change. Could such a society function? It seems that cities on our current scale could not—since so much (jobs, rental agreements, etc) depends on relationships that would be hard to maintain with people swapping bodies so much. Perhaps a small society of maybe 30 people on an island could—since they all know each other and could maintain relationships, despite people hopping about. The question: what is the maximum size society that could function under such an arrangement? What challenges could be overcome (and how) to reach such a size and what challenge would be the fundamental limiter preventing any further growth? --- EDIT These clarifications mostly exist in the comments, but I'm putting them here to have them in one place. * Shuffling begins at birth and ends at death. If you shuffle into an old body that dies while you are in it, you die. If someone dies in their sleep, the mind that dies is selected randomly from the people in that region who were asleep at that time. * What determines shuffling is sleep: when someone awakes they get a random body from among the bodies that were asleep at that time (in their region). Time of day/night doesn't affect anything. * It is the minds/spirits that move during the shuffle. The body wakes up where it went to sleep. * Society developed in this way from the beginning. The question is not that if our society became like this could we cope, but if a human species had always lived with this context, could that species survive and how big could the population hubs be (e.g. small tribe vs town vs city). [Answer] Society as we know it certainly could NOT function if this were the case. A couple of issues that immediately occurred to me, even more fundamental than retention of property (and retention of property is huge!): **Children would be extremely dangerous to be around!** Adults are significantly stronger than children. Imagine if a mother and her one-year-old son happened to swap bodies. Suddenly you might have a one-year-old's personality and (lack of) wisdom in the body of a grown woman, and the mother in a helpless and weak body. The woman-bodied child might accidentally crush the child-bodied mother, or fall into a fire, etc. The mother would be physically unable to prevent these problems. Or imagine an angry four-year-old, still smarting from being told it was naughty to hit people, and suddenly in his father's body and capable of actually hurting people! **Power could be abused forever** Assuming the human race could survive at all... If proximity and simultaneous sleep could potentially be used to swap bodies, relative immortality would be possible for some. Enclaves could be established where only those of a moderate age and reasonable health were allowed to sleep, so the only body you would "risk" waking up in would be of acceptable quality. As someone "aged out", they could kidnap a young body, and lock the young body and the aging individual in an even more isolated cell for sleep-periods. When the locked-up kidnapped body can deliver the right password-type proofs that it's got the right person in it, you know the transfer is successful, and the old body may be eliminated. Nothing like the world we currently live in would be possible. [Answer] I actually think large cities could function but they would be very different to ours. Your house would be near a cluster of sleeping rooms and would have a password entry since keys are not going to work. Clusters of sleeping rooms are at least 5 miles apart and probably need some excellent public transit options. That is probably the hardest part of making a city and is probably going to have assigned sleep times to help allow reuse. People would be assigned to these facilities based on age, gender, physical condition and so forth so you keep a similar body at least. There would be numerous government centers that would give you a daily ID after you give a password so you can have an identity and legal agreements based on that. You have to show it to get into your job and you have to put its info into your phone to receive calls. There will be huge penalties for sleeping in random places or at random times, as that threatens the system. Children will be communal. Since no one really has DNA that is theirs and letting children swap with adults would be a disaster children will be raised in group facilities that are at least 5 miles away from any other places people might sleep. Being a parent will be a job like any other since little kids keep swapping around getting attached to any single one is harder. Prison could simply be being stuck in disabled bodies, no matter how evil you are if you are paralyzed you aren't going to do much damage. Coffee and other stimulants are practically mandatory if you are feeling tired while out and about so they will possibly be government dispensed. Health care is also going to be communal since one person's illness is now literally everyone's problem. Immortality is possible and that changes things a lot. An old person just needs to set it up so they sleep with young people and boom they are young again. This could be the worst crime possible or a totally legal thing that's expensive but either way it would allow all kinds of radical changes to the world. Either way these cities could possibly have the same people in charge forever and that could help with stabilizing things against the chaos this causes. [Answer] **Class Inequality** You would likely end up with sectarian societies, one of which would be elites who create a "gated community" city that would exploit the labor of the lower class, but who would prevent those classes from accessing their community. **Religious Implications** If their society is anything like ours, there would likely be monastical living situations based on a religious compulsion. People who shared these values would likely live as monks and nuns, since sharing bodies between sexes would be considered improper. Also, if there was something resembling a patriarchal power imbalance, men or women might not want the other to share in their experience. **Values** This society, like ours, would be drawn towards empathy if not for the constant insistence on segregation of experience. Cultures that are empathetic would be ones that perhaps are not as technologically advanced, and therefore unable to travel the 5 miles to and from resources provided by others. The value of the individual would grow as technology advanced far enough to allow it to do so, and the value of community would be inversely proportionate to this. **Loophole** You could consider creating the condition that the "size" of a person's mind (their experiences, intelligence, etc.) only transfers to a suitable host with a brain that allows for the same level of functionality. This would solve the problem of an isolated family. The mother and father might switch minds regularly, but the children might not until they had reached a certain age, and upon approaching adulthood, could possibly then switch with the parents. It would at least prevent a fetus from switching minds with its mother, which makes sense since a fetus' brain is not physically developed to the point of sustaining an adult's mind. This condition would also create some interesting characters--geniuses or those with broader experiences might be quite lonely waking up in the same body. The consistency of their physical appearance might make them natural leaders. In this scenario there would most likely be a group of leaders who wake up in different bodies but are consistently the same 10-20 people, revered for their experience and intellect. A twist to this story might happen when someone who doesn't consider themselves very intelligent suddenly finds themselves awake in the bodies of one of these elders. [Answer] **Answering this from the perspective of your world will be fun** It's easy to fall into the temptation of telling you about all the problems *the real world* would have if random body swapping suddenly began to happen. Let's not do that. let's assume that your world has been this way since the moment your sapient species became… well… sapient. This would be nothing new at all to anyone. It would be a fact of everyday life. **Cooperative Breeding** Your society would most likely develop a behavior we humans call *[cooperative breeding](https://en.wikipedia.org/wiki/Cooperative_breeding).* This happens when (a) the young of the group are cared for by all parents in the group and/or (b) when there are multiple mating males and females (no monogamy). From a modern legal perspective, it would be incumbent on whomever is psychologically in a household to care for whatever youth are found in that household for the day said parent is in it. *A species that developed this way would certainly develop a genderless perspective of individuality. Yesterday I was female, today I'm male... whatever.* **Individuality would serve society** It is obvious to me that your society would need to embrace communal living, meaning that the resources of all are available to all. We humans have basically proven that we can't live that way, but where cooperative breeding becomes a requirement, socialized education, health care, provisioning for the child (housing, clothing, food, etc.) becomes mandatory. This isn't to say there wouldn't be individual achievement, or even individual acquisition of wealth. Bank accounts have always been controlled by account numbers and pass codes. What would change are laws mandating that wherever you show up the next morning, you're obligated to continue with that household's efforts, whether they be repair work or anything else. *An astute observer will figure out that what I just described would be incredibly complicated. But, legally and socially, it could be made to work. Think of it as, "all your production goes to the state and we'll give you an allowance commensurate with your productivity and value to society." In other words; smart, educated, self-motivated people have a bigger allowance than those who are not.* **Almost no housing would be private** In fact, I could be convinced that no housing would be private. The law would quickly change to reflect the fact that someone who was last in a beautiful, well-maintained home who suddenly found themselves in a wreck would choose to "let the next person deal with it." Wrecks would become condemned very quickly. Thus, no private choice in housing. Or transportation. Or almost anything else. **People would live very close to where they work** Employment would become password-based. As in, "I'm Bill Murray and I'm you're plumber! My password is Oscar-Delta-Zebra-Niner-Five-Seven-Seven-Epsilon-Eight-Zero-Alpha." This would require keeping great books with one person having the passcode to the door. Which is all doable with modern tech, but how would the medieval folks do it? That's a good question. **The society would be ultimately trusting, with betrayers paying the ultimate price** Society could not possibly work without trust, especially early when technology couldn't make up the difference. And the only way that could possibly work would be with instant and merciless capital punishment. Though many might disagree with me, a society that can't trust fingerprints or visual identification (you look like Fred!) can't waste time with people who won't work with the community. It's not punishment — it's removal, like cutting out a tumor. **There is a weakness...** It would be very difficult to get anything done long-term. And by long-term, I mean two or more days. If your project is dependent on strong backs, then you need to re-hire your labor force *every day* because whomever the strong backs were yesterday, those bodies don't remember being the strong backs today. Long-term planning (which is a *big deal*) would need to be carefully planned, incredibly well documented, and patiently completed. It could be done, but it would be slow. **And finally, death...** Your species would develop a behavior of segregating themselves by age. If you remember the old sit-com *Dinosaurs,* you should be thinking "[hurling day](https://www.youtube.com/watch?v=APXLid0D584)." Without this segregation your society has massive problems (which others have pointed out). However, from the perspective of a species, it's more likely that random body-swapping is something that wouldn't start before puberty and would stop in late middle-age or early senior years. So (to reflect my personal morality), 0-17 = no swapping. 18-60, swapping. 61-? = no swapping. Or, the swapping process is bound by age (you won't swap with anyone who isn't +/- 2 years your own age). **Conclusion** I think this could be made to work with any sized society. I do NOT think humanity could ever be made to believably work this way. The social upheaval would be catastrophic. But a species that developed this way. Yes, I can see that happening. And it would make for a very interesting place for humans to visit. [Answer] Assuming the switch only occurs while you are asleep, and assuming you want people to have private property it could go something like this. > > Me and my neighbors all have a secure sleeping pod on the side of our > house. I go to sleep in it every night because I know that when I > wake up I will be in another pod and someone else will be in mine. I > made sure to put all my valuables in my house before I went to > bed. From the pod, the stranger will wake up, but they can't get into > my house or access my stuff because the pod is not in my house. > Usually they politely exit the pod and take a ride share back to their > house (ist just a few miles). > > > Every new body has its quirks, but I have been in thousands of bodies > before so I learn pretty quickly now. This one is very similar to one I was in last > month. > > > The touch screen in the pod I woke up in has the ride share app on it. I also call > for a ride. I pay the driver by telling him my account number. When > I get there my wife is waiting for me in a new body. I > don't really know what she originally looked like, but neither does she. I > greet her and verify her identity by using my co-name (a secret name > that is used only with another person or group) > she verifies her identity by responding with her correct co-name. > > > I have different co-names I use with different people depending on how much I > trust them. > > > I use my pin code to open my front door and get ready for work. > > > The kids are in a public boarding school. The school is outside the > city so they don't switch with any adults. The teachers sleeping area > is a few miles from the school. There are night time care-takers at > the school to help children. The caretakers never sleep at the school. > We Skype the kids during the week and visit > them during the day on weekends. > > > We don't know who our kids original parents were. They are not biologically > ours. And their minds are not from children who were biologically ours. > But we adopted them when they became old enough to be able to understand their > co-names. We had another child for a few months, but I think he was a bit too > young when we adopted him. One day he stopped identifying himself to us and > we never figured out how to find them. > > > I think this arrangement could allow a society to get reasonably big. But cities might be a little more spread out since you need separate areas for the children. I think that one major change would be that the use of memorized access codes or account info would be more common since physical keys or cards wouldn't be useable after initially waking up. Also biometric identification would be totally useless. [Answer] It would be very difficult for society to function correctly. Imagine jumping into the body of a diabetic,someone with peanut allergies or any number of chronic medical conditions that an be managed by those that know they have them and what to do about it. Randomly awakening in a body and not knowing that before breakfast you need to medicate or your new body will suffer serious consequences. Even something simple like eyeglasses without them a person may be unable to see properly, knowing where you left your pair the night before is important if your prescription is high enough. [Answer] Current society? No, but I think that this type of system would actually promote people to live very similar, structured communal lives. Imagine you wake up in someone's body, but that person didn't have any food in "his" house the day before. Now you go hungry, right? Suddenly it also dawns on you, how do you pay? Any physical paying methods would be on your previous body, and every time you go to sleep that would change again. This means that every person would make sure the basics of life would always be available nearby, if only because if they don't do it someone else might also not do it. This would also mean that going drunk before going to sleep would be frowned upon, and people might actually be arrested and chemically kept awake until they aren't drunk or whatever anymore for the sake of whichever poor soul has to inhabit that person. Communities would still be able to have their own houses and things, but the sleeping arrangements would all be located in one communal area. This way you know where you'll wake up, and after waking up you can move to your own house with your own things, live your life normally and then go back to the communal area's for sleeping. If this is how it's always been then monetary things might never really be invented. If it suddenly happens to our current world then we would try to use electronics to keep track of our money and to secure our homes. A memorized code can be taken with you when you go to sleep, the keys to your house and car can't. Younger people would prefer not to wake up in an old body that is about to die or might never wake up. It is likely that bodies in general are going to get tatoo's to indicate when they were born, and thrown into one large group of similar age. These groups will always go to sleep in one area, away from other age groups. This way the group as a whole will grow old and die. There will definitely be people who try to abuse it and go to sleep nearby a younger generation group. This can be countered through a set of standard questions that each group gets upon getting up (easier when computer technology comes around), to see if everyone is accounted for. If someone from an older age group has managed to get inside the body of a younger age group he won't know the correct answers to identify himself as a specific person from that group and a search will happen for the person who does have the correct answer, after which they are forced to swap back again. This communal thinking will have to stretch to everything, including children. If you get knocked up one day, you'll have a good chance you'll never even see your own pregnant body again! Children would have to be raised in communities as well, as there's no real telling who is the mother or father. The person who finds out if you got knocked up is going to be inhabiting it months down the line! [Answer] # Of Course We'll Still Function! [](https://cdn2.bigcommerce.com/server2100/da4a7/products/492/images/22/KEEP-CALM-RED-TIN-SIGN-WEB_large__61819.1291468243.1280.1280.jpg?c=2) No one has actually changed...not where it matters, anyway. Of course society will be quite different. You never know what you're going to look like in the morning, so neither you nor anyone else really cares. You don't know what your coworkers or friends or anyone else is going to look like, so such visual social cues will be nonexistent. You just wake up, say good morning to whoever is in the bed / sleeping chamber with you, dress in whatever clothes are locally available and go about your day already. Leave the existential breakdowns to the philosophers, because you've got to get downtown for that meeting / get over to the public works depot and sort out that issue with the rubbish truck / get to the shop and make the donuts. [Answer] Jack Chalker seems to think that it might be possible - he postulates a similar society in the second book of his *Four Lords of the Diamond* series, *Cerberus: A Wolf in the Fold*. His society is somewhat more controlled than most modern societies, and has a method of identifying a person *mentally* - that is, the mind that's in the body. In general, there are two classes of person - those that keep the same job regardless of the body they're in (i.e., the job stays with the mind), and those that keep the same job regardless of the mind that's in the body (i.e., the job stays with the body). Most white-collar jobs are in the first class; undesirable jobs, and (in his society) host-motherhood, are in the second, and it's rare for people in the first class to associate with people in the second (because what happens if a first-class swaps with a second-class?). [Answer] There would be no society, there would be no humans. My ears do not produce a signal your brain can use to hear, not without months of exposure for your brain to relearn to interpret the new signals. Brains are not interchangeable they have to adapt to processing the signals of the new body. Based on flipped/inverted glasses experiments it would takes weeks or months to learn the hear with someone else's ears or see with their eyes, in someone else's body you would have to learn to walk and even control your muscles all over again, if it happens every night the human population is reduced to a pile a flailing sacks of meat, unable to control their bodies well enough for coordinated movement and unable t o understand what their sensory organs are sending. billions would die of starvation or exposure. Within a few weeks of the first switch there would be no humans left. [Answer] The statement that society has always been this way puts a hugely different spin on this. What you grow up with is normal and a race that works like this will have no problem with it. But society will develop very differently from how human society did. We can consider how early societies functioned under these circumstances, as that will dictate how later ones work. Early societies were isolated clans, so it is likely that initially transference took place only within your clan. The needs of survival mean that early people didn't think about it or spend much time concerned with it. Personal property probably never became a thing, nor did monogamy. You might well keep the new mate you woke up next to for her body (her mind and personality are secondary) and who does the knife lying by your bed belong to anyway? Sense of self probably diminishes too, and since random personalities likely die occasionally people don't get attached to the idea of life. All property becomes clan property. Children become clan children, since the problem of figuring out which personality is actually responsible is far too complicated for a group focussed on survival. Fighting would be virtually unheard of within the clan. You might slap someone you disagreed with, but you would not damage a body you might inhabit tomorrow. Bodies would be considered common property, and the clan wouldn't let people mistreat them, either while inhabiting them or not. There would be no segregated roles. You wouldn't leave your most knowledgeable hunter out of the hunt just because she happened to be female today. Likewise nobody can use strength to dominate another person or group, since they might be the weak person tomorrow. Territories would be strongly defended. Conquest and slavery would be unheard of. You cannot keep anyone is slavery if you might wake up tomorrow in their physical circumstances. There might still be war, where one clan attacks another to gain possession of something like a natural resource, but it would probably be necessary to kill all the previous inhabitants when you did so. There would be no kings or power structures for the same reasons. Visitors would be limited to daytime unless well trusted because of the possibility of leaving with clan property, including but not limited to a valuable body which might be better than the one they arrived with. This would make trade extremely difficult. Ancient society evolves into networks of clans, separated physically to prevent intermingling but trusting each other well enough to allow occasional visitors for trade and similar purposes. In these circumstances it's hard to see how civilization evolves into large cities (even large by ancient standards, i.e. a few thousand people). This effectively prevents the imperial conquest phase of human evolution from happening. it's also hard to see how specialized labour can happen, which might prevent the rise of the leisured classes which give rise to scientists and philosophers. This along with trade problems might slow scientific and economic development. [Answer] While thinking about "how would it fit into modern society" is fun, what if we'll think about development of such species from ancient times? ## Ancient times (humanity begins) So here we are, small (let's say 4-15 person) groups who recivied souls (somehow). Which problems such group will likely face? 1. Bodies may vary. Yesterday you were able to go hunting, today you are much better at looking for babies and harveting berries. I have no idea about their psycology at that times, but idea of being genderless is likely: whatever, it is just process of creating children, no hard feelings. Monogamy is very unlikely too: it is not profitable for surviving anymore (if sex is still about biology and not souls, otherwise entire humanity will work different way starting from this point). This also leads to learning of everything known regardless of anything: person should be able to use any body at its max abilities. 2. Children problem. As other answers have pointed out, children are dangerous now. Let somebody wake up in their body and they are useless for a day. Let very young baby wake up in adult body — they are useless again but also posess a great danger to others. This could be solved by never sleeping at same time children do. Hopefully, your day still have around 24 hours and your fellow humans need about 8 hours of sleep everyday. In this case we can divide day into two part: 15-hours one for adults' sleep (exact time may vary, also different people may enter and leave sleep during it) and 8-9 hours when all adults don't sleep and children do. We also now have somebody awaken to keep an eye on your children to don't let them fall asleep. Moving into adult-time sleep may occur in specific age or when one is skilled enough to do something useful. This include some interesting rites tho… 3. Elders and deathly ill ones problem. Things turn out sad this time. When some body becames too weak it will be better for spiece to get rid of it by exiling or even directly killing them. But who will take it to die within? It could be one of that: random unlucky person, somebody least useful (good for spiece 2x) or some children. Why children you say? It will allow to maintain knowledge easily, without need to write down or even talk… and never develop speech nor modern society. We just hit dead end. Such society will exsist and will likely be found by researches in distant future ("Scientists have discovered group of persons whose souls must have seen 10000 years BC" - BBC from your world). So some groups decided to put only full aged ones in elders bodies and force them to go away to die. Reason doesn't matter — some randomy appeared rite would be enough. Also, rite to keep your todays' body in great form will be required because group will die really quickly. ## Before/medival ages Let's say at some point our last group develop speech and have to face an important problem: technologies became too complicated to be perfected by everyone and profession may require different body variations. What to do now? Easy and efficient solution would be to let different masters live in separated villages/towns where exchange of souls is impossible. In order to exchange stuff they will have to meet in some kind of special place like giant market where all kind of buisness do occur: it also may include some common education schools. Some persons who wish to change their lives may also sleep there to exchange bodies with others from different towns. However, it will likely be punished by others due to requiment to teach them again, if they aren't children (which now have a way to get body sutable for profession of their dream!). This model also may lead to some fun evolution where different towns develop their own different DNA samples (each town is a distinct population actually) resulting in specialized farmers, blacksmithes, miners and others, probably even ending in ones who differ *a lot* if this epoch lasts long enough. As for government, it is not very likely to have one (and much harder to have more than one). Wars would became something insane due to constant exchange of bodies. Such society will require strond punishment for betraying/cheating within one town, or it will fall apart. This require absolute trust at first, which potentially could be maintained on long term too. Religion would help a lot. And to our older problems: 1. Bodies may vary. Nothing pretty much changes. Everybody in town is married by everybody, everybody master the same thing. 2. Children problem. And we still have same solution. Other one is impossible until we have a way of isolating children from overwatchers (while keeping them alive). 3. Elders and deathly ill ones problem. And here we have some positive changes: elders from different towns may live in separated one, helping each other. While it is still doesn't seem so great, it is at least sounds a bit more accepable, huh? You have a great idea which nobody seems to implement yet? Well, we are in trouble here… This society is very stable and can change hardly: pesonality is not valuable here, congrats on building communism. It may last many centuries or even few thousands of years until somebody comes to change it… ## Technological revolution It is impossible to say how exactly will it begin. Probably, someday some crazy person finds enough followers on giant marketplace who agree to join him on everyday base is some crazy project like steam engine or something else which will knock the world over. I'm not going to describe it completely here (that would be interesting story to read for me tho), let's say that humanity *begins to belive into innovations*, and this means a lot. Some people begin to leave their towns to join new village of researchers… which probaly became rich pretty soon! ## Futher development There are some critical things which could change your society a lot: 1. Automated machines which can take care of children. They would allow to finally escape childrens problems and use humans much more efficiently. 2. Shuffle inhibitors. If somebody manages to invent them and produce in huge portions, they will be able to insantly overcome a lot of complications, making it possible to build stable group which could became an army capable of acting hightly organized and capturing cities with ease. This may lead to a very long way to something like our society either in case of war or making them publicly available. If last one don't happen, it is possible to survive within realtively small towns and without government: things like private property became impossible because you can't remember anything not guessable within reasonable time and there is no way to do 2FA. Of course, until you have 3. USID — unique sould ID. If there is a way to confirm that some body have somebody's soul, it becames possible to build all kind of advanced things we have. It will can not lead to any kind of war, making it possible to migrate into large low-trust cities where it is possible to mantain all kinds of property and access restrictions. People will likely have something like "house", place where they can enjoy their favorite private things like videogames, and public bedroom qarters, where everybody sleep. Rich guys may build houses in distant places, trying to keep same body for long time. Machines which can automatically take care of children and elders would improve situation too. As replication was never considered somewhat really private, when tech level reaches big hights making it possible to grow children from scratch without having sex, it will likely eleminate old way, especially if being supported by government. Everyone in cities will be entrusted with keeping their current bodies within reasonable state to keep every body healthy. Health will likely be tracked every bed exit/enterance, noting body vandalism and writing out fines from such souls. Medicine will be kept by government because bodies aren't private property at all. Ones who need long-time recovery could be moved into distant machine-operated hospitals as well. Non-mental contests will likely never became popular or even existent — it will seem clear for everyone that bodies is somewhat unimportant in their lives. Prisons will likely be distant machine-operated places as well — you don't wanna let criminals escape via soul exchange! As for elders, it is hard to say to which morality that society will attach. It seem reasonable to make criminals take old bodies to let good people use healthy ones. Overall, future doesn't seem to dark anyways. Body shuffle works nicely in two cases: 1. Small society with absolute trust. This is also applicable to space expeditions in modern word. 2. Big society with SoulIDs. So answer depends on ability to get SoulID: if you can, huge cities with modern technologies is possible, if not, small towns still can survive quite happily. If it is possible to inhibit body shuffle, result depend on when they discover it: it will lead to catastrophy in medival times but can be used in quite good ways if discovered in modern world. [Answer] **Vault 93** - OVERSEER'S EYES ONLY - example exposition: Good morning, citizen. Today you be inhabiting, [name], of sector number [#]. Your responsibilities will include but are not limited to: clothe, feed, and ensure the attendance of any students under your care, prior to 9am. You will report to work at facility [#] for [amount] hours. After which you will feed, launder, and otherwise ensure the health of family [name] of sector number [#]. Failure of any of these responsibilities will result in lower marks, and your next inhabitation will be less desirable to suit. Desirability is determined by exit interviews which occur just before bedtime. [Answer] My guess is that it will not work with our kind of minds, which needs years of teaching (in growing up, going to school, studying and so on) before being able to hold a good job. Simple jobs for many people would work but besides those simple jobs you need harder jobs, where training and study are important. But it would work with a community where the minds are like some animals which have a good working set of instincts and can learn on top of that. If babies do not need parents to feed them but can find enough to eat around the nest/home they can grow to become useful members of society. If you look at some birds, they have the basics of surviving from birth, learning from copying others when they see those do something smart. To get from a hand to mouth, gatherer (and maybe hunter) society to a farming (or herding) society will not be easy, but it might help when groups of people stay together and not mix much with other groups, so people are more likely to learn to invest in the future. Going from that to a more technical society and on to a mechanized and on to an industrialized society will be much bigger steps that they were in our world. A lot will depend on how much experimenters the people are, which is a decision you as writer has to make, and what kind of muscle memory (stays with the body) there is to build on what the body has done before. And how big the groups are, if your average swap group is no bigger than 7 people, you would be in the same body on average once every week, which would be good enough to encourage people to work for the future, certainly if it is a common future. But if the group size is roughly 350 people, you only end up in the same body (on average) once a year, if everybody swaps with everybody. My guess is that in the early developments, from just gathering to hunting or farming/herding, you need very small groups, basically extended families of no more than 10 to at most 20 people. For the further developments you need bigger groups but not too big, maybe a few small groups staying near each other but just out of swap reach, say 30 at first and going up to 300 in split groups, (still no more than about 10 to 20 for swapping) for getting crafts and early mechanical developments. Only when you have that level, you can work out whether they can start live closer (small towns/cities) with all the swapping or need smaller clusters for some age groups (called boarding schools in an other answer) or that society can develop in your kind of world in spread out villages (smaller groups.) What will help is if individuals usually have quite long lives and as such a long time to learn and share knowledge. [Answer] Not a complete answer but something I don't see in any others. If you are close to death, and have the resources for medical care, then you just get put to sleep. You have at least a fighting chance of waking up in another body before your old one dies. This leads to another question - if a body dies while asleep, who dies? The person who did inhabit it? But maybe they have been already assigned to a new body? If that's the case is there now N+1 souls hanging around with N living bodies? Does one wake up dead, or do they all wait for a body to be available, with an equal chance of getting reincarnated when the next body wakes up? That would lead to an eventual accumulation of disembodied souls as more people die in their sleep. [Answer] This is basically a recipe for living forever. People swap swap swap, but as long as your body doesn't die, you won't die. I can certainly see this as a society killing off their young(minds), just them being there providing new healthy bodies. You would have baby farms, far from populated areas, staff would not be allowed to sleep. Old bodies would go there and pickup a baby to take to retreat so far away from everything else, that there is only 1 swap possible. They go to sleep and now you have a baby in an old body and get rid of it and the other person lives on. [Answer] I can see it ending either in a good way or bad way Utpopia: The constant body swapping made everyone realize that we should strive to take care and love each other above all. No one should be left behind since that no one could potentially be you. War and greed end, everybody shares resources for the greater good. Humanity's efforts are focused on good things, curing diseases, extending lifespan, making sure everyone has a happy healthy life. The mysteries of aging, organ systhesis and intergalatic travel are eventually solved and everyone can live forever. Humanity spreads spreads through the galaxy. Dystopia: Criminal organisation leaders quickly realized that if they manage to gather a pity of healthy strong prisoners and only sleep in their vicinity, you would always wake up in a young body and be potentially immortal. After a wave of high profile kidnapping (high level athletes, models), Billionaire started offering vast amounts of money to healthy young people who would join them and had no problems ensuring their immortality without resorting to any illegal means. Celebrities and political leaders and other high profile people had no problem finding volunteers, their fame guaranteed that. For the rich but not super rich, it would be more difficult to be immortal through this process but not impossible. Gradually society changes and everyone's only goal is to find a group to guarantee their immortality. Body shuffling collapses society, Chaos and war follow and eventually the world becomes a totalitarian dystopia whos only goal is to maintain immortality for the upper castes. A vast majority of humans would just be kept in a vegetative state as spare parts. The lower classes have to toil to run things. To prevent constant revolts, the hard working ones are sometimes upgraded to a higher caste. If you rebel, you are "shut off" and kept in a vegetative state or worse, your organs are harvested. Women are a very precious resources and they are treated as cattle, forced to breed as soon as they can until their death. The productive one who produce than 10 offspring are offered a caste upgrade. Babies are the primary resources for immortality after all. Society stagnates as the immortal elite eventually degenerates after centuries of hedonism. Humanity never goes to the stars and the next planetary cataclysm (metor strike, giant volcano, ice age) wipes out humanity. ]

[Question] [ The concept behind this lies in three primary points: 1. It has been theorized that one could increase the heat of Mars' atmosphere to a suitable level by guiding meteors into the atmosphere and crashing them into the surface. Assuming this is possible through pure mass, it should also be possible using cows. 2. Methane release from cows contributes a significant portion of the global warming. This would be extremely beneficial when trying to generate a stable atmosphere on Mars. 3. Fertilizer. Cows contain organic matter, which would assist future farmers when they begin their work on the freshly terraformed planet. Would it be possible to achieve a useful balance between the mass needed to heat the planet, the methane contained in the dying cows' bodies, and still benefit from having scattered cows fertilizing the planet's surface? [Answer] **1 Quintillion, or 1x 1018** This is based on a few assumptions of course, and there is a big caveat on it as well. Before you start - you need to ensure that you put a [magnetic field in place](https://www.extremetech.com/extreme/245369-nasa-proposes-building-artificial-magnetic-field-restore-mars-atmosphere). Without that, all the work you put into bombarding the surface of Mars from orbit with cows is not going to help as the atmosphere and water will be stripped away by solar winds1 and you run the risk of your cyanobacteria and other extremophile life (see later in this answer) being killed off by large CMEs and other large scale solar eruptions and events. So; once you have the magnetic field in place, we'll continue. So; the next step that you want is an ocean of some kind, and of course some organic chemicals either in the ocean or surrounding it. Fortunately cows have both. The average cow can vary in weight, but let's assume that they are around 400Kg - they contain about 60% water, so that translates to approximately 240L of water in the average cow. Your ocean on Mars doesn't need to be anywhere near the size of that on Earth; for a start, the planet is smaller. Let's say you want an ocean a little smaller than the Indian Ocean, which is approx. 284 million KM3 in volume. To make it easy on us, we'll say we want an ocean of approx. 240 million Km3. A Km3 works out to a Trillion litres of water, or 1012, meaning that a million of those is a quintillion, and given the number of litres in a cow the number of cows you need is around that figure. But, getting all that water and those organic compounds to the ground via orbital bombardment isn't as easy as it sounds. For one, the water will sublimate from the body as soon as it is exposed to the vacuum of space and any of the bacteria or other organic hangers on will die in the process as well. Also, cows are not a complete eco-system in and of themselves, so assuming that you can get the cow to drop to the surface of Mars with its water intact, you *still* need to seed the general area with plants, bacteria, animals, and the other necessities for a functioning ecology. And, the temperature and atmospheric pressure have to be conducive to their survival before you seed them. In short, if you have a functioning magnetic field already established on Mars, and you're NOT trying to actually terraform Mars via bovine orbital bombardment but merely provide a large supply of water and organic compounds, then it's *possible* that if you had 1018 cows on hand ready to drop onto Mars from a great height, AND you follow that up with some form of extremophile algae2 capable of it's own [Great Oxygenation Event](https://en.wikipedia.org/wiki/Great_Oxidation_Event), then you might have a start on the terraforming process. That said, it's still going to take thousands of years. Also, a qunitillion cows are hard to come by, even on Earth. There are currently only around 1.5 billion on Earth, so we're short by around 9 orders of magnitude. Just saying. Point of note however, please if you are going to do this, euthanise your cows prior to dropping them on Mars. It's the humane approach, AND you won't have to feed and water them on the trip from Earth. --- 1. Yes, it's true that the absence of a magnetic field isn't going to have an immediate impact, but over time the loss still be significant because you can't just dump 10^18 cows onto Mars in a single block of mass - that many cows will have about half the mass of Ceres. You have to introduce them over time, and even if you release a hundred cows a second, all over the planet, it's going to take somewhere in the order of a billion years to finish. In that time the lack of a magnetic field definitely has an effect, meaning you'd need even **more** cows to finish the job. Also, the cows that are NOT burnt to ash in that time still need working bacteria to break them down via putrefaction, and having the magnetic field in place reduces the risk of that life dying off before they can do their work. So, perhaps it's not *necessary* to have a magnetic field, but it is certainly *recommended*. I do concede though that the lack of gravity is going to have to be addressed for this plan to work as the gases released into a warming planet of that size will tend to drift away over time. 2. From comments, it is noted in some scientific papers that there are some forms of bacterial life on Earth that could survive on Mars before the cows get there, and therefore it's *possible* that the seeding of putrefactive organisms could occur before the bovine bombardment begins - certainly it could occur during according to the article. [Answer] Frame Challenge: Your first two points don't hold up. 1) Heat generated from crashing meteors into the surface is generated from the extreme speed at which the meteors travel through the air; Cows flying through the sky at that speed would not only burn up too quickly to be of any use, they would also be dead, and unable to contribute to points 2 and 3. 2) Methane is not a significant portion of global warming. The main greenhouse gas that traps heat is actually water vapor; it is the most abundant greenhouse gas in our atmosphere, both by weight, and by volume. This is why one reason why deserts are **super cold** at night, even though they're extremely hot in the daytime; there is no water vapor in the air to retain the heat during the night. --- Terraforming mars requires much more than just increasing the heat of the atmosphere with greenhouse gases. To begin with, greenhouse gases make up less than 1% of the atmosphere; and of that 1%, water vapor is 95% of it. You'd need to add enough water to the planet such that the the evaporation and condensation cycles can maintain about 1% water vapor in the air. You also need to pump in carbon dioxide, or you won't be able to grow any plants. Of course, there are other factors, but if we only consider the ones I listed, you'd have much better luck crashing comets into the planet than asteroids or cows. [Answer] You are literally putting the cart before the cows! To reach a state where cows can be mass imported on a scale needed for this project, you would already have done 90% of the terraforming effort. [Answer] Rather than terraforming Mars through just the composition of dropped cows, I propose the ambitious project to knock Mars into Earth Orbit, thereby making it easier to start the terraforming process: **The Gravitational Steak Slingshot Project** In summary, this project will require the use of **20.4 quintillion cows over the next 4,084,481,927 years**, and is fully sustainable, with the only caveat being the use of QPDs(quantum portal devices) and most of our planet food produce and space being dedicated to raising cows to jettison into space. These are the basic premise: * A cow weighs ~910kg (average of a bull and female cow). * Earth has [~1.0 billion](https://www.statista.com/statistics/263979/global-cattle-population-since-1990/) cows * We modify Earth to henceforth only focus on cows, sustaining a peak of 10 billion cows * Each cow gives birth to roughly [1 calf per year](https://s3.amazonaws.com/assets.cce.cornell.edu/attachments/16154/How_many_calves_does_a_cow_have_in_a_lifetime.pdf?146582752) * With this, we can produce roughly 5 billion cows every year, keeping roughly 5 billion to breed (this is possible because we only roughly need [1 bull per 50 cows](https://u.osu.edu/beef/1999/03/10/mating-capacity-of-bulls-bull-to-cow-ratio/) for breeding * We euthanize and jettison our 5 billion spare cows from our planet's space elevator after wrapping them in highly temperature resistant metals * The cows are precisely shot in the direction of our sun, and we use it as a gravitational slingshot, similar to what is proposed [with the Parker Solar Probe](https://www.space.com/41447-parker-solar-probe-fastest-spacecraft-ever.html) * The cows will reach a peak speed of 692,000 km/h and sling around the sun, becoming wellx109001 done steaks inside the foil * through a carefully calculated trajectory, it will shoot through a quantum-portal set up near the Sun, with the other end pointing to the right of the trailing side of Mars, right after reaching peak velocity in the gravitational slingshot * the wellx109001 done steak will impact the surface of Mars from the side, propelling Mars towards Earth orbit and vaporizing into its base components * The results from roughly 360 trillion cows will change the orbit of Mars to coincide with that of Earth's in 72,040 years Calculations: ``` Cows: 5,000,000,000 cows/year 910 kg/cow = 4.55 x 10^12 kg/year Speed: 692,000 km/h 6.062 x 10^9 km/year Mars Weight: 6.39 × 10^23 kg Distance from Mars Orbit to Earth Orbit: 54,600,000 km ``` Simplifying impact calculation to find resulting velocity, assuming the cow collision is perfectly elastic, with no loss of energy involved, for 5,000,000,000 cows a year (and luckily with no air friction, assuming our portal is placed flush against the surface of Mars): Mcows\*Vcows = MMars\*VMars VMars = Mcows\*Vcows / MMars Mcows = 4.55 x 10^12 kg Vcows = 6.062 x 10^9 km/year MMars = 6.39 × 10^23 kg ``` V_mars = 4.55 x 10^12 kg * 6.062 x 10^9 km/year / 6.39 × 10^23 kg V_mars = 0.04316 km/year ``` We know that these numbers are for our yearly cow rate, so we know that Vcow\_speed/year is equal to this V\_mars / 1 year Assuming we shoot out 5,000,000,000 cows a year, and add this speed to Mars each year, the distance traveled by Mars can be plotted out by a linear line, where the slope is Vcow\_speed/year. The area of this function is the distance traveled, which we want to equal half of the distance from Mars to Earth, 28 million km. To find the years needed to achieve this distance (with years as y), the formula for this function is 28 million km = (Vcow\_speed/year)\*y2/2. ``` 28,000,000km = (0.04316 km/year^2)*y^2 / 2 y^2 = 28,000,000km * 2 / 0.04316 km/year y= sqrt(1297497683 year^2) y= 36020 year ``` This is only for half of the distance traveled, once this is done, we must employ more cows from the opposing end, for the next 36,020 years to bring Mars to a stop. Thus, to send Mars into a similar orbit around Earth, we will need 72,040 years and (72,040 \* 5,000,000,000) ~= 360 trillion cows. *Edit*: It seems that we need to revise our answer. To change the orbit of a planet does not depend on its distance from the sun, but its orbital speed. As referenced from [here](https://space.stackexchange.com/questions/3854/how-would-we-move-venus-or-mars-into-earths-orbital-zone), we will need to change the orbital velocity to perform a Hohmann transfer of Mars: > > The most efficient way to move from one orbit to another is via a Hohmann transfer. We'll apply a delta-V to Mars to slow it down and put the planet into an elliptical transfer orbit that just intersects Earth's orbit, then another delta-V once Mars reaches perihelion. Assuming Mars is orbiting circularly at 1.524 AU, a retrograde delta-V of 2.65 km/s will put Mars on that transfer ellipse. Half an orbit later, another retrograde delta-V, this time 2.94 km/s, will put Mars in a 1 AU circular orbit. No problem! All we have to do is change Mar's velocity by 2.65 km/s and then later by 2.94 km/s, or a total delta-V of 5.59 km/s, and voila! we have Mars orbiting at 1 AU. > > > To shift the orbital speed of Mars by 5.59km/s (equivalent to 176,286,240 km/year) we will need to divide this by Vcow\_speed/year instead, to get the number of years needed. This comes out to 4,084,481,927 years and 20.4 quintillion steaks, although the gravitational pull of Mars and Earth should greatly reduce this number. This comes off a lot more than the previous number due to us needing to change the orbital velocity of the entire planet, rather than simply shifting its trajectory over time. Please don't take the calculations too seriously, it's obvious we don't have any QPDs, space elevators, etc. With 360 trillion collisions equaling to roughly 2518880000000 nuclear bombs, we would be lucky if any of Mars remained by the time it arrived. We also don't consider the inelastic nature of a 910 kg steak hitting the surface of Mars, nor the needed distance from the sun for Mars to reach similar temperatures as Earth, considering a difference in atmospheric gases, surface area, etc. We also don't consider the potential consequences of Mars being in a similar orbital distance from the Sun as Earth. [Answer] Assuming cows would survive (which is a false assumption), there are a number of possible answers: 2 would be enough potentially (one male, one female), if they had enough food, water and air, because they would soon become 4, 8, 16, 32, etc. until their population expanded to fill the whole planet. There is a risk in that one might die before they bred offspring of the right sex, so at least 2 of each sex would be a sensible precaution. With such a small breeding stock, as well as risk of death of individual animals, there is the risk of inbreeding causing unwanted genetic defects, leading to sickness and infertility. To counteract this, you would ideally want to start from a genetically diverse breeding stock of at least 64 individuals (approximately). This sort of population size is the absolute minimum to capture the wide diversity of all cows, if you ensure that no two cows are closely related. You would probably also want to at least double this number to accommodate the risk of individuals dying without reproducing. ]

[Question] [ I'd like to have a realistic idea of how, and how accurately, ordinary people in a rural low-tech (medieval-equivalent) setting should expect to hear news from outside their own communities. If you don't personally travel (which, I believe, most did not in our own medieval period), by what means does the news come to you? How quickly does the regional rumor mill operate, and how accurate does it tend to be? How (or does) it vary by the type of news, e.g. news from the distant royal court versus news about widespread illness three towns away? Please assume a social structure and population distribution comparable to that of historical Earth. If you can base an answer on our own history, great. Otherwise, please explain your reasoning. [Answer] It depends on the type of the information. * The maximum speed of official documents was the speed an envoy could travel at on horseback. If the news were deemed important to the general population (new laws, a new king, etc.) they would be announced by town criers or priests. * Carrier pigeons were used in the Crusades, but it's not something the common villagers would have access to. * General knowledge (how other countries look like, what other cultures exist, what interesting events like a battle, a plague, an earthquake etc. happened) traveled much slower, as it was spread by traveling merchants, armies, or peasants returning home to their village from a military service. * While you can send full textual information via [semaphore signals](http://en.wikipedia.org/wiki/Semaphore_line), it wasn't widespread until the late 18th century. It was pretty fast, the message delay was about 6 minutes for the Paris-Strasbourg distance (approx. 360 km air distance), but it took one minute for each letter. I included this because even though it wasn't used in the middle ages, the technology for it existed, so a fictional world with the same level of technology can make use of it. Simpler versions of this were probably used even in antiquity, to raise an alarm, etc. * Similar to the semaphore line, there was a system of communication which was used in medieval Europe: lone trees on hilltops set on fire to warn of an enemy invasion. This might interest you as you asked for news between common people. The limitation of this is that a communication about the meaning of the fire must be agreed with beforehand, so no specific messages can be sent. Just something like "We already know there are bandits roaming the countryside, so if the shepherds in the mountains see them, they can make a big fire so people in the village see it and can hide their valuables in the forest." I faintly remember it being used in at least one peasant revolt, to synchronize all the revolts across the country. If they don't revolt at the same time, the nobles can easily defeat them one at a time. The method is simple: if you see a large fire on the top of a distant hill, you go and light a fire on the top of the nearest hill. [Answer] I'm pretty sure, that no matter which form of "news transmission" you pick, you'll always be tied to speed of typical horseback riding, if we're speaking about medieval Europe or a virtual, fantasy world with the same level and stage of development. Whether it will be a diplomatic letters exchange, gossips traveling with traders or news brought by wandering mercenaries, it will always be able to travel no faster than riding a horse. Much often, slower. Simply, because people hadn't found a faster way of transportation at that times. I think, we may assume, that a typical messenger, soldier, mercenary or trader can ride a horse for approximately ten consecutive hours (twelve hours or more or from dawn till dusk, but including few hours for horse and rider rest). This is the first factor (time), you can use in estimation for an answer to your question. There are many sources (like [this](https://answers.yahoo.com/question/index?qid=20100120005540AAw7rUw), [this](http://boards.straightdope.com/sdmb/showthread.php?t=426426) or [this](http://www.cartographersguild.com/reference-material/19730-how-far-horse-travels-one-day.html)), that are trying to estimate how far can a typical horse travel. This, of course, highly depends on type of horse ride, whether you can change horses during one-day travel, what kind of horse do you have (how old it is) and what kind of terrain you're traveling etc., etc. A loose estimates from above mentioned answers seems to suggest, that you can expect from 20-30 miles per day for a leisure type of traveling or fast-moving travel in hilly terrain to 40-50+ miles per day in extreme fast travels, with changing horses, pushing them to limits and making very little or no rests. Basing on these calculations, you may widely assume, that if city A is in distance of 100 miles from city B, news will need 3-5 days to reach. These are very wide assumptions, that does not include other factors (how urgent message is -- from critical to gossip, if there will be immediate message spread or just by accident news spread etc. etc.). So, I think, you can use my answer just as a base for further research. ## Ancient Persians **Edit** (Nov 3 '14): As per *Bobson*'s comment about [Persian Royal Road](https://en.wikipedia.org/wiki/Royal_Road): "*Mounted couriers could travel 1677 miles (2699 km) in seven days*". This gives us an hardly to belive (yet verified) value of 385 kilometers (239 miles) per one day of message travel in ancient Persia, 5 centuries before Christ and around 10-15 centuries before *so called* Middle Ages (depending on what point of Middle Ages history one thinks). ## Ancient Egyptians **Edit** (Sep 27 '15): Basing on information provided in "[Pharaoh](https://en.wikipedia.org/wiki/Pharaoh_(novel))" book, by the Polish writer Bolesław Prus, message travelling from Wadi El Natrun ([Google Maps](https://www.google.com/maps/place/Wadi+El+Natrun,+El+Beheira+Governorate,+Egypt/@30.4420051,30.225769,18z/data=!3m1!4b1!4m2!3m1!1s0x1458b46af3bf9f5d:0x36a152b341d3a1d6?hl=en), [Wikipedia](https://en.wikipedia.org/wiki/Wadi_El_Natrun)) to ancient Thebes ([Google Maps](https://www.google.com/maps/place/25%C2%B043'14.0%22N+32%C2%B036'37.0%22E/@25.720556,32.610278,15z/data=!4m2!3m1!1s0x0:0x0?hl=en), [Wikipedia](https://en.wikipedia.org/wiki/Thebes,_Egypt)), that is on distance of [755 km / 470 miles](https://www.google.com/maps/dir/Wadi+El+Natrun,+El+Beheira+Governorate,+Egypt/'25.720556,32.610278'/@28.576699,31.2466155,7z/data=!4m13!4m12!1m5!1m1!1s0x1458b46af3bf9f5d:0x36a152b341d3a1d6!2m2!1d30.2249474!2d30.4416481!1m5!1m1!1s0x0:0x0!2m2!1d32.610278!2d25.720556?hl=en), **there and back** (so 1510 km / 940 miles in total), would take 24 hours. Excluding just one hour for writing message and answer and exchanging messengers, that gives a hard to believe (in terms of ancient Egypt, around 1000 B.C.) speed of 65 km/h or 40 mph. There is absolutely no information on what kind of animal or other meaning of transportation ancient Egypt's messengers were using (I assume, they were using horses after all). The same source few pages laters claims, that distance from mentioned Wadi El Natrun ([Google Maps](https://www.google.com/maps/place/Wadi+El+Natrun,+El+Beheira+Governorate,+Egypt/@30.4420051,30.225769,18z/data=!3m1!4b1!4m2!3m1!1s0x1458b46af3bf9f5d:0x36a152b341d3a1d6?hl=en), [Wikipedia](https://en.wikipedia.org/wiki/Wadi_El_Natrun)) to ancient Memphis ([Google Maps](https://www.google.pl/maps/place/29%C2%B050'40.8%22N+31%C2%B015'03.3%22E/@29.844667,31.250917,16z/data=!4m2!3m1!1s0x0:0x0), [Wikipedia](https://en.wikipedia.org/wiki/Memphis,_Egypt)), that is [151 km or 94 miles](https://www.google.com/maps/dir/30.441575,30.2252218/29%C2%B050'40.8%22N+31%C2%B015'03.3%22E/@30.1818228,30.4297776,10z/data=!3m1!4b1!4m6!4m5!1m0!1m3!2m2!1d31.2509167!2d29.8446667?hl=en) can be travelled on horse, by [working trot](https://en.wikipedia.org/wiki/Trot#Types) within five hours. Original question is about medieval Europe, about 1500-2000 years later than mentioned example. But since development of ancient Egypt was more or less equal to development of medieval Europe, I think we can skip that years difference. ## And... **Edit** (Dec 15 '15): ...there also are [magical horses](https://scifi.stackexchange.com/a/39528/7885), since we're discussing the matter on Worldbuilding.se. [Answer] I've found [the ORBIS site](http://orbis.stanford.edu/) to be useful in estimating travel times. While this site focuses on the Roman era, The travel times are probably fairly equivalent in the medieval period as well. For example, the fastest travel form Roma (present day Rome) to Londinium (present day London) was 9.2 days covering 2018 km. [Answer] I did not read the whole comment section of Trejder´s answer, but i want to point on the ## **[GREAT CHINESE WALL](http://en.wikipedia.org/wiki/Great_Wall_of_China)** As one of the fastest ways to communicate when not the fastest way in the times before the telegraph. If a Mongol or some other rival Tribe was in sight, the nearer Tower lights it Signal fire. all Tower that sees that fire en light their own until the fire reaches a castle or fortification. There the troops are stationed and will eminently go where the Fire line started. In Fantasy - the beacon of Rohan in the Lord of the Rings are the same. **So its not quite Europe but this would totally be possible in the woods of Germania or on the Limes of the Romes.** [Answer] As I’ve heared in the past the millers in windmills have had implemented some basic semaphore system. As there were many wind driven mills in former days and the millers could see some mills around from the tops of their own mill, they used it in times when no wind was blowing to exchange some news. There were flag signals in how to position the sails, such as to say “the king died” or “pest broke out”. There should have been a communication network all over northern europe. Maybe this is one reason that millers were outlaws and seen as to be in contact with the devil… Well, I only heard this story once and have no proof for it by now—though I would be interested in some—neither I know if this already existed in the middleages or came up later, nor if it is true at all, nor how many flag signals ever existed. The main limiting aspect of this communication channel is that there must be time without wind (or without work to do) for the millers to misuse their mill for communications. However, all along the time of daylight, there are often time slots where there is not enaugh wind for a windmill to operate. One more aspect, millers are part of the rural world, not the governing, so they may be better to communicate without political censorship. People came to a mill probably every three (or at least six) weeks, since floor isn’t that well storable. Even if it is only a tale, it may inspire anyone for fictional literature. ]

[Question] [ This really gets to me when I watch modern-day Christmas movies. These movies usually present the notion that Santa exists and adults don't believe in him. From what I've seen, it's either because of one incident where someone didn't get what they wanted or they simply grew out of it. This creates a paradox: people don't believe in Santa and yet he unquestionably exists. How do you create a world where * Some (or most) adults do not believe in Santa, but * Santa exists and fulfills all of his cultural duties (in the US: giving gifts to good children and giving coal to bad ones, eating milk and cookies, riding on a sleigh, going down a chimney, etc.) Points to consider: * People will notice a sleigh on their roof and extra presents under the tree or coal in their stocking * Santa could be tracked in the sky, perhaps even an app could be developed to pinpoint his location for irrefutable proof * He lives at the North Pole. He might even pay taxes [Answer] Santa is real and does exactly what he is supposed to do. He delivers gifts to good children and coal to bad; and he does it all in one night. This sounds like an impossible task until you realize how mediocre most of us are. None of us is really good or evil, and neither are our kids. It is in the nature of every child to be selfish; it's a survival trait and any resistance of juvenile selfishness has been bred out of us centuries ago. "Because I want it!" is every child's battle cry and uttering it, even once, gets that child scratched off the Nice List. But children are also inherently harmless. Very few of them pull wings off of flies or torture puppies. Santa's standards are pretty high, so making it onto the Naughty List is also beyond the abilities of most rug rats. So the reason that you never see a sleigh parked on a neighbors roof, nor find unexpected items under your tree, is that neither your children nor those of your neighbors made the cut to be on either of Santa's lists. ...and that's a very good thing! For Saints grow up to be martyrs and serial killers go the chair; Happiness is available only in the space between both of those extremes. Santa actually has a pretty good gig. Most years, he doesn't even have to saddle up the reindeers. We should all be very happy that in place of roof-bound hoof beats each Christmas, we are blessed with a most silent night. [Answer] **Santa could have a perception filter.** Adults think they buy gifts, and see the nightmare *after* Christmas (the credit card bills) as appropriate. They don't see the sleigh on top of the roof, and ignore any reindeer poop on their cars as just evidence of a very ill pigeon. As kids get older, the perception filter starts to kick in retroactively. After all, if you thought you saw Santa as a child, which would you think more likely nowadays as the reason -- that Santa was real, or that those were the confused perceptions of a child? We see this in other circumstances, such as when, after months of infants screaming everyone awake at 2 AM, parents think about having a second child and decide they can't think of any reason -- any reason at all -- not to. If humans weren't vulnerable to this kind of psychic blindness, I think our species would have died out ages ago. **Edit**: Per Saidoro and Oldcat's suggestion, the money actually goes to pay for more Purina Reindeer Chow & some money for the elves. It's all channeled through shell companies -- Santa has had centuries of experience with finance. When the parent sees the line in the credit card bill from SantCo (a division of Borealis Industries, Inc.) they mentally translate it into Toys 'R Us or, sometimes, the coal company, as appropriate. [Answer] Another possibility is to turn Santa into more of a wraith like creature who can posses parents - he might still travel around with reindeer and sleigh, but once he is down the chimney he possesses the parents. During the lead up to Christmas day Santa's wraith like elves do the job of coordinating what the parents buy. The parents are completely unaware of the possession, or just think it is "holiday cheer". If you need to explain people not seeing the sleigh, either deploy a handy-dandy handwavium shield, have him traveling fast enough we cannot see him, or have the sleigh projecting some kind of mind warping field that blanks the memory. [Answer] Perhaps Santa is the biggest business tycoon in all of history, and the toys that parents are buying *are* created by the elves in Santa's workshop. Santa has a factory line going 365 days a year, and distributes the toys made to shops for parents to buy, and uses the profits to buy more materials for next year. This would get round the problem of delivering all the presents in one night, you simply use the parents as the middle people. Even the naughty/nice list duties have been delegated to the individual parents, because Santa doesn't have the time. But nearly all parents would put their own children on the nice list and buy them the presents. [Answer] Let me be the one to clear up any controversy regarding Santa, as I am the man himself. Yes, I know its hard to believe, but its true. I come to your house ~~every night~~ every Christmas Eve, drop down your chimney (or through a window if you don't have a chimney), and leave you presents. I do live on the north pole, but the weather [isn't that bad](https://www.google.com/search?q=north+pole+weather&oq=north+pole+weather&aqs=chrome.0.0l6.1563j0j4&sourceid=chrome&es_sm=91&ie=UTF-8). I *do* have a toy factory up here, and my minimum wage elves do a great job making toys for little boys and girls. The naughty list *does* exist, and [its not hard](https://xkcd.com/838/) to earn yourself a spot. Although I've never given out coal to these naughty children, [I have been known to give PHP textbooks](http://chat.meta.stackexchange.com/transcript/89?m=2368144#2368144) to the worst of the worst. My reindeer are doing well. [Answer] Mayans sacrificed people to enable their gods to keep the universe existing. Parents buying presents is the actual sacrifice needed for Santa to be able to do his job. He exists to confer transcendence to what otherwise would purely be a private ceremony. [Answer] Why can't Santa be a god? Not a god as we normally understand it, but a [*Discworld*](http://en.wikipedia.org/wiki/Discworld) sort of god. By that, I mean an entity born out of belief, and posessing power directly proportional to the amount and strength of belief in him. Considering the number of children worldwide who believe in one or other form of Santa (these exist in many, many cultures), Santa could be a very, *very* powerful god. Hopping into millions chimneys at once to leave innumerable presents; fiddling with parents' minds so that they think that *they* bought the extra presents (and with the stores' records to confirm this); and of course, most importantly, making himself be seen only to those who make it all possible by believing in him... These feats should be well within Santa's power. Of course, he would be a complicated god, one with many faces, changing at will from Santa Claus to [Père Noël](http://en.wikipedia.org/wiki/P%C3%A8re_No%C3%ABl), morphing his army of elves into one [Belsnickel](http://en.wikipedia.org/wiki/Belsnickel) or [Snegurochka](http://en.wikipedia.org/wiki/Snegurochka), etc. [Answer] ## For the same reason people don't believe that aliens exist We can draw an analogy between Santa and aliens. * Although many people claim to have seen aliens, these people are treated as cranks or lunatics. Claiming to have seen an alien virtually guarantees you will be treated as mad. * Although there are apparently pictures of flying saucers, these pictures are always a bit blurry. They are most likely hoaxes, or if not, they must have some natural explanation, ball lightening or experimental aircraft. * Although aliens apparently leave crop circles, these could easily have been placed by students under cover of darkness. Likewise that extra present under the tree was probably dropped off by Auntie Flora last week, wasn't it? * Moreover, admitting a belief in Santa would have serious social consequences. Anyone in possession of evidence supporting the Santa will most likely want to keep said evidence private for fear of scorn and derision. [Answer] Santa could be active well before Christmas. He charms parents of good kids to buy more generous gifts, and he confuses parents of bad kids to bring coal instead of gift (thinking it is a good fun idea). He may be invisible spirit, or he may really be a businessman, toy producer, who secretly puts charms on his toys. Adults see his elves as Mexican workers, and his deer are a nose figure on his Jaguar car. However, on Christmas night, Santa inspects at least some of the children to ensure, that they got the treatment they deserved. And if something went bad, like the parent lost a present, Santa works magic. Adults notice that magic, but it happens rather rare, they can not persuade each other that something miraculous happened. [Answer] Once upon a time Santa did all the work himself. Toymaking, hiring coalworker and the logistics. After some years he realized that this is a pretty dumb way to do. He outsourced the work to the parents. **He became a master in manipulation** Santas plan was ingenious and evil at the same time. His first action was buying majority shares of toymaking companies and placing, right before christmas, ads all over the world. The ingenious part was now to remove himself from the next christmas, NOT delivering the toys. The crave for toys generated by the ads and the missing Santa lead the parents to the toy-stores, taking the matters into their own hands. The legends still exist of Santa, the tradition carries on. Santa is at the beach, rich beyond imagination, drinking Mojitos while amusing himself with babes. [Answer] The particular adults who don't believe in him were naughty kids themselves and so never got presents. They now buy presents for their kids (since they don't believe) so Santa doesn't need to. Two lots of toys would just be spoiling them... [Answer] The people in these movies actually live in a deeply totalitarian regime where the population is kept under control by pervasive surveillance, secret justice, and arbitrary punishment. Santa is an important part of this regime. However, the society is materially successful. This seems to match Santa's capabilities and situation. The adult population is deeply traumatised by experiences during brutal national service as teenagers, or similar personal assault, (not necessarily systematically, but pervasively and by the state or its agents or those in privileged positions) such that any casual acknowledgement of its existence has become taboo. Along with this sanctions preventing discussion of the secret service for those above the age of majority. As a result of these incidents the secret police, Santa among them, can go about their business quite publicly. Children can acknowledge his existence quite publicly, but adults are forced to pretend that they don't believe in him or pretend to others or even individually repress any sightings of him. Any attempt for an adult to acknowledge Santa or his effects would risk their personal security, and that of their families under "terror laws" in secret courts, would publicly ostracise them, leave them liable to attack by their contemporaries. [Answer] When Santa comes down the chimney, he steals all the toys left by the parents (for next Christmas) and leaves his own (stolen from parents last Christmas). The cookies are just delivering fees. [Answer] Santa is actually a minor god, and like all gods, his power and presence are both fuelled by human belief, and (crucially) uninhibited by the constraints of time. Parents tell their children that Santa is coming, and they *really do* buy them gifts. Then, having done this, they claim that these gifts are from Santa (this explains both why they remember doing it, and why children are able, on occasion, to discover them doing it, and to stop believing in Santa as a result). When the children find the presents, their weak belief in Santa is strengthened to the point where Santa can physically materialise in their home. When this happens, the local timeline is altered. The parents now never bought the presents, which *really were* delivered by Santa, but since humans *are* constrained by time, the parents' memories of the alternative timeline remain intact. As far as they're concerned, Santa doesn't exist, and *they* are responsible for the presents. You might also be interested to note that, as of 1939 or so, Rudolph has always existed, and has (at least as far as Santa can recall) always had a very shiny nose. [Answer] Santa Claus is a spirit, he counsel the parents to buy (or not) presents to their children. Its a kind of unconscious spiritual channelling. People do a lot of things daily that they don’t know why. So, Santa Claus, who is actually Saint Nicolaus, is the patron of a legion of angels who work with children and help parents raise them. This legion of angels visit parents in their dreams and counsel them on what to do on the next day - they can predict the next day. Once woke up, the parents do what they decided while asleep. There are other legions of angels who work on other areas of life too. Solved. ]

[Question] [ In my world, humanity reaches their new home among the stars by way of a portal that pops into the solar system one day. This portal instantaneously transports those who enter to a place that is located a jaw-dropping 6 gigalightyears (six **billion** lightyears) from Earth. But the astronauts traveling there don't know that. **Would it even be possible for them to determine how far they had been transported?** And in what direction? I would imagine that they'd look for known galaxies, or perhaps look at the cosmic microwave background for clues. But those things might appear radically different, considering the astronauts have been transported over a billion years into the past (or is it the future? Wormholes confuse me). [Answer] ### Edit: The OP updated in a comment that communication is possible through the portal. My answer assumed that you had to figure out where you were from the other side, using only the information you brought with you. If you can do observations from both sides of the portal, then there is a way to find out where the other side is, so long as the event horizon of the other side overlaps with Earth. At 6 Gly, the event horizons should overlap. EricTowers' answer provides a way of doing so. # Hard No 6 giga-light years is a very long distance. The fundamental problem with identifying anything if you were mystically transported that distance away, is that the scale of light years also corresponds to a scale of years. That is, *traveling such a great distance also causes you to effectively travel through time*. ## Travel through space is travel through time For an example of what I am saying, if you were 6 billion light years away and could somehow see the Earth across that distance, you would be seeing the Earth 6 billion years ago. That is, you would see the Earth before the sun even formed, so you wouldn't really see Earth at all, just a cloud of interstellar gas. In fact, you would effectively have traveled to a 'time' when Earth doesn't exist for you; Earth's existence in space and time is outside your event horizon after going through this portal. ## The universe is different at a different 'time' Applying this to the cosmos at large, you will fundamentally not be looking at the same universe that we can observe from Earth. At only a few points in the universe would you be able to observe the things that you can see from Earth at the time you left Earth. Assuming simple Euclidean geometry (note: not a good assumption in this case! but easy to understand), the only things that you can see that you could also have seen from Earth are those that are exactly the same distance from Earth and your new location; this forms a plane. Anything not within a few tens of millions of light years of this plane will not look the same at all; stars would be born or die, galaxies would move relative to each other, collide or fall into black holes or whatever. Everything else in the universe would be novel. You would either be looking at things hundreds of millions to billions of years in the past, or hundreds of million to billions of years in the future, from the perspective of Earth. And thus, you would be looking at things that have never been seen from Earth (by humans at least). Even the largest scale objects in the galaxy would be hopelessly confused over these kinds of time scales. Furthermore, what exactly are the chances that anything large enough to be seen across the universe is aligned with this plane? I can't do that sort of calculation, but the universe is vast, and even a plane 100 million lights years across would only contain a fraction of the objects we have cataloged in the universe. And our catalog is itself a nearly infinitesimal fraction of the objects actually out there in the universe. ## Conclusion I conclude that even with the best star maps produced, and the most powerful supercomputers available, there simply isn't enough similarity between the sky you are looking at and the sky you know from Earth to make any sort of comparisons. That will itself tell you that you are very, very far away, I suppose. [Answer] I waited a whole minute for OP to answer my clarifying question about continuous signalling through the portal. :-) I assume the answer is "yes" now. ## Hard yes. Set up a [very-long-baseline interferometer](https://en.wikipedia.org/wiki/Very-long-baseline_interferometry) (VLBI) with one aperture on each end of the portal. (Congratulations. You have now made the largest telescope accessible by humanity.) Real VLBIs don't actually need continuous real-time sampling from all participating telescopes. Data can be recorded (at very high speed) and the resulting interferometry done by combining datasets. So my question about continuous signalling through the portal suggests a tougher requirement than is actually needed. For each sufficiently large $z$ (redshift) as measured from one planet, you will find one arc on the celestial sphere of each planet where the interferometric data has persistently large cross-correlation. This arc corresponds to the directions along which the two planet's past light cones intersect (at the right $z$ as measured from the one planet). That is, along that arc, both telescopes are watching light emitted by the same process the same time-of-flight away from(see below) the two telescopes. If you move off that arc to one side, the time-of-flight of apparent coincident events to both telescopes increases or the time-of-flight to both telescopes decreases, so if there are coincident events, they do not have the selected $z$.(see below) These arcs can be plotted to make a "bullseye" in the sky. This pattern is centered on the direction towards the latest time (smallest $z$) event that has (or, *had*) both planets in its future light cone. One could point at the center of the pattern and claim that the other end of the portal is "that way". If the other end is space-like separated from this end, then that claim is hampered by a coherent choice of coordinate system. (It would be more accurate to say that the light from events at a certain $z$ shift in "that" direction travelled in opposite directions to arrive at the telescopes at each end of the transport system. However, during the astoundingly long time it has taken the light to make the journey to each planet, both planets, as well as the light producing object(s) have moved substantially, so where the other end of the portal appears to be (at the bullseye), where the other end of the portal is "now" (whatever that means in the absence of a universal coordinate system), and where you would have to shine a light so that its photons would eventually (maybe) strike the planet of the other portal are wildly different and not practically useful.) The pattern of the arcs is sufficient to tell you the distance in space and time from each to the latest time (smallest $z$) event that has both planets in its future light cone. As an easy to work out example: If the temporal shift is nearly zero and the spatial shift is nearly zero the patterns are concentric circles. Decreasing $z$ rings shrink down to the direction pointing at the other end of the portal. The planet in the future has slightly larger $z$ shifts than the planet in the past to coincident events. The $z$ (redshift) of the light from apparently coincident processes along the arcs of fixed $z$ will tell you how far back in time along the cone you have to go to reach the intersection with the other light cone. This is sufficient information to recover the time and spatial shifts. If the separation in space or time is large, there is a reasonable chance that other galaxies (or other large structures) could appear to lie on the arcs. As a consequence, there could be gravitational lensing making the "an arc" a simplification of the reality of "a narrow-ish band with several complicating micro-features." Nevertheless, after a few months of observations, one should be able to establish rather sharply where/when is the other end of the portal. --- Edit 20171208 13:50 UTC The text > > That is, along that arc, both telescopes are watching light emitted by the same process the same time-of-flight away from(see below) the two telescopes. If you move off that arc to one side, the time-of-flight of apparent coincident events to both telescopes increases or the time-of-flight to both telescopes decreases, so if there are coincident events, they do not have the selected $z$.(see below) > > > has the cart on the wrong side of the horse. The correct phrasing is > > That is, along that arc, both telescopes are watching light emitted by the same process with approximately the same arrival time (say, within a month) to the two telescopes. If you move the event with a space-like separation the two arrival times change oppositely -- the event is observed earlier at one end and later at the other end. If you move the event with a time-like separation, the two arrival times change together, both becoming later or earlier together. > > > Note that this is an approximate coincidence detection measurement, not an interferometric measurement. The most useful fact about an event is its [absolute magnitude](https://en.wikipedia.org/wiki/Absolute_magnitude), its spectrum, and its $z$. Coincident events have approximately matching absolute magnitude and spectrum. Further: There are several types of events we could watch for, many of which are susceptible to whole sky surveillance. It is helpful to know that 6 Gigalight years, 6Gly corresponds to $z ~ 1.5$. (This and all Gly measurements below are in [comoving coordinates](https://en.wikipedia.org/wiki/Metric_expansion_of_space#Overview_of_metrics_and_comoving_coordinates).) * [GRBs](https://en.wikipedia.org/wiki/Gamma-ray_burst) : BATSE DISCLA data's BD2 sample has about 4500 events with about 1400 quality events ($0.1 < z < 6.5$, or 0.6 to 27 Gly) from a 2 year full sky survey using 1980s technology. See [Schmidt, 1999](https://arxiv.org/abs/astro-ph/9908190). This gives 50-ish candidate events per month for coincidence detection. * [Supernovae](https://en.wikipedia.org/wiki/Supernova) : IAU Circulars have reported 6264 supernovae this year. This data is collected and summarized [here](http://www.rochesterastronomy.org/snimages/). The range in $z$ for those with measured $z$ (only about 20% of the events) is 0.000133 to 0.915 (0.008 to 10 Gly). Observing supernovae to $z \approx 1.75$ (to 16 Gly) [is currently feasible](http://arxiv.org/abs/astro-ph/0701584). This gives 500-ish candidate events per month for coincidence detection. * Type Ia Supernovae : The [Sloan Digital Sky Survey](https://en.wikipedia.org/wiki/Sloan_Digital_Sky_Survey) (SDSS) in a 300 square degree area (about 2% of the sky) found 130 SN Ia events in 2005 and 197 in 2006 giving a dozen-ish [standard candle](https://en.wikipedia.org/wiki/Standard_candle) (i.e., very well characterized absolute magnitude) candidates per month, or 100-200 such events per month in the whole sky. * [Quasars](https://en.wikipedia.org/wiki/Quasar#History_of_observation) : The 2000-2008 [SDSS-I and -II surveys](http://www.sdss.org/surveys/) observed 100,000 quasars. Subsequent surveys (to the present) have cataloged another 100,000. These have $z$ from 0.056 to 7.085 (0.3 to 28 Gly). This suggests an observation rate of 1000-ish objects per month. Quasars are variables with time scales of hours to months. These would be the first candidates on this list where correlating variations in brightness would be the measurement, rather than just recording coordinate and spectral data for the short event itself. * Quasars (again) : The [International Celestial Reference System](https://en.wikipedia.org/wiki/International_Celestial_Reference_System) is mostly based on quasars, with measured $z$ up to 4.301 (24 Gly). Many are $1 < z < 3$ (11 to 21 Gly). Consequently, several of these will be in the intersection of the past light cones of two objects with spatial separation 6 Gly and not more than a few Gy time separation. * et c. : Turn-on and turn-off events for non-quasar AGNs, and non-EM detections, including neutrino and gravity wave astronomy. [LIGO](https://en.wikipedia.org/wiki/LIGO) and [Virgo](https://en.wikipedia.org/wiki/Virgo_interferometer) have so far reported 4-ish events per year (at distances of [0.13](https://en.wikipedia.org/wiki/AT_2017gfo) to [1.5](https://en.wikipedia.org/wiki/First_observation_of_gravitational_waves) Gly). Conveniently, the universe is largely transparent to gravity and neutrinos, so interferometry is automatically feasible for these. So these are the events to measure. What do you do with the measurements? Pick your favourite cosmological spacetime model, for instance [FLRW](https://en.wikipedia.org/wiki/Friedmann%E2%80%93Lema%C3%AEtre%E2%80%93Robertson%E2%80%93Walker_metric). Call the two portal endpoints "A" and "B". The spectra of events observed at A are compared with spectra for events observed at B. [Hough transform](https://en.wikipedia.org/wiki/Hough_transform) matching pairs onto the parameter space of lightcones in your spacetime model. Mismatched events will be scattered over this parameter space. Matched events will lie on/near the surface of intersection of the past lightcones of the ends of the portal. So far, this has not describe an interferometric technique. However, interferometry for events not "on the line" between the two planets is feasible -- such off-axis events are from more-or-less one side of the event, so coherence increases as the event moves off the axis. Thus, fine-tuning the candidate spectral matches by cross-correlation of short time scale intensity fluctuations, reduces the false matches used to populate the parameter space. (That is, we put less noise in the Hough estimate of the surface of apparent coincidence.) If the time shift is a bit more -3 Gy or a bit less than 12Gy, then the two past lightcones intersect on a surface that includes the highest density of events listed above, with $z < 1$, from whichever endpoint is earlier. For time shifts outside of this range, the past light cones do not intersect (except at the Big Bang). For time shifts between these, least $z$ for a coincidence decreases to 0.25 for zero time shift. These numbers help us characterize how likely a coincidence event is to be observed during a particular observing window. As long as the past lightcones intersect, we may observe a coincident event. To simplify calculation, let's pretend events are uniformly distributed on each lightcone. Lightcones extend about 13 Gy into the past. Every month the light cone sweeps through about 1 part in $10^{11}$ of past spacetime of the planet. We distribute 10000 events in that volume, so the probability that none of these events is in the intersection of the lightcones is $1 - (1 - 10^{-11})^{10000} = 99.999990\dots \%$. After a year, $99.99988\dots\%$ chance of no coincidence. This seems hopeless, doesn't it? It's not as bad as that, though, because observed events are *not* uniformly distributed in $z$. Instead, we are roughly 10000-times more likely to observe an event with $z < 2$ that an event with $z > 6$. (Look at the sources above, $z > 6$ is a once-per-year rarity (60 quasars over 60 years). $z < 2$ is a 10s-100s per day event.) Also, with a separation of only 6 Gly, the $z$ for events "between" the planets are less than 0.75. Consequently, we're scattering 10000-times as many events in half as much light cone. With this adjustment, the odds of no coincidence per month are 90%. The odds of no coincidence in the first year are 28%. So, every few months, we expect to get a new coincident event to update our Hough transform. This is roughly equivalent to our current state of the art in gravitational astronomy - a reportable event every few months. So my "from the hip" estimate of how long to get space and time shifts was off by an order of magnitude. It will take a few years to get a sharp result. I'm not unhappy with the quality of that estimate. [Answer] This would be hard. You need to look for objects that are: 1. Detectable from 6 billion ly. That excludes, for example, neutron stars, as we cannot detect old pulsar even outside of our galaxy. 2. Stable enough to remain recognizable if we would look at it 6 billion years ago. That excludes quasars, that are basically extremely bright accretion disks around giant black holes. Accretion disk does not "hold" any memory - it can easily become much brighter or dimmer, depending on amount of incoming matter, it does not hold matter for long - it gets either consumed by black hole or thrown out. Also that excludes galactic clusters - in 6 billion years galaxy's can travel some tens millions ly, which would make cluster appearance pretty unrecognizable. We cannot look at background-radiation anisotropy since it's picture would differ unpredictably for a region so far away. **What we can do** is to look for large-scale structure of the cosmos. [Great walls and superclusters](https://en.wikipedia.org/wiki/Hercules%E2%80%93Corona_Borealis_Great_Wall), [Large quasar group](https://en.wikipedia.org/wiki/Large_quasar_group), [supervoids](https://en.wikipedia.org/wiki/Bo%C3%B6tes_void). With this we can narrow region of search to some hundreds of millions ly, locate Virgo Cluster, our galaxy, and then [look for the Sun](https://worldbuilding.stackexchange.com/questions/91713/stellar-navigation-for-dummies-finding-your-way-home/91722#91722). Those large-scale structures were born from fluctuation of density that happened at the very beginning of universe so they are long lived by definition. They are hundreds and billions ly across so peculiar movement of galaxies does not change them much(even 1000 km/s for 6G years is only 20M ly). They would look a little different to our astronauts because of distortions caused by expansion of the universe but this is easy to adjust for. [](https://i.stack.imgur.com/mZLL2.gif) [Answer] Six gigalightyears is halfway to the edge of the universe (13.82 billion light years). That would create a very large obstacle for astronauts looking to find their way: they would be looking at a night sky about 6 billion years younger in the direction opposite their travel and 6 billion years older in the direction of travel. We map the sky on Earth the way we see it. Many of the brighter stars have lifetimes of only a few million years, so they would either be long gone or not yet born, or at different phases of their lives (red giants, novae, neutron stars). Even galaxies may look very different over such a large distance. For example, at 4.5 only billion years old, the sun would not even exist in the night sky of the other world, 6 billion light years away. With back-and-forth travel to Earth available, it might be possible that something in the method of travel provides a rough idea of direction and distance. With that extra clue, you could start drawing inferences about what is what and eventually come up with a guess as to overall location. However, you could quickly build a new star map and determine where you are in the new night sky (not connected to the bigger picture). [Answer] In addition to James McLellan's [good answer](https://worldbuilding.stackexchange.com/a/99322/45387), I wanted to point out that while figuring out location is very, very difficult, figuring out the local time\* might not be. The CMB temperature should still be a pretty good indicator of "when" the astronomers arrived (and there are other global quantities that shouldn't depend on position which evolve very regularly in time that they could measure as well). If the astronomers traveled backwards or forwards 6 billion years, the CMB would be considerably hotter or colder than the 2.7 kelvin we measure at Earth - I'm not familiar enough to know how precise they could get with this, but they could certain determine any big shifts in local time\*. \*Local time meaning the "proper time", that is, the time elapsed since the big bang in that region of space. As you may know, defining simultaneous times in cosmology is pretty tricky. [Answer] **The simple answer to the question is: no.** This problem is wonderfully depicted in the otherwise bearly tolerable movie *Lost in Space.* Sabotage to the the hyperdrive and traditional Hollywood circumstances send the *Jupiter II* sailing through space to unknown locations where their "star charts" are useless. Why are they useless? Because it's the biggest 3D jigsaw puzzle of all time. Enough information about enough stellar phenomena must be stored in a database with enough computational power to crank through what is fundamentally an infinite combination of positions within the galaxy. It is helped somewhat with some POV references such as the galactic core and known pulsars, quasars, etc, that are unique enough objects that can yet show up at those distances... but still... *You need time to capture information. A quick snapshot of the sky to let the computer start chewing while you capture even more detailed snapshots, and even more detailed snapshots... with the downside that with every enhancement of resolution you are exponentially increasing the amount of computational time needed to find your position in the galaxy.* **The more complicated answer is: yes.** Given a good enough database and time, you can find your location. Except... **But the even more complicated answer is: maybe.** My knee-jerk reaction to "can you peer to the diametrically opposite side of the galaxy?" is "no." I suspect no technology can peer through the galactic core to the other side. (super massive black hole eating all the electromagnetic radiation...). Therefore, without expansion throughout enough of the galaxy to give you the vantage points for deep peering, there are spots in the galaxy you simply no nothing about. Use a portal to one of those locations and, basically, it's impossible to know where you are. *But, if you had the tech and the expansion time to peer around and see all the corners for mapping purposes, then the six billion lightyear jump is no longer impressive. You have likely expanded more than that just to see the galaxy's rear end... because obviously humans are at the front end of the galaxy, dontchaknow.* [Answer] I think the astronauts would take a two step process. The first step is easy. They need to get a background-radiation satellite mapping the sky on the other side. You might try grabbing an existing deactivated satellite like [WMAP](https://en.wikipedia.org/wiki/Wilkinson_Microwave_Anisotropy_Probe) or make another. Either way, get one on the other side and have it start mapping. While it's mapping, run a few experiments to make sure basic physics assumptions don't fall through. Toss a few atomic clocks through and try to find out whether they tick at the same rate as they do on the near side of the portal. Remember, this is new science, so you can never be too careful. When you're done, you should have a map like this: [](https://i.stack.imgur.com/BWtk2.png) This is the output of WMAP after 9 years. As many local effects have been filtered out as possible (such as the effect of our own sun's movement through space), leaving only the anisotropy that we believe is associated with the cosmic background radiation. This should be matchable to the readings taken on the other side of the portal. There might need to be some adjustments if timetravel was involved. Once you have this, you have a solid orientation anchor. You know what is up, down, left, and right. Next, I'd use a surveying approach. Take a look for quasars. We should be able to find more than enough of them. Once you have a good set of readings, you can start using surveying techniques to find the best match for the angles that we see on both sides of the portal. Once you have a solid match, along with those angles, now we should be able to figure out where we are, with respect to the quasars that can be seen from both places. Quasars are separated by several billion light years, so the angles should meaningful. If you were to travel a few trillion light years, it might be harder. [Answer] # Hard Yes Some facts and observations from other answers: * [Observable universe is 93 Gly](https://en.wikipedia.org/wiki/Observable_universe) * There would be a plane where equidistant stars are seen at the same 'time' 3 Gly away from both locations * Cosmic background radiation can be reliably used to establish orientation * There are few very large structures that don't change too much over the time scale we're interested in (between 0-6 billion years) Given enough time, a survey will find both the large structures and the plane where the stars are the same from both sides. Which is plenty of information to determine the exact location of Earth [Answer] It's trivial: our observable universe, in fact contains # only a few very large structures, which are easily identifiable. You'd just look for and identify the sloan great wall, the Bootës void, and the 3 or 4 biggest superclusters. (Obviously, this would take incredible telescopes and a few years.) *{Note that we already have "incredible telescopes". Read up on Europe's GAIA space scope, which is pure "sci-fi".}* Vashu has already included in his answer and overall map of our observable universe, which shows how obvious it is. --- Note. OP's question was not clear if the travelers were "instantly" transported in an FTL sense. ***If the travelers are instantly transported***, then as I explain it's trivial. If OP means moving billions of years in time, the question is meaningless. (There's no way whatsoever to predict where everything was/will be over huge time periods.) [Answer] As long as the astronaut has a map of the sky from Earth where stellar bodies are grouped by distance (like on onion peels), then geometry suggests that there must be at least one point, or more likely a ring in the alien sky that looks rather similar, if not identical to a ring of equal size from the Earth sky. Get the distance of the celestial bodies in the ring and you have the half distance from Earth (3bn light years in this example). AN algorithm to find rings with certain characteristics in the sky has been used to study and identify echoes in the background radiation if I remember correctly. [Answer] Well, assuming hefty doses of handwavium so the astronauts survive the radiation inherent in a wormhole, I believe it would be possible, although it might take some time. The secret is a total sky galaxy survey, backed up with a corresponding survey from earth such as has been/is being done by HST, Spitzer, and Chandra. Once you positively identify four galaxy matches with their red shifts, you can pinpoint the milky way (even if it's hidden behind another galaxy) and determine how much time has elapsed since you left home to transit the wormhole. I'll let an astronomer do the math for this one. [Answer] Yeah they would. They would just have to look for literally anything familiar in the sky. Once you find something you recognize you can then estimate your distance from earth using triangles. For example, you're on planet X. You see a familiar planet Y that is around 15 million light years away from your planet at 30 degrees from your planet - just assume everything is on the same plane, all that does is simplify the maths idea. You then walk through the portal. As luck would have it you can see planet Y and you recognize it, which means that the light is probably the same age, since you literally just recognized it. Now all you have to do is figure out what angle it is away from you, graph all your points and then find the missing distance from your new location to planet X. There are also light dating techniques you can get into as well so if can't recognize anything you could start drawing the universe from your position and eventually you might find an area that looks like what you'd expect an area you've observed from earth would look like at the time reflected by the difference in the age of the light. Admittedly, both of these techniques are somewhat iffy. It might be easier to just figure out how the warm hole works. Or... or... don't read this if you're easily triggered... or, you can just try to detect gravity waves and hope you detect a wave you've already detected on earth and then try to use that to estimate where you are. You'd have to assume that waves that look the same are the same, but it could be done. [Answer] You may be able to find out where the astronauts are from the wormhole itself. Suppose in your world that the wormhole has a direction and a relative time that a travel experiences while passing though. Suppose it take a X length of time to pass. If your astronauts could travel back and forth and accurately measure this time gap while in the worm hole they could relate this to the actual distance. Suppose 1 minute of wormhole travel is equal to a billion light years of actual distance or something like that. You could even measure the time in nano seconds if you want it to feel more instantaneous. If your wormhole is 2D you could just align the orientation of the entrance to the wormhole to get the direction your astronauts would travel. With the distance traveled and a direction your astronauts could get a good idea where in the universe the other side is. If you have a spherical 3D wormhole it might be more difficult to get the direction. Perhaps you cold play with symmetry that the wormhole opens up at a symmetric point on the opposite side of the universe like if I dug a hole though the earth in a straight line I would end up at a specific point on the other side. [Answer] The astronaut couldn't find out where he is or when, if he doesn't have data from the night sky on earth. He would need more than a Polaroid of the sky at night^^. I guess NASA won't expect that so they wouldn't put such data into space ships. But if they have a data link to earth (Think Stargate, where radio waves could go both ways, matter only one way.) and a strong enough telescope at their end of the portal, they could: Find a stars, a galaxy or a black holes that are the same distance from them and from earth. The light going out from them would reach the earth and the portal exit at the same time. If they find one, it would be easy to get your position relative to Earth by looking at how it is rotated. For example if you see the galaxy from earth at a 45° rotation. And from the portal at 135° you had a triangle with a right angle (a²+b²=c² and a=b). If they find more than one it would be even better. If they don't find anything at exactly the same distance with earth. Maybe something recognizable even if it is 2 billion years wrong. And than you could find the Milky Way and look for our sun. (There shouldn't be anything to see, since light of our sun has only travelled 4,5 billion light years, cause our sun is 4,5billion years old. But we should be able to see his sun, if it is older than 6 billion years.) Or some other light source that was old enough. If the wormhole also travels through time\*, it would still be possible to find something that has send the light at the same time out, and reached the astronaut and earth at roughly the same time. And you could find out that happened, because the calculated distance of the wormhole exit and earth wouldn't match. (You would need to look at something near us that is old enough that light reached the astronaut.) \*Well as long as the wormhole exit has light from stars come to it that also travelled to earth. check out <https://www.space.com/33005-where-is-the-universes-edge-op-ed.html> So it would be impossible to find out for the astronaut, if the wormhole would send him over 26 billion light years away (without time travel). So I would say it is possible, but if he is alone with no communication, he would need years, strong computers and a good (radio) telescope. NASA would probably need also years just to get the necessary equipment through the wormhole. [Answer] Yes, but not quickly and requiring a few assumptions. Essentially I'm expanding on other people's answers with more optimistic assumptions. The important assumption is that there exist enough uniquely identifiable objects in the sky, that is, objects that can be identified without Earth-centric context. I'm thinking of objects like distinctive pulsars, binary systems with distinctive variation, easily identified exoplanet systems, etc. With enough of these objects we would have a map of known objects in known locations at a known time. As pointed out in other answer, a system so far away only has a small plane of objects in similar enough states to be identical but that's fine. At the other end of the portal we survey the sky and build the same kind of database. Providing there's sufficient points in the first database we'd expect to find at least 1 point in common, which sets a common point of reference. Given 1 reference both planets are on a the surface of a sphere that radius from that reference, a good second common reference reduces it to the circumference of a circle and a third pin points. The range of objects can be expanding if we can apply some stellar mechanics... if we can estimate the size of a supernova from the star that causes it, or the size of the star from a stellar remnant, we can widen the range of possible matching candidates at the expense of certainty on each one. I'd like to think that with something comparable to Hubble we could try to match some galaxies. We don't need to match galaxies that are considerably off the equidistant plane, even a small distance off that shouldn't be too different. [Answer] The first step would be look at the local stars, maybe take a few spectrographs and decide you are not local, or able to recognise any near by stars. Then look for pulsars / quasars and decide you still cannot map any of them, cause over 6 GYs they either are not active or out of sight. The final option which may eventually tell you where you are, over a long period, is to very carefully study the standard candle supernova events. Eventually some correlation may be observed over events which happen half way between Earth and this new world. I am going to guess you would likely need to compare records over a few 100 years to get a really good set of events that you can confidently say are the same on both sides. ]

[Question] [ Imagine it. I've invented the single greatest thing since Fire. A machine that can turn matter into energy and energy into matter with almost absolute efficiency. Sure, it violates a couple of the laws of thermodynamics and yes, you can get around a couple of conservation laws, but it's otherwise perfect, and comes with one of the most elegant software design suites ever designed (courtesy of my genius, of course). I can make anything, copy anything or turn anything into a huge amount of energy using my wonderful device. Of course, I need to stop the government from discovering I have such a device, lest humanity accidentally destroy itself, and I need money to buy land, employ people and develop more technologies. To that end I shall pose as a humble waste processing company executive (If you have an idea for job choice feel free to include it), taking rubbish and waste materials and 'extracting' valuable metals and energy to sell to the grid from the 'burnt' waste. My ability to transmute matter must remain hidden until I want to reveal it while still being useful for making money, so just sucking in a few tonnes of air and transmuting it into gold (which I then have to sell, which is awkward) isn't an option. Neither is counterfeiting millions of small bills and paying them in to the bank. The goal here is to establish a power base from which it will be possible (and this is going to come up in later questions) to introduce this technology in a way that won't lead to humanity annihilating itself. I'm not worried about timescale (though sooner would be better, I don't want to die of old age before my plans come to fruition) and I need my company to be large (and wealthy) enough that further actions (such as buying tech startups and paying scientists) doesn't raise any suspicions. Don't worry about what happens once the company gets to this point. **What are the major problems that I will have to contend with from a non-scientific point of view?** Assume my massive intellect can take care of the science! For example: Will taxation catch me out? How can/Should I conceal my activities from my employees? Should I be worried about crashing the global markets? A quick note on the machine. To transmute matter in an area it must be entirely enclosed by a transmutative field. This could potentially be achieved using mobile emitters to spread the field out. I'm not sure if this will affect anyone's answer. It can also be used to 'scan' items within this field (essentially transmuting them into themselves and storing the information about their structure) [Answer] So, you are planning a rapid rise to power and wealth without it being so conspicuous that you draw attention from the people that could discover your secret. Should be easy for someone of your genius, right? Your primary challenge is that whichever "industry" you use for a cover, you **absolutely will draw the attention of competitors** in that area. The more powerful and established they are, the more they can and will do to investigate, infiltrate, block and hurt you. Let's use a terrible plan to illustrate some of the considerations for your plan. This is how **NOT** to do it: > > Producing Aluminium from ore is a very wasteful and energy-intensive process. Your machine does it way better, you so "rescue" a bankrupt company and start converting ore into Aluminium and selling it a low prices, undercutting all the competition. > > > This will fail quickly as there are only a handful of big producers across the world, who all use roughly the same process and get their ore at a number of known suppliers. They know *exactly* how much ore you should be buying, how much electricity, etc. When they contact your suppliers to find out how much better of a deal you made, they find out you're not buying that much ore, or electricity. They will suspect you're actually selling ill-gotten Aluminium, either stolen or from a country under embargo. This ensures a government investigation and that's it. Game over. Turning that situation around, here are the things to aim for when selecting an industry: * It should be hard to trace or measure the input resources for your products * Government regulation (environmental, licensing) is light or easy to subvert * There are no too-dominant parties barring your entry. * It is possible to have multiple smaller operations * Large profits are the norm, so that yours will not attract undue attention These goals are impossible to achieve all at once, so you need to go through several phases. ## Startup phase The assumption here is that you have a small capital, either pre-existing or generated through the machine, but no power/influence to exert. You need to stay under everyone's radar and in one place. The waste processing plant is an excellent start: * Your machine can masquerade as an new type of incinerator * You get paid to collect many different kinds of waste of uncertain composition * You can cheaply dispose of even highly polluted waste, coming up clean on any inspection. * You can sell higher volumes of "recycled" materials than you collect as that's very hard to trace or prove ## Expansion As soon as you have some positive business results, you use these to expand by getting a big loan or finding investors. Basically, the way every other business might do it. Don't just build identical plants, go for related businesses. Cleaning up polluted sites, "upgrading" your recycled materials to prime quality. If it looks like it takes a whole big messy factory to achieve those, all the better. Make a lot of noise about how you are cleverly combining processes to conserve energy and protect the environment, etc. The more related businesses you have and the more they buy and sell from each other, the easier it will be to extract money from them in a kind of reverse laundering of money. Rather than making ill-gotten money appear legitimately on company balances, you are going to make it disappear so you can spend it in different ways. *Note: Buy up a robotics company and a mining company. You will need these later.* ## Going global At some point, going international will be your best course, as it's much easier to evade scrutiny when no single authority can keep track of all parts of your operation. You will want to either select a country with a weak government (Africa) or mingle in with the biggest flows of trade (China->US/EU). Let's be brave and go for a corrupt dictatorial (but stable) country in Africa. You will need a sizable amount of money for bribes, but once you get permission to build your factory, there is little risk of "oversight" beyond regular collections of more bribes/protection money. You will want some combination of power-hungry industrial processes (let's say water desalination) and a "geothermal power plant". You sell water and electricity at cheap rates, building a good reputation with both the populace and the dictator, while secretly making a decent profit since you didn't actually sink all your money into drilling a well underneath your power plant. *Note: pay well for a small security force and have explosives ready near your machine. If the dictator decides to take your plant, blow it up and blame local extremists. Then offer to rebuild it if you are allowed to retain your own security force. The dictator will not risk a revolt by trying again.* ## Diversification While by now you have a reputation, it should hopefully be of a tech-savvy philanthropist trying to clean up the world, rather than of a dictator-loving businessman making obscene profits. You can use this to expand your visible operations, but also start investing some of your hidden money through third parties into unrelated areas, so that you yourself don't become too conspicuous. Do this until you have a diverse range of income sources so that it's hard for any one opponent to shut you down. ## Consolidation Now it's time to return to the advanced countries and risk the wrath of the big industry players a bit more. You will want to create some dependence on your services/products. Drinking water may work in the US, given the current drought in the southwest, but not nearly as well as in third world countries. In Europe it wouldn't do anything, but you would have an easier time entering the energy market, as there are more players and the energy industry is not as influential within the government as in the US. On top of that, you can set up factories in third world countries you are already established in and start shipping high-quality consumer products to the world, "buying" raw materials from your other businesses and using "robots" to minimize labor costs. All this time you need to delay investigations and hold off hostile actions from competitors. Go on the offensive whenever you feel seriously threatened. Your machine can produce almost any evidence you need (obtain a tiny sample of the real incriminating material, copy a lot of it), but be extremely careful in placing it. ## Revelation You now are in a position to reveal your great invention, save humanity and create global peace in a new post-scarcity society. ## Resistance Unfortunately, the governments of the world are absolutely not interested in letting you do any of that, because you threaten the status quo too much. They call on you to surrender your machine to the UN and blueprints as well. Laws are quickly passed forbidding creation, possession and use of your machine. Fortunately, your third world dictator friends may be slower to react as long as you keep the money tap flowing. All companies you publicly own are raided by the government agencies and competitors and after some close brushes with capture and/or death, you decide to you need a safer place. ## Finale You use the mining equipment and robotics tech acquired earlier to dig out a hidden base in a most unlikely location, a volcano for example. Your machine is now put to use duplicating an army of robots as you prepare to bring salvation to the people by force. Not long after, your robot army is successful in capturing most capital cities in the world, and the world governments surrender to you one by one (France first). You declare yourself Ruler of the World and use your robot army to force the people to enjoy the benefits of your machine. Resistance stays constant and costly as you clean up the planet, eliminate hunger, thirst and poverty and stabilize the climate. ## Aftermath You design a great interstellar spaceship using your machine and leave Earth forever, disgusted with the shortsighted, ungrateful creatures that humans are. *Okay, that last bit was not part of the question, I guess...* [Answer] Initially, don't use your machine to create end products, use it to create raw materials that you sell to other companies. For example, buy or create a real platinum mine (or any other high-value naturally occurring commodity) and run it as a real mine. Employ real people doing real mining to obtain real product. Just supplement it with large quantities of synthesized product and introduce it into the supply chain. You can undercut the competition enough to corner the market quite quickly since, unlike your competition, you *always* seem to be able to find enough of the raw material to satisfy demand... You don't have to flood the market with cheap product and in any case that would create suspicion since other mining companies would know that it would not be a sustainably profitable model- you just need to gently undercut and capture market share by being marginally cheaper and always able to meet demands. Customers would gravitate towards you and other mines would eventually die over time through being unable to compete, then you buy them as more "cover". Repeat the model into other commodities, being careful to always employ people to actually obtain your natural raw material so that there is no suspicion about valuable raw materials springing into being. Repeat until your giant corporation controls the global commodity supply. This might also appeal to your ecological philanthropy since you could, over time, ramp down the naturally occurring material, supplanting more and more of it with synthesized material, thereby conserving Earth's resources whilst simultaneously driving (or at least supporting) consumer expansion... You still need some "flexible" accountants though :) [Answer] ## Skip building wealth Rather than making yourself wealthy. Why not skip the wealth building phase and go straight into your real objective. After all, your machine can make pretty much anything you need. What do you need money for? ## Provide services For instance, your device could be used as the energy production for an exceedingly powerful rocket engine. Build yourself a spaceship and leave the Earth. It will make you quite safe from the prying eyes of investigators. When in space, your machine can make everything you need. You can form a colony. Sell space in your colony (or hotel) to wanna be astronauts. Now you are earning money completely legally. Government agencies will think all of your money is going to pay for your rocket but your actual launch costs could be minuscule compared to conventional launchers. Or go into environmental clean up. Shovel oil polluted sand in -> get clean sand & energy out. [Answer] You're on the right track. Disguise your invention as a smaller invention that fit the following criteria: * Improves lives. * Has minimal direct competition So for example, you could disguise your machine as a cold fusion plant. But that's hugely high profile invention, and there are a lot of energy producers who would be extremely interested in it. So it's likely that you'd be quickly exposed and your machine stolen and reverse engineered. Your idea of waste processing is solid, but keep in mind that it's also a heavily regulated industry - and for good reason. That means you'll be subject to a great deal of scrutiny and testing. Additionally, because you're handling toxic wastes the workers will need greater access to the machine. I think a better option would be [Desalination](https://en.wikipedia.org/wiki/Desalination). Water scarcity is a huge deal in much of the world, and it leads to lots of human and environmental suffering. You can repurpose your machine as a device that efficiently converts salt water to drinkable in bulk. This is a [huge deal](https://en.wikipedia.org/wiki/Water_scarcity), and would make you boatloads of money quickly while generating lots of positive press and global good will. Best of all it's probably not something that would be heavily regulated - as long as the output passes some basic testing, you're solid. **Handling problems:** * Claim it as a [Trade Secret](https://en.wikipedia.org/wiki/Trade_secret). Do not patent. * Set up the build process in an assembly line format so that no single person has any idea what's being created. Make it overly complicated - extra components that are misleading and don't actually do anything, for example. Have robots that you personally oversee handle the final assembly. Heavily audit the process, be extremely careful about components being marked as "failed" - you don't want someone to somehow get samples. * The device itself should be a [black box](https://en.wikipedia.org/wiki/Black_box). Salt water comes in, fresh water comes out. Make sure that the operation is extraordinarily simple. * Don't make it perfect. Presumably a real device like this wouldn't create perfect fresh water, so your device shouldn't either. Put in false flags - maybe your device is "bad" at pulling heavy metals out of the water. This will be a hint that will mislead those trying to reverse engineer your system. * Make it cheap. Make your money in volume, not in costs. This decentivizes people from trying to steal your device, since it makes it much harder for them to undercut you for a profit. * Be paranoid, create anti-tamper components for each device that destroy it and render it useless. [Answer] Here's my suggestion(based on the assumption that you start off with nothing other than your invention): **1. Generate an absolutely "off the grid" fortune:** Start off by duplicating some gold/diamonds that you can easily purchase in any local jewelry store. Replicate and sell some of those until you are able to purchase some truly precious stones. Duplicate gold, and those gems, and very discretely amass a small fortune. Smelt the gold into nondescript bars if possible. Selling any of these directly would attract unwanted attention, so the next step is **2. Get a damned good (and preferably shady) lawyer:** At this point, you need to do what countless "criminals" before you have done: launder your fortune. You need to find a firm that's willing to guarantee your anonymity and do the "dirty" work for you, such as putting the stones up for auction, or selling the gold to the kind of people who don't ask too many questions. The key here is not to be greedy: don't flood the market with tonnes of gold. Sell just enough that you built up a few hundred million dollars. **3. An "evil" lair:** Now that you have the funds, you need a base of operations. There's plenty of countries where money will buy you all the privacy you're ever going to need. I would buy a decent sized island somewhere remote. At this point you can build a secure facility and transfer your machine there. You should also hire world-level security experts and possibly a small army to ensure your security and privacy. Now you're ready to get serious: **4. Every overlord requires ...** At this point you should probably find yourself some minions. I'm talking about borderline genius business men and scientists who have, as others have put it, some pretty flexible morals - not in the sense of being evil, but who are willing to allow millions to suffer while they set up your empire - and make no mistake, what you're basically asking for is an empire that NATIONS can't touch. These people can recommend the exact businesses and facilities that you should buy in order for you to establish your cover at an international level. They would ensure that any venture you get into would do well, while not being so wildly successful that you would attract the wrong kind of attention. At this point you'd base your decisions on their recommendations. ================================================================== Edit: The reason I'm taking a "underworld" approach is because this technology is incredibly powerful, and ultimately dangerous. Anyone possessing it would only ever need one gram of a material to generate tonnes of it. Only one prototype device would ever need to be manufactured before being able to create as many of them as you'd like (including weapons). You would now be able to generate an infinite supply of nuclear fuel, weapons/ammunition, clothes, food, or whatever. How many people would that screw over? How many governments? The answer is **ALL OF THEM**. Literally 99.9% of the world's businesses would go bankrupt. Including the banks. You've just rendered anything other than R&D absolutely useless. How many people's jobs/educations would become WORTHLESS? Our current understanding of what makes someone "rich" would cease to exist. This technology would not excite people: it would **SCARE THEM**. Every nation in the world would desire to own it exclusively - it would put them at the top of the food chain permanently. How many self serving interest groups are there on this planet? Any one of them would have world domination at their fingertips. You COULD release the technology on the web and just "level the playing field", but then some terrorist would be able to replicate a nuclear device and end the world (or some such thing). That would be irresponsible. The only way to implement change is over time. To become so powerful that your changes influence CULTURE, and people's mentality. Frankly, the only thing I could think of is that you would start a space-tech company, and literally build a private base on the Moon - maybe even Mars. Then start a colony based on the new principles of material wealth for every individual, and encourage pure research of new and more advanced technologies. Eventually you would reveal your power to the world, and offer to manufacture a infinite amount of food and medicine for them - entirely off-world and ship it down, while not releasing the tech to anyone. Even then I can guarantee massive riots and protests as food and drug-manufacturing businesses simply cease to have a purpose, and millions are left jobless. This is literally one of those scenarios that sounds innocent, but has devastating consequences, and to which the saying "you can't make an omelette without breaking a few eggs" truly applies. [Answer] ## Hiring the correct people Let's face it: It does not really matter what your first company will handle with. It will *always* be profitable, because you have device which literally prints money. **You have to hire great accountant with flexible morals** Your accountant will have to juggle the numbers in order to make your company look "normal". Because if you screw something in your accounting, you will be inspected by [IRS](https://en.wikipedia.org/wiki/Internal_Revenue_Service) (or its instance of that country) **You have to be good in money laundering** From the start you will have to make the "made up" money seem clean. And you have to be able to hide such laundering well, because if you do not, the state might assume you are into drug business (which you actually could, because your device can *also* make any drug in the world, in lab quality). **You have to have flexible morals yourself** The money will get you to the power. But first steps of the ladder will be filthy a lot. [Answer] This is actually very similar in character to the Rynn series of questions on this stack exchange. Rynn is a "subtle mage" who uses her powers in ways others cannot always detect. I recommend doing a search for her name on Worldbuilding. Don't use the device to oppose people, use it to make their lives better. People tend to give a blind eye to strangenesses that are working in their favor. Also, randomize what you're doing. Don't always produce 1 gold bar for every pound of trash you take care of. Sometimes just product 0.2 gold bars or something like that. It makes it harder to prove that you're doing something hard. One particular similar story that comes to mind is Stranger in a Strange Land, by Robert Heinlein. He at one point has a religion where the services have an odd offerings process. The offering plate is passed around, if you can, you put something on the plate. If you're on hard times, you take some off, no one judges. If you had a similar system in place, it would be remarkably hard to prove you were doing anything clever with your invention without getting everyone in the congregation to all swear what they put in/took out of the plate each week. [Answer] You can't hide it. If you ever use the machine to improve any legit operation (like garbage dump), your company will immediately pop up on IRS and police radars as turning bigger profit than it should (other companies doing same business). They won't think you have a magic machine, they will be sure you're laundering money - and that's the kind of attention you don't want. Because what you're doing basically IS laundering money: you create assets out of nothing and then you're trying to pass them as legitimate income to introduce them into circulation. I think your best option is to create gold or cocaine out of thin air, sell it on black market and then use regular organized crime methods to launder the money. After you establish enough wealth, you can buy some cheap land, create and bury a whole lot of gold ore/raw diamonds/rare earth metals/any other valuable mineral, and then "discover" the deposits and sell/loan the land to a mining company (or establish own). Of course, that would also raise huge suspicions. Like everyone suspect that Russian diamond mine of Mirny is not a real mine but a front for artificial diamond factory (just because it's yield is unrealistically high). [Answer] Move to some small third-world country that is experiencing serious famine and start producing food out of garbage, human waste and other undesirable materials. Give that food to the country's government in return for them turning a blind eye on your other activities. Let the current leadership take the credit for solving the famine and use their gratitude to form strong friendships with key figures in that government. Create some gold and use it to buy farmlands within the country, providing a plausible source of where the food is coming from. Use your machine to transform the dirt of your farmland into the highest quality soil and bury several copies of your machine at keep points to produce water. Employ lots of people to farm your land and pay them in food. Add any excess to the food that you're giving the government. At all costs, stay away from accounting. Use money/gold only for land purchases and bribes. Food is a much better currency because nobody tracks it and no explanation is ever needed when it disappears without legal explanation. Suggest to your government friends that they should donate some of the excess food to neighboring countries when those countries have need. Let your country become a source of benevolence for the entire region. That kind of kindness is a subtle power, and little more than that is needed to bring stability to a troubled region. Once peace is assured, start buying farmlands in adjacent nations, get more friends in those governments, and let your food empire grow. Select a few of your smarter farm-hands and send them to world's finest agriculture schools. Pay their tuition so they can earn letters after their names, then bring them back to monitor food and soil quality and to manage your farms. Provide your government friends with gold to donate to your charitable organization, so that you can pay these homegrown experts in gold and food. You will need these experts to spread your empire, later in the game. Check your mindset : You have a machine that can create anything out of anything. Conventional tools of power such as money and gold, and even the concept of ownership should be irrelevant to you. What you should care about is the love of your people and the power that that love gives you over them. Keep fueling the food economy, making sure that everyone within your sight is fabulously wealthy in their stomachs. As your countries prosper, members of the old global power-base will of course take notice. Let them. They will send in their investigators and find that your charitable organization is solving real problems, apparently through nothing more than good farming practices. Now is the time for you to send your experts out into the world, volunteering their knowledge and spreading your power. Stay out of the first world. Big Food is already playing a very similar power game there, so you need to stay off their radar. Instead, help all of the smaller, poorer countries in the world to become self sufficient and slowly devalue the premium which fresh water and food currently enjoy in those places. Keep making government friends. Again, do as much as possible, without using money. You don't need to own a solution to have it give you power. You just have to be known as the source of that solution. That gives you subtle authority over it. If your goal is the absolute power necessary to announce your machine's existence safely, there is no better path than making all other forms of power meaningless; and the easiest path to doing that is to feed and thus empower all the people. Nothing generates greater loyalty and allegiance than the filling of a formerly empty stomach. [Answer] # An Old Proverb To use a old Greek Proverb > > "It is twice as hard to crush a half-truth as a whole lie" > > > To that point start with a half-truth, say you have inefficient way to convert matter to energy. Use some sudo-science to make it impressive but not that impressive, eg. it requires a complicated reactive agent, it explodes every time, etc.. This gives you a nice cover to build on while also meaning no-one will feel threatened enough to seize your invention / kill it. ### Starting your empire Now you are known, perform a funding round to create a "incinerator" plant using the new technology (crowd funding may even be possible here if you label it as "Green Energy" etc.), also start an R&D department to research further improvements for the technology. Doing this should result in excess energy in your machines, some of this you could push into the grid but not all of it. So tell another half truth state you have found a way to leave useful materials behind (raw metals and plastics), you can fudge any tests performed by actually doing so and when in use just generate excess material. This means you should be generating a nice profit without anyone thinking anything is up. ### Next Steps While doing this have your R&D department looking, and collaborating with other labs about projects that can be improved with increased energy. Keep the power generator research in house as much as possible, to maintain control over who uses the technology (for example you can use it to limit research into areas you are going to make irrelevant). This will have the effect of keeping your researchers busy, making the world more dependent on you and reducing the economic and social impacts of unlimited power when you release it fully. You can focus on slowly improving the efficiency of your technology and then have *your lab* create a very inefficient matter generation machine. ### Repeat and Rinse Do the same thing with matter generation and with power, improvement can follow a exponential curve as the world gets more use to the technology. [Answer] I'd get into hospitality and counterfeit wines and spirits. Fine wine can go for **thousands** per bottle. It's very hard to counterfeit pre-WWII wines, because modern bottles contain trace radioactive elements from atomic blasts. You can create convincing pre-war bottles. Hell, you can create convincing pre-war wine! Whiskey is similar: you can convincingly counterfeit a $200 bottle of 25 year whiskey - for free! So start small with a restaurant or bar, and supplement your stock with your invention. Encourage your staff to give out lots of free drinks to encourage business. Fudge the accounting, and you just look like a successful small business owner. Once you've got the cash, buy another location. Rinse and repeat. Eventually I'd expand into hotels - you can create your own cleaning supplies, which should help your margins. It'll be very hard to pin down where the extra supplies are coming from, because you are actually buying spirits and soap and whatnot. Just not as much of it as you should be. Get a reputation for luxury, and keep a couple of truly marvelous bottles in every location. It'll get harder to fudge the accounting as your wines and spirits get rarer, but your margins are going to be fantastic. Balance the risk, and don't get too greedy. [Answer] ## Give it away for (almost) free * Develop a couple of "limited" versions of your device that are inefficient. That is, don't work as well as they could, but work better than might be expected. * Start a kickstarter to sell these, however when you deliver the final model make them less inefficient (software limited) and gradually increase the efficiency with software updates. * Once you have sufficient funds, and a large enough user base turn off the limiting software for everyone. Bonus points if you make it so the machine can make more copies of itself (and maybe don't let on this is possible until final stages). Suddenly we're living in post-scarcity society as everyone has access because all the altruistic people who bought these will make more and give them away, and eventually everyone will have them. [Answer] I'm sorry but I could not resist posting yet another answer here. Here is a sketch of a strategy that *works*. 1. Accept the inevitable: you *will* get noticed. So instead of hiding, become a media person who cannot disappear without noise. 2. Pose as a mad scientist/inventor, like Tesla. Make ridiculous claims, like you're working on colonizing other planets, or replacing aircraft with a net of tubes. 3. Start selling something high-tech, mobile, and power-hungry. Build charge stations here and there, and offer electricity for free. Don't forget cool solar panels at the top. Acquire accumulator patents and release them to the public - no competitor can beat replication anyway. 4. Go for a government contract, say for reusable rockets. Rockets are expensive. Land a couple (this is going to be tough), pretend you "examine" them, then just replicate the whole thing the way it was before launch. 5. In the meantime, buy an island in the sea, equip it with powerful laser guns and prepare to move there. No one can get you. 6. ??? 7. Profit! And hope you had a laugh reading this. :-) [Answer] I really can't imagine how you'll pull it off. As soon as a government of an English-speaking country gets interested enough, you'll have all five eyes in all of your computers, phones, etc. There's nowhere to hide these days. But there's nothing else for you to do. You have to take a stab. ## Go back to your home country It would help if you're an immigrant from a poor country. Or at least the child of one. Pack your bags and move to wherever you came from. Wherever that is, they'll take your fake dollars without asking questions. Stay low for a while. Have a good time. Make friends. You'll need them. Develop your social network by partying. As long as you're sociable, you'll get far by paying for the meals, the drinks, and the girls. Noone will care too much where your money comes from. You won't need to spend that much, anyway. Say you're a programmer and your *I'm Rich* app for the *Blackberry 10* afforded you a comfortable living. Eventually, you'll find agreeable business partners. They'll be your mentors, your protectors. They've spent years corrupting the system, and you won't need to worry about the "rules." Start simple. "Import" electronics. Or cars. Say you have other friends at the border who helped you avoid import duties. Stay simple. You have all the time in the world. Learn the ropes. Integrate better into this society. Make more friends. Be the mediator between your acquaintances. Someone needs building materials. No problem. Someone needs gasoline. Sure. You'll be the master of logistics, and everyone will be ready to cover for you. ## You're half-way there Already, you will have power. Power, ultimately, is political. It is these people. They who like you. They who will vouch for you. They who will step in for you and fight each other for their own sake in this corrupt country where everything is possible. Your fake money will be ever easier to produce and spend. You don't need to literally *launder* it in the sense of proving where you got it to a tax authority. You need to merely *psychologically* launder it, so that everyone in your circle believes it is reasonable for you to have it. Pretty soon, you can run for office. Your campaign will have plenty of funding. You will have plenty of friends. You will be a shoo-in for a member of Parliament. In government, it will be even easier to pretend to make money and further entrench your tentacles in the system. By now, you will have many business partners and many legitimate shady business dealings. You hardly ever need to use your machine, except to grease the wheels of your enterprises with more fake cash. As you rise to the top, you'll be able to take over and possess really substantial industrial properties. Properties that make oligarchs into billionaires in places like Ukraine. Mines, steel plants, etc. On their own, they're profitable enough. But you can do even better. You can manufacture ore, or natural gas, or end product. But as always, that's just to grease the wheels. Much of your wealth you take by force. You do what everyone else has done before you. ## Stage 2 ready for ignition You are at the top dog of a lawless place. Noone knows where you got anything or for how much. And noone asks. They already assume to know the truth. Even the NSA doesn't bother to dig deep. Not that they'd find much anyway. Your history is clean, simple, and predictable. [Answer] I'm late to the party but after reading some answers I guess you should not do all the hard guessing work on how to conceal or how to open up and let them know or what to share with whom first. ## 1. Build a spaceship and dress up as an benevolent Alien You stay in orbit and just swamp the Earth with your message of peace. You claim you have that technology which you already have and you are offering to give whatever is needed to humanity (just not the machine itself of course). Requests for service have to be peaceful, sustainable and help the humans. Every request is subject of a 30 days discussion period (on reddit maybe) and if no real opposit point is proven you fulfill that request. Introduce the guy (yourself) as your chosen buddy for some more personal gains. (Only point is how to start to build that spaceship since you might not be an expert in all the fields of knowledge required. For that maybe just win the lottery, create a charity and get some experts on that first. If they want in on that alien joke they could pose as your Alien friends.) On a second thought you might outsource everything of this and just ask the humans to come up with a way of making sure a request is properly thought out and restrained. ## 2. Create your own island Claim to have found Atlantis and made use of their ancient machine. Put a floating island somewhere in the middle of the Atlantic Ocean without disturbing the ship routes too much. Build an AI, ask her to devise a shield device and build that. After that you are pretty free to do whatever you please: maybe build a space elevator and many satellites (full surveillance). Ask the AI to make sure if somebody is about to do something against your Atlantis to notify you or/and to do something against it automatically. Some ideas from then: * Flood every city with a 'food-dropping device' so to extinguish hunger. * Offer transportation services with flying drones which can carry tons of stuff to remote locations for almost nothing. * In case someone wants to join you build two cities on your island (make it bigger if needed), one to get the people and evaluate them (AI should help devise a way) and then send them back or they can be a local citizen then. Come up with some easy rules and nobody has to hunger there and can do whatever he pleases. Once you have the correct people for your utopia you can always strap some rockets under the island and just fly away. [Answer] Ok, I'm going to go down a slightly different route that the other folk here. Like they say, keep it simple. **Step 1.** You say your device has a field around it in which it can work yes? How about setting up a whitelist of chemical configurations that are allowed within this field unaffected i.e yourself, your belongings, the surrounding landscape, anything you want to actually use to turn into something specific etc. Anything not on this whitelist is automatically turned into air. **Step 2.** You then announce to the world that you can do whatever the hell you want because you are essentially a god. Anyone that tries to get access to your machine, or bomb it, or basically anything else that you don't want to happen is turned into air and is not a problem any more. Granted, you'll have to stay inside your "safety field" for a wee while until your total control of the world is asserted, but, once you have proven that you are a benevolent god, the people will come to accept you. **Step 2b.** As an aside, you, with your nigh-on infinite genius, could probably use a mobile field generator to surround yourself in a similar field to stop any assassination attempts. And the best thing about it is that you don't have to create an evil robot army or anything similar to protect you as you are essentially invincible. [Answer] Another "brute force" suggestion to consider: Use the machine to transform the matter at a safe distance underground, at the edge of it's sphere of influence to the mobile emitters that you mentioned, then do this again for each of these mobile emitters and repeat the process until you have a network of emitters that spans the world (this will be virtually instantaneous), at which point you become in control of all of the matter on the surface of the planet. From here on you can do whatever you wish. Make crops grow in Africa, turn nukes into bunnies, Wipe away children's tears etc. The world, sir, is your oyster. And, should you decide to come out as the creator of this wonderful new world, if anyone questions your powers, you can instantly turn their genitals into an angry badger. Problem solved. [Answer] Switch any resource from the other plans with drugs or any other illegal commodity. Then you don’t have to “cook” your energy books. Anyone investigating you would already expect erratic book keeping due to the illegal substance. Your illegal activities would draw attention to your front men and potentially to you, but not to your technology. If you act through middle men and front groups you can distance yourself from any actual criminal activity. [Answer] Run an incendiary waste disposal plant. Turn a microscopic amount of the incoming waste into antimatter to boost the turbine output. Over a couple of years, gradually increase the amount until the energy production reaches absurd levels. You should be able to run most of the power grid after awhile. It will attract eyes, but they'll see waste going into the burn doors and power coming out the turbines. They won't see the machine embedded in the foundation beneath the incendiary chamber. Once you have a fair amount of money coming in, invest in rocketry, but not in the US. Kenya would be competitive for rocket launches if you charge low enough, and you've got a really good power source. They'll be expecting something's up if you overpower it too much but if you beat current rockets by 50% maybe not ... If pressed too far, you might be able to claim to have found a way to fuse D + D -> He4 as a hot reaction. A nuclear physicist would declare it hogwash (the reaction does not normally occur) but the gamma radiation w/o the neutron radiation would back up the claim until they look way too closely. [Answer] Another thing you can do if you're interested in good works without personal benefit and have already built up some money: Flaunt it in a restricted fashion. Build a 1GW powerplant out in the middle of some wasteland, power for sale for 1 cent per kwh. (Looking at the big nations of the world I see plenty of suitable ground in the western United States, much of Canada, much of Siberia and western China and other areas that aren't so tied to countries like the Sahara.) Anonymously announce the existence of the powerplants, the terms of using them are the government will not tax them and will administer an account for you--the money received from the power goes into the account, money will be disbursed in accordance with messages bearing your PGP key. Non-compliance or meddling means the plant shuts down. They are warned that the plants use antimatter and have anti-tamper systems--they don't really have antimatter (big safety issue!) but will blow up spectacularly if anyone or anything enters without the system being turned off first. Build for minimal maintenance and all maintenance is performed off-site--you simply lift the whole plant out with a space vehicle. Once you have built one you'll have no problem getting government cooperation to provide all the supporting infrastructure you need for others--simply announcing one is ready for placement will get you governments falling all over each other to help. The 1GW is simply a starter--make the later plants much bigger. Also, water--offer cheap desalinization. They built everything but the filter itself. I expect someone in a repressive regime will test the anti-tampers, after one plant goes sky high and they don't get any more for some years I don't think there will be any more problem. This allows you to do a lot of good before you reveal the technology. You can't actually make any money this way, though--for that I like Marv Mill's suggestion of salting mines. [Answer] One thing you might not realize is that this technology has the ability to create materials that are otherwise impossible to engineer. Instead of scanning materials and copying them, why not invent your own? For example, Gorilla Glass is a brand of glass commonly used in cellphones and tablets. Specially engineered internal stresses in the material cause it to be very strong. By your description, it sounds like your machine could achieve a much stronger material than what could be achieved by traditional engineering techniques such as supercooling, etc. Another example is carbon nanotubes and other nano surfaces. You could achieve unmatched efficiency with solar panels, lithium ion batteries, super-lightweight and super-strong materials for military purposes, etc. Start by manufacturing something for the military. Get a military contract. The US military is a STRONG ally to have. Start making space-age materials for them. Get them dependent on your technology. Eventually they will realize something is not quite right, and they will start asking questions. This is ok. Be open with them. Meet with the president, etc. Keep things low-key. Don't go public. Keep your production to a minimum and have a small group of exclusive clients. Keep your on-paper assets realistic. Purchase lots of raw materials, and use these in your fabricator to create objects made from the same materials, just to keep things realistic. [Answer] **Team up with the Venus Project and other utopian groups** They have the plan to build a new society, but lack the technology and resources to make it happen. You have the technology and resources but lack a plan. If you want to create a new society for the full benefit of all mankind, model it after the Venus Project. <https://www.youtube.com/watch?v=rvpTmiVhcxU> <https://www.youtube.com/watch?v=WuKPHQQ_IYM> **Create A resource based economy** If your machine can create almost anything for free, that would make capitalism obsolete, and you could create the perfect society with a resource based economy, where the people can have anything practically for free. **Build an underground research center/base of operations** Buy some land in Canada, and build a small or medium sized factory or research center in the deep forest. It has to be in a relatively isolated area. Then, buy all the land 10 kilometers around your facility, and surround it with a fence, and declare it a natural preserve. Build a single road to the small factors located smack in the middle of this area. What looks like to be a small factory or research building is actually a massive underground driveway to your underground base where you produce anything from new technology to food, to your own personal army of hi-tech robots. This underground base has to extend underground throughout the whole area of your natural preserve. Put carefully concealed cameras inside trees throughout your natural preserve to spot infiltrators. Put cameras and booby traps along the road lest anyone tries to drive in. Put wolves in the natural preserve so that they will live in the forest and take care of any infiltrators. Ship live deer into the natural preserve each week and set them loose. This place should be located in a mountainous area (preferably) so that It'll be hard to get to. Have carefully concealed communication antennas hidden in the forest **Build anti-gravity flying vehicles** Since your machine can create anything you want, you should create some anti-gravity flying vehicles. You should make them look like flying saucer-UFO's and secretly spread rumors of aliens to discredit sightings of your anti-gravity vehicles flying around the natural preserve. Dig a lake in the natural preserve and fill it with water and plant trees around it and make it look like a real lake. Build a huge opening hatch in the bottom of the lake. Have this hatch connect to the underground base. Build an underground hangar for the anti-gravity vehicles under the hatch. When the hatch will open, your anti-gravity vehicles will fly out through the water and out of the lake, into the air. Being anti-gravity flying vehicles, they do not need to travel through air like jets. Build a water-lock or else your underground base will be flooded. Modify your anti-gravity vehicles to be air-tight so that they can travel through water or vaccum. Modify them so that they can take you out into space and to your Moon or Mars base as someone else already posted. **Build a quantum computer** Make a quantum computer with your machine and put it in the underground base. This quantum computer will be able to decode the websites of all the organizations in the world. You will be able to hack into anything. This quantum computer could make a program that would calculate the future based on what you could do. Make the quantum computer decide what the best form of events you would take. **Build a fleet of spaceships** Using the anti-gravity technology, build a fleet of huge spaceships. Set your spaceships hovering over all major cities to intimidate everybody and declare your plan to the world. [Answer] For initial wealth generation, use gold. Make up to a pound but make it with a bunch of impurities, claim that it is recycled gold and send it to a small refiner to "purify" and stamp it for gold content. They will take 10-20% as their fee. Then you can sell it legally. You can't do that too much but you can use it to fund the next step. Find locations in California or other western states that offer mining claims (they still exist). Look at a geological map and examine the unclaimed areas and stake a claim in a likely spot that isn't too hard to get to. Then buy some gold produced in that area so you can get the correct impurities and isotopes. Then go there, use your machine to dig a bit and make a few pounds of gold that match the local gold. Send it to the refiner you used before. Sell that gold and buy some of the expected heavy machinery. Then go to town "mining" gold. Trade up to a larger refinery. Sell 10% of the gold for working expenses and store the rest with a name company like Goldman Sacks. So far, everything looks like normal operations. Anyone who investigates will see that the gold appears to be produced locally. If anyone physically investigates the mine (which means that you got very sloppy somewhere), they find a hole in the ground and you can claim that the current seam has been played out. Once you have a good amount of gold stored (and a good chunk of cash in the bank), you can start to get creative. Monetize the gold on deposit and use that to make trades. You can use these trades to generate quite a bit of wealth without touching your machine. Once you are legitimately wealthy, you can start diversifying into companies that use your machine. Personally, I would fund a rocket company to build a base on the Moon. Once there, if you vet the people who come up, you can use your machine relatively openly. You will then have a good defensive position from which to openly offer the services of your machine. [Answer] > > What are the major problems that I will have to contend with from a non-scientific point of view? > > > To succeed, you need to make humanity want to be saved by you. The issues are mainly social and economical, education, trust and willingness. These can be viewed from a scientific point of view as well, of course. So by "non-scientific", I assume you mean "outside of the science needed to build and operate the device". Your biggest challenge is to convince enough of humanity that you would be the best king. You need help from other humans. You can only win if your party is big enough. In democratic terms, you need to sway the majority in your favor. If too much of humanity is against you, you will not succeed, no matter the device. Your plan is to give this invention to humanity without endangering it. From a pessimistic point of view, I'd say that this is impossible. You simply can't not endanger humanity with this. Whichever way you think of, there's always a chance that humanity perishes. From an optimistic point of view, you want to maximize the chances of survival. The possibilities of a device like this are so far-reaching, you would need a world government to control it, some single entity with exlusive power over the devices' usage. If multiple parties have access to the device, suicidal or other undesireable tendencies of only one party might thwart the efforts of all others. Danger lies in individuals that currently have power, but, according to your question, you do not trust them to wield it in a "beneficial" way. My impression is that individuals who already have power are unlikely to risk losing it to someone whom they do not trust. So, you need to gain the trust of enough people, and those who already have power in particular. Some may not want to be saved by *you*, no matter what. To coerce these, you effectively need the support of the rest of humanity. Good thing such a device defies logic. Saves us the headache of having to deal with this problem in reality. :-) [Answer] This is inspired by [Fringe](https://en.wikipedia.org/wiki/Fringe_%28TV_series%29)'s powerful science and technology research company **Massive Dynamic**, whose motto is "what *don't* we do?" Start an organisation that legitimately does a lot of R&D. A *lot*. Your huge R&D budget would provide an explanation of how you can do things cheaper than the competition. At the heart of your business will be producing things that *in theory* don't require a lot of raw materials or energy, but in practice do not have any known economical production methods, such as particular drugs or highly pure materials. You would only undercut the competition a little bit and limit volumes so as not to arouse too much suspicion. But even with low volumes these things can be very lucrative because they are so expensive to make. Surrounding this would be many legitimate research and production endeavours. You will employ many scientists and engineers to work on legitimate problems, and you will have established networks of suppliers and clients that help you expand and find new opportunities. Eventually you will be in everything from superconducting magnets to siRNA therapies to nanotechnology. And this is your *real* cover! By diversifying and moving into more markets, more products, you are able to amass more land, wealth and power without sticking out too much in any one industry. Once you're ready to move to the next phase, you'll have factories of all sorts at your disposal, too. Due to all your high-value stock and equipment, nobody would question why you have tight security at some of your sites. You would also have many accountants and lawyers at your disposal. You would understandably have safeguards in place to protect your trade secrets and intellectual property. Although it's tempting to use the machine to cut costs here there and everywhere by creating raw materials and machines and eliminating hazardous waste, things won't add up and someone will notice. It is much safer to say "on level 4 we have an XYZ machine that uses a trade-secret process to efficiently create chemical B." Potentially the machine can be a fake, and every night you personally restock it with what it later dispenses (because why trust anyone else to do it?). If you're brilliant enough, you don't even need to use the machine at all... just legitimately use your genius to direct your researchers to work on things that you know will bring big results. But if you want to get there faster or the machine was a bit of a fluke, then you'll have to use the machine to help you get that extra cash flow that gives you an edge over everyone else. [Answer] The problem is you need a loyal agents of some sort. And you need to be aware of all the possible antagonists, and have a way to manage all the situations that may come up. If the world were as simple as it seemed to be before the middle of the 20th Century, with sovereign nation states and no fast long-range flying or orbital weapons, no Internet, etc, then it would be a lot easier. You could choose a nation that can defend itself, and form a strong alliance with its leadership, being careful to keep your own security strong enough that if someone takes over that country's military, they still won't be able to kill you or steal your technology. Unfortunately, in the 21st Century, it's hard to tell what all the actual powerful threats are. The counties are largely shells now, heavily corrupted by large networks of inter-owned/controlled corporations and banks which hold most of the planet's wealth and power, and which do what they do in part due to aggressive systems of ideas, but also by leadership and influence of many layers of executives, investors, and non-public figures (investors, friends, probably other non-public social groups of very powerful people). The nations and their military and espionage organizations are a dangerous threat, but those are known (listed on CIA web site) and have limited scope and influence. You need to have a plan for all the nasty string-pullers. Since you're an inventor type, and don't have time for that, one approach would be to get someone you trust completely to build a highly-trusted group of strong strategists and researchers to manage all that, and you need them not to be detected, and none of them to leak information. Another plan would be to figure out what you need for a research lab to develop sufficient defensive technology, and then arrange to do merely that. You find a likeable 3rd world country, and set up a research/manufacturing and/or energy company there, and get some contracts to do some work, so you get the equipment you need to do your real research and development as a small secret project within the operation, which you help fulfil its formal contracts well but not too well, to keep the operation afloat. I don't know how long it's going to take you to develop such further technology, but that should get you private lab space. [Answer] **Initial stage** Fabricate gold. Sell some of it. Use leftover as "gifts" to politicians for stage 2 **Stage 2** Say that you found cheap and clean method to extract elements from sea water. Let people think it's new kind of on-exchange resin but don't tell that directly. But you need to move to real production. Rent island from some country lake Greece (gold from initial stage helps). Order complex machinery which pump water via "reactors". "Reactors" will have only one secret part which will be well protected by self-destruction systems. Accept orders slightly below market price. Decrease you prices over time. Don't accept orders for nuclear materials without questions. Use money to help re-orient no-longer-necessary industries. Order 'airplane-without-engines' and later add engines based on your tech (just generate stream of helium or nitrogen...). You will need it if you want to escape. Talk to industrialized country you can trust about selling or giving you combat equipment, including anti-air systems (nothing fancy, just to surive first wave). Wait for some country to demand that your technology should belong to humanity and they will control it and attack you. Escape to Moon in your "airplane". Observe how they can't put production back online (self-destruction systems worked after all). Wait for UN to invite you back officially on YOUR terms. .... p.s. this is basically summary from Russian-language story at <http://samlib.ru/p/podolxskij_w_a/np-1.shtml> (their invention was "just" matter-generators, including anti-matter) ]

[Question] [ **This question asks for hard science.** All answers to this question should be backed up by equations, empirical evidence, scientific papers, other citations, etc. Answers that do not satisfy this requirement might be removed. See [the tag description](/tags/hard-science/info) for more information. This has been considered other places on the net, but I thought it would be good for the [hard-science](/questions/tagged/hard-science "show questions tagged 'hard-science'") challenge, since it is often an example of the subtle difference between soft and hard science. Okay, so you have your spacey ship in outer space. Then it is reported that space pirates have come to pirate our space goods. Time to turn the space stealth on! Is this possible? * The spacey ship needs to **keep the people inside alive**. * Ideally, the spacey ship needs to keep the people inside alive, and able to **carry out their normal duties**. * Ideally$\times 2$, the spacey ship needs to keep the people inside alive, able to carry out their normal duties, and **keep their sensors on**. * Ideally$\times 3$, the spacey ship needs to keep the people inside alive, able to carry out their normal duties, keep their sensors on, and **still able to maneuver**. The more Ideally's you get, the better. They also can't hide behind or [in front](https://worldbuilding.stackexchange.com/a/23249/8914) of things. You never know when space pirates are going to strike. The space pirates know how stealth techs work, so if there is a sensor that sense cloaked ships, that's the sensor they'll have, within reason (they probably wouldn't have gravity sensors). The only other thing is their sensors are passive, so they can't splash paint everywhere (space pirates have stealth too!) If any other details are needed, just ask in the comments. This is [hard-science](/questions/tagged/hard-science "show questions tagged 'hard-science'") physics and astrophysics (and for keeping alive, biology is needed.) NOTE: I suspect the answer is no. If the answer is no, the best answer would be the most thorough explanation as to why its no. [Answer] [**Forget it, there ain't no stealth in space.**](http://www.projectrho.com/public_html/rocket/spacewardetect.php#nostealth) The linked site explains in excruciating detail why stealth in space either do not work or is, when it works, extremely unwieldy or practically useless. I will shorten the arguments in the link * Vacuum means the only way to get rid of excess heat is radiating it or dump hot material. Remember, you need your crew and your equipment alive and working and not frozen, so you need to maintain a temperature difference between the warm inside and the cold outside. Super insulation does not help because you need to get rid of some heat at least to avoid being cooked alive. The problem is that temperature radiation sticks out like a sore thumb before the totally black space background. Heat radiation can be detected by a distance of $13.4 \cdot \sqrt{A} \cdot T[\text{K}]^{2}$. Lets make a very thin ship with $5\;\text{m}$ radius which has a surface area of approx. $75\;\text{m}^{2}$ which results in a factor of $116$. Freezing point temperature ($270\;\text{K}$) means the ship can be still detected in a distance of $8456\;\text{km}$ which is pretty far away. Once engines fire up (and you need to maneuver !), it is getting hopeless. [A single truster engine of the Space Shuttle can be detected at 15 million km range and using main engines it can be detected from Uranus. With current technology.](https://groups.google.com/forum/#!topic/rec.arts.sf.science/-E6r2F8rgnQ[151-175]) * Put something between you and the observer. Could work with planets and especially suns, but only if you intend to stay out of range. Putting a cooled sunshade between you and the observer could work, too, *if you know where the observer is* which is pretty hard because you are essentially blind. And because you are in inter*planetary* space meaning you are not moving straight it means sooner or later you need to correct the course which means engines -> back to first point. * A strategic usage of burn outside range and coast. The problem is that the space is vast, you have no idea if the enemy has already detected you and you need endless time (months, if not years) to get in vicinity. * Hope that you are literally lost in space and the sensors do not pick your ship up. This is *currently* a valid tactic on Earth because most instruments have a very limited field of view and there are interesting regions and uninteresting regions. That will change once spaceships are used and the article makes the convincing argument that with current technology whole area sweeps are possible in hours while traveling (especially coasting) will take much longer. Both sunshades and hiding will be especially useless once strategically placed sensor platforms are used. * Decoys are not of much use. There must be too sophisticated, expensive and too-much shiplike to fool even a standard enemy. Not impossible, but practically useless. EDIT: I must admit, Project Rho must be administered by a psychic the way he predicted the discussion. He already said that the second law does not allow to convert heat energy into another form of usuable energy to withhold radiation *without* further energy usage. No, you can't "grab" it with whatever your fantasy allows you to imagine, the idea is old and called [Maxwell's demon](https://en.wikipedia.org/wiki/Maxwell's_demon). Given the existence of [photonic metamaterials](https://en.wikipedia.org/wiki/Metamaterial#Electromagnetic_metamaterials) it might be possible to redirect heat radiation without active energy usage, but the metamaterials are non-perfect and will therefore cause themselves background heat radiation which will leak out. Answer to Ryan: Yes, using a cooled shade makes you blind. Your shield must match the cosmic background radiation which is unfortunately comparable to radiation of black body with $3\;\text{K}$. It means liquid helium and for deep temperature physics in this temperature range that means that even a human entering the laboratory gives off too much heat. Building passive sensors in the shade without disturbing the temperature will be therefore a severe challenge. Analogy: You want that I don't see that you are in the same room. Unfortunately I can see in the infrared range so cloaking will not work for the reason above. You can build a wall between us. Then I see this wall and while I don't know that *you* are hiding behind it, I know that the wall does not belong here. So you must prepare the wall that it looks exactly like the background. If you poke a hole in the wall, I can see that immediately. So at the end we are both blind. I think you also do not understand what these distances mean. Your space saga needs Faster-than-Light technology for travel between solar systems, else we are talking about thousand of years between star systems. Booooring. Even if we start from Pluto & Co. I presume your ship crew needs to eat, so you cannot start "billions of km/miles away". You *cannot stop in space*, every time you want to change your velocity it means engine usage and voila, I see you. If you start really fast and run cool after Uranus, you perhaps only need weeks but then you shortly see Earth and poof, it is already away. If you start slow, then you need some hefty stocks (the small area I used in the example will not hold anymore, increasing detection range) and a collection of board games because it will get frickin' boring. At Mike L: I think you are mistaken because there is [*no such thing as a lower barrier of detection*](https://en.wikipedia.org/wiki/Photoelectric_effect). If I point a CCD to a source, I can detect it if exposed long enough, it does not matter how weak the source is ( Otherwise it would not be possible to see faint stars/galaxies extremely far away). immibis proposed heat sinks. That could work but stealth in space has always time as enemy. To get anywhere you need time to cover distances because they are so vast, we are talking about timeframe of weeks and months. 1 normal human creates a power of $100\;\text{W}$ comparable to a light bulb which needs to be contained. Water is an excellent heatsink with a specific heat capacity of $4200\;\frac{\text{J}}{\text{kg}\cdot\text{K}}$ in fluid form and $\approx 1500\;\frac{\text{J}}{\text{kg}\cdot\text{K}}$ in solid form. It also has an extremely high enthalpy of fusion with $335000\;\frac{\text{J}}{\text{kg}}$. If we cool solid ice down to absolute zero and get the maximum water temperature to $60\;\text{K}$, $1\;\text{kg}$ ice can take therefore $273\;\text{K} \cdot 1500\;\frac{\text{J}}{\text{K}} + 335000\;\text{J} + 60\;\text{K} \cdot 4200\;\frac{\text{J}}{\text{K}} = 992000\;\text{J}$. 1 human will therefore need $992000\;\frac{\text{J}}{100\;\text{W} \cdot 3600\;\text{s}} = 2.7\;\text{h}$ of time to overload $1\;\text{kg}$. 1 month of travel time (which is really, really fast) means $240\;\text{kg}$ of ice. And that is when the ship is completely cold, no life support on and you are able to freeze ice down to absolute zero. Time is a friend for observers because the longer they can scan the sky with their sensors, the better they can even detect extremely weak signals. Using heat sinks means internal room which is also desperately needed for delta-V fuel (accelerate and brake). Increasing capacity will also increase the area and therefore the detection range. [Answer] I think the answer depends on the situation. * Space is *big*. There are millions of [asteroids bigger than 1 km](https://en.wikipedia.org/wiki/Asteroid#Distribution_within_the_Solar_System). We're not even close to having mapped them all, and they're not actively hiding. How do you tell a 100m ship radiating internal heat from a 1000m rock reflecting the sun? Spectroscopy, maybe. * Sensors can be active like radar or passive like telescopes. The energy received with passive sensors scales with $\frac{1}{distance^{2}}$, the energy received with active sensors scales with $\frac{1}{distance^{4}}$. That means active sensors have to be really big. * Passive sensors tend to have a very narrow field of vision. Not a problem if you're mapping natural objects, more of an issue if you look for a ship. * It will be impossible to reduce the radiation from the ship to zero, and the background is not suitable for blending in. * [hard-science](/questions/tagged/hard-science "show questions tagged 'hard-science'") drives will use lots of energy, and radiate it freely. That suggests to me it is very hard or impossible to *break contact* after initial detection, but making that initial detection is also very hard unless the ship radiates lots of energy towards the observer. [Answer] While the other answers explain very well the issues that stealth would have to overcome, I'm going to have to take a slightly different tack and say **it is possible**. **Heat**: Okay, purely using heatsinks seems to be out, unless the ship is very large. However, it is possible to collimate the IR output of a ship, and not by using a laser either (which would seem to violate thermodynamics). Instead, simply have a hot core which is exposed from just one narrow opening/tunnel/exhaust port. Anyone looking from the direction of the beam will see it; but anyone slightly off-axis won't. IR lenses are difficult, but IR mirrors are quite easy. Actively cool the port (or baffles along the edges of the beam), and also the outside of the ship. Use a blob of material that heat is actively dumped into (for example with peltier effect or similar), at the focus of a system of mirrors which collects and collimates the emitted IR. I think the IR can be collimated to about the same degree as a laser, and thus the odds of it hitting a sensor platform are quite low. This is not perfect stealth, but it is stealth for all practical purposes. **Drive**: The easiest stealth drive is something like a railgun, only used for propulsion. It can produce cold exhaust chunks (macroscopic particles, not gas - if needed, pre-chilled), and any residual IR would be hard to see because of the velocity. I don't know why everyone here is thinking *hot* exhaust... **Occlusions**: Okay, this is a tough one. Aside from some handwaving about metamaterials, I'd say the practical approach is to stick to a natural object that is travelling in the right direction. The exact size of a small object ought to be much harder to gauge from occlusions than whether it is there at all. Thus, practical stealth would involve brief runs in free space between convenient camouflage asteroids. [Answer] I hate to rain on the parade, but stealth in space is an absolute cakewalk. Generally speaking, if you put it up in space, it's stealthy. The most important detail about space, never to be forgotten, is that it is **big**. **Really big**. **Really really big**. If you can imagine how big it is, you're wrong... it's bigger. We do a pretty good job of tracking things around our planet. We track roughly [19,000 objects](https://en.wikipedia.org/wiki/Space_debris#Tracking_from_the_ground) with ground radar and lidar to make sure we know where they are. However: > > Most debris remains unobserved; according to the ESA Meteoroid and > Space Debris Terrestrial Environment Reference 2005 (MASTER-2005), > there are more than 600,000 objects larger than 1 cm (0.4 in) in > orbit. > > > So, if you look like an uncontrolled object (i.e. not maneuvering), you have a 3.2% chance of being on the detected list today. Now, consider that Low Earth Orbit extends out to 2000km. That sounds like a lot, but space is **big**. For distances within our solar system, we use Astronomical Units (AU). 1AU is equal in length the orbit of the Earth around the sun. Phrasing that 2000km in those terms, it's 0.0000133 AU. Not a very large region, in astronomical terms. But surely we can see you if you move. Then we know you're not an asteroid. Or do we? Consider that we are having trouble [detecting](https://en.wikipedia.org/wiki/Asteroid_impact_avoidance#Detection_from_space) asteroids large enough to cause extinction events. Space is so **big** that we have a hard time seeing things, even when they are a concern on the extinction-of-the-human-race level. Why is it so hard? Space is **big**. Passive sensors like IR sensors find their ability to sense falls off with the square of the distance. In IR sensing, the intensity (how much energy is being emitted) is not actually the part that matters. It's the irradiance (how much energy hits the sensor surface). For realistic space borne systems, it is not uncommon for the irradiances to be measured using femptowatts per square centemeter (fW/cm^2). At long distances, this can drop well below that unit, leaving it very hard to determine the brightness of an object compared to the thermal noise from the sensor. Multi-color systems can estimate temperatures, and better find "interesting" regions of the sky, but they're still fundamentally limited by noise. Active systems, like radar and lidar, face even greater issues. The return from an active sensor falls off not by distance squared, but distance to the fourth power (d^2 going out, d^2 coming back). It is nearly physically impossible to detect these return signals unless you know what you are looking for. By that, I mean you need to keep a continuously running clock with nanosecond precision while the signals are being listened to, so you can compare the signal received against the signal emitted. Clock drift limits the ability to do this. There are only two ways I can think of to have trouble with stealth in space: * Get close enough to reach out and touch someone. At that point, the stealth challenges are identical to those faced by stealth aircraft, because the distances are similar. * Use an engine that is especially noisy. For instance, if your engine sheds hard gamma rays, you can bet that result will be interesting enough for someone to take the time to narrow in on your position. [Answer] ## You can't hide the engines If we're assuming hard science no-magic-warp engines and ships that go places in years, not millenia, then the most visible part of any ship is going to be it's exhaust. In most natural planetary environments, there is nothing that could be confused with it. Some answers here are arguing that you might make a ship so "quiet" that can be confused with an asteroid - but that can be done only while not maneuvering at all. Even our current technology allows us to make an exhaustive list of any ships firing their engines in our closest star systems - I mean, there aren't any; but if someone used any engine capable of moving a sizeable ship (as per the requirement of some people inside, not a tiny probe; plus a capability for maneuver not the current practice of a single burn and airbrake because we don't have enough fuel to stop) in story-meaningful time - say, no more than a few months for interplanetary distances or less than a century for interstellar distances - then we already would know it. ## If you're seen, we know that you're not natural We can't do it yet, but there should be no issues for a spacefaring civilization to have a detailed list of *every* asteroid of significant size (say, ship-size) in their planetary systems, in the same manner that we currently track every baseball-sized piece of junk in earth orbit. Yes, there are many of them, that's why we have computers. We don't frequently get any new asteroids, and when we do, we can observe the collision that made it. If a ship that's otherwise indistinguishable from an asteroid arrived in some soft-science way, say, from hyperspace - then we'd still could get an immediate and automated warning from passive sensors that hey, we have a new asteroid that wasn't there yesterday. ## Once you are detected, you stay detected forever Let's assume that some pirate successfully robs a ship, gets some loot, starts running away and has the quietest most hidden ship possible. Well, we still know where exactly it is, and and rather accurately where it will be in next month or next year. The only thing that a perfectly stealthy ship can do is float in a straight line, and the moment it wants to adjust it's course, then once again everyone will know where exactly it is and where it's going to *now*. This also means that "You never know when space pirates are going to strike" is not really true - every space station would have an exhaustive list of every ship that is currently on route "nearby" (for very, very large values of "nearby" - passive detection of engines would work at longer ranges than ships with those engines will fly in a lifetime) as well as their exact routes, since you don't need their cooperation to obtain that, you just need to look. If you don't want to fly past anyone, then you don't. If someone fires up their engines to intercept you, then you notice that well in advance, and everyone else does as well, and is able to track the other ship to wherever it goes to. [Answer] **Edit:** @ThorstenS. convinced me that this is not a feasible solution (especially within the hard-science tag). So please do not take this answer into account anymore. --- Desperate times call for desperate solutions. Let's take space-time to hide our craft. You may have seen one of these graphs, that show how a 2D black hole would look like:  We assume now, that there is a device, that also allows to bend space-time, but instead of just piercing a hole in it, it creates a pocket. (The concept is similar to those of [pocket universes](https://en.wikipedia.org/wiki/Pocket_universe).) This pocket is still connected to the rest of the universe, but only through a very small opening. Inside the pocket the ship rests in an area of almost no distortion of space-time. The pocket can move (and the ship with it), and some minor interaction with the space around is possible. However, the larger the pocket opening is (to enhance interaction) the more probable is detection. In the best (most-hidden) case the opening between space and the space-time pocket is of sub-atomar scale, so that most traces, that the ship generates, will not leave the pocket. Is this hard to create? Definitively. And the amount of energy would be enormous, if no other means are found. But is it unrealistic? I think not. Space-time does some really strange things, like [creating vortexes around earth](http://science.nasa.gov/science-news/science-at-nasa/2005/16nov_gpb/). This makes the idea at least in principle feasible. [Answer] The [Revolation Space](https://en.m.wikipedia.org/wiki/Revelation_Space_universe) universe is at baseline the real universe with emphasis on Hard SF. That means no FTL. Then, Reynolds can add made-up breakthrough physics in moderation, careful to keep it "hard" by not doing things that would mess up real physics wholesale. One [item he has is for steathing](https://en.m.wikipedia.org/wiki/Technology_in_Revelation_Space#Cryo-arithmetic_engines) like you ask about: > > Cryo-arithmetic engines are a specific class of quantum computer discovered by the Conjoiners. When certain algorithms are executed on processors of this architecture, it leads to a local violation of the Second law of thermodynamics: the computer gets colder instead of hotter. Consequently, cryo-arithmetic engines have massive industrial (as opposed to computational) ramifications for Conjoiner manufacturing; such engines abound in Conjoiner asteroid factories, where their calculations can drain away the heat of starship construction. > > > Cryo-arithmetic engines are also used by the Conjoiner's modern 'stealthed' lighthuggers; they cool the exterior of the ship to the temperature of ambient space, making the starships difficult for the Inhibitors (or other foes) to detect. > > > This points out the big reason it is hard to be invisible in space: *heat*. More realistically, there are ways to stay cool for limited time periods. Endothermic reactions use chemestry to trade local entropy (in other forms) for thermal energy, and can work until you run out of un-reacted chemical. Superfluid and non-superfluid helium solutions can cool a chip to near absolute zero: if the entropy increase can be stored internally in a compact form (a black hole is the limit, and it's *way* up there) you can keep cooling the exterior until your sink is full. --- To hide camaflaughed against empty space means keeping cold. But now we have images like the Hubble ultra-deep field. A big enough telescope can see *whatever* is behind you (waaaaay behind) and note the eclipse. So look at the physical limits of that detection. If the exposure was short enough, the aperture would be very large. The ship, besides being a superabsorber in optical frequences, *could* mimic the appearance of faint red protogaxaxies in the background, but this requires knowledge of the observers position, both bearing and distance. The ship could be shaped or have thingies attached to make light diffract around it, being invisible enough to an observer with an aperture large enough to see the background pattern before you move out of the way. This might entail secondary structures keeping station thousands of miles away from the ship, in the same line as the observer. Such an extended arrangement *could* give general invisibility against a more normal, background of nebula and haze in a specific direction. [Answer] Yes. # Here is a list of what you need to hide from others * **Heat** Stuff (engines, people, appliances) produce heat. Even copper wires. * **Gravity** You ship has a mass, possibly large, therefore it creates a gravity field that can be detected. * **Electronic waves** (communications, leaks from that µwave oven, engine) * **Engine** Nowaday engines shoot burning gas. That's visible on many levels # How you hide it * **Heat** your hull must be completly insulated. You need to capture the heat in the ship, and either store it to use it somewhere, or, when there is too much, release it. One way of doing that is using a single laser. That laser will be visible, but only from a very small angle. It will also push your ship forward a little. * **Gravity** not much to do here. Lighter ships. Decoys (heavy stuff in a barel dumped somehwere). * **Electronic waves** Very insulated hull, avoid broadcast communications (directionnaly antennas or even lasers give much less to be seen). * **Engine** Ion drives (or even laser drives) and solar sails are better suited for long term space maneuvering. Shut them down when your course is set or when you risk being detected (no deceleration in space). They also have a much smaller signature, and capturing the heat produced back will limit it even further. Then there are active sonars (not sonars in space, obviously). The other ship would broadcast a wave, and see what hits back. You can detect that, and you can use the same principles used on earth to counter it (absorbing materials, mostly, but beware of not being absorbing too much stuff, as you'll gather energy from cosmic radiations that you'll have to evacuate). Finally there is simple optic detection. Obviously, not reflecting light helps, but if you are in front of a star, short of being invisible (which is possible, using sensors and projectors), you'll be in the spotlight. [Answer] **This question asks for hard science.** All answers to this question should be backed up by equations, empirical evidence, scientific papers, other citations, etc. Answers that do not satisfy this requirement might be removed. See [the tag description](/tags/hard-science/info) for more information. The closest you could get to stealth would be using metamaterials to confuse active sensors. Metamaterials are materials with properties engineered into them to change the refractions index in ways that are not natural. In theory, you could design a spherical cloak of metamaterial which would "bend" the light around in such a way that if you followed the photon, it would simply "slide" along the surface and continue on its way in a straight line. As far as the observer is concerned, there is nothing there, you would see everything on the opposite side and there would be no shadows or distortions to signify that anything strange is happening.(Interestingly enough, this principle can work with ALL wavelengths, a submarine can be protected from sonar and a building could be protected from the shockwaves of an earthquake with a suitable series of pilings driven into the earth around the foundation to reflect or deflect the shockwaves in the earth). In practice, metamaterials are made of very precisely manufactured "optical lattices" which can be thought of as something like a diffraction grating to bend the light the way "you" want. This is rather expensive so far, and also with current technology only works on a narrow frequency band. For example, you could make a cloak of metamaterial to deflect or bend radar, but the object would still be visible in optical wavelengths. It should be assumed that something so useful will be fully developed in the fullness of time, and eventually you could build a fully spherical metamaterial shell around your spaceship, and be invisible from optical and radar searches. Sadly, any working spaceship needs sensors, antenna and an engine, so there would have to be breaks in the metamaterial envelope. This would render parts of the ship visible to optical and radar searches. The metamaterial cloak would also have no effect on the issue of thermal radiation, your ship will still "shine" against the 3K background of space, and indeed the cloak might make things more difficult for the crew as heat builds up inside the cloak with no way to be radiated away (until the cloak itself reaches equilibrium with the ship). Since localizing the ship will be difficult on optical and radar frequencies, it would be useful to confuse the thermal signature. Having extendible radiators which can be moved would make localizing the ship a bit more difficult (think of the radiators as something like the bullfighter's red cape). Using a heat sink to store the heat in an insulated container would also work for a short while. If you carried a number of them, you could launch the hot container away from the ship in a random direction while heating up the next one. The downside of that plan is you will be carrying around a lot of extra mass for the heat sinks which you probably wanted for other uses, and once you run out of heat sinks or the heat sink material is saturated, then the game is up. So for some very limited cases, you could make it much harder to see the ship, but you could never become totally invisible. [Answer] ***"It is not possible". Or perhaps is it??*** --- ## (1) How enemy might detect us **(1.1) Active.** This is the active way of detecting. Enemy will emit some signal. This signal will interact with the hull. Iff hull reflects, then the enemy will pick up the signal. Analysis of the signal will identify our position, our speed, and possibly more data about us. **(1.2) Passive.** This is a passive way of detecting. Enemy will not emit a signal, at all. Enemy will just listen for signals. If we emit a signal, enemy will detect us. If we reflect from signal emitted by someone else (say.. sun.. or another ship), enemy will detect and gather data about us. **(1.3) Cast Shadow**. Other sources emit signals continuously at all directions. Say.. The sun. If the enemy is looking at sun, and their sensors detect the sun stopped transmitting its light in some small dot! Since the source emit continuously by hypothesis, conclusion is something is in between the sun and enemy ship. Something has been detected. Detection of cast shadow might be done with light of stars, sun, continuous radio emissions, etc. --- ## (2) Detection by EM Spectrum **(2.1) Radio and microwave.** RADAR is a system that actively scans regions of space, by emitting electromagnetic radiation mostly in microwave range, and hoping they will hit our ship and reflect back. Also, they might not emit any radiation at all, instead, they will listen for any emissions we do. If we try to contact someone using radio, we give away our position. Other radio sources that is emitting radiation might hit us, reflect from us, and enemy might listen. **(2.2) Passive infrared detection.** The enemy will try to look infrared signals. They are often released by black body radiation in normal temperatures. Basically, a thermal detectable signature because we have non-zero temperature. Also, other infrared sources might hit us, reflect and go to enemy, making us detectable. **(2.3) Passive visible light detection.** Looking.. maybe with naked eye. Or telescopes. Or whatever. We might be emitting visible light (lamps, engines, or whatever). Or, any other visible light sources (say.. sun, etc) might be emitting, hitting us, and reflecting back to enemy, which in turn it will detect. **(2.4) Detection by radiation of higher energies.** Cosmic radiation interacting with matter might emit photons, which can be detectable (to a ultra amazing high ridiculously accurate detector). Maybe we should ignore this situation. Or postpone to a future version. --- ## (3) Effective cloak. There are 4 possibilities of interaction of classical light and us: Reflection, Transmission, Absorption. In addition, there is the possibility we are emitting such things. * **(3.1) Emission.** We cannot emit any of these signals (radio, microwave, infrared, visible, higher energies). If we do, they will detect us. Its easy to avoid emitting radio, microwave. Infrared is tricky. Visible is easier. And higher energies is special. * **(3.2) Reflection.** We cannot reflect any of these signals. Its easy to avoid reflecting radio, microwave. Somewhat hard with infrared and visible. * **(3.3) Transmission**. This is the ideal. We must transmit everything. * **(3.4) Absorption**. This is good, but not good enough. With careful looking and amazing algorithms, the enemy ship might detect that some stars are disappearing and appearing back (because we are absorbing their light). The same apply with natural radio emission sources, infrared sources, maybe even X-Ray sources). --- ## (4) Microwave and radio cloak **(4.1) Emission.** Trivial to avoid. **(4.2) Reflection.** It is not that hard to prevent reflection of microwave and radio sources. The reason for this, its because their wavelengths are sizes we are costumed to (from meters to centimeters). By choosing the right geometry in your ship, to reduce RADAR cross section at maximum you can, you will avoid reflection. **(4.3) Transmission.** This is ideal, as we said. Thus we need to transmit the maximum we can. But it is somewhat hard to transmit radio signal, precisely because their wavelength is big. There are few ways of doing this. * (4.3.1) Making a ship transparent to this kind of radiation. This means, in all practical purposes, making a ship made fully of dielectric. Metallic or electrically conducting surfaces reflects this kinds of signals. Hardly feasible. And even pose some problems: By Snell law, the transmitted signal will shift angle and thus if enemy is far enough, we will be effectively blocking the source. Conclusion: (4.3.1.1) Offers good protection against active radar. (4.3.1.2) Offers good protection against natural sources. (4.3.1.3) Offers bad protection against shadow cast. (4.3.1.4) Unfeasible. * (4.3.2) Redirection. We can redirect all incoming radio signals, such that their Poynting vector remains unchanged from what it was before hitting us. (4.3.2.1) Using wave-guides, this is extremely hard precisely because their wavelengths is too big. A wave-guide that guides EM Radiation of wavelength $\lambda$ needs to have a size of approximately $\lambda$. Your ship would have to be huge and covered with wave-guides. (4.3.2.2) Using nice engineered materials (say.. meta-materials), this task becomes somewhat "simple" precisely because the wavelength is big. Some methods have already been developed **(4.4) Absorption.** Since transmission (the ideal one) is unfeasible, we shall place our hopes here. And thank for us, absorption is possible. * (4.4.1) Geometry. We can make the ship in such geometry to reduce active radar cross section at maximum we can. Then the signal of enemy radar will mostly be absorbed and be made undetectable. * (4.4.2) Material. There are absorbing materials that we can place in the hull, such that it will absorb incoming radiation. There also exists engineered materials (like meta-materials) made to absorb radiation in this range of frequencies. --- ## (5) Infrared cloak **(5.1) Emission.** This is terribly hard to avoid. Our ship emit infrared radiation because of black body radiation, which mostly fall into the infrared, using Wien's law. ) According to Wien's displacement law: $\lambda = b/T$, where $b$ is Wien's constant. If we decrease the temperature to shift from infrared to microwave, your temperature would need to be unfeasible low. In addition, you must radiate waste heat, if you plan the ship inhabitants/computers/equipments to survive. *To effectively cloak our selves, we need to make sure enemy does not receive our black body radiation.* **(5.2) Reflection**. Hard Hard Hard. *We cannot reflect from other infrared emissions if we plan to be undetected*. **(5.3) Absorption**. If we absorb, we must be careful with the shadow cast problem, so you cannot be in between infrared sources and your target. This is very hard in star systems. And hard in open space (since stars of course do emit infrared, and they are everywhere). Absorption only is dangerous and risky. *If we plan a good cloak, we cannot absorb*. There is only one left: We must transmit. **(5.4) Transmission**. Here we are. Its a must. If we transmit, we avoid active and passive detection. Our biggest problem is cast shadow: There is continuously emitting infrared source $S$, and enemy ship. We are in the middle. If the transmission is perfect, light from source will pass thru us if we didn't existed. If there is a delay, may be detectable if we are moving at an certain speed or higher. If it is not perfect (likely), there might be distortions in the transmitted light, and aberrations. If enemy calibrate their scans, they might detect this distortions/aberrations, and move to investigate (or perhaps to simply shoot at it, just in case). --- ## (6) Visible Light. **(6.1) Emission.** Trivial to avoid. Just shut down all the lamps in the outer-hull. **(6.2) Reflection.** We cannot reflect from other visible light emissions if we plan to be undetected **(6.3) Absorption.** Same argument for infrared. If we plan a good cloack, we cannot absorb visible light. **(6.4) Transmission.** Here we are. Its a must. And same argument of infrared applies to visible light. --- ## (7) What we need. **(7.1) Geometry.** Making things in the right geometry to reduce radar cross section and be invisible by radio and microwave. Maybe a fractal pattern. Or something to make the waves cancel out. I don't know. **(7.2) Infrared and Visible light transmission.** We need to perfectly redirect the infrared and visible sources as if we are not there. This is proving to be quite difficult with our current technology level. **(7.3) Black body Radiation.** Following (5.1), we need to make sure enemy does not receive our black body radiation. If you have hypothetical material that nicely does (7.2), then it will not heat up (since there is no conduction, no convection, only heating by irradiation in space, and (7.2) transmits everything, not heating it up). After some time, it will be as cold as environment. Since at principle you know where the enemy is, you can transform inside-ship black body spectrum into unidirectional beam, and waste it away not pointing the beam at enemy. That way, you remain undetectable, and you have successfully dissipated your waste heat. --- ## (8) Additionals. **(8.1) Keeping people inside alive.** (7.3) solves the waste heat. Life support system is not disrupted by any of this. Then, you can keep people inside alive. **(8.2) Carry out the normal duties.** Yes. There is no reason why not. As long as the ship is shielded internally (so radio signals from inside does not reach outside). And shielded infraredly and visibly (easy). Be careful as to your power source. It may release some kind of detectable radiation that might make its way to the outside ship (maybe neutrons, or gamma rays). **(8.3) Keeping your sensors on.** Of course!! You will only need to shutdown your active sensors (for obvious reasons). And leave only the passive sensors online (which is more than enough to detect an enemy ship). Enemy thermal signature alone might do the trick. And if enemy ship has active radar online, you can detect its position by the incoming radio signals. =). **(8.4) Still able to maneuver.** Tricky. Your engines cannot release any radiation at all. The only only way I can think off to accomplish this, is a special propulsion to operate in cloak only, which shoots projectiles. Very cold projectiles (temperature of background universe), which does not reflects radio, microwave, infrared, visible. Hard, isn't it? Perhaps you could engineer such projectiles to be such way: To cover the projectile with the same hypothetical material that keeps your ship cloaked in (7.2). --- Let me know where this answer can be improved. =). [Answer] The conventional wisdom has been for a long time that stealth in space is impossible, simply because it is impossible to hide your thermal signature. Which makes sense: after all, a spacecraft inevitably produce lots of heat: varied machines running even when the ship is idle, body heat from the crew (if any), heat from the electrical generator, heat from the engine plume - and the last two can be gigantic, particularly if you want your ship to go anywhere in a reasonable time. All this heat has to leave your ship at some point. Even if you insulate it as best as you can, it will still end up leaving your ship. And given the time scales involved with spaceships, delaying it a little bit with insulation will not change anything. However, a fellow named Isaac Kuo recently discovered a way to bypass this, with a concept dubbed the **Hydrogen Steamer**. Basically, while searching for some half-serious way to give brief tactical thermal stealth, he decided to try and use hydrogen, due to its fantastic heat capacity and heat of vaporisation. What he discovered, however, is that liquid hydrogen is not just that good at absorbing heat. It is much better. With the right design, you can keep a spaceship hull cooled down at 20 K for years, long enough for it to go anywhere in the system. And an object at 20 K is pretty much undetectable. Cover it with superblack material (like the commercially available Vantablack) and it can only be detected by occlusion, but due to the nature of light, this only works at very close range. **But what about the engines?** Indeed, such craft would be detected as soon as it light its engines, wouldn't it? Assuming it has conventional engines, this is true. It could still use low-efficiency manoeuvring thrusters to make small corrections to its trajectory, making interception more difficult. This would for example give a missile or attack drone considerable advantage as the defenders would have a harder time getting a proper firing solution, even knowing it is coming. However, it is also possible to have relatively decent "cold" engines. The trick is to take a conventional hydrogen engine (for example nuclear-thermal) and give it an enormous expansion ratio - meaning the throat of the nozzle is tiny while the nozzle is gigantic. That way, the hot hydrogen that is coming out of the heating chamber will expand considerably before exiting the nozzle. By expanding, it will cool down (while retaining its velocity, so it will still push the craft anyway). With a huge enough expansion ratio, it will cool down to be practically invisible, like the craft itself. As it is hydrogen, you cannot detect it by watching stars for new diffraction lines: most of the Universe is hydrogen already. Compared to conventional engines, it will be heavy and have a pathetic thrust-to-weight ratio, but it will have good enough specific impulse (aka efficiency), and you don't need a big push to move your craft in space, only a long one. ## So yes, to the general surprise, stealth in space is actually possible! More details on the concept of Hydrogen Steamer on this ToughSF article: <http://toughsf.blogspot.com/2016/10/the-hydrogen-steamer-stealth-spaceship.html> The only way to detect such a ship is with active measures like radar, but those can be defeated with conventional radar stealth techniques. They are not quite the same than with stealth aircrafts, but the principles are similar. Note that such stealth, while making detection considerably more difficult, is not perfect. But this is the nature of stealth, the same way stealth aircrafts can still be detected under proper conditions. A Hydrogen Steamer would be akin to a modern diesel-electric drive: limited autonomy, rather bad performances for a warship, relying on stealth and surprise for both offence and defence, and once detected, it is pretty much dead if any conventional weapon platform is close enough to engage it ("close enough" potentially meaning interplanetary ranges). [Answer] The most likely sensor of space ships will be radiation detection. There is radiation everywhere in space, but closer objects will not produce random noise. It will be more predictable and more intense. Even if technically a space ship has no moving parts, it still can't exist at 0 kelvin, so heat radiation is still released albeit in small amounts. You can heavily insulate the ship so that the outside will get as cold as possible to reduce this signature, but even a reduction in radiation received is an indicator. You'd of course need an onboard computer capable of analyzing radiation received in real time and notify of signatures coming from anything relatively closeby (within 1000 kilometers). To fight this, your ship would have to emit background radiation to mask the radiation that the ship is emitting. The crew could operate onboard without interruption and anyone detecting the signal would see only background radiation. So a secondary sensor might be an optical scan. The ship would use a telescope, and when used in combination with the radiation sensor, the ship could focus on anything minutely off. The optical scan would be able to determine the existence of an object by deliberately putting a star behind it in the line of sight. If something is there, the light will be blocked and you'd know that there is a ship emitting background radiation and likely a pirate of some sort. Of course you cannot observe everywhere at once, so you'd first have to suspect a strange radiation signature (even minute) before you can investigate further. Suffice to say that detection and stealth would depend largely on the capabilities of your onboard computer to emulate background radiation and the other ship to detect anything strange, but my guess is that a ship could get fairly close before being detected (within a kilometer) if it is trying to be stealthy. My guess is that if the technology existed, every ship, not only pirates would equip a stealth drive to emulate background noise. The trick is knowing where to aim it, since I don't think it would be possible to emulate it in every direction simultaneously. This means that the first to detect the other is the one that has the biggest advantage, and so the name of the game is having the best detection system in order to stay alive. [Answer] **This question asks for hard science.** All answers to this question should be backed up by equations, empirical evidence, scientific papers, other citations, etc. Answers that do not satisfy this requirement might be removed. See [the tag description](/tags/hard-science/info) for more information. Yes it's possible, but not in the way most of the responses I've seen are thinking. As some users have outlined, it's impossible to truly hide your existence in space. So what do you do when you need to essentially hide in plain sight? You blind the enemy without letting them know they are blind. The way I see stealth in space being a thing is that you would have to have extremely complicated and sophisticated hacking that essentially reaches out to any ship within range of sensing you and it ('it' being said program or effort) tells all of the observer's sensors that there isn't anything there. [Answer] **This question asks for hard science.** All answers to this question should be backed up by equations, empirical evidence, scientific papers, other citations, etc. Answers that do not satisfy this requirement might be removed. See [the tag description](/tags/hard-science/info) for more information. The primary issue, as many posts have noted, is the challenges of thermodynamics. In order to cool something, you must make something else hotter. When you radiate heat into space, you make space hotter and your ship cooler. Of course by releasing this radiation, you will be able to be detected. You could try to store the energy on your ship, but this has drawbacks that others have noted. **Alternatively, one very good method would be to *power your ship with negative energy!*** If you assume that negative energy is possible (you need it for gravity drives and stuff anyway), then you could store a large amount of negative energy and use it to provide power for your ship. In thermodynamics, energy flows from high to low, so by using negative energy your ship would actually be absorbing energy from the surrounding vacuum! **There would be a net energy flux into the ship**, rather than out of the ship. **As a result, your ship would not radiate heat**, but would instead be absorbing radiation from the surrounding space and be colder than the surrounding space. However, it could still be visible as a shadow against the background radiation. In this case, **in order to be stealthy, you would just have to heat up your ship to 3 kelvins with an auxiliary positive energy power system**, which you would need anyway to keep your crew from freezing. With this system, your sensors should work just fine. Whether or not your maneuvering would make you visible would depend on what propulsion technology you use. Assuming we are bending space, this would not give off radiation but could be detected with gravity sensors or by observing gravitational lensing around your ship. In general though, using a gravity drive would be much more difficult to detect than something like an ion drive. [Answer] Stealth in space cannot exist unless you can achieve invisibility. Stars in space do not twinkle and every spot in the night sky contains stars. The simplest sensor system would consist of high def cameras recording 360 degrees around the ship and a computer system watching for changes. Should stars suddenly disappear or reappear, it means something has moved in front of it and you can focus a telescope on it. [Answer] I am a passerby. Yet it seems likely that the question and answers above are misleading by using the term "stealth" as something identical to "cloaking." They are different. F-22 Raptor is visible in IR and even with state-of-the-art active radar systems in close distances. Yet F-22 is 'less' likely to be detected and 'less' likely to be hit by a IR-guided missile. Thus it suffices to be a stealth aircraft. (F-22 is seen as a size of a bird through rgular radars. No bird can fly faster than the speed of sound. Then, you might think it will be easy to point out the aircraft and track it. Sadly, the answer is no.) If any spacecraft successfully reduces its radiation to a degree that is indistinguishable from space debris, mechanical noise, or Asteoid. It is good to be regarded as stealthy. Also there is a issue with Rayleigh's criterion. To run passive and active radars large enough to see throuh the 'vast' space.... is nothing but impractical. Let's say a sapcecraft is equipped with a IR-detector with the diameter of 2.4m(equal to Hubble Telescope.) Rayleigh criterion says its can detect a heat source with an angular resolution of 0.1 arcsec at best. If the 2.4m-diameter detector uses the shortest wavelength IR, it will see a 100m-long object as a small dot until the obeject gets as near as 200,000km. 200,000km is closer than the distance between the moon and the earth. Whether it is far enough or not is a relative question. In addition, an asteroid with a diameter of 1km, traveling 2,000,000km away, look virtually identical. So do space debris with a diameter of 1m, traveling 2,000km away. Since it is possible to cool down a part of the spacecraft that faces the observer, while emitting heated-up exhaust chunks to the space. Such dust may go invisible immediately thanks to the limit of angular resolurion. How big will exhaust chunks be? Are IR radars capable of detecting such small things overcoming the vastness of the space? I am not sure... (English is not my mother tongue. Sorry for the grammatical errors.) Please correct me, if my caculation is wrong. [Answer] Use a counter measure cluster, one or more signature sources that produce radiation characteristics to your own. Send n of them off into space, creating a cloud of radiations at random distances away from your craft. Thereby producing stealth through obfuscation. A good example of this: Russia’s Vist-E torpedo decoy is a five-inch, 30-pound acoustic countermeasure that combines broadband noise masking with active sonar jamming and torpedo active reproduction. In other words, it can simulate a submarine's own narrowband acoustic signature, but has a relatively short battery life of less than 10 minutes. Overall, the Vist-E is less capable than modern NATO decoys, but when used in groups, it can create a field of confusion that will hamper most torpedoes. <https://www.thedrive.com/the-war-zone/33467/the-shadowy-world-of-submarine-and-ship-launched-torpedo-countermeasures-an-explainer> [Answer] Playing Devil's advocate for stealth here. One of the problems of stealth is that its hard to keep a spaceship at 2 Kelvin without radiating any heat. One solution is to use heatsinks to store the heat. Unfortunately, heatsinks cannot store enough heat in a reasonable time frame for a stealth mission (<http://projectrho.com/public_html/rocket/heatrad.php> see SECTION 3: STEALTH PROBLEMS OVERVIEW). However, I though of a heatsink that's probably not too handwavium that might do the job. (<https://vixra.org/pdf/1309.0201v1.pdf>) This pdf details "AB-Matter" which is a theoretical mesh of femtometer sized tubes of stable Degenerate matter which could be used to reinforce regular matter. One of the interesting details is in "3. Failure temperature of AB-Matter and suitability for thermonuclear reactor", which is that it would take around 10 thousands millions degrees to destroy the AB-matter mesh with heat. My idea being a heatsink that is is reinforced with this "AB-matter" so that in order to induce phase change the heat needs break the bonds of the Strong force instead of the intermolecular force. (Please do take this suggestion with a hefty amount of salt since I am not a nuclear physicist) [Answer] Stealth is possible, but tricky. One has to account for the noise floor of space, which is not perfectly black, as much as jamming. [MatterBeam of ToughSF did a *lot* of work](https://toughsf.blogspot.com/2018/04/permanent-and-perfect-stealth-in-space.html) exploring how to use coolant, very large wire radiators, and high expansion ratio rockets with conventional propellant to have quite effective stealth. Torch ship it is not, no, but it is very hard to detect from range. High expansion ratio nozzles and cryogenic coolants can also make missiles even harder to detect than the helium steamer above. One might well see their earlier stage with a sky survey, but once underway, good luck. Known ways to have low observability with radar in the present means you'd be stuck trying to find them with LIDAR sweeps or relativistic electron beam sweeps to see the scintillation returns. Stealth missiles are very doable. Theoretically speaking, a [Q-drive or Plasmadyne](https://tauzero.aero/wp-content/uploads/JBIS-May-2019-Greason.pdf) using very good superconductors could be quite thermally efficient, minimizing the heat output one has to concern themselves with, though detection radiuses for a whole sky survey or a more focused scan depend on too many assumptions to give concrete answers. The linked paper uses a linac as an electric rocket, which is harder to see than many rockets, but would create RF at the least, and interactions from the particle beam and plasma would also be detectable. A stealthier option such as [nanoparticle electric rockets](https://deepblue.lib.umich.edu/bitstream/handle/2027.42/76588/AIAA-2007-5254-110.pdf;sequence=1) could be even lower observable as well. As the dust (or macrons) deionizes there will be telltale but faint emissions, but not much thermal emission to worry about. Such a vessel might well want a second drive like the shuttered high expansion ratio rocket from the steamer in the first link, unless variable ISP could be developed to extend very far down to have higher thrusts, or just use it to help cool the rocket from time to time. Less conventional emissions such as whistler waves and the whole gamut of plasma waves could also be detected, but tend to be swept along with the solar wind downstream, so if you're closer to the sun than the q-drive/plasmadyne you will have a lot of trouble detecting it, unless the electric rocket is easy to detect, and it is using one. Jamming particularly sensitive instruments helps, though thermal emissions would need a supercontinuum laser, while looking for particular wavelengths like the spectral lines of a particular ionized element could be jammed with more normal lasers. Indeed jamming over an AU or more is conceivable with lasers in the gigawatt range, though this would mean you would have to defend your jammer. Also, I do not believe gamma emissions could be jammed at all, and x-ray jamming would be very difficult, so nuclear reactors and nuclear drives that might activate parts of the ship using either could give you away. Fortunately, if you know what your ship is made from, you can plan around your activation spectra if your setting allows for meaningful x-ray jamming. In all cases, full sky surveys generally detect things much closer than a focused survey would, but the sky is big, and you can't point your best telescopes everywhere at once. You're also likely better off mixing stealth with fast, "bright and loud" vessels that demand enemy attention too. ]

[Question] [ As per the cliché, after getting hit by a truck, our protagonist finds herself in a 'swords and sorcery' fantasy world. Also as per the cliché, she is granted an overpowered ability to make her new life easier. In this case, she gains the ability to summon/create anything she can imagine as long as she has a reasonable (layman's) grasp on how the thing works. Unfortunately, the world is on the verge of being overrun by the vile, undead minions of a group of necromancers. Having witnessed for herself exactly what kind of atrocities the necromancers are committing against the living (with suffering and death being powerful fuel for their foul magic) she vows to remove the taint of their existence from the world. Fortunately, she has played plenty of shooters and RTS games to have some idea of the weapons she can use against them. However, those are designed to work against living, human targets. # Available tech The world is a fairly generic medieval fantasy world. The enemy skeletons are limited in armor and weapons to medieval level. I'm thinking of equipping the skeletons with sword and/or longbow and wearing up to full plate armor. The protagonist has access to modern day knowledge of weapons and tactics. This includes weapons and tools that could semi-realistically be built with modern technology even if in practice the expense/complexity would be unfeasible. For example, remotely/AI controlled tanks and machine guns, and maybe even a version of the 'rods of god'. (If I find a way to justify summoning something not just in orbital position but having orbital velocity as well.) # The enemy Skeletons are animated dead. They are not so much dead bodies given life again as they are a conveniently arranged collection of bones whose parts are enchanted with magic to make them move again. Even if a skeleton is damaged, any separated parts will continue to move and act on their own. For example, a disembodied arm will use its hand to crawl along the floor and grab at opponents' legs. As long as any part is still able to move it will continue to try to harm the living in any way possible. A 'complete' skeleton will fight with any weapons it can find while any 'spare parts' will bite, scratch, grab and kick as able. This, unfortunately, means that it is not enough to simply remove the head or destroy the brain. Also, unfortunately, the undead remains animated even if the necromancer that raised them is killed. The sheer malice of the magic giving them life ensures they only stop when fully destroyed or rendered immobile. They are not mindless; their intelligence is at the level of an average human. # Summoning limits Without going into the exact mechanics, there are some general limits to the protagonist's ability. Apart from having an idea of the summoned object there is also a summoning cost in terms of energy user (think 'MP'). There is only so much MP that she can generate in a given time, limitting the size, complexity and/or number of objects summoned. Essentially, anything can be prepared given enough time, but on-the-fly summoning is limited to very simple, small items. # The question What sort of modern weapons could the protagonist use against skeletons, if the goal is to destroy them as completely as possible? How would you destroy large groups in the open? What about enemies occupying a town when you want to keep the buildings and any innocents in one piece? What about clearing them out of a building without demolishing it? Note that the skeleton enemies will be actively fighting back and they will number in the dozens to hundreds. Being in melee range of them is generally a bad idea, so unless the melee weapon is particularly effective a ranged approach is probably preferred, though ammunition is a potential concern. Note that the engagement is one against many, not army vs army. Below are my own initial ideas. ### Melee weapons Bludgeoning weapons seem the most effective option, though I wonder how much physical strength would be necessary to break enough bones to take out an undead. The use of a powered exoskeleton (i.e. power armor) could mitigate some of the danger, but engaging in melee still seems like a bad idea. ### Small arms Pistols and rifles of sufficient power will break bones - if they hit and don't simply pass through the gaps in the skeleton or glance off a bone. After the torso or spine is destroyed, hitting individual limbs would be a lot harder too. Either a form of saturation fire or expert reflexes and accuracy would be needed. ### Explosives If my understanding of explosives is correct, it's the pressure of the shockwave that kills the target through internal trauma. That means that at the very least, performance against skeletons is (much?) worse than against living humans. ### Kinetic bombardment Useful against massed concentrations of undead. Basically, drop a mass of rocks on the enemy from as high as possible. Either artillery or aircraft drop something like the Lazy Dog bomb on the enemy. Though, like bullets, a lot of them would need to be dropped to ensure complete destruction of the target. ### Acids Throwing an acid or similar onto a skeleton might be easier than filling its entire space with bullets. Chlorine trifluoride comes to mind, which reacts violently with pretty much with anything, though this would probably not be safe for the user. Edit: I should have indicated this from the start (but mistakenly opted to try for a general answer), but I'm most interested in the situation where the protagonist is forced into a situation of needing to dispatch enemies that have occupied the building she is in. (Because I'm finding it really hard to come up with good solutions for it.) However, I appreciate answers on all scales. [Answer] **Shrapnel is your friend** A skeleton is in many ways a similar target to the types of barbed wire fences used in fixed defensive positions. While you can pound them with artillery and mortars, the most efficient way to create breaches in a barbed wire obstacle (if you can sneak close enough without getting shot) is with a [Bangalore torpedo](https://en.wikipedia.org/wiki/Bangalore_torpedo) - basically a long, thin tube of metal filled with explosive. This is designed to produce long strips of shrapnel flying through the air to cut through any barbed wire in the vicinity. They would do a dandy job on animated skeletons. (If the protagonist cannot visualise the actual manufactured piece of kit, they are easily improvised in the field with det cord, plastic explosive and three star pickets (the same type of star pickets used to create barbed wire fences, ironically enough.) Lure as many skeletons as possible into a prepared position and initiate the charge from under cover. If the protagonist must engage directly then she must remember one thing - this is not a video game and she only has one life. Against dozens to hundreds of enemies with longbows she will get unlucky sooner or later if she gives them any chance to hit her. So she must stay out of range (up to 300m for longbows) or in effective cover *always* and never expose herself to the possibility of being hit with incoming arrows. In case something goes wrong, she should get a helmet and body armour. Engaging an untiring enemy that is difficult to hit effectively in a series of hit-and-run battles from over 300m away will be challenging. In order to be able to withdraw quickly while carrying significant weaponry and munitions a 4WD is definitely required. (Tracked armoured vehicles require significant training to operate safely and effectively, so they are not a feasible option.) My personal suggestion would be a [HMMWV](https://en.wikipedia.org/wiki/Humvee) with a [Mk 19 grenade launcher](https://en.wikipedia.org/wiki/Mk_19_grenade_launcher) mounted and as much 40mm ammunition and fuel as can be carried. Whenever possible she should engage the skeletons from high ground and during periods of rain, both of which will have a significant negative effect on longbow effectiveness but will have minimal impact on the effectiveness of the grenade launcher. So that takes care of open ground tactics. As for weapons and tactics for when she is going to single-handedly take on the armies of darkness in streetfighting to rescue the innocents - she must never do that. Ever. No matter what. Because if she does she will die. If it is essential to go house-to-house then conjure up a bomb disposal robot (replacing the disruptor with a shotgun) and send that in using remote control. Or she can drive to about 300m away and fire prac rounds through the Mk 19 instead of HEDP if she can get clear shots, that way there is at least no fragmentation to kill friendlies. [Answer] What you need is a **mine clearance flail tank** [](https://i.stack.imgur.com/uJgB0.jpg) **Here is a [video showing it at work](https://youtu.be/oQK_a4aGNuc?t=53)** --- These are based on M4 Sherman tanks and still have the standard weaponry in addition to the flails. > > Fuel capacity 138–175 U.S. gallons (522–662 litres) depending upon > variant > > > Operational range 100–150 miles (161–241 km) on road depending upon > variant > > > Speed 22–30 mph (35–48 km/h) on road, depending upon variant > > > <https://en.wikipedia.org/wiki/M4_Sherman> --- **EDIT** The question has been edited to require the inclusion of hand-to-hand fighting. I have two suggestions: **1. A hand flail** [](https://i.stack.imgur.com/jWW8g.png) **2. A chainsaw** [](https://i.stack.imgur.com/HoWr9.png) [Answer] Use immobilizing foam to neutralize the skeletons and then the villagers can go in with hammers or similar and finish them off. This will be therapeutic for the villagers in that they feel they are getting to fight back and will ensure total destruction of the skeletons. [](https://i.stack.imgur.com/th8LL.jpg) To be sure once the skeletons are smashed up with hammers they should be swept up and burnt, ground in mills, or otherwise permanently neutralized. [Answer] The trouble when you ask for weapons is that people think of weapons. The sound of [Brrrrrt](https://www.youtube.com/watch?v=iOoeNTTF36E) is all very well in context but we're looking at an entirely different problem here. It's closer to toxic waste disposal than combat. Szczerzo has the right idea when it comes to small scale troubles and building clearances, pitchfork and a woodchipper is the way to go, but once you're in open fields you need something a little more industrial in scale. I present to you, the armoured D9R. [](https://i.stack.imgur.com/dvkjE.jpg) ([Wikimedia](https://upload.wikimedia.org/wikipedia/commons/thumb/b/b6/CAT_D9R-1.jpg/640px-CAT_D9R-1.jpg)) There's nothing in medieval combat for dealing with something like this in the field. It'll stop a cavalry charge dead in its path, skeletons mindlessly attacking are merely going to turn into bonemeal under the tracks. There may be a few stray hands crawling about the field afterwards, but that's for the woodchipper squads to clear up. [Answer] We here, in the Department of Skeletal Removement use pitchforks (and shovels) and wood chippers. You simply load preferred amount of skeletons on your pitchfork like in the instructional picture below [](https://i.stack.imgur.com/1XP8Q.jpg) And then load them into wood chippers. For the extra sureness of bone removements you can sprinkle them with phosphorus or fluoride Always follow the safety rules and wear face mask. We don't want to inhale the bone flour. It itches in the throat for days. [Answer] > > How would you destroy large groups in the open? > > >  > > The Soviet RDS-220 hydrogen bomb, known by Western nations as [Tsar Bomba](https://en.wikipedia.org/wiki/Tsar_Bomba), was the most powerful nuclear weapon ever created (...), it also remains the most powerful explosive ever detonated. > > > This works best if blown up from a few kilometers above ground. Maybe summon it already up. > > What about enemies occupying a town when you want to keep the buildings and any innocents in one piece? > > > You can't save everyone, you'll always have casualties. Other than that: use a net launcher to snare them:  ... Then use drones to drag them into open fields, then:  > > What about clearing them out of a building without demolishing it? > > > Once again: 1. Net Launcher  2. Have drones drag them to the open fields 3. Boom!  4. ??? 5. Profit!!!! [Answer] ## **Engineering 101: keep it simple, stupid** ## Open-field tactics **Killing stuff** If her powerset is a literal "summon any known object immediately", then a top-tier skeleton removal tool would be a large slab of granite, starting about 10-30 feet above the ground and eagerly awaiting the call of gravity. This should render the opposition into some appropriate level of powder. If not, the several tons of rock on top of them will leave them immobile for some time. For extremely large slab drops, we might be concerned that the downdraft of air pushed aside during the drop could sweep skeletons out from the kill zone (bad). This can be fixed by lower drop heights, and/or by perforating the rock with holes to allow air to escape upwards rather than being pushed aside. **Avoiding being killed** Longbows do offer some nasty sniping opportunities. Being arrowproof at all times is well within the parameters by any modern ground combat vehicle (tanks, APC, etc...). However, you might be at risk of being swarmed in your blind spots, so perhaps an all-terrain pope-mobile with judicious application of granite-drops is easier. [](https://i.stack.imgur.com/2Mbgt.jpg) Or a helicopter, of course. Bit tricky to fly one though... ## Urban clearance Avoiding property damage by yourself means either getting the skeletons out of the urban environment, or turning yourself into a perfectly protected room-clearer. If the skeletons can be manipulated, blasting out a rock concert on the village green and then applying open-field tactics seems like plan A. If not, then this is not feasible by yourself. No man-sized suit of armour is safe from a sledgehammer. To say nothing of the time required to clear entire villages and towns room-by-room single handedly. Therefore I advise a political/God-queen solution. Arm some poor buggers and get them to do the dirty work. This can be as simple as riot gear and hand weapons, or as high tech as you like (I'd go simple, peasants may accidentally wreck their own town or get some assassin-y ideas if too well equipped). Extra carrots for your followers could be summoning antibiotics and working sewer systems. An extreme but effective solution could be using a megaphone to call the remaining villagers out of their town, granite-dropping the entire damn place to kill the skeletons, and then summoning a nice new town on top of the granite. [Answer] Forget military equipment, use construction equipment. A fleet of back-hoes to dig pits, bull dozers to shove them in, Dump trucks to drop in asphalt, you have a public works project that solves your problem for both roads and armies. The hot asphalt dropped down after the skeletons were pushed in would stick them together, trapping them in, if any were able to make it out, the bulldozers could take care of them. Or, steamrollers could flatten them. Mace-men could handle any that slip past, or climb up onto the vehicles. Plus, it adds a bit of comic relief to what could be built up as a terrifying situation. [Answer] First thing that comes to mind is [chain shot](https://en.wikipedia.org/wiki/Chain_shot). Two cannon balls joined with a length of chain. Originally used to bring down the masts of sailing ships, I imagine a volley of those through the middle of a skeleton horde would do sufficient damage that the shovel-and-cudgel brigade could then wade in for the clean-up work. [Answer] **For open fields:** Lots of good suggestions already, but one vehicle that immediately came to my mind and I haven't seen mentioned is a large snow blower [](https://i.stack.imgur.com/dIa1m.png) [source of picture](http://metroquip.net/equipment-sales/tu3-truck-mounted-snow-blower/) These machines are GREAT at chopping lots of material into small pieces and disposing of them. They're heavy duty enough to chop through blocks of ice, a few skeletons shouldn't be a problem. They're road vehicles, giving them a higher max speed and range than most tanks or construction equipment. Perfect for catching up to the hordes or escaping them. Add a little bit of armour and you're good to go! **For close range** I think Tim B and Renan had the best ideas with immobilizing foam and nets, and KerrAvon2055's suggestion of the Bangalore torpedo is most likely the best option you have in terms of using explosives. I don't have much to add on that. [Answer] Your best *simple* defensive weapon against a skeletal army may very well be good old-fashioned density. Bone is roughly twice as dense as water. Even naked, a skeleton would have no buoyancy at all and would quickly sink (armor would only make it worse). They can't reasonably move through water because without muscle and skin, they don't have a lot of surface area on their hands and feet to generate propulsion while attempting to swim. A moderate-depth moat would be an extremely effective defensive weapon against a skeletal army. Their only way across would be to walk across the bottom and climb on top of each other and out the other side. They can't attack you while underwater, and when climbing out they're extremely vulnerable to peasants wielding hammers. So summon up a big pile of shovels or a backhoe and dig you a skeleton-proof defensive line. Or summon a boat and move overseas. If you want a more complex skeleton-proof defensive weapon, summon up some doors with biometric locks. Fingerprint, retinal scan, whatever, the type doesn't matter, they don't even have any of that stuff in the first place. Without skin, they won't be able to get a lot of traction between their feet/hands and the pavement. They would be very susceptible to slippery surfaces. Build a steep ramp out of slick, polished metal that humans can climb with a struggle, and a skeleton will slide right off. Post peasants wielding a fire hose at the top for extra effectiveness/comedy. Pick them off at your leisure. If you put your skeletons in full plate armor like you suggest, then they won't be too much different than a human wearing the same armor. With a human, you'd use a high-powered compound bow, crossbow, or any modern firearm that can pierce through the armor. A human target could then bleed to death, but the best a plain arrow would do to a skeleton would be to lodge in a place where it restricted movement (less likely for a bullet). You'd need something like an exploding payload on the arrow to do any real damage, or close to melee range and use a heavy bladed weapon to sever limbs. For clearing/escaping a building, most of your fighting will be in melee range. A small shield and a hacking blade (like a machete) would let let you disable an unarmored skeleton attacker fighting 1v1. A heavily-armored skeleton would be slower than you, so keep just out of its melee reach and blast it with a shotgun. Aim for shoulders and knees to prevent them from attacking or giving chase. Once disabled, disarm them and wait for the hammer-wielding cleanup squads to finish them off. Speaking of arming peasants, a scythe could be useful for taking the legs off of a skeletal attacker. Your peasants likely already know how to use it, too. At that point, the skeleton is vulnerable to hammers and has limited ability to attack. If you want to go extremely unconventional, summon up some highly-trained herd dogs. Your local peasants will already have herds of cattle, horses, buffalo, etc. Use the dogs to stampede the livestock directly towards the oncoming hordes, and watch them get ground into dust. [Answer] Can you summon a vehicle? If so, a steamroller seems the easiest. Drive over them, watch the dust fly away. Otherwise I would just summon a 40mm grenade launcher or perhaps a mortar, conjure up ammo and you are good to go! A first salvo will shatter the hit skeleton and make the surrounding skeletons fall apart or to the ground. The next salvo's will make them even less dangerous. Repeat till destroyed. Mortars also have the advantage of no LOS firing. The biggest advantage is how extremely simple these things are in comparison to most other weapons. Or perhaps shotguns. Shotguns can tear bone apart, and automatic shotguns would basically function as ranged hammering on the skeleton. [Answer] **White Phosphorus** The temperature at which bone is burnt to ash is around 1600 degrees Celsius. White Phosphorus burns vigorously when exposed to air, is sticky, and burns hotter than thermite, at around 2760 degrees Celsius (5000 degrees Fahrenheit). I am fairly certain WP munitions will make short work of skeletons. I tried to look up how long it would take their bones to burnt to ash, but couldn't really find anything. Just don't use it close to you or in any building that could burn down. And don't breathe the fumes; repeated exposure is known to make your jawbone dissolve. **Edit: Other extreme heat technologies** It has been pointed out that WP burns at 5K *Farenheit*, not Celsius. That error means WP is only 1000 degrees above the decomposition temperature of bone, which may not be fast enough. Either of these two burn much hotter: A [MIG welder](https://hypertextbook.com/facts/2003/EstherDorzin.shtml) requires power and a gas supply, which imposes limitations on its use. But it produces a plasma stream which ranges between 6 to 24 *thousand* degrees Celsius. Even with full-on welders' gear, I wouldn't want to try to fight hand-to-hand with one, but channel your inner Kevin McAllister and set up point defense booby-traps. Booby traps involving a combination of [dicyanoacetylene](https://en.wikipedia.org/wiki/Dicyanoacetylene) (burns at 5000 Celsius) to be set off via conjuring some [liquid oxygen](https://en.wikipedia.org/wiki/Liquid_oxygen) from... As far away as you can get would probably be enough to get rid of your skeleton problem. They might **also** start an inferno that gets rid of much of the town. **Edit: Incendiaries have a big drawback** Basically, you can, if you look hard enough, find incendiaries we either have today, or could figure out how to make (if we needed it desperately enough) that are energetic enough to destroy a bone skeleton quickly enough to save the day. The problem is anything vigorous enough to do the job will necessarily pose an extreme fire hazard to anything flammable, specifically to wooden buildings. Even dust-grain sized droplets of burning dicyanoacetylene, or liquid oxygen, can land on tinder and there's a good chance your hero is going to have a bad day. And the skeletons will likely thrash around enough to cause such spraying. Works great in stone buildings. Wood buildings, not so much. [Answer] Given that the skeletal enemies seem to be animated as if they had muscles acting on their joints (and the bones aren't simply levitating, e.g. you don't need to worry about being bludgeoned by a single animated femur), then you simply need to break the skeletons into small enough pieces that they no longer have functional joints, or lack enough structural integrity to support their own weight. And although limbs can continue to function once separated from the body, they will have reduced mobility (and thus combat effectiveness) by virtue of the fact that limbs are not generally designed to ambulate entirely on their own. This means it is possible to deal crippling damage to your skeletal foes without necessarily having to completely destroy them. One ubiquitous modern weapon which might be suitable for this task without causing major collateral damage would be a large-caliber shotgun, loaded with buckshot. A buckshot shell sprays between 10 and 30 lead or steel balls in a tight cone, and would be more than capable of shredding a significant portion of a skeletal enemy at moderate range. Bird shot, which uses more pellets of smaller diameter, might also be suitable at close range. Shotguns have the advantage of being easy to use, ammunition is not difficult to produce (you don't need a high-tech industrial base), and you don't have to be a particularly good marksman to inflict significant damage to your foes with one. For large groups of skeletons where collateral damage is less of a concern, a fragmentation grenade would be more effective. This employs the same principle as the shotgun -shredding the bones with metal fragments- but on a much larger and more violent scale. It is *possible* to destroy the structural integrity of bones by superheating them or by applying strong acids or bases, but this probably isn't practical because these things require significant time (sometimes several hours) and, in the case of heating, copious amounts of fuel, which wouldn't typically be available in a combat setting. You *might* be able to pulverize them at short range using ultrasound, but again, this is likely an impractical approach. [Answer] Most ranged weapons will be worse than useless, the only thing that will be even moderately effective are RPG's AKA rocket propelled grenades, even normal grenades will be decently effective. they will fragment the skeleton. But they will really only be useful for getting away or for softening them up as a direct attack method they will leave the skeletons in relatively large pieces. If you don't mind going old school, cannon and chain shot will also be somewhat effective. they will rip through a skeleton as if it was not there, with some creativity it might be possible to create a modern equivalent. [](https://i.stack.imgur.com/m0V4t.jpg) A skid steer driven mulching mower, this will not only cut the skeletons apart but you can run it back over the pile to reduce them to nothing but bone chips. The open front combined with the crash bar means you can basically just run into the skeletons. The windows are designed to withstand flying rocks and branches a bow and arrow will not penetrate. A skidsteer is also a lot more fuel efficient than a tank, althou chasly's tank is also a good idea. [](https://i.stack.imgur.com/HVDGU.jpg) For close combat platemail plus a finned mace is your best bet, Once bone is removed from it protective covering of tendon and muscle it is relatively easy to smash. Honestly a baseball bat will work just as well. A pole hammer may be a nice choice as well, although you need a decent amount of room to get the best use out of it. [](https://i.stack.imgur.com/81TfV.jpg) Bolos and tripwires, will be good for knocking down the skeletons to make them easier to attack. Now if you want to get creative, your summoner could summon a Independent Tactical Thagomizer otherwise know a stegosaurus, which will be a able to smash skeletons quite effectively, they are very agile so they can strike a large area, and they are well armored even if they don't look like it. The are covered in armor, skeletons will have a hard time injuring them. An ankylosaur will also work. [](https://i.stack.imgur.com/MOifF.jpg) Of course if you want effective and fun, you can use go the monster truck route, the fuel efficiency is about the same as tank but one person can drive it, and many run off alcohol so they may even be able to get local fuel. Plus you get to have your character giggling like a lunatics while tearing around the army crushing skeletons under giant tires. [Answer] A demolition crane would give you the relative safety of not engaging the skeletons in close combat and the tool to crush many bones in one simple move. [](https://i.stack.imgur.com/TwlQ2.jpg) The disadvantage is than the crane cannot move very fast (although it's not very slow either), so she needs help against big groups. * Swiping the cranes head in an arc closely above ground can be used to knock enemies down * Helpers with pitchforks, nets or [Tim B's proposed foam guns](https://worldbuilding.stackexchange.com/a/136086/53228) can keep the enemies away from the crane while it crushes one after the other in quick succession. --- ## Pros * No ammunition or supplies needed during a fight * destroys bones and armor alike * attacks quickly and efficient * several meters reach and not stationary * Protected against arrows and other weapons * Can be utilized for different attacks like throwing boulders at enemies as well ## Cons * Helpers needed to fight larger groups (or you risk being overrun) * Not very agile on the battlefield * Vocal communication difficult because of the loud machine [Answer] If (like the question suggests) the protagonist understands enough about A.I. and robotics, I would conjure up some terminators (T800; the liquid metal of the T1000 and such is most likely something the protagonist does *not* understand, mostly because I doubt it is possible). Terminators are robust enough to take a beating and more than strong enough to pull two bones apart (no need to break the bones; a single bone cannot do anything on its own, it needs to be joined to another to actually do things) even without weapons. Arm them with melee weapons and the terminators become even more destructive. As for putting the terminators to work, they can go into buildings to clear them, run around the fields to attack large groups of skeletons, basically anything a human can - just much better. And if defeated, you know they'll be back. Added advantage: once the skeletons are taken care of, the protagonist won't have to explain where she got that strange magic device she used to take care of the enemy, because she simply got help from an army from across the mountains (or sea, or whatever you want). Sure they look a bit strange, but they look human *enough* not to cause suspicion in the aftermath. Unconjure them (or keep a few and rule the lands) and you're done. [Answer] Aerosol Bomb Just spray a wide area with very small drops of burnable fluid, like fog, and ignite it. The shockwave will seperate every single bone. [Answer] # Sound Warfare There is an interesting [article](https://www.popsci.com/technology/article/2012-11/acoustic-weapons-book-excerpt#page-2) with a lot of numbers about resonant frequency and disrupting human bones and tissues. I'm just going to snag the important parts here: > > [snip]... A dry (i.e., removed from the body and on a table) human skull has prominent acoustic resonances at about 9 and 12kHz, slightly lesser ones at 14 and 17kHz, and even smaller ones at 32 and 38kHz ...[snip] > > > And a fringe benefit is that: > > [snip]... In fact, when a living human head was substituted for a dry skull in the same study, the 12kHz resonance peak was 70 dB lower, with the strongest resonance now at about 200Hz, and even that was 30 dB lower than the highest resonance of the dry skull. ...[snip] > > > Which should mean that you're less likely to accidentally kill fleshies when trying to attack skeletons. The magnitudes of sound that are needed to pull this off are fairly high and require a lot of energy, but as far as an interesting mid-future approach, I think it fits the bill [Answer] **You don't need weapons, you just need a jail.** If they're animated bones, they aren't very smart. Trap a bunch of them in a pit they can't climb out of (even on top of each other) or dig out of. You can line and cover the pit with metal bars if desired. Or lure bunches of them into a building (or a large room) they can't dismantle or get out of. Built of stone (or concrete if available), no windows. A door of iron or at least some bars that will hold them long enough to brick them in. Make sure any cage or door of iron bars doesn't allow enough room for the skeletons to dismantle an arm or leg and send it through. You can also build chutes or walls that you might imagine could be used to herd cattle. They can herd the skeletons into their traps. Once they're all (or mostly) contained, you can come up with creative ways to destroy them. You can even experiment to find the best methods since, if it doesn't work, you'll only have one group to recapture. Fire, acid, crushing, all the ideas given in other answers. [Answer] Vats of acid? Flail tanks? Tsar Bomba? We are 8 people hiding out in a chicken farm! Where are we going to get all that? How about garage tech? I propose bowfishing arrows [](https://i.stack.imgur.com/RnpWm.jpg) made out of XL sized Molly bolts. [](https://i.stack.imgur.com/lYTyM.jpg) Here is the thing about skeletons. You don't want to bust them up. An animated skeleton is like a bag of dung. You don't like it, but you like it better in the bag. You don't want a bunch of loose skeleton parts scuttling about, working their way into your clothes when you are trying to make dinner. Keep all of them in the skeleton. 1: Molly bolt arrows are on a cord. 2: Shoot Molly bolt arrow at skeleton. Aim for ribs. 3: Molly bolt closes on the way thru and opens on the far side. Skeleton is now on a cord. 4: Your helper pulls on the cord. The cord is pretty long. It goes up and over something high before coming back to your arrow. Skeleton is pulled sideways to collection point. 5: Hoist skeleton off its feet. It will wiggle. 6: Tie down rope. Repeat. Alternatively, attach cord to arrows using eye bolts. Many arrows will be on the same rope. Many skeletons will wind up on one cord. It will be more convenient to move them around this way. Plus they will get tangled in each other when at close proximity. You now have a collection of skeletons hanging from something. You could store them in a shed in case you need them later (idea taken from Walking Dead). You could lower them into a hole and set them on fire. You could whack them like piñatas. Or all three! [Answer] ### Large, dense, heavy object summoned above them. A thick sheet or boulder of lead might work. For pinpoint accuracy, orbital satellite lasers should do the job nicely. [Answer] First lay down industrial strength vermin adhesive paper around the perimeter in a barrier meters wide to stop the crawling bone fragments. Then set up layer after layer of [claymore mines](https://en.wikipedia.org/wiki/M18_Claymore_mine) covering each side of your perimeter. [](https://i.stack.imgur.com/hzKk2.png) Then set up four Ontos vehicles armed with 6 106mm recoilless rifles each, loaded with beehive rounds. [The Ontos](https://en.wikipedia.org/wiki/M50_Ontos) [](https://i.stack.imgur.com/FOGUl.png) Then have snow shovels and acid barrels to dissolve any skeleton fragments that get through. Then play [this song](https://www.youtube.com/watch?v=S0OUvQnJYkc) and have your villagers chant, "Let's whip it baby, let's whip it right, Let's whip it baby, whip it all night." while they reload the Ontoses, set up more claymores, and shovel skeleton fragments into the acid barrels. Simplicity at it's best, right?? [Answer] For large scale destruction using bombs would be effective but it wouldn't completely destroy any skeletons they hit so i would suggest attempting to capture them and then either powder-rising them with a car compactor, something of that ilk or chucking them into an incinerator therefor completely destroying them which is what you want to do. for smaller spaces like a town... create a small ramming device that can be held that transmits a force into a target it is in contact with pulverising it. other than that, high velocity spinning blades that pulverise anything they touch, or just break it it don't mater, the objective is to destroy not injure until dead like a human. [Answer] Modern problem and solution: APCs tow a trailer with **a vat full of acid**. Wearing power armor (no one exits any vehicle without it), units go inside buildings to extract these skeletons and toss 'em in the tank. (in a comment, these skeletons are willing to self-destruct and can reanimate at will with w/e parts, so this isn't an option) Historic problem and solution: If they ever get a hold of you, you're done; they can basically pull a Neo (from *The Matrix*): sliver themselves inside you and blow you apart from the inside out. So the only solution is to keep them at bay as best you can. Ideally **inside a building that you can then bring down on top of them**, serving as final resting place unless you go digging. See, *Army of Darkness* (they couldn't reanimate) and Chernobyl (encased in concrete). [Answer] If you have the time to train civilians, to clear buildings you could start teaching them Ancient Roman ways of fighting: Tetsudo. Slow, but very effective against arrow fire. You can 'easilly' create the equipment, compared to 'tanks' and other methods. [](https://i.stack.imgur.com/sWs5s.jpg) Once the enemy has spend all their arrows, you could send in your reserve forces, as these legionaries / auxilliaries are most likely spend, during their first fight. I'd go with something like this: [](https://i.stack.imgur.com/rsojU.jpg) But I'd replace all the units with regular soldiers, with warhammers, and atleast some kind of a checkboard formation, keeping your most experienced soldiers in reserve. Perhaps even train cavalry, and equip them with light armour & a morning star. It'll be enough to shatter skulls. I'd keep your magic in reserve, and if it the story allows it'd create scrolls of healing, or scrolls of protection to protect / heal your units. Perhaps an last ditch effort, incase stuff goes south, some kind of protected car? [Answer] For 1 on 1 or freeing houses from undead vermin: Step 1: aquire first simple weapon to be on the safe side. I'd use some sort of mace or baton. Step 2: gas mask Step 3: throwable bladder with bone dissolving fluids Step 4: computer core with simple but maybe learning Ai. It has to have a multilayered armor of overlapping metal, so it won't get destroyed by medieval means Step 5: add the core to a little mountain of synthetic muscle fiber. If you bind three together, they can be controlled to curl in every directing desired. It might need little cores along the way to regulate the contractions according to will. Step 6: combine the muscles with the core and attach nerves and a battery, so it can move. Add sensors and maybe a mechanism to clean the chemicals and possibly use some exergonic energy for movement Step 7: cover it with some sort of shock absorbing and chemical stable jelly. Step 8: insert bladder and start programming. The outcome should be something like a slimy springy glob of goo. A synthetic muscle slime golem. It could roll and reach narrow places. By steering the outer ends of the fibers to be soft, it would make very little sound, when rolling or falling. If you let the fibers contract, it should be easily able to lodge in small crevices on walls. There should be no problems with stealth and infiltration. When it engages a skeleton, it can stop incoming blunt weapons by absorbing the force. Slash and pierce damage could be minimised by wedging blades and arrows between the coated fibers. It Could attack by jumping on the target then covering it completely and mashing it with the dissolvent. It could be used as exoskeleton, too. [Answer] I notice that nobody has latched unto this sentence: > > This includes weapons and tools that could semi-realistically be built with modern technology even if in practice the expense/complexity would be unfeasible. > > > Why settle for realistic things when you can use modern weapons/tools as an inspiration to make something new and ludicrously effective? Since: > > I'm most interested in the situation where the protagonist is forced into a situation of needing to dispatch enemies that have occupied the building she is in. > > > Then let's see... how about something like a swarm of chainsaws mounted on a mobile rack with the protagonist in the center? It's impossible to get close without being thoroughly disintegrated. If protection against arrows is needed, add an armored cabin in the center. Since it's not required for our protagonist to *actually* understand in great details the inner workings of such a device, she can imagine it as being infinitely powered by unobtanium, thus eliminating fuel problem. The whole device can be ~~made~~ imagined small enough to traverse buildings. [Answer] Bludgeoning weapons and basically any high-powered explosives. Sledgehammers should be pretty good at breaking the bones, and enough TNT can reduce skeletons to piles of white powder in seconds. [Answer] creating a vehicle similar to that of a steam roller or bulldozer might be an effective way of breaking bones quickly and and with little reminisce ]

[Question] [ I'm thinking of a world that values freedom but rates intelligence and logic so much that it dominates the entire society. Pupils take tests during school and this is averaged out and then given a value. Various SCI-FI cultures are based on logic (Vulcan for one example) This voting system would be proportional representation, but when you vote you vote with your IQ, thus everyone has a vote but it is weighted by their IQ. I.e. someone with an IQ of 140 would get 140 votes. someone with an IQ of 70 would get 70 votes and so on. Therefore the intellectual has more weight in a vote, but only an edge. Real high level of IQ become inaccurate so let's assume that it's capped at 150 and the bottom is capped at 50. What would be the possible issues of this voting system? [Answer] The most obvious issue applies to all weighted voting systems, whoever gets to define the tests has power to influence the vote. Say everyone on the IQ evaluation board is of a particular political persuasion or have the same opinion on a political topic. This bias could subtly (or overtly) be introduced into the IQ testing, giving higher IQ rating to people with similar political opinions and lower IQ ratings to those who disagree. This means that when it is time to vote the people with certain opinions would automatically have an edge with their higher IQ ratings. In addition to the possibility of bias from those preparing and administering the tests, there are additional problems. As mentioned in PipperChip's comments even if the tests were able to accurately measure general intelligence, high IQ would not guarantee that the person has any knowledge of the facts or experience with the issues involved in the various items being put to a vote. General intelligence would not make your uniformed opinion more valid than a well experienced expert with a below average IQ. Those with subject matter expertise and advanced degrees often feel it makes them qualified to offer opinions outside their area of expertise, this does nothing to stop them from frequently being wrong. Additionally many legal and voting issues are based on value judgments and opinions which don't fall into a simple right/wrong dichotomy and are not affected so much by the intelligence or knowledge of the individuals voting, but by those individual's different desires for a society. [Answer] The problem is what IQ actually measures. My father was a collector of IQ tests, and I (and my sisters) took well over a dozen before graduating high school. And we reviewed them, and learned the 'trick' of the patterns to recognize, and we did better -- all of us -- with practice. It is a lie that your IQ cannot be increased; take an IQ test every week and understand why your misses *were* misses, and you will find the same **type** of questions on subsequent tests. I was personally doing 20 points better on such tests, just between sixth grade and twelfth. I do have natural talent (and went on to earn five college degrees including my PhD), but the fact remains training can improve scores. As an expert taker of IQ tests, I can also tell you they don't measure anything you care about in **politics**. IQ tests are generally about puzzle solving, and who gives a crap? I am far more concerned, in politics, with whether people are selfish or cooperative, with how much they understand and accept how much of their lot is due to dumb luck (even the dumb luck of the genetic lottery, being born with natural talent, intelligence, looks or wealth that others were not lucky enough to get -- or vice versa, being born without natural assets, or disabilities, or into poverty, that others **were** lucky enough to avoid). You don't have to be as adept at puzzles, math, science and *general understanding* as I am in order to get my vote, or I wouldn't be able to vote! What I want in a politician is somebody that cares about other people and can navigate political issues to do what I think is truly important: Minimize pain and suffering, prevent others from profiting by creating more misery, and balance our civic duties with our private interests, roughly 50/50. Much like the Norwegian mix of socialism and capitalism. If you want a scale; use a sociopathy scale [like this one](https://www.sociopathicstyle.com/psychopathic-traits/), employ lie detection methods if needed, and exclude from politics anybody that scores in the top third, or even top half. The problem isn't stupid voters, the problem is criminal politicians, sociopathic frauds that promise to fix the problems of voters when their only ambition is self-enrichment. [Answer] If you're giving everyone exactly as many votes as their IQ - the effect on the actual vote doesn't appear to be very much at all. See the below table for a population of 100 million to illustrate - the vote share for IQ 120 + is slightly higher than with a normal democracy, but the fact there are exponentially fewer people in these higher intelligence brackets means that the linear multiplier on their vote weight has less and less of an effect. See below for a rough idea of the vote share for each IQ demograph, split out by ranges of 10 IQ points. [](https://i.stack.imgur.com/3LwzC.png) (IQ is maxed out at 150 here according to your specification - you can see though that even if it wasn't, the over-150s wouldn't make much of a difference at all) (additional info removed - I double checked and I made a mistake) [Answer] **This has been attempted in the US as a form of voter surpression by proxy**. Actual examples of the test are available online ([one example from Louisiana is here](http://www.openculture.com/2014/07/literacy-test-louisiana-used-to-suppress-the-black-vote.html)). As you can see from the sample below, it is actually a typical IQ test of "puzzles". [](https://i.stack.imgur.com/6O8v9.png) Failing one answer meant failing the test. You had only 10 minutes to complete all 30 questions, and the first several minutes would be wasted attempting to make sense of intentionally serpentine sentences. In many cases there was no correct answer, or instructions may be interpreted several ways thus allowing the tester to arbitrarily declare the answer to be wrong. The test of course was never intended to actually discern literacy. **It was just a pretext for voter suppression**. People who were assumed to be "educated" (code for white) would not have been asked to take it. The test was a proxy pretext used to suppress African American votes during the Civil Rights era. The law claimed to serve a noble purpose that many people would agree with (literacy), while in practice served a gatekeeping agenda that many of the same people would *not* openly agree with (racism) but were happy to accept the outcome anyway. In the end, any system that works to remove voters from a democracy is a form of voter suppression and problematic. [A recent SCOTUS decision](https://electionlawblog.org/?p=92675) has stated that gerrymandering by political party looks exactly like voter suppression by race. Each could be a proxy for the other. If I have to explain it: **someone is trying to game the system to their advantage**. There are no noble reasons to try to prevent part of your population from voting. They can't win unless they suppress votes. [Answer] * Cheating on IQ tests. Like faking sickness, but for intelligence... * Candidates focusing on smart people to get more votes * Adding to tension between smart/not-so-smart people * Thus, putting oil on the fire about the intelligence debate * High IQ candidates would be more likely to win, perhaps at the expense of high EQ or more grounded candidates Let's not forget that there way more normal IQ people than high IQ people. So, we would have some kind of smart elite, against the 'normal' majority. But the main issue with this system would probably be the **perceived injustice**. In fact you would need 10 persons with 130 IQ against 13 persons with 100 IQ, so the advantage isn't that huge. But people would perceive an injustice independently of its proportion, when, given their number, they would far exceed the voting power of high IQs. Then a *anti-IQ candidate* would show up, obviously win, and abolish it. Then high IQs would just end up despised, I guess... Oh, and my answer should get the most votes people, my estimated IQ is 134 ! (just kidding please don't hit me) :p [Answer] Your problems are as follows 1. All tests are [biased](http://www1.appstate.edu/~bacharachvr/test%20bias.pdf) 2. All tests [can be gamed](http://www.slate.com/articles/news_and_politics/explainer/2011/10/increasing_your_iq.html) 3. IQ [changes](https://www.livescience.com/36143-iq-change-time.html) over the course of one's life, especially in childhood and adolescences (where most testing would tend to occur.) 4. IQ is influenced by [nutrition](https://en.wikipedia.org/wiki/Impact_of_health_on_intelligence), [education](https://www.voanews.com/a/study-more-education-increases-iq-score-136593433/169492.html), [chemical exposure](http://www.environmentalhealthnews.org/ehs/newscience/iq-effects-childhood-lead-exposure-persist-in-adults/) and [drugs](https://www.forbes.com/sites/travisbradberry/2015/02/10/new-study-shows-smoking-pot-permanently-lowers-iq/#386681202f5b). This means one group could suppress the voting power of another group by physical means. An additional bonus is that by suppressing the other group's intelligence, the power-group blunts any competition. 5. [Smart people](https://www.forbes.com/sites/christinecomaford/2017/03/11/why-smart-people-make-stupid-decisions/#7f150d5f5405) can make really dumb decisions. Groupthink, echo chambers, confirmation bias and the like are all common plagues of smart people. 6. There is no system that can't be manipulated by a motivated actor with resources. Political power is a highly-addictive drug for which junkies will spend their life pursuing. [Answer] There are a wide variety of issues with IQ-based voting systems. First of all, **there's absolutely no basis to think that IQ based voting system would in some way be superior**, even if it worked as designed/intended, for a variety of reasons. 1. In practice, there's plenty of high-IQ people who hold awful political ideas. Tons of high-IQ people supported (pick your own awfulness from the list based on your political biases): Lenin, Mao, Hitler, Carter, Bush, Trump, Obama, Bin Laden, ISIS, Ghengis Khan, Holy Inquisition, human sacrifice, slavery, genocide, socialism, eugenics, nazism, etc... High-IQ people developed and supported the concept of using nuclear weapons, the concept of preemptive nuclear strike and the concept of MAD. 2. If you go beyond subjective politics and try to find explanation for the above, you find an interesting and disturbing point. The more intelligent someone is, the **better** they are at [motivated reasoning](https://en.wikipedia.org/wiki/Motivated_reasoning) (which is an endlessly fascinating field of study, which mostly can be summed up as "people are gonna believe what they wanna believe and there's little that can be done to change their mind") See [this study for the 'higher IQ' evidence](http://psycnet.apa.org/psycinfo/1991-97717-005). Or, to quote From Daniel Kahan's study "[Ideology, motivated reasoning, and cognitive reflection](http://journal.sjdm.org/13/13313/jdm13313.html)": > > On the contrary, **subjects who scored highest in cognitive reflection were the most likely to display ideologically motivated cognition**. > > > For more details on motivated reasoning, I would recommend a recent series of episodes on "[You're not so smart](https://youarenotsosmart.com/podcast/)" podcast. 3. People with high IQ are not guaranteed to be experts at picking political leaders. So, in representative democracy (instead of direct issue voting) IQ is not that relevant. Even assuming the (wholly incorrect, as per previous point) assumption that somehow, high IQ can lead to "correct" positions being taken by voters, that doesn't translate into picking "correct" politicians. Obama hoodwinked a whole lotta progressives (including high-IQ ones) into thinking he'll establish their utopia (as well as whole lotta conservatives afraid of the same). Instead, from him, they got TPP, Wall Street bailouts, support for Hillary over Bernie in 2016, wars in Afghanistan, Lybia and Syria; drone bombings; NSA ubiquitous spying; and more illegal deportations than under Bush. Trump hoodwinked whole lotta voters that he'll build the wall, deport tons of illegal aliens (he deported less than Obama did), drain the swamp, move the Israeli embassy to Jerusalem, repeal Obamacare, etc... So far most of the promises he made didn't pan out for his voters. I won't even go into high-IQ support for genocidal psychopaths listed in bullet #1 above. 4. Issues that require resolving are frequently beyond understanding of any single person, even with 110 or 140 IQ; unless they spend their life studying them. Having high IQ doesn't mean you know jack U&\*t about economics (as many high-IQ marxists prove). What makes you think non-economist with high IQ would be good at voting for the right people/issues when it comes to economics? --- Second, as other answers noted, **IQ may not be a very good measurement at all**. 1. Typical IQ "g" test measures pattern matching and sometimes problem solving. It doesn't measure emotional/social IQ (required to correctly understand politics, which in large measure is just psychology and social interactions). 2. There are many and varied criticisms of IQ testing in general, [covered in this Wikipedia article](https://en.wikipedia.org/wiki/Intelligence_quotient#Criticism_of_IQ) [Answer] So, in your scenario, all people are *not* created equal (under the law), all people do *not* have the same civil rights. Your statement that "real high" IQ is inaccurate is sad. *ALL* IQ measurements are inaccurate. For instance, one study showed that African-Americans taking a standardized test dropped (on average) by 10 points when the top of the form asked for both name and race compared to forms only asking for name. You simply can *not* create a single test to test the IQ of people who are in different families, traditions, cultures, of different ages and interests, and who speak different languages. How often do you test for IQ? All adults (all voters) once a year? Cheating will be pervasive. Corruption endemic. Finally, if the government values a person with an IQ of 120 more than one with an IQ of 119, then shouldn't an employer be able to use IQ to determine salary (and even whether or not a person gets hired (or fired))? Why not? Anyway, the basic notion of a democracy is the "social contract" in which we, the people, agree to abide by the results of the majority vote (in most cases), as any *other* method of public decision making is *unfair*. How is a system which requires 40% of the vote to determine 100% of the result fair? [Answer] ## Rebellion A very likely issue of high-IQ (smarties) having more authority than low-IQ (dumbies), is that the dumbies would be very against the system. People have a fairly solid idea of how they are financially, but even so a lot of poorer people would like to take down the "1%" People do *not* have a solid idea of their intellect, most people think they are smarter than average. To be told that you are in the bottom 20%, that your contribution is not very significant, would be either depressing or enraging. A similar idea is covered in the book Windsinger, where your job, house—everything is determined by your score in annual exams. It ends up in a huge class gap between smarties and dumbies, which breeds all the hatred, contempt, etc. [Answer] It may potentially exaggerate socioeconomic stratification, as the wealthy who have access to more education would get a greater portion of the vote. This may lead to policies which increase the wealth gap. This is dependent on what the education system is like in the country you are creating however. equal access to education would reduce this issue But for that matter the difference in [IQ is not that extreme](https://en.wikipedia.org/wiki/IQ_classification). [Answer] I have observed that IQ has effectively no correlation with candidate or party voting. I will explain the reason by analogy: About 10 years ago there was a study of Windows users that found no correlation between IQ and use of IE or Firefox as a web browser. A couple of months later a deep analysis study was ran and found a strong correlation between accuracy of risk assessment and use of Firefox. It turns out IQ isn't what you want to measure and what you want to measure is patently unfit for political measurement. A few cut-off-the-lower-end measurements work but not much else. [Answer] When you disenfranchise a section of the population you remove any incentive the government might have to provide them with services, support, or even basic justice. If you live in a democracy and write to your representative then you can expect to have your concerns taken seriously. If a lot of people write in about the same topic then they can actually shift policy. But if you are one of the disenfranchised then your concerns don't count. If you get treated badly by the government bureaucracy then nobody is going to come to your aid. So you will get a situation where, in any conflict between a voter and a non-voter the voter always wins: for instance the police and judiciary will accept a voters word over non-voters. If there is a planning conflict its the voter who gets to build his house where he wants. When hospitals and schools are being funded, guess where the money goes. And so on. Of course your proposed discrimination on IQ points doesn't totally disenfranchise the low-IQ, it just reduces their electoral clout. So the result is a toned-down version of the same thing. This creates an underclass who are getting the short end of the stick and know it, but they can't do anything about it within the system. This leads to crimes of poverty, frustration and hopelessness. Then riots. Then revolution and/or civil war depending on how things play out. [Answer] Due to the rules of question protection, user J doe at ~50 rep is unable to answer. He pointed this out in [chat](http://chat.stackexchange.com/transcript/message/38046927#38046927) and gave me permission to re-post his answer onto the question. > > IQ follows a gaussian distribution, such that: > > > [](https://i.stack.imgur.com/vKLoo.png)  > > With μ being the mean, σ the standard deviation and x the IQ. In your > case x is defined in the range [50:150], and we will take μ as 100 > (average for the American population) and SD=15 which is standard for > Stanford–Binet test or Wechsler. If you plot this function it should > look like this: > > > [](https://i.stack.imgur.com/m3EbI.png) > > This way you can estimate that there is ~2,5% of the population with > IQ=100 and if you want to know the IQ for the range [90:100] you can > integrate the function from 90 to 100 and you will get ~25% of the > population falling under this range. > > > If we use your voting system as IQ = voting points, your system will > therefore return ~2500 points for IQ=100 over a population 1000 > individuals and if we now use a specific range like [90:100] it > becomes interesting: you get ~25000 points. If you compare with the > range [120:150], which is larger (in terms of ranged values) and > describes the “smartest” individuals, you only get ~14056 points (I > did the calculation for you). Essentially because, as @danl pointed > out there is less and less smarter people as you group (and count) > them depending on their IQ. > > > Therefore you can conclude that for > example in a bipartisan IQ-based point system, although based on an > elitist mechanism (the smarter the more points you get), this system > would be actually (and counterintuitively) very democratic, or > Aristotelian if you will: to the “normal” people, the power. Note, > however, that if a large enough part of the “less smart” and a large > enough part of the “smartest” could regroup their votes, they would > outweigh the “normal” people votes… (range [50:90] and [110:150] vs > [90:110]…) > > > This gets into math that my makes feeble imagination brain-box smell like burnt toast, so if you have any question, ring @JDoe [Answer] All the problems already mentioned by other people plus: Intelligent does not equal smart. I know several 140+ people who have a lot of trouble operating in the real world. If you took them off campus where they live, they would not be able to survive. They would be making decisions based on theoretical optimums that would be less and less relevant over time. Now, if you were able to create an unbiased test that tested decision making over puzzle solving, you might have something. However, good luck on it being unbiased, who is going to decide which decisions are the best ones? [Answer] **You would have some protestors complaining about the test being racist, classist and/or sexist.** Perhaps a lot of people would accept the system, especially if it's been in place for a long time, but not everyone would like it. It would not be easy to make a system like that truly fair. * Since people with low test scores tend to have different kind of jobs than people with high scores, then the electorate will be biased against some industries, and biased towards bosses rather than labourers. Some trade unions will campaign against it. * Some studies have shown that girls test better when there are no boys in the room, and African-Americans test better when there are no whites in the room. The testing system might be biased against people who have been made, psychologically, to feel inferior even if they really do have the mental capacity to do well in the test. * Communities with low scores will be given less school funding by politicians, and then the next generation there will have low scores because they went to bad schools. There will be bitter complaints about this, especially if it seems to correlate with the politicians' ethnic prejudices. * If there is a mathematical or spacial concept which is modelled differently​ in the grammar or idioms of one ethnic group, then using that concept in the test could introduce an ethnic bias. Possible in any test, but twice as bad if the questions are written in sentences. Examples: + One dialect uses double negatives to make a sentence extra negative, another dialect uses double negatives to form a positive. + One community thinks of the future as being ahead of you because that's where you're going, another thinks of the past as being in front of you because you can see the past and not the future. [Answer] I am not sure how current IQ test is created, but Wikipedia stated that [IQ](https://en.wikipedia.org/wiki/Intelligence_quotient) is the result of mental age score divided by real age. So the younger you are, the higher your IQ, even though your mental age is the same. So, in this world, the vote of the old people is worth less, and young people is more. Some may think this is a good thing, as they dislike the conservative tendency of old people. Personaly, I value the wisdom of the old, and doubt the impluse of the young. There are good reason that most politican are not young. Edit: JamesD mentions that new IQ test has normalized between age difference. That invalidates my answer. [Answer] Ok i would like to add a dimension to the overall discussion. Namely: ### How do you weight the IQ? See the iq test does not tell you how many more votes a smarter person should get. How do you decide this. As somebody noted givin people one vote per IQ wouldnt make much of a difference but giving a person 10 votes for each point above an IQ of 100 and 1 below 10 would. But by doing something like this you would soon figure out that you are just in fact having a voter suppression scheme. See you should recognize that: a) IQ is an arbitrary measure b) It has an arbitrary scale A person with an iq of 120 is nor 20% smarter than a person with 100 we dont even know what it means, not really. So if you could put human inteligence on some absolute scale with 0 being as intelligent as rock. You might find that indeed a normal person is within 1% or less of the smartest one. meaning that the variance is nonimportant. Or it could be huge. We do not know. So in the end your system would just be an arbitrary feature and as such no different from any other oppression sceme hunankind has come up with. [Answer] One issue with this system is that it eschews the whole purpose of democratic government. We do not vote to find the *best* leaders - this obviously doesn't happen. We vote to get a government which is acceptable to the majority of people - though admittedly, this also doesn't always happen. By discarding the one man, one vote principal you break the system. So your world's governments would likely be even more unpopular than ours. This applies when you weight votes by *any* measure. Because you're weighing by IQ, there would be a large subset of the population that is excluded not only from government but also from the economy. One would expect this group to be angry and rebellious, but unable to find a peaceful way to improve their lot. Assuming this system has been stable for generations, that would mean this group has been successfully subdued by the ruling intelligencia. Either the high IQs willfully make concessions to the low IQs, thus undermining the apparent purpose of the system, or there would be a subtle authoritarian element to your seemingly enlightened world, with dissent consistently suppressed. [Answer] Richer people usually get better educations, either because the parents pay for the child to go to a better school or because better schools exist in more affluent areas; thats the way things work in the UK at least. Thats not to say ever person who gets a high IQ comes from a rich background but on average more do because their brains are trained better. By giving more votes to people of higher IQs, your giving the rich more power than the poor (overall, there are obviously exceptions) which means that laws are more likely to favour the rich and parties that favour the rich will do better. Also, people with difficulties not may be represented well enough because they may have a lower IQ and so laws passed may not give these people the attention they need. [Answer] Intellect is qualitative and not quantitative. People with a high IQ can be autistic spectrum, and can read 100ds of books about social science and psychology, and yet be much less performant socially than people with normal IQ, i.e. aloof/rash. Instead of IQ people can be rated by hours worked that decade, charitable contribution, driving offences. in politics the most important thing is to stop career politics and mix politicians with ordinary workers, and to stop secrecy in all fields, secrecy in commerce, war, money, banks, lawmaking, secrets are the big challenge of governments, especially secret lobbying, influence, and secret influenced lawmaking. Also, politicians should be tested with current affairs questions like oral exam students on TV on a veranda for selection, for their knowledge, and not made to argue publicly for assesment as the only exam, and not hyped up by superparties that select the richest with pacts and syndicates. [Answer] I think the most crucial problem you'd encounter is that in a world with the characteristics of our current one, a person of average IQ is likely to try to settle issues with violence. A study at Stanford about 20 years ago showed an inverse correlation between intelligence, and the desire to be in management. (Sorry I don't have references; I don't remember where I saw the study, and don't remember enough about it to google it.) The impact of this is that our leaders have a below-average intelligence, and every organization that has open membership is rapidly devolved by incompetent, power-hungry leaders with no ability to comprehend the organization's original mission. Corporations rapidly become consumed by greed, political institutions are overwhelmed by power plays, and religions...well. Thus, in order to implement such a plan, you'd need a group of forceful rebels, or a huge media campaign...and you must consider that the media as it stands now, is effectively corrupted by what pays the bills. Alternatively--and probably the only viable solution--you could create your own society in isolation: Under the ice in Antarctica, in outer space, perhaps under the sea or underground. In any case, you'd have to HIDE this society from the mainstream, or it will be attacked on multiple fronts. Most likely, if it wasn't nuked, it would be overwhelmed from within by stupid people, planted there by clever organizations who take advantage of your desire to be helpful. It is a challenge that it takes a long time to express an intelligent thought, and a sad fact that few people have the patience to hear you out. You would need "stupid" people to run your military, if you did not escape current society, and that would be a HUGE weak spot. Of course, I have more thoughts on this :) but I think that's enough to chew on for now. [Answer] Intelligence is just one of traits (even if we disregard the issues with measuring it correctly). For one, psychopaths and sociopaths may be very intelligent, but you don't want them running the society, do you? So in ordinary democracy there also other factors besides raw self-interest that decide the outcome, for example empathy, which prevents us from building the efficient society that would gas the disabled and kill you secretly when do you are due to retire. This is just one of the examples why this is a bad idea. I am sure few more could be easily found. [Answer] Intelligent people can be brainwashed and mindcontrolled as easily as the less intelligent. They can also be bribed as easily. If we equate higher intelligence with higher education, they would probably be more indoctrinated and brainwashed by education. In a society of the kind you describe, those who control the educational system would also control the government. The political focus would probably be to suppress alternative world views that threatens the one taught in educational systems. It is reasonable to assume that higher intelligence equates to higher income. That might lead to conflicts and tensions if those with lower incomes do not see their needs being met. On the other hand, it all depends on the political indoctrination of those with higher IQ:s. Einstein for example was a marxist. As some people have noted, the voting system would probably need to be more skewed at the benefit of the intelligent ones to have any noticeable effect. [Answer] The main issue with this is that IQ is a poor predictor of success in the real world, and provides no measure of motivation, understanding of risk or social skills, andis also in many ways simply a measure of wealth and privilege. Form the link below, "It has been found that those in the mid to low achievement spectrum of Ivy League schools did not turn out to be world leaders — despite their SAT scores being higher than even the best students at the so-so colleges, who fared better." <http://www.huffingtonpost.co.uk/dan-goleman/iq-doesnt-predict-success_b_5658898.html> [Answer] Intelligence does not imply political skill or high character. US presidents tend to hover in the IQ range of 110-130, above average, a 'dumb genius'. What most of them have is the knowledge and political skills to get things done, something that pure intelligence doesn't convey. Remember Spock's remark in The Wrath of Khan: 'He is very intelligent, but his thinking is two dimensional.' Some of the brightest people I know were my college professors. However, their observations on political affairs were usually in the category of 'hopelessly naive'. A system that regards some people to be more equal than others can have only one logical outcome. Revolution. ]

[Question] [ An alien robot comes to Earth and determines that part of his plan here involves geting set up with a lot of cash in as short a time span as possible. He has a number of physical and mental attributes exceeding that of the average human to assist him with this; namely: * As a non-fleshbag, he does not feel pain, bleed, need to eat, and so on. He does need a certain amount of oxygen, although very little, and "sleeps" in roughly human-like cycles to recharge. * He is more or less indestructible and will quickly heal from most wounds, excluding severe bodily trauma (e.g. losing a limb). * He has peak-human strength and speed, and superhuman reflexes. His senses of sight, sound, and smell are also superhuman, but not to the degree that they would no longer be grounded in reality. * His robotic brain functions on a level basically equal to that of a supercomputer; he has a perfect memory and is able to instantly process even highly complex information. This also allows him to read and learn very quickly, as he only needs to so much as look at a page in a book to fully understand it. * As one would expect from these capacities, he has educated himself extensively on humans and human culture. He can be assumed to have memorized all of our publicly-accessible history and possesses an encyclopedic knowledge of the world. * This also extends to knowledge of psychology, making him a very skilled people person. He has no supernatural powers of persuasion, but having memorized everything we have to offer about how our brains work brings him pretty close. He looks and acts perfectly human, and would only risk discovery by allowing somebody to observe his inorganic functions (such as his lack of blood). He would prefer to keep a low profile and especially avoid government scrutiny, so anything overtly illegal is a bad idea. He is a more than capable fighter thanks to having memorized vast quantities of relevant information, on top of his physical capabilities. However, he would prefer to avoid having to kill or fight very many people, due to the attention that kind of thing tends to bring. I imagine that his best bet in accomplishing this would be putting his supercomputer mind to use in some kind of large-scale financial maneuvering, but I'm not really sure what specifically he'd be able to do. Any input would be much appreciated. Edited for extra details: He can choose where he ends up on Earth, but it likely doesn't matter too much. Even if he's not able to procure transportation, he can really just walk or swim to wherever he needs to go. He doesn't have a legal identity, on account of not being born on Earth, but probably wouldn't struggle too much with obtaining one by going through the standard processes as a John Doe or immigrant. To expound on his self-imposed restrictions, he is not significantly opposed to illegal or arguably immoral means. However, as a general rule of thumb, any legal method is better than an illegal equivalent, and possibly better than even an otherwise superior illegal equivalent. This is for no other reason than to minimize attention; if he was completely certain nobody would ever realize the crime had been committed, then it wouldn't matter, but that's rarely a safe bet to make. He doesn't have a real problem with screwing people over or even killing them/otherwise bringing about their demise, but this is generally to be avoided for similar reasons. Also, all things considered equal, it's better not to eliminate potential future resources, even if there isn't an immediately useful connection in place. [Answer] # He could start a ~~cult~~ religion With a near-perfect understanding of human psychology, he should have no trouble convincing people to give him their money. With careful maneuvering and timing, he could build up his organization to have significant economic and legal clout, protecting it from authorities that might try to shut it down. In addition, he has the ability to demonstrate miraculous capabilities, further bolstering the faith of his followers in his superior nature. If he had sufficient advanced technology, he could even cure disease or injury to secure the loyalty of his followers. In the end though, his strongest asset would be immunity to the human tendency toward megalomania, thus allowing him to carefully develop his base of power without losing it to hubris. If he's sufficiently benevolent, he might even use his developed power to eventually free his people from the slavery into which they had placed themselves, with newfound knowledge and abilities; really it depends on what his long-term goals are. [Answer] # Freelance Design/Development/Translation/Law/Ect With superhuman intelligence and speed, the robot could juggle dozens of freelance contracts simultaneously and complete in a single day jobs that would normally take weeks. He could crawl freelancer contracting sites like a spider and automatically apply for jobs. He might need fake credentials to get the first few jobs, but he'll quickly gain reputation as the guy who always does perfect work. If he wants to conceal the fact that he is a single agent who can work impossibly fast, he could open his own freelancing or contracting company. This company would state or imply that it has lots of contractor employees or freelancer users (or possibly both). In the case of a freelancing website, most of the accounts would actually belong to the robot. To avoid being *too* unethical, the robot would charge competitive flat rates for jobs rather than an hourly rate. This way, he could finish a large project in an hour, then wait a week before turning it in. The nice thing about this is that all he needs is an internet connection. This solution can be paired any other answer that would leave the robot with some down time. [Answer] # **Identity Theft** Okay, this answer is pretty crazy, but hear me out. Our superhuman, perfect memory robot should **take advantage of someone who already has a lot of wealth.** Our robot just has to kidnap/kill (murder?) a current billionare. Preferably young, as that gives him the most amount of "years" to be that person. In terms of actually stealing the identity, I assume he knows how to impersonate people well and make disguises (given that we don't know the "biological" make-up of our robot, I wont assume much more). As long as there isn't some biological password (and depends. Our robot could "borrow" the unfortunate's victim's eye or hand or etc. etc.) to this person's wealth, our robot will eventually figure out how to bypass the various security measures protecting the wealth. To hide the fact that he isn't actually Mr. (or Ms.) Net-Worth-Billions, it would be best to choose someone who isn't a large personality with the media and has relatively no obligations/connections. No living nuclear family would be ideal. And if the robot wants, he could make this figure drop off the face of the earth (within a few years, with our robot's capabilities), and as the years go by change identities to legitimate people after his fake identity "dies", willing his fortune to his new self, of course. A quick google search provides a [good list here](http://www.ndtv.com/photos/news/forbes-10-youngest-billionaires-9348#photo-120267). (though I kept my research to a minimum. I feel as if searching "single young billionaires" is a little weird...) To further increase his fortune, do what the other answers have suggested: invest in stock, gamble, etc. NOTE: This idea came to my head before reading James's answer, but it follows the idea of using someone who already has a great deal of wealth. [Answer] The fastest way to make money for a robot with a supercomputer brain will be to hack the systems of the companies involved in running tax havens. These companies are intended to make money disappear from the taxation jurisdictions where it was originally earned. Once it has enough control of those finance systems the robot can make the money disappear into accounts of its own. It will have set up those accounts in advance. Sensibly this money will be banked in as many parts of the planet as possible. For a little color and excitement the robot could infiltrate drug rings and work its way up the criminal hierarchy. Then simply steal some of the large amounts of cash that drug dealers have a bad habit of leaving lying around. (Yep that's absolutely true too.) If the robot could gain access to the Mister Big's of any drug rings it should be easy for it to either blackmail them or hack their bank accounts to make off with their ill-gotten gains. [Answer] I think such a robot would scrounge up some pocket change (say 100 loaves of bread worth of local currency) in a trivial amount of time by noticing local opportunities within the first day or so of watching human behavioral patterns. At this point, I think he'll buy a prepaid credit card and go straight to the best form of gambling online. With superior parallel processing, substantial winnings across multiple sites funneling into multiple discreet accounts will rack up finances quickly. With a tidy sum in tow, the robot may now move to a more advantageous location. I think he'll start working with stocks, currency trade and the global market, as in Bellerephon's answer, however I don't see a passive role. While being discreet is a goal, the robot will have a good grasp of its own abilities and how much confidence to have. With enough finances, covert identities beyond our tracking should be a breeze. Due to this I think such a bot will stimulate up and down turns in the market toward his advantage until he's got enough money to create a sustained system for whatever it needs money to do. [Answer] Professional gaming would be the career I would choose for that robot. With super-human reflexes, memory and processing capability, he would quickly become one of the top players. Winning in high paying tournaments would net in quite a good amount of cash. He could do olympics but medical checks would reveal his identity. [Answer] His best totally legal low key way is to buy stocks and shares and investments. With a supercomputer he would be able to predict crashes and booms with some accuracy. Furthermore he could be checking his investments permanently where their he is so he will be able to go out and do stuff at the same time. The only negative is if he is too successful he may be noticed. A slow option would be to get a well paid job. Doctor, Company manager etc. Not having to buy anything will obviously speed his money making but it will still take many years. Possibly the quickest legal way is too sell blueprints for alien technology. If he doesn't want to speed human technology growth too much he can sell old/outdated tech which will still be an advancement to humans. He would have to find an anonymous way to sell them but he should manage. His quickest overall way is to hack into banks or, if he is more moral, large crime groups. He could take their money and keep it. He has a supercomputer brain so should be able to cover his tracks. [Answer] A lot of the answers here seem to be making 1 of 2 mistakes. # Mistake 1: Aiming too low Being a doctor, doing a large number of freelance projects, becoming a professional gamer etc. These are all great ways to make tens of millions of dollars, but lousy ways to make billions of dollars. Given the robot's abilities, our aim should be to make billions of dollars, and I think that's certainly a realistic goal. # Mistake 2: Assuming that the robot can do something magical Examples: Hacking accounts and draining them of billions of dollars, murdering and assuming the identity of a billionaire, starting a cult and brainwashing people into giving you billions of dollars. Read the question again - the robot's abilities are idealized forms of abilities that already exist in today's world. Supercomputer-like-processing power? Supercomputers already exist. Extremely good people skills? Genius level IQ? Perfect athletic abilities? People already exist with each of the above qualities. If it's so easy for someone with those abilities/skillsets to start a cult or make billions of dollars through hacking, they would have already done it by now. --- The way to approach this problem, is by asking ourselves what the richest humans in the world have done, in order to amass vast sums of money, and then have the robot pursue similar strategies. Given that the richest humans have already amassed $10-100B in personal fortunes, this strategy will attain results on par with, or exceeding, previously suggested answers. And given that these are real success stories that we are emulating, that means that our strategy is going to be much more realistic and practical. --- # Option A: Finance/Trading Some of the richest people in the world got there through finance. Warren Buffet, worth 60 billion dollars is the prime example. George Soros, Carl Icahn, Ray Dalio, each worth US$10-20B, are other great successes. Strategy: Use superhuman intelligence to put together a perfect GMAT score and great MBA application. Attend a top school like Wharton/Harvard. Use the resulting connections and prestige to get a job at a successful Hedge Fund. Use your super-intelligence to deliver great ideas, analyses, and above-average returns. Use your salesmanship to make your above-average returns, sound like an extremely impressive accomplishment. Use your political skills and collection of accomplishments, to get promoted to top positions at the Hedge Fund. Using that ledge, build a reputation for yourself, as one of the best investment minds in the industry. Eventually, either take over the top job at the Hedge Fund, or start a new fund of your own. Use your above average returns, and great people-skills, to attract massive amounts of capital. Make obscene amounts of money off the 2-and-20 model that Hedge Funds use for fees. Upside: 1. You can make $10-60B, over the course of 10-20 years 2. You only have to beat the market by a small amount, on a consistent basis 3. Pretty reliable and realistic strategy Downside: 1. If you happen to get an unlucky streak, your investment record will be ruined by mediocre returns, and you'll have a hard time escaping that # Option B: Entrepreneurship With a few finance exceptions, the richest people in the world are all entrepreneurs. Bill Gates, worth 80 billion dollars, is a prime example. Carlos Slim, Jeff Bezos and Mark Zuckerberg, each worth US$40-60B, are all great examples as well. Strategy: Identify a solvable market need, or a rapidly growing market. Use your intelligence and engineering skills, to build a great prototype. Use your prototype, along with your networking and people skills, to hire the best talent as early-stage employees, and secure VC funding. Use the capital and hired talent, to improve upon your prototype, make it even better, and attract more customers. Repeat the above, another 2-3 times. Once your startup has grown into a medium-sized company, becomes its CEO and shift your focus towards management. Use your people skills to win lucrative contracts. Use your political skills to sabotage your competitors, or to rig the marketplace in your favor. Use your strategic and leadership skills, to shepherd your company into becoming the next Microsoft/Google/Apple. As a significant shareholder of a rapidly growing company, you can easily make tens of billions of dollars for yourself in the process. Upside: 1. Tremendous amount of money to be made. US$40-80B has been made by numerous successful founders. 2. Relatively short time horizon: 10 years is sufficient to make tens of billions of dollars Downside: 1. "Identifying a solvable market need" or "picking a rapidly growing market" is very hard to do. You can easily find yourself in a dead-end market, or one that has already been won by entrenched incumbents. 2. Most startups fail due to marketing reasons, not technical reasons. Even if you have a fantastic prototype, you may still fail to build user traction. Tremendous luck involved in building user traction. *"Being in the right place at the right time"* # Option C: Corporate Management Join a extremely profitable company, at the entry level. Use your intelligence to deliver great work output. Use your political and networking skills to win promotions consistently. After ~10 promotions, you'll end up as the CEO of the company. Continue to deliver strong results, and earn lots of money for yourself in the process. Upside: 1. Extremely reliable. There isn't too much luck involved at any step. If your work is good enough, and you're good enough at charming people and playing politics, you're pretty much guaranteed to get promotions. 2. In terms of power, the CEO of large companies have a tremendous amount of power. This power could be an end-goal in itself, or used as leverage to make more money in other ways. Downside: 1. You'll make peanuts, compared to options A and B. Jack Welch, the most famous and successful CEO in American History, is not even a billionaire. Realistically, given the robot's abilities, you'll make close to a billion, and if you're really good, maybe a couple billion. It's a far cry from what you can make in the earlier options. 2. It'll take you a really long time. Assuming 10 levels between entry-level-positions and the CEO, and 2 years per promotion, it'll take you at least 20 years to work your way up to CEO. And then another 5-10 years to make some "real money". --- Overall, if the objective is to make the most amount of money with the least amount of risk, option A is likely your best bet. Option B is the way to go if you feel really confident, and want a high-risk-high-reward option. And option C is the way to go if you want a low-risk-guaranteed-results option. The combination of these 3 options should beat any other ideas suggested here thus far. [Answer] # Personal Assistant to the Wealthy He could approach one of the richest individuals on the planet and **prove himself to be a superhuman alien robot**. Then offer to be that individual's secret personal assistant and advisor on all things for a very large fee. I'm not sure if this idea fits your requirement regarding low profile... > > He would prefer to keep a low profile and especially avoid government > scrutiny... > > > [Answer] Build and licence processor chip designs. ARM just sold for 32 billion, without ever selling CPUs to consumers. They build reference designs and sell them. Don't destroy current technology; gradually grow to a dominant position in the market. Keep demand high by pushing new processor designs incrementally. NVIDIA, ARM, and AMD all use this business model. As the verge says, information is king! <http://www.theverge.com/2016/7/18/12211484/arm-holdings-softbank-acquisition-intellectual-property-patents-value> Another user suggested selling newer technology would water down his own advantage; this is true to a point, but if he is advanced enough he could simply beat our own technology long enough to make a fortune and stop before he becomes threatened. If he could drive his competition into the ground, he could delay technology in the long run. *EDIT: Really Quick Money* Rather than sell new plans legitimately, he could sell current designs and technologies to shady buyers like North Korea, Iran and unscrupulous copycats willing to knock of the major chip designs. [Answer] ## Fastest or Fastest Ethical? The quickest off the bat would be crime. Stealing bitcoin would be an easy beginning with his skills. **Why doesn't anyone do this?** [They do](https://en.wikipedia.org/wiki/Mt._Gox) Follow this with leveraged manipulation of financial markets and a large fortune is there to be made in fairly short order. **Why doesn't anyone do this?** It's well known that it's possible, but it's [illegal everywhere](https://en.wikipedia.org/wiki/Market_manipulation). Doing it and not being caught, that's the game. The key to our robot doing this is that he can run the high speed trading in a considered manner rather than just using a script that reacts in a pre-programmed way. Since he's a robot he has the advantage of replaceable kneecaps for when the organised crime syndicates catch up with him. Then he can relax into a fabulous lifestyle of high stakes poker. **Why doesn't anyone do this?** They do, but most people aren't good enough. Poker is a game against other people, you have to be better at reading them than they are at reading you. Who can read the poker face of a robot? [Answer] Can't believe anyone has mentioned the gambling root here. A roulette wheel is pretty quickly memorized, and a super computer would have little issues calculating the speed of the ball vs the speed of the wheel and at least narrow down the part of the wheel the ball will land in well enough to skew odds heavily in its favor. Start with a low bet ($1 or so), win a couple times and increase the betting until the desired amount is achieved. Not an unlimited well as casino's will monitor, but it'll work to grow a decent nest egg. Extra points if he can jump on a craps table and find a method to throw the dice in its favor as well. If it's inclined to less morale methods, slight of hand techniques can be used to pick money off gambling tables or exchange cards at a blackjack table as well. Comes with the risk of being caught though. [Answer] For a relatively quick turnaround on some amounts of money, you could look towards outstanding academic bounties for answers to specific "unsolvable" things. These problems humans can't yet solve may have been solved already. The downside to this is the possibility of these requiring a (potentially lengthy) peer review process. He could also sell pieces of his processing software to complete some objectives we're on the way to already like self-driving cars and things. Patenting or trademarking some processes and then selling the rights to use them to various large corporations could net him a nearly eternal revenue stream legally + without doing anything. One such item might be whatever process he uses to determine what things are. We've been trying to teach computers to recognize objects in pictures ever since computers were invented, if he could establish those algorithms and sell licenses, he might never need more money. Similarly, processes for material creation/manipulation, new metallic alloys or non-metallic compounds, new storage media for data (especially non-volatile methods), his entire body is made up of things that our scientific community would foam at the mouth just thinking about. And again, patenting these things and then charging for their use would provide a long-term income stream. Once he has money he could also potentially purchase things we consider waste materials that he's able to re-process into usable materials, patent a process using them and then resell the materials to others (using one or more shell companies so that it isn't blatantly obvious what he did there). The patents (conveniently) don't require any ongoing effort from him other than cashing checks, leaving his time free for whatever. They might also provide plot hooks if people start trying to steal them, use them improperly or turn them into weapons. [Answer] # He could print the money Being a supersmart AI engineered by a technologically superior alien civilization, he could simply build a sophisticated money printing machine. Using his superior technological knowledge, it would not at all be a problem for him to fake the petty security features on humanity's modern bank notes. Given his vast knowledge of human psychology, the robot could also take over a central bank such as the Federal Reserve by economic and political manipulation. He would then have access to the human money printing infrastructure. [Answer] How about... # Telemarketing/scams You know that Nigerian prince that keeps asking you to help him transfer his $8,000,000 inheritance? Those emails still float around because there's at least a couple of people who fall for it. Now imagine this Nigerian prince upgraded his grammar, and was the most intuitive and socially gifted person on the planet. Able to laugh and cry, and understand you like no one ever has. Oh and only one body? For a super computer? First goal is to produce multiple bodies/robots/voice+phone extensions, so he can make 100,000 calls and emails simultaneously. Computer processors don't need to "focus" like we do, they are amazing at parallel processing. # More ethical version Now he's set up with a call station where he plugs into 10,000 phones, he puts out an online education website. One-on-one tutoring with the world expert in the field you want to study. Patient enough for a 5-year-old (at 20USD per hour), intelligent enough to coach Elon Musk through his next invention (at 2,000USD per hour, + 8% shares in the company). Anyone in the world with any amount of money would invest in this top education system. Then we go beyond academic help. Maybe there's a million/billionaire who is suicidally depressed. Mr. Smooth gets him back on his feet, ready to take on the world once again. What value does this rich man put on his life? Maybe that motivation is worth 200million to him (because he'd be dead otherwise). This version takes a bit of time to set up a repertoire (and you need quick money to buy all the phone lines, etc). So maybe a combination of the two, and if he wants to be nice, the ones he scammed get a free year's subscription to his tutoring. **Edit—Anonymity** Being a common household name in the Education industry isn't "minimizing attention", but I suggest he could do something similar to [IceFrog](https://en.wikipedia.org/wiki/IceFrog). Still known everywhere, but known *for* being anonymous. [Answer] # Black Widow / Trophy Wife If it can perfectly do about anything the best of us can do in any field and it has the looks, this robot should have no problem being the perfect spouse for a billionaire. It should hook up, marry and kill an old billionaire and inherit millions. The only problematic is the kill part, but it shouldn't be a problem, with superior knowledge of toxicology. But if the robot is good enough with the law and acting its part, it could also marry and divorce and get half the assets in court :-) [Answer] # Enter the movie business My suggestion would be for him to found a company. Probably an entertainment company as that's big business. The robot being able to understand every pop culture reference by reading thousands of webpages, posts, and comments at a time could be a fantastic writer in modern culture. He could also watch and process many sources of video at once, multiple tv channels and youtube videos. Our robot friend could easily create scripts for movies and tv shows that are algorithmically guaranteed to succeed based on the mass amounts of data he is able to process. The robot would probably have to publish under a pen name, or claim that a staff or team of writers created them. Because of the amazing social skills the robot would be able to gain very quickly, getting started with just a script for a block buster movie or two wouldn't be difficult. With the money from that the robot could produce their own movies and begin to form relationships with people in show business, with the goal being to eventually start his own company to rival that of twentieth century fox and disney. As an added bonus if he lived a private life, that just makes him more of a fixation in society. He could then market his own brands and get paid huge amounts to appear on tv or be interviewed by journalists. Not to mention the amount of power he would wield over the populace. Someone already mentioned a religion, but isn't pop culture just religion in a different form? We have weird and arbitrary rules we that we follow and people get ridiculed or idolized for breaking, we have customs that are observed surrounding important events, and it provides a system where some people are arbitrarily lifted above the rest of society. But I digress. If the robot then used his influence to get people to donate to charities he had a hand in or was an administrator to, there would be loads of money to be had there as well. [Answer] [The same way that robots make money in our own world nowadays.](http://www.youtube.com/watch?v=g8huXkSaL7o) With the difference that being sentient, this one does not need a human tayloring and retayloring it with ever new stories to fool the gullible. The nigerian elite trying to hide money overseas gets old really fast, you know. Set up multiple accounts on tax havens, send the bait and wait. Easy peasy. The robot could also make money on pyramid schemes, or for a more honest living on the internet, by running [arbitrage](https://en.wikipedia.org/wiki/Arbitrage) - say, between Ali Baba and Ebay, for example. Buy cheap junk on one, sell it for 10x its price on the other. Also adware. The robot, being a robot, could set up a million pages full of junk and ads. By gaming with [SEO](https://en.wikipedia.org/wiki/Search_engine_optimization), the robot could get enough clicks to make a living. Last but not least, it probably comes from a place with far superior technology than ours. The robot could use technology we can't even dream of nowadays to crack bitcoin (cue in to some specialists claiming how this would take more computing power than what is feasible), or to release a search engine better than Google and Bing and compete with them, for example. [Answer] An advanced alien with excellent understanding of human psychology and culture should have some good ideas about what startling revolutionary concepts humanity is ready for "next". Invent it. Your alien is definitely one of Steve Jobs, Mark Zuckerberg, or Satoshi Nakamoto, but I don't know which. If Steve Jobs, he already made enough money to get home. For that matter, he could be one of the first two *and* Satoshi. The cunning thing about Bitcoin is that it helps avoid scrutiny: it's very hard to be all three of rich, unknown, and legal, so an alien who wants to be all three in the modern world might have to invent a crypto-currency even if he didn't plan to cheat at it. By getting in early and designing the algorithm to your own exotic super-computer-based abilities (and perhaps even based on some advanced knowledge of a break in the crypto primitives involved?) you could rapidly build a fortune so large that the limiting factor is how you convert it to other assets without making it obvious they're all ultimately being paid to the same person. [Answer] # Arbitrage on Jewelry With superhuman appraisal abilities, he could recognize under priced jewelry in Shenzhen, then use his swimming ability to cross the harbor to Hong Kong, then use his knowledge of human psychology to sell the jewelry at a premium. [Answer] **Mine Bitcoin** Use it's supercomputer brain to score bitcoin to get some basic investment capital. **Develop Apps** Adapt a popular game/divertesment from it's own world and sell it, using the money from Bitcoins to finance. Alternatively, there are probably several "obvious in hindsight" apps it could develop and sell based on Apps and Utilities available in it's homeworld. Think *A Connecticut Yankee in King Arthur's Court*. [Answer] With this robot's abilities it seems to me the easiest way to rack up tons of cash quickly is to become a bounty hunter. He could probably quickly locate, capture, and deliver Ayman Al-Zawahiri who has a [$25 million bounty in his head](https://www.fbi.gov/wanted/wanted_terrorists/ayman-al-zawahiri) alone. Alternatively he could work for insurance companies recovering high priced insured stolen goods. Regardless if he is hunting people, treasure, or a mix of both the robot could capture several high value targets around the globe quickly. The bounty hunting proceeds would then become his seed money for the real wealth generators. Next he leverages this cash to bootstrap big real estate deals, tech startups, or whatever else his superior intellect deems to be the best investment vehicle. Once these investments take off he launches a SpaceX competitor to cover the creation of his launch vehicle. [Answer] # PayPal fraud Use known (or unknown, if you're keen) security vulnerabilities in web software to harvest usernames and passwords and a botnet. This gives you access to a lot of careless payment accounts up front, no further effort needed. You probably want to throttle and distribute your activity so that you don't alarm PayPal so much that they lock down all payments or something – your botnet helps here a little. Laundering the ill-gotten gains is probably the hard part: maybe you don't even have a bank account, and have to resort to something like buying gold or drugs or other physical value stores online, and arranging for them to be delivered to a sketchy alley or somewhere you can pick them up without having to own the postal address. There's also a bunch more analogous cybercrime, e.g. ransomware, which seems similarly suited to your abilities. One thing that I think has been assumed in other answers but not given in the question is the ability to interface directly with the Internet or other computer systems. That would make the above strategy (and many others) hugely more scalable, but you'd maybe need some creativity to build the input/output devices that would actually enable you to do it. Then I imagine a lot of your early profits would go into upgrading your hardware and network connection, so that you could keep scaling up. [Answer] Best advantages : * Knowledge of alien technology * Super computer brain Worst disadvantages: * Lack of bank account, ID documents etc * Lack of seed funds The hardest part for your robot is the begining. With no legal identity he really can't enter into any legal high paying venture. With no seed money he cant even gamble or purchase fake ID, internet access etc. Step one : Seed money * High risk : use superior physical abilities to steal money * Low reward : manual labour, odd jobs, cash in hand work Step two : First 100k * Medium Risk : Black jack. With his super computer brain he can count cards and consistently win at black jack. Also perfect play at poker should beat most human players. * Low reward : Bitcoin mining. once he can afford an internet connection that super computer brain can be directly used to create bitcoins. Difficult to convert to real money though. Step three : Buy fake identity With a legal ID and bank account your hero is now able to work bigger schemes. * High Risk : attract venture capital with alien tech. This has to be the easiest option. You dont even have to sell the product. Just have some impresive prototypes. Maybe have human pastys to front the companies * High Risk : illegal fiancial products like a ponzi scheme Low Risk/Reward : ??? [Answer] ## Security Bounties Analyze software systems for security risks and report them for huge cash bonuses. He could likely report tons of them in a day, which would be way faster than a slow build up of religion. Then, he can work for private software companies or start his own security firm. [Microsoft pays out big time for security bounties](https://technet.microsoft.com/en-us/library/dn425036.aspx), as does [Apple](https://www.wired.com/2015/11/hackers-claim-million-dollar-bounty-for-ios-attack/), [Facebook, Google, Mozilla](https://bounty.github.com/). Your robot could bring in hundreds of thousand of dollars, or even millions, in a single day. Probably while walking down the street. Since "He would prefer to keep a low profile and especially avoid government scrutiny, so anything overtly illegal is a bad idea." I'm suggesting the legal avenues of security bounties, since this is less likely to result in him being investigated. [Answer] Why do he need to work, he can transfer virtual money as every thing is in digital format. He can hack and create account and enter any amount of money in that. Once he is in the database. He can have several accounts and lots of money into them in different banks so that no one can catch his illegality. He can perform all above task mentioned by readers. He can replace all big things with his better versions. Something better than google, better than microsoft or apple. [Answer] A quick way to make small amounts of money fast would be to be a street performer, like for example, a juggler or a magician, making money with his superhuman abilities. If he makes some money he can show some of it to passers by and use it to bet that he can do something that few or no humans can do. I once read something about dropping a dollar bill a specific distance and being able to catch it out of the air after it had gained sped by falling that distance was humanly impossible. Whatever the precise details, the robot could make some money by betting that he could do it and those he bet against couldn't. The robot could select a human who looked rather fast and athletic (like in the 75th percentile in speed) and bet him that he could run a specific distance faster than the human. The robot would probably only have to run as fast as a human in the 80th or 85th percentile to barely beat the human and win the bet. If the robot could quickly and easily change its appearance it wouldn't matter if sometimes cameras caught it committing crimes. Thus it could quickly break into cars, jump start them, and sell them to chop shops. It could quickly break into houses in unexpected places that wouldn't have alarms, and steal valuable goods (but only stuff that could survive the process of getting out of the houses) to fence. Thus the robot might quickly make a small amount of money by petty crime. So if the robot quickly makes a small amount of money by various means, it would have enough to get a cheap fake idea, and possibly get 2 low paying jobs on different shifts. Then it might fairly quickly amass enough money to get a much better fake identity, pay for patenting inventions, invest in something with a very high return, etc. So those are some ideas how the robot could start from nothing. But why start from nothing? If the robot has selected Earth and studied Earth for some time before landing, why doesn't it bring counterfeit money, synthetic jewels, gold bars, prototypes of slight improvements over Earth technology, and other wealth with it? If the robot does that it can skip the early stages and perhaps go straight to a big money making plan. [Answer] **Become an advisor to the rich and powerful.** Being a master of human nature, he'd have no problem charming himself past security and staffers, and getting personal meetings with politicians, businessmen, CEOs, national leaders, etc. Once there, he'd break the ice with advice so astonishingly clear they wouldn't even question where he came from, and he'd consult them on an ongoing basis. He'd be the "quiet little secret" of the powerful across the globe, and would be paid very handsomely for it. Low profile, friends in the right places, and potential to make a lot of money in a short period. Works? [Answer] With a perfect memory and superhuman reflexes, he should be able to make big bucks quickly as a rock star. Then get active with investments and day trading after getting a big pool of money. [Answer] Bodysnatching is an excellent plan, but offing a billionaire is thinking too small. What about the head of the most powerful, isolated organization in the world? No, not the POTUS. The director of the NSA. With direct access to an organization that already is completely opaque, and servants able and willing to commit crime and atrocities for the 'greater good', and an instinct for engendering fanatical loyalty, and access to yet further, as yet underutilized, supercomputers, citizen databases, and globe-spanning botnets, now running alien code and duplicates of his personality and... Well, you get the idea. Money would be no issue, nor would anything else. As for avoiding attention, well, there's not really a better place to work. ]

[Question] [ So a [declaration of war](https://en.wikipedia.org/wiki/Declaration_of_war) is made when you wanna go to war with someone else (duh). For example, country A hates country B's guts. A declares war on B. A and B go to war. One side wins, unless the whole world gets embroiled in it, then things get way more complicated. So why not skip the declaration? Country A hates country B's guts. A carries out a sudden invasion. B is probably dead. Is there a reason to declare war during a time period before modern history? **(Outside of ethical reasons and things like a knight's honor)** It seemed to me that declaring war against another country you wish to invade is just a really stupid thing to do. It's like telling someone that you want to murder that you are gonna shoot them (thus giving them time to run or fight back). Of course there might be a few problems, B:"Why are you amassing your army beside our border? You dare go to war with us?" A:"Nope, we definitely not going to war with you, we would have declared war if we wanted to." The element of surprise would definitely be lost if the enemy finds a large encampment of soldiers outside their border but if it was planned well, it could be a devastating invasion where B was unable to mobilize their soldiers well. This is also assuming that there were no international laws that prohibits both the threat and the use of force in international conflicts, which have made declarations of war largely obsolete in international relations in the modern era. [Answer] * A declaration of war allows the recipient to surrender before interrupting both economies to form armies for invasion and defense. * A declaration of war establishes basis for closing borders, ceasing trade with the recipient, and expelling opposing citizens. It provides legal penalties for those who continue such trade or harbor such citizens. (I.e., the bureaucracy can handle violators rather than requiring the sovereign to hear and act.) * A declaration of war announces to third parties that a very dangerous situation is approaching and they may wish to leave either or both countries for the duration. * A (-n ideal) declaration of war will specify conditions under which hostility will cease. (See [casus belli](https://en.wikipedia.org/wiki/Casus_belli).) Again, perhaps the recipient will acquiesce without further hostilities. Such a declaration has the benefit of appearing to be a demand from an aggrieved party for redress rather than being an irrational attack by a lunatic. Neighbors who talk before attacking are much better neighbors than irrationally dangerous neighbors. * It announces an opportunity for third parties to join or oppose the declaration in force, aid, or word. In any case, you find out who your friends and who your not-so-friendlies are. [Answer] A declaration of war would be needed to raise troops. Before the modern era, there weren't standing armies in most countries. You had to pull labor off of crops/cattle and make them an army specifically for a war. And if a king didn't have his own resources directly, he'd have to levy troops from vassals. All that takes time, and you need your allies to know the enemy to help persuade them to fight. Moreover, a surprise attack with an army is damned hard to do anyway -- armies move slow compared to messengers on horse. Surprise attacks are for units, not armies. It can be done, but (my opinion) the improbability of success probably makes the advantages of the declaration of war worth the loss of surprise. [Answer] Right now you're paying attention only to A and B. Declaring war is typically in large part about countries C through Z. If countries C through Z see A's attack on B as reasonably justified, they're likely to sit back and let A and B fight things out on their own. If, however, A is seen as excessively aggressive, and attacking B simply because it can get away with it, that poses a substantial threat to the security of all the other countries--if they let A take over B, A is likely to remain aggressive *and* after a few years of assimilating B's economy is likely to be considerably larger and more powerful as well. Unless C through Z feel insulated from A's aggression (e.g., even A + B is still too puny to be a threat, or A and B are too isolated to threaten others) they're likely to consider A making a sneak attack on B a good reason to join the fight--and even if A is extremely powerful, the combination of *everybody* else is likely overwhelming. Keep in mind as well that even if C through Z are relatively pacifistic, there's likely to be at least some "hawkish" element in each that would welcome an excuse to invade A and get access to its resources. As such, even if A's attack on B leads to little *real* concern, it's still entirely possible that others will use it as an excuse to invade A anyway. Bottom line: "international laws of war" (or anything similar) are largely a codification of preexisting behavior. Unless A and B are the sole powers in existence, the basic forces that have led to passage of those laws will be at work, and push toward (at least roughly) similar behaviors. [Answer] (Typing on my phone here, will elaborate more using a computer at a later time) Yes you do get an advantage, but at the cost of being branded as a person using dubious means. Back then im guessing the norm was to declare war, thus doing a sneak attack will raise eyebrows of neighbouring countries. This will not only lower their opinion of you potentially causing your country to get ostracized from trade and agreements, but it might even incite a joint attack by other countries against yours. Another potential impact is the respect and faith of your country citizens, similar to the vietnam war incident America faced, choices made by a nation that is not in favour with its citizens can lead to internal conflict. This puts a real damper on the overall war effort. [Answer] * A properly declared state of war could trigger certain constitutional and legal provisions in country A. Reserve troops can be mobilized. The media can be censored. Troublemakers can be held without trial. * Troops from country A might have better chances of being treated as POWs if they are captured, especially if there was a low-level "dirty war" between A and B before and both sides got used to shooting spies. * As Drake mentioned, often the declaration of war had the form of an ultimatum. This could be done for propaganda only or genuinely in good faith. *"Stop mobilizing* your *troops or* we *will go to war, too."* [Answer] Launching a surprise invasion is almost completely impossible. More so the closer you get to the modern era. People tend to notice when large armies gather, or pick up on communications signals. Villagers flee to get out of the path of the army, they warn others. The message just keeps going. Eventually it reaches someone that can do something to confirm the rumors and respond. Thus, surprise is lost. All this can happen very quickly, but you can not gather an army quickly, and even with modern equipment you can't move an army all that quickly. The logistics just make it impossible. The 'declaration' isn't usually as simple as sending a message saying "We're at war". Usually it would likely boil down to nation A making demands of nation B, and being refused. After that, a military build up tends to make things pretty obvious. Additionally, as mentioned above, if you suddenly lash out without a clear justification, your own people will be very unlikely to support it. Which (Even in a feudal society) has very serious consequences on your efforts. [Answer] You need to seriously reconsider what war is about. The leaders of country A do not attack country B because as you say "Country A hates country B's guts." Instead Country A attacks country B because either: * Victory presents personal gain for the leaders of country A. * War itself leads to personal gain for the leaders of country A * Not starting a war leads to personal loss for the leaders of country A. War follows certain conventions, and breaking some of these conventions carries a risk of labeling you as a bad guy, which can reduce your prestige and it can also reduce popular support from the war, which threatens the leaders' power. For example, when the US recently attacked Iraq it's known that they did spend quite some effort to forge evidence of WMDs, to give them a just cause for starting the war. One reason they did so was so they wouldn't be labeled as warmongers, which would cost them prestige and popular support. Aside from prestige there's the equally important aspect of allies, and popular opinion about the war in neutral countries. Consider that leaders of other nations may want to join the war on either side but can't do so because public opinion is against them - if they joined the war anyway, they would lose a lot of prestige, just like Tony Blair did. By transmitting the image that your war is a just war, you make it easier for other leaders to join your side of the war and harder for other leaders to join the enemy side of the war, without them losing public support in their countries - which will directly threaten their power. In war, in every historical era, there are things that are considered bad form, such as: * Have sharpshooters focus on officers. * Kill prisoners. * Rape and pillage. * Use crossbows. * Eradicate a conquered city by slaughtering every living thing inside of it. * Attack hospitals. * Start wars without war declaration. * Do anything other than meet the enemy army in open field mass battles. You'll notice that not a single one of the above is universal, and each depends on where and when the war took place. If you look at history a little bit more, you'll also notice that there are examples where each of these were broken, during times when it was considered bad form to do so. This was done because the perceived benefits outweighed the perceived cost. Sometimes that perception was right, other times it was not. Consider the last time the Crimea changed hands - there was no war declaration, there wasn't even a war, yet soldiers invaded, took the country, and countless conventions were broken. Last but not least, as long as you pretend to follow the conventions, you can hope that the enemy also follows the conventions. When the convention was that peasants on the losing side are slaughtered and nobles are ransomed, as a noble it was a good thing for you if the enemy followed the latter part of that convention. [Answer] Honor was important in pre-modern society, certainly more so than now. Also, in societies with more absolute concentration of power, the ruler was synonymous with the country. Wars between countries could be more accurately seen as wars between kings in the pre-1500 world. If you are going to prove yourself better than this other king, you have to show up and fight him honorably. To do that, you can't stab him in the back, so a declaration of war is needed. Now the fights didn't really go honorably at all, what with all the pillaging and bribing nobles to switch sides, and murdering each other's peasants. But it was more important to maintain the fiction of honorable battle, and that was done by establishing a [causus belli](https://en.wikipedia.org/wiki/Casus_belli), at least in Europe. In other parts of the world, you see the same process, rulers would send notice that, "Hey, bro, I'm coming to take all your money and women, and then force you and everyone else in the world to acknowledge how powerful and awesome I am." [Answer] * **For bending the market**, a declaration of war most importantly allows traders and merchants to act on the base that there's a war. Also enemies may start to spend more resources on military and army and that may be harmful on the long run. * **For speculation**, instead of deliberately damaging a foreign market your declaration of war is mainly to allow you change prices and have a direct income from that. In example when your country has a lot of weapons industries a call to the arms is beneficial for your economy regardless if you will fight or not. * **For allowing civilians to retreat**, if you have a economic target (in example a iron mine), people may just to decide to stay away from it * **For selecting the place where to fight**, if you interested is in some economic resource you force enemy army to defend a particular spot regardless if you will invade it for really, that allows to make tactical Attacks elsewhere. * **For converting people to your religion**, feared people may want to just join you, however it is more likely you obtain also the opposite effect, it definitely depends on your culture. * **Because of political pressure**, you do not intend really to invade or attack someone, but maybe you want to obtain a particular result, the defending country may counter-attack for that reason, because if they give what attacker wants, no one forbis the attacker will ask the same again * **Symbolic act with consent of the other country**, there's again no real intention of war but both countries have interests in appearing as "in war status" to other people and countries (in example they both have an advantage in a reciprocal embargo). * **To turn off revolutions**, feared people may be more willing to stay with current leaders if a war is preparing, this has been showed many times even in recent times. However if the war last too long people may suddenly become more willing to start a revolt. (In that sense, a flash war is good) You cannot analyze a war if first you don't identify all parties that have an advantage from that. As you see there are reasons for which friends may be at war and enemies may be at peace. That what is weird about economics and most people just don't realize. After all rarely do nations leaders die, most times just civilians and soldiers die. War & economics are bad. Especially in a totally free market [Answer] Your assumption here is that countries just start a war because "they hate each others' guts", but that is usually not the case. Sure, there might be emotions and personal relations involved, but in the end, you usually want to achieve a goal by waging war. Depending on the era and other circumstances, this can go from raiding for resources to conquering land to showing strength and improving your political position. You usually do not want to go to war on your own, you want to achieve a goal and for that, you need to give your own people and your allies a justification, maybe even a motivation they can get behind. Also, even in a big war, you usually do not want to slaughter every last enemy citizen. In the long run, you want them to work for your economy, one way or the other. You do not want to give them too much reason to hate you and cause rebellions for decades. In most democracies, it will be frowned upon when the government just declares war spontaneously, and other forms of government might not be happy about it either. Breaking the rules also tends to deteriorate your relations with other states, even your allies, who now have to be suspicious what crazy plan you come up with in the future. Also, as others stated, it gives your enemy a chance to negotiate, especially when you appear stronger (which is usually the time you would chose to declare war) and have an opportunity to achieve your goals without actually fighting. A "surprise invasion" might actually make sense for a small country with a very mobile military, but for bigger countries, it's usually impossible to organize something like that. [Answer] Many countries, especially democracies, require both in law and social norms for a public debate to occur before going off to war. A ruling party or coalition government that hoodwinks the general population and sends its people to war without "selling" it to the general public first is not likely to survive re-election unless the war is a quick and resounding success. In addition, if the executive branch of government has the supreme authority of the armed forces, as in America, then troops can be sent on the president's whim. However, the legislature often controls the budget, and if the executive decides to declare war unilaterally, the legislature can slash the budget for the armed forces. This almost never happens, because it looks bad politically to cut funding for the military during wartime, but if the war is largely seen as illegitimate and unpopular by the general population, then the legislators who cut short the executive's military incursions would have much to gain by standing up to an act of tyranny (which they will use to characterize the executive's actions, if they have any propaganda sense whatsoever). This happens in autocracies/aristocracies as well, although it is much smaller in scope and less transparent. Even if the "supreme leader" has absolute authority, a dictator is only as strong as the people that keep them in power. Often these people are significant players in the military and the economy, but the process is largely the same: people who support a given administration will want to know that their resources will be used effectively in an upcoming war, and will be most displeased if they are not consulted beforehand. [Answer] There are two things to this question: * First, why to declare war at all * Second, why to declare war before attacking For instance, when Nazi Germany invaded the USSR in 1941, they declared war. But they did so about 4 hours after invasion started to provide for surprise attack. Why declare war at all? Usually you want your population to know that you are in war, and you want neutral parties to keep from supporting and trade with your enemy (you can warn them you would attack their ships), and you want your allies to join you. Why declare war before attacking? If you want either preserve your image internationally or you want to make an ultimatum. Ultimatum is the final demand which you present to your adversary that may avoid hostilities. Every war costs money and life and if you can get what you want without war, it is always better. A third question is whether to declare war verbally or legally. This mainly has to do with domestic policies. [Answer] The advantage of declaring war is that it lets your far flung allies gather support and kickstart their own efforts. These allies may have to convince their populations that this is a good idea (as implied in several answers here already), and may have to also make some rapid changes in their economies to cope with the demands of a war they might not have seen coming. An additional advantage to declaring war (again in terms of alliances) is the morale boost it can give. Have a look at the British Empire and Dominions at the start of the second world war (*edit: and France - with it's colonial resources. I left it out. My bad*): It wasn't just England declaring war on Germany, but Great Britain AND Australia AND Canada AND New Zealand AND the colonial administrations of India, Singapore, Kenya etc etc. Citizens of Britain in this case might not have felt alone in a fight with all the commonwealth and all of its resources lining up behind them. [Answer] **A country will formally declare war if some sort of rule exists requiring such a declaration and the leadership making the declaration does not wish to challenge the legitimacy of those rules at the start of this war**. The rule can be formal or informal. It can be a domestic rule or an international/transnational one. It can be from a secular or religious authority. It can be from a government or non-governmental organization. It can be as simple as the dominant great power simply dictating terms to its clients and vassals ("If you're going to go to war, we expect you to follow these rules.") The rule might exist for either offensive or defensive wars, or both. There are lots of reasons why such a rule MIGHT exist (some of which are mentioned above,) but ultimately it comes down to the fact that some rule DOES exist, and the leaders don't want to challenge it. [Answer] ***"A semblance of legitimacy"*** To many rulers with one eye on their place in history, a formal declaration rather than a sneak attack reflects better, and at the very least provides a 'semblance of legitimacy'. If things go wrong, you might be in a worse negotiating position, or rather, without one entirely, if it all began with a sneak attack. ]

[Question] [ Think of a more or less traditional medieval fantasy world: multiple races, magic, some alchemy/magitech that is of comparable power and reliability to ordinary magic. And in this world there exists the Loveland, where all the people are pacifists and do not accept violence towards other people for any reason (the question as to what constitutes "people" is outside the scope of this question, but they are fine with slaughtering cattle that they grew). Now, how could such people protect themselves and their land/property from being raided and taken into slavery by the next band of orcs passing through? Make following assumptions: * There is no Unobtainium in their possession that they can deny rest of the world if attacked. * The country survived for centuries, so this should be a reliable method not easily countered, not some sort of one-shot lovecraft surprise. * The technology/magic in their possesion is not significantly superiour to that of their neighbours, so any wall/barrier can be breached given sufficient time/resources. * The land is rich and bountiful, so others would take it if they could. * Amongst races of the world there are sentient undead, golems and elementals, immune to mental magic (and yes, they are considered "people" too for the sake of "no violence" rule). The most obvious choice would be to enlist protection of some sort of allies, but who will protect Loveland from those allies when they change their mind/ruler? Any sort of mind control can be noticed over sufficiently long time and will only foster enmity between allies. And this sort of violence by proxy has quite a limited distinction from ordinary warfare. **So, with the aforementioned assumptions, how could a pacifist country reliably protect itself from any threat, including betrayal by an ally? What about the case with an additional limitation of no violence by proxy allowed either?** [Answer] # Make raiding them prohibitively expensive A raid is only in part about finding a target that is weak enough that you can take what you want. The other part is about the idea that there is something to gain there, that is *worth more than the cost of going in and getting it.* Even if it's possible for other races to bring down walls that these creatures create, that doesn't mean it's cheap. If it takes month to bring down a wall, only to realize that a new one has been crafted behind it, at some point raiders will realize that they are wasting their time. Possible options include: * Physical intervention. Walls, mountains, ravines, raging rivers. All the things that make it really difficult to bring an army and really slow to progress. * Misdirection. Either magically or not. After three weeks of marching for the pacifist city, the enemy ends up... back home. * Supply disruption. Realizing after a week of besieging a city that all the incoming caravans consist only of carters complaining that all their food keeps getting stolen. Without food, sieges will have to be aborted. * Breaking morale. Disgruntled troops require a lot of resources to keep them from killing each other or deserting your forces. Targeted, hard sound at night to keep them from sleeping. Unleashing vermin on the camp. Spoiling the enemy's food. Breaking whatever entertainment gear they have brought. Eventually, people will go crazy. If you keep it up, at some point, the enemy will simply not *want* to keep wasting time and money on trying to get at you. It won't be worth it, no matter how much gold is promised, to be so miserable for so long, with nothing to show for it. [Answer] It's right there in the name: There's no need to fear invasion or retaliate with violence against any foolish enough to violate their sovereignty, because the inhabitants have weaponized ***love!*** Any self-respecting medieval fantasy kingdom is going to have forests all over. Well, *these* woods are filled with nymphs. Normally they're sweet, peaceful creatures dedicated to strengthening the forests and keeping the ecosystem healthy and in balance, but you do *not* want to threaten them or their home. They'll wander in to enemy camps and use their natural beauty, magic, and feminine wiles to seduce the troops, and especially the leaders, into a highly suggestible state that its victims call "true love" and many outside observers would call "mind control." No one truly knows what happens to those who succumb, but common reactions from soldiers who survive and manage to escape from Loveland include PTSD symptoms, a tendency to flinch when touched, despondency, heartbreak, alcoholism, and swearing off women forever. It should be noted that, as time marches on and non-traditional gender roles have begun to take root in some of Loveland's neighbors, certain obvious tactics to circumvent the influence of its nymphly guardians were attempted, followed immediately by the discovery, for the first time in known history, that male nymphs exist. The exact implications of this are still being pondered... [Answer] Remember the three means by which civilizations live or die: "Guns, Germs and Steel". Since you say the Lovelanders have given up weapons (no guns) and have no superior technology (no steel), I direct your attention to germs. The people of Loveland have developed an immunity or tolerance to some parasite or disease that is localized and endemic in their land. This disease is debilitating to most outsiders, possibly even fatal. Exactly how the Lovelanders developed this immunity but other people could not has to be hand-waved; you might make a concentrated exposure to this thing a rite of passage for native Lovelanders as well as any outsiders wishing to join (and not all of the native-borns survive it). Since most outsiders couldn't withstand even casual exposure, the Lovelanders are really under a de facto quarantine; they're perfectly happy to stay in their own lands, and nobody else ever goes there. ...Until your hero discovers he's not only immune but not even a carrier for the bug, which is very rare (bordering on a religious phenomenon), allowing him to come and go as he pleases, furthering the plot. [Answer] In real life (RLtm), this situation exists with various nonviolent religious sects seeking haven inside the United States. Like in RL, it would work over long periods of time if Loveland were embedded within another country that tolerated or encouraged its existence and was powerful enough to defend both. I know that this *slightly* violates your "no violence by proxy" statement. However, consider that the surrounding country would use violence only to defend itself. That vigorous defense would not be on behalf of Loveland. However, it would have the effect of protecting Loveland anyway. [Answer] Here are the first few ideas that popped into my head: 1. **Loveland is such a rich, bountiful country** that none of its squabbling neighbors are willing to let it fall into the hands of their rivals. Whenever one nation attempts to invade and occupy it, all of the other nations rally to drive them out. "I will be dead before I see Loveland in the hands of the Elves!" --Anonymous dwarf 2. **Loveland provides an essential service** to its neighbors, the continuation of which is considered vital to the stability of the world around it. One such service that comes to mind is banking-- maybe something along the lines of [the Iron Bank](http://gameofthrones.wikia.com/wiki/Iron_Bank_of_Braavos) in Game of Thrones. Loveland has proven to be an honest, reliable and impartial manager of the region's cash flow, and it is widely believed that anything more than a minor disruption to its daily operations could introduce a catastrophic amount of uncertainty into the neighboring economies. Other countries may contemplate a hostile takeover as a means of debt relief (for, nearly everyone has borrowed vast sums to fund their various conquests), but they aren't about to let any of their rivals get out of paying off *their* debts-- much less start collecting payments from everyone else. Thus, any attempt to invade would have the same result as described in scenario 1. 3. **Loveland has focused solely on defense** while the other nations have focused on developing strong offensive capabilities, or a balance of offense and defense. So, while the Lovelandians may not have catapults or fireball spells, their castle walls and magic force fields are always just good enough to shield them from the outside world. This may seem to contradict the OP's third bullet point, but I don't think it does. True, any wall can be breached if you put enough time and effort into it, but if you breach a Lovelandian wall, you'll probably just find another, even stronger wall behind it. They can keep bolstering their defenses for as long as you can keep trying to break them. 4. **Loveland *has*, in fact, been invaded**, but the invaders were so bewitched by the beauty and enlightenment of its culture that in the end *it* took over *them*. Instead of defeating or destroying the Lovelandians, they *became* them. (The saying "Rome conquered Greece, but Greece conquered Rome" comes to mind). 5. **Loveland has nothing to offer** that is of interest to anyone outside of Loveland. (I just realized that this does, in fact, contradict the bullet points in the OP, but I like it too much to remove it). Maybe it's a barren desert, smelly swamp, or other wretched environment that no one but a Lovelandian would even want to visit, much less own. The weather is unbearable, the scenery very unscenic, and the resources, if there are any, are worthless outside the country (maybe they crumble to dust due to some ancient curse or something). The Lovelandians adapted to this place long ago, but no one else has, or wants to. [Answer] Politics. They're surrounded by two countries who have treaties defining what their borders are, and other countries in the area who will intercede if one side violates the treaty. Then, make it so that there were several agreements between the two countries about what the borders were, with slightly different dividing lines. The agreements differ in two regions: Loveland and Moneyland. Each treaty gives one region to the first country and the other region to the second. Since neither region wants to give up Moneyland, they can't claim a legal right to Loveland without angering their neighbors, and provoking hostilities. Make Loveland be basically a city-state that existed before the conflict started, and both sides would likely leave it alone, while also being willing to step in and defend against other nations. Note that this doesn't conflict with the requirement that "the land is rich and bountiful." It can be as prosperous as you want, just as long as the other region is even more valuable. This sounds like a ridiculous and completely unsustainable situation, but there's an example of something very similar in the real world. [Bir Tawil](https://en.wikipedia.org/wiki/Bir_Tawil) is 800 square miles (2060 square kilometers) of unclaimed land between Egypt and Sudan, because neither wants to relinquish a claim on the Hala'ib Triangle. And the dispute has lasted over 100 years, proving that such a situation can last for extended periods of time. [Answer] Their land and they themselves are considered holy by the other peoples. So offending them is a sin that will bring your soul to the hell after death or damage your karma. Or they believe gods will revenge for them (see Iliad). Consider how religious societies, monasteries and theocracies survived on Earth. Alternatively they do science so that powerful neighbours respect and protect them because they bring insight into how the universe is functioning or provide astrology/oracle services. [Answer] There are actually a few [countries in the modern world with no military](https://en.wikipedia.org/wiki/List_of_countries_without_armed_forces). [](https://i.stack.imgur.com/MqgcM.png) They do seem to all share a few things in common. * They are all tiny in territorial (and probably population) terms. The only one I don't have to squint to see on a world map is Iceland. * They have relatively inaccessible territory. Almost all are islands. Of the ones that aren't, two are almost entirely jungle, and two more are tiny mountain countries. The sole exception here is Vatican City. * They are under the protection of larger neighbors or benefactors. You could claim Vatican City to be an exception here too, but you can't really get at it without sending your military through Italian territory (their capital, no less). Italy is of course a NATO ally, with their own military and under the protection of the US. So it looks like realistically a putative pacifist nation will be a relatively small country, perhaps too small to stand up to any serious attack anyway. It will be an island nation, or in some other kind of very difficult to maneuver terrain. And it will be somewhere a much larger nation that does have a good military considers within its sphere of influence. The combination of the difficultly in conquering them and the possible response from their allies makes them not worth the effort of invading. [Answer] Here's my suggestion: They are neutral, the banking country. All other countries trust Loveland, and store their money there. If a country then attacks Loveland, they lose their money. The aggressor then gets attacked by the other countries, who are defending their own interests. In order to prevent small raiding parties, the other countries send a detachment of soldiers to patrol the borders, and to hold the line against a full attack until reinforcements arrive. If needed, the backstory can have a country which attacked Loveland, and got promptly destroyed. This protects them from betrayal, but it might violate the "No violence by proxy" restriction. [Answer] **Their "defense weapons": fearlessness, contrariness, and bull-headed stubbornness** If the get invaded, they totally do not cooperate with the invader. They ignore them, do not cooperate, loudly declare the injustice, and are utterly unfazed by threats of, and acts of, violence against themselves and their families. Naturally, quite a few do get killed/tortured right off the bat, as the invader tries to impose their will. But what the heck do you do with a population that's immune to being intimidated, and is completely harmless against you even as you're hurting them? There's nothing you can do. Invasions require that the target population is, at some point, going to obey you to stop you from killing them. So, unless the invader is purely genocidal, the invasion will fail if all the pacifists stick to their principles and don't back down. Eventually it even starts to corrode the invaders troops, as over time the guilt sets in that what they're doing is pure bloody murder, and admiration grows of the pacifists sheer courage in the face of death. (Invader tries to counteract that with contempt; who knows which will win?) For real life examples, look at Gandhi, Martin Luther King, Denmark's response to Nazi invasion, and [the Addio Pizzo against the italian mafia](https://reason.com/archives/2015/02/01/gandhi-vs-the-mafia). There was an old sci-fi short story like this. I can't remember what it was called, but aside from being pacifist, the native population also didn't have currency, or a desire for it. Their economy ran off of obligation, and whenever an invader tried to make them do something, they'd say "I don't ob you". Note: to those thinking I typo'd "I don't ob you" and it's supposed to be "obey", don't edit it, it is "ob". Ob stands for obligation, which was essentially how they managed their economy -- by mentally keeping track of who owed what to whom. The invaders, being new, were owed no obligation by anyone, and being obnoxious, no one was willing let them get obligated to themselves. [Answer] The country is spread out through a jungle, filled with giant hungry raptors that don't mind the locals, but will eat anyone else that intrudes. The country is an island surrounded by kraken infested waters. The country has only one point of entry (surrounded by a mountain range), and the locals can lower a barrier or drain a lake preventing passage. The barrier cannot be passed because for example, the bottom of the lake is made of quicksand or full of monsters. The country is permanently -100 degrees, the locals have adapted via their subspecies, magics, technology etc. so any army marching on it would die from exposure. The country is very, very far away from everyone else such that no army could carry enough provisions to reach it (but a boat filled with provisions could sail there with a small crew). The land is poisoned and kills all living things on it unless they consume some plants to get immunity that are only found on the land and prepared in a certain way. Outsiders will perish upon entering the country unless they drink some of the potion. [Answer] The weapon of Loveland could just be their way of life (or ideology). They are pacifists and making their magic be the fact that proximity of others to them makes those invaders gradually become pacifists too will be a way to defend them. To make things more dynamic you can vary the strength/effectiveness of this magic on variable factors like population. For example, an army of invaders attack Loveland and as time passes a percentage of them keep defecting to become pacifists too. If an invader comes with insufficient numbers, they will end up all becoming pacifists before they take Loveland. If an invading army plans a drawn out war it will have to keep replenishing or it might lose its force to the pacifist ideology. This also means Loveland can defend its territory like others do, but since they do not have the usual violent attack feature, they have this special ability. Loveland can still be defeated with overwhelming force and and speed. Which, just happens to work in most invasions anyway. All the best @Alice! [Answer] Loveland has specialized in healing magic. They supply the best healers in the world. If a foreign country attacks them, their healers leave that country and go work for nicer employers. (This idea is taken from [the Chevenga stories](http://www.chevenga.com/)) [Answer] Loveland could be under the sea. Since most races are primarly living on land it would be a impossible to conquer. The ocean has a massive amount of resources and trade with harbortowns could be possible. They could sell the same resources as those landliving races plus corals. Loveland could also be a flying island filled with harpies. They could have resources lighter than air to gain their wealth. [Answer] I can think of two scenarios. One is to be more economically worthwhile at peace than plundered by war, not because of having a monopoly resource but because the work output of the people is valuable. Another is providing a threat of massive destruction, even if they're not prepared to carry it out. Before getting to this, let me provide a bit of background about LoveLand. ## Background LoveLand has actually had a blemished past. It used to be a [closed country](https://en.wikipedia.org/wiki/Sakoku), with no-one allowed to enter or leave, on the penalty of life imprisonment without parole (remember, no violence). However, one day [black ships](https://en.wikipedia.org/wiki/Black_Ships) entered its shores and forced foreigners to be allowed to land and trade with them. Meanwhile, several countries in the region had been [occupied](https://en.wikipedia.org/wiki/Imperialism) by raiders from far away. LoveLand decided that it should do [the same as well](https://en.wikipedia.org/wiki/Imperialism#Japan). These conflicts became [increasingly violent](https://en.wikipedia.org/wiki/Second_Sino-Japanese_War) and against [more and more countries](https://en.wikipedia.org/wiki/Attack_on_Pearl_Harbor). It [ended badly](https://en.wikipedia.org/wiki/Pacific_War) for LoveLand. Along with large losses on the battlefield, dozens of cities were devastated by bombs designed to [burn them to the ground](https://en.wikipedia.org/wiki/Air_raids_on_Japan#Firebombing_attacks), and near the end [two of its cities were flattened](https://en.wikipedia.org/wiki/Atomic_bombings_of_Hiroshima_and_Nagasaki) by a single Phlebotinum bomb each. The victorious parties occupied LoveLand. Ministers who served LoveLand were [executed by the occupiers](https://en.wikipedia.org/wiki/International_Military_Tribunal_for_the_Far_East), and LoveLand had imposed on it a constitution [forbidding it from going to war again](https://en.wikipedia.org/wiki/Article_9_of_the_Japanese_Constitution). However, the royal family of LoveLand were left unharmed, perhaps to make the occupation easier. The occupiers had no deep enmity for LoveLand, and soon drew their attention to [other wars and conflicts](https://en.wikipedia.org/wiki/Cold_War). ## Economic factors While LoveLand is not a barren wasteland, it is not abundant in natural resources. It imports food and mineral resources from other countries, and sells manufactured goods. It has become [reasonably prosperous](https://en.wikipedia.org/wiki/Japanese_post-war_economic_miracle) since its last war. One of LoveLand's most powerful neighbours is the [Middle Kingdom](https://en.wikipedia.org/wiki/China). It has been invaded multiple times by LoveLand in the past, and anger between the two countries still exist. While LoveLand does not have any Unobtainium in particular, trade between the two countries is very vigorous. If the Middle Kingdom were to invade LoveLand, not only would trade stop during the invasion, but LoveLand's ability to create manufactured goods would be harmed for a prolonged period of time. LoveLand is more valuable to the Middle Kingdom as it is with its people contributing to the international economy than as an plundered shell. [They may not like each other, but they need each other](http://world.time.com/2013/12/01/china-and-japan-may-not-like-each-other-but-they-need-each-other/). ## Deceptive threat of force LoveLand is pacifist, but its neighbours don't know that. It has a reasonably powerful military. Also, while LoveLand's government says it doesn't have any Phlebotinum weapons, and vigorously calls for world-wide disarmament of them, it currently uses Phlebotinum for [generating electricity](https://en.wikipedia.org/wiki/Nuclear_power_in_Japan). What if it is lying and [secretly has Phlebotinum weapons](https://en.wikipedia.org/wiki/Paranuclear)? The only way to find out for sure is to invade LoveLand, and the potential consequences are too [catastrophic to bear](https://en.wikipedia.org/wiki/Deterrence_theory). Both economic factors, and a deceptive threat of force, would work best if LoveLand's neighbours were large, stable, rational countries that have a lot to lose from war. It would not work well in an anarchic world with lots of small factions that are likely to act recklessly and irrationally. In real life, LoveLand (Japan) is also protected by the United States and other allies, but that goes against the requirements of this question, as that probably consists of violence by proxy. [Answer] **Scare the Pants off the Enemy** I swear I've seen this scenario a few times in cartoons etc., and can name several instances in nature where animals do this. The country would need outposts or a way of knowing the enemy were coming. They'd then need an elaborate plan to scare the enemy away. This is actually done by North Korea at the moment by broadcasting footage of their apparent military might. All they need to do is make the enemy think they're marching to instant death. A handful of ways to do this: walls made from skulls, huge displays of magic, breaking a dam or detonating an explosion to cause a huge natural disaster, not aimed at killing anyone but creating a loud sound or "sign from the gods". [Answer] If they don't have any technology or magic superior to the other so why others would attack them? In my opinion pacifist country should be nomads, so if anyone attack them, they just leave and left the empty space behind. [Answer] Combining some of the answers above: **Transportation magic**. They are really good at it. This allows them to live in a region that could not be inhabited by others effectively: a high mountain range, an underground cavern etc. They are neutral and do not have much to offer in terms of resources, but provide their transportation services to all that need it. Any attempts at invading their lands would be dealt with by * the attempt utterly failing, as any attackers are promptly teleported back home * the complete refusal to provide their services to the offending party any longer, eventually causing them to be conquered by the neighbouring countries. [Answer] One solution would be using nonlethal defense. Real life example is pacifistic caring pepper spray (rather then knife or gun). Make spell or magitech that incapacitated attacker without harming him. Another would be demotivating attacker form attacking at first place. Cast curse spell on property, that would bring misfortune on whoever steals it, deterring raiders. [Answer] **If they can produce viable offspring then** Your medieval nation will need to weave a deep network of alliances and royal marriages. If you marry your royal house into the houses of several major nobles from the regional superpower, or better yet, marry into the regional superpowers family. I am not sure how marriages work in your world, but I have to assume it is something like our world where either it is a one-man, one-woman marriage or a one-man, multiple women marriage unless specified otherwise. Since in the Middle Ages things worked more as a "by family" basis rather than a "by kingdom" basis this obliges the nobles you married into to defend their relative and her/his new land and titles. By weaving a complicated series of alliances and marrying into major noble families all over the map. **else if they can not produce viable offspring or if religion forbids inter species unions** They still have a shot. Diplomacy is still the only way to go. If your peaceful Loveland swears fealty (basically agrees to pay a tribute) to warlike nation B then nation B now has an obligation to protect Loveland. If for some stupid reason nation B feels the need to turn against Loveland, then Loveland can call other nations into the war via offering highly reduced or even no taxes imposed on merchants from allied nations and nobles. You specified no unobtanium, but also stated it was a rich land. This leaves two possibilities: Either Loveland lies on a very important trade route, or its craftsmen are unusually skilled. Either way they have a lot to offer any allies. If they have skills such as master carpenters or masons (both valuable skills of the time for castle construction) they offer state funded craftsmen to build their allies fortifications and towns. **Going another route** Rather than fighting a real war, Loveland can incite fighting between the major powers and thereby keep them too occupied to care about little Loveland, although this might not fit within your "no war by proxy" rule. A good spy network will allow Loveland to place bribes, insults, and other tools in such a way to incite small scale wars between potential enemies. This keeps them too busy fighting each-other to worry about a small, pacifist nation on their border who has never done them any harm. This route is risky, however since being discovered by either side will lead to a declaration of war. Then Loveland will fall back on the **multiple alliances** it **should have.** Ever heard the saying, "don't put all your eggs in one basket"? If Loveland is very unlucky and all of its allies turn against it (how the hell does that happen!? If Loveland had been listening to me up until this point that cannot conceivably happen!) it is screwed anyway. Very few nations could survive every other nation in the region ganging up on it, even if it wasn't pacifist. **Also** You specified orcs specifically. The allies could be coerced into sending a standing group of knights to defend Loveland, or there could even be knightly orders established to specifically defend Loveland, or generally, anyone from marauders/wild orc bands. IMO there is no way a nation can remain independent for very long without any form of violence. It could scrape by for a century or two but it would definitely not survive longer than that unless it was a religious state (see the Vatican). [Answer] **Options to prevent personal belongings from being stolen** From most effective to least * Don't have any personal belongings * Personal belongings taken will magically find their way back to you * Personal belongings cannot be unwillingly taken (*think: storing you're stuff in a magic device or portal which only you can open*) * No protection over the belongings themselves: keep them safe by running with them, putting barriers around them, or other keep-out-of-reach methods which can be defeated but are annoying to do so. * Personal belongings are easily replaced (summoning magic, or just remake) **Options to prevent (lasting) damage to homes** From most effective to least * Don't have a home * Invulnerable to damage * Homes regenerate/construct magically in short time span * Homes have annoying barriers or other keep-out-of-reach method which can be defeated but is annoying to do so * Homes are easily rebuilt (magic, or normally) **Options to preserve personal health** From most effective to least * Have undefeatable escape techniques. (time-control, teleportation, foresight, ability to become untouchable - *pass through people and objects*) * Have difficult-to-beat escape techniques. (flight, run-very-fast potion, shape-shifting) * Just keep watch and remain undetectable. (Invisibility, Illusions, magic sensors) * Have personal protection techniques which can be beaten but are annoying to do so. (Stone skin, regeneration, self-barriers) * Just give in to whatever people want - will only come to harm if harm is their goal. **Options to keep enemies from settling** From most effective to least * Prevent entry in the first place: (teleport them home, time is stopped along the border, sleeping enchantment along the border) * Prevent entry in the first place, to the best of their abilities: (barriers, misdirection, a windwall, escalator-sands moving them back as fast as they move forward) * Make unauthorized trespassing a horrible experience (take their food, swarm them with unpleasant but not deadly things, temperature magic to make them uncomfortably cold or hot (whichever is easier), set endless obstacles in their path) * Hide the "bountiful" parts of their lands, or keep it out of reach --- *There are quite a few overall strategies that can emerge from different combinations of these* [Answer] ## For those not immune to mental magic In the story *Forget It* by James Schmitz, there was an alien life form that protected itself by causing those who intended to attack it to forget. It started by having them forget a couple minutes. If they still intended to attack, it had them forget progressively more: hour, day, week, month, year, decade, etc. Some of the people in the story reverted to babyhood (mentally). It was a temporary effect but lasted long enough. Schmitz used psionics to provide the effect. In a magic universe, it could be provided by magic or deity. It's essentially a magical effect anyway. This is a non-lethal, temporary effect. So consistent with pacifism. Even if other countries can cast the same spell, it doesn't work offensively. Their own soldiers are as affected as the enemy. Not a problem for a pacifist who doesn't intend to attack anyway. This makes this a pure defensive weapon. Note that this actually reinforces the pacifism. Someone who frequently thinks aggressive thoughts will be constantly forgetting. This will be frustrating to those who are not pacifists. They will likely leave voluntarily. ## For those who are immune to mental magic You mention undead, golems, and elementals as being immune to mental magic. They wouldn't be subject to forgetting. So surround Loveland with an anti-magic strip. "What do Lovelanders call golems?" Punchline: "Statues!" Magical attackers get stopped at the edge. Because the effect is geographic, it's useless for attackers. Again, it's purely a defense. One could argue that this effect is not consistent with pacifism. So don't make the pacifists responsible for it. Someone else did it for them (possibly a deity). They just reap the benefits. ## In combination An army of humans and undead attacks. The undead are dispelled by the anti-magic strip. The humans forget until they no longer have aggressive thoughts. The Lovelanders guide the attackers back out of their area. If memories are both removed and restored magically, the anti-magic strip will prevent the effect from wearing off. So people in the strip will be stuck with no memories. If they continue on outside, they will recover. Even the combination is not completely invulnerable to attack. But it is not unreasonable to think that they might get away with it for hundreds of years. The vulnerabilities are non-trivial to exploit. Further, even a successful attack leaves the attackers stuck in a land inimical to aggressive personalities. And they can't steal any of the magic items from inside. The anti-magic strip turns them into junk on the way out. [Answer] **Golems!** Have a large *defensive* army of golems. They can defend non-violently. Consider a 5 year old attacking an adult: the 5 year old can kick and scream and bite etc., but the adult can easily restrain the 5 year old *without harming them*. A human/orc/etc. attacking a Golem would be a comparable fight - you might get a few scratches on the golem (not a problem), but the golem can easily restrain the human/orc/etc. [Answer] While we tend to use violence as a category, suggesting something is either violent or not, I have found that, when you press someone to actually define what they will and will not do, violence does not have a hard crisp edge between violent and non-violent. I have found that, when you start to dig at it, violence is more of a scale, from "purely pacifist" to "utterly violent" with everything between. As such, you might find your country more realistic if it approaches the concept of "pacifist" more fluidly. The definition I find very effective for defining violence in a way which is in line with all sorts of things we call violence (physical violence, verbal violence, etc.) is to consider the violence of an act to be how much you force the world around you to bend to your will, versus how much you seek to find a way to work with the world to accomplish a common goal. These two concepts work together quite well, because it enables a pacifist country to simply guide a warring country into a position where its violence is redirected towards itself. It's simply a matter of allowing the warring country to get their near term goals every time, while making sure the way they get those goals supports your goals (which may involve drawing the other country's own blade against their throat). Of course the devil's in the details. Nobody has written a document describing a universally successful way to do this. Everything has to be situation dependent (otherwise you are imposing your will over the world, rather than working with it, and you become violent by accident). Nations have conflict because this is so mindnumbingly difficult to do. There are a few examples, of course. Switzerland is famously neutral, bordering pacifist. Of course, if you dig into their history, you can see that they aren't just sitting back and waiting for the violence to come to them. They simply make sure their activities remain below the radar. [Answer] # Deception Although a pacifist country sounds like one with high moral standards, I saw no prohibition against deception. Any time a would-be invader reaches the borders, Loveland can put on a show like they were just invaded by a massively superior army. Scouts would report on the identity of the invaders (their race, at least), and the leaders would set up a ruse in which half the population posed as fighters from the least desirable army for the invaders to fight, and the other half posed as their newly acquired slaves. As long as it's ok to *pretend to have committed violence*, this should not violate the Lovelandian pacifist constitution. Of course, the Lovelandians would have to be excellent actors, and may even have to simulate violence against each other to make the ruse of slavery believable. But you don't need mind control magic if you have sufficiently convincing illusion magic, combined with actual theatrics (elaborate set-building, pyrotechnics, melodramatic acting, etc.). # Limitations The key is that there has to be a set of credible opposing forces at all times. If one country becomes an absolute superpower (even all other countries allied against it would fall), then this ruse wouldn't work. As long as there is possible balance amongst the viable set of invaders, each one can be led to believe that others have beaten them to the punch, and that retaking Loveland would cost too much. Obviously, the Lovelandians would choose an opponent that has access to weak areas of the invaders, to complicate the strategic calculus. Also, the Lovelandians would have to have intricate knowledge of their neighbors and the political situation in the surrounding countries. If their land is rich and bountiful, they should have the resources to run an extensive spy network, and curry favors with various nations to pump them for information. And the speed of information must be limited. If invaders can instantly check the status of their neighbors, then this scheme obviously won't work. If invaders have deep lines of communication with their enemies, then the scheme will get exposed sooner or later. # Fallback Even if the plot is exposed, the Lovelandians can simply invent a foreign invader, and be "subdued" by them. The trick is putting on a credible show of strength for such an invader. Again, illusion magic is the best bet here, as well as physical isolation. If it is difficult and expensive to get to Loveland, then they merely need to demonstrate that an invader has marshalled a very large force to occupy the country. The very presence of such a force would be evidence of its power. And isolation would help with information flow and reduce the probability of invaders attacking in the first place. Again, deception is helpful. The best bet for true pacifists is to simply hide. If Loveland lay within a rich forested area, then they only need to turn the forest into a kind of labyrinth, where explorers are led down winding paths that circle back out of the forest. The forest closest to the country proper should be made to look decrepit and haunted. Having some undead allies and wandering golems make it look like nothing but ghosts remain would help deter raiders from looking for Loveland in the first place, let alone stumbling upon it. [Answer] A long time ago, a deity -perhaps offended by the acts of some humans- determined that there was too much evil in this world/continent. So it set up a spell that intended to counter it. Now, there's good and bad inside of everyone, so it simply takes the *average evilness* of the continent population and, if it passes a threshold (nobody actually knows its level or how evil current society is), automatically kills the worse offenders. Many royal families disappeared as a result of their members being precisely those offenders when this was implemented. The country rulers reacted to this spell by founding Loveland in the middle of the continent, so they can continue with their abuses confident that the peaceful nature of LoveLand will counteract their own acts. Peaceful people move to Loveland in a similar way of how people retreat to a monastery, for praying for the world. And as long as not many people do that (how many people want to leave their home and travel into a remote country they barely know about?), the rulers will be happy with it. Anyone that attacked LoveLand would destroy this equilibrium. The head of the army is the most likely to die the first, as shows that he was so greedy that he even attacked LoveLand (and the second-on-rule would quickly retreat in order not to be next), but the surrounding countries would also fight against those putting LoveLand at risk, since that would also, if they are tyrannical, put in risk their own live style. And if they are not, would not like those Huns around, either. Do remember that even if their are quite nice rulers, nobody knows exactly what's the margin until the spell activates, or how many Lovelanders can be safely slaughtered. Even if they aren't killed or enslaved, just the anger for the intrusion *would* decrease their *loveliness*, and increase the risk beared by everyone. [Answer] **Because they are defended** Not everyone in Loveland is born loving pacifism and peace and all that stuff. *So, what happens to the ones who don't fit in?* Well, they quietly leave. What Loveland has defending itself is a sort of miasma of people who are just too sociopathic, too dangerous, too damn good at killing to live in a pacifist society, who willingly walk out into the wilderness, cut their ties to their mother country, and then spend the rest of their lives fanatically defending their birthplace. For this reason, Loveland has what can be considered the largest, most expansive intelligence/assassination network and the most powerful legion of irregular troops, militias and adventurers operating beyond its borders. These are deeply, deeply scary people. Your orc raiding parties? They never even get close. Tyrants trying to raise an army against them? They die mysteriously in their sleep. Any atrocity done against Loveland is returned sevenfold. Of course Loveland would vehemently denounce the horrible actions that are done for them. Indeed, all of these people count as at best exiles, at worst outright in rebellion. But hey, what do you expect Loveland to do about it? Fight these people? [Answer] Cover the pacifist settlement with **thick** forests and fill these forests with jaguars and venomous snakes which are mind-controlled by the pacifists (magic) to not harm them but growl and hiss loudly upon seeing any other person from far and charge at them if they approach closer. With medieval technology, it would be impossible to fight these mind-controlled beasts in a thick forest. [Answer] A superset of Youstay Igo's is to place Loveland in a location with natural barriers of some sort. Those natural barriers might make Loveland's existence unknown outside its borders or might make getting any sort of armed force into Loveland an impossibility. Natural barriers could take the form of liquid, mountains, life (think forests, wildlife, etc.), deserts, etc. For story purposes, it is probably better that Loveland remain unknown rather than known but unable to reach. My reasoning is that any sufficiently motivated, power hungry human would eventually figure out a method of crossing such a barrier to pick the "ripe plum" of a country of Loveland. Also consider that **non-violent does not mean stupid.** If conquerors arrive in small numbers, the Loveland police or militia "forces" might simply take them into custody (non-violently) and apply non-violent punishments ("you must perform 2000 hours of community service") or incarcerate them to prevent them from committing violence upon Loveland citizens. [Answer] If they do not interact much others They can be unreachable. Loveland is surrounded by a "cursed" forest where any foe will lose their way and find themselves unable to get through. Or the whole nation is on top of a plateau so high it's impossible to climb. Of course they have exclusive access to the way in and out of forest or the plateau (flying apparatus, dragon riding, magic passage, teleportation, etc). They can hide. Loveland is invisible, nobody knows where it is and its location has become the goal of many (failed) quests in the rest of the world. Or Loveland is memory proof : unless you're a Lvelander, once you leave the territory, you forget it ever existed, so nobody even looks for it. If they interact with others They have a type of magic that every other country need. Their leaders do not dare to attack Loveland and lose access to that magic while becoming the target of the others. Maybe only lovelanders have divination magic and people come from everywhere for prophecies, or they can change the weather and each year the leader that gives them the biggest bribe gets best weather for his country. Can be any other magic that is valuable, no need to be more powerful than the other's magics, simply unique to the people of Loveland. It can't be a technology since that can be stolen or copied, and it's a magic that requires a lot of people to be cast, so you can't simply kidnap and enslave one Lovelander mage for yourself. ]

[Question] [ In my stellar empire, the sapient life of the home world are arachnids. Due to an oxygen-heavy world with certain evolutionary characteristics, spider-like beings developed intelligence and formed society, leading them (eventually) to start looking toward the stars. This led to the development of space suits for the pioneering arachnid astronauts. **What would these look like? How would space suits be differently designed to support arachnids?** Let us posit that the arachnids are roughly 4 feet from "spinneret" to fangs. Their legs are large enough to support them (I don't know what that is). They're light compared to us (maybe 25 pounds at the heaviest - bear with me on the whole square cube law deal). They have roughly equivalent technology levels to ourselves at the time of our first missions into the stars. [Answer] Yeah. For the spiders, this is gunna suck, but it’s not undoable. I do suspect it will be more of an exo-exoskeleton than a suit though. There’s a couple of reasons why it won’t be particularly pleasant. The first has to do with how unbelievably sensitive spiders are. Their bodies are covered in a variety of specialised hair like structures that give them not one but two extra senses, and they’ve got extra bits in their knees that give them yet another one. The suit is basically going to annihilate any option of using those (especially the hairs for sensing air motion, which in some spiders are sensitive enough to pick up on the pressure caused by a *laser pointer*). It’d be like someone shining a light into your eyeball, but body wide. Depending on whether or not these extra senses have survived into your modern spiders and how strong they are you may need training, drugs or both in order to deal with the suits (as some people may need anti-nausea drugs to deal with zero-G) The second reason it would either suck or need some exceptional engineering is that terrestrial spiders breathe via almost all of their body. They don’t have particularly dedicated airways or efficient circulatory systems and as such are used to being surrounded by air in order to get enough oxygen into their vital organs. In other words: you need to keep a flow of air between the suit and the spider or they will suffer from the equivalent of hypoxia (which can be thoroughly unpleasant). That might not seem like an issue, but it really is. Anything pressurised in space will want to puff up like a balloon. That stops you from moving limbs, severely restricting motion. The only way to deal with it is to have rigid ‘space armour’ that air can flow under without deforming the suit, and that comes with a whole extra set of challenges around mobility/cooling. Not only that but you’ll have to have pump air around the suit in order to keep it oxygenated. Pumps vibrate. Remember those weird knees I mentioned earlier? They’re super-sensitive vibration sensors. To the poor spider inside this vibrating, solid tin can it’s gunna be thoroughly unpleasant. Manipulators are simple at least as spiders don’t have dexterous fingers to worry about. As such ‘bond villian’ claws can be added to the ends of the suit and operated using simple squeeze actuators without being too weird. Or you could replace with a variety of simple tools. And any suit umbilicals also have a natural attachment point near the spinnerettes where they can be grasped by hind legs. So basically: armoured, mechanically clawed, permanently on edge spiders floating through space. Yeah... [Answer] **They don't need a spacesuit just oxygen** Warning - Video of a spider in a vacuum chamber (it walks around and lives to tell the tale). <https://youtu.be/tA9jcIwvge0?t=243> Judging by the video, they don't even need oxygen for a short space walk. **In response to temperature concerns** It really depends where in space they are. Right next to a star they would be burnt up regardless of a space-suit. Away from any stars they would be frozen solid eventually. Their spacecraft could perhaps beam infra-red at them. However: > > At the Earth's distance from the sun, a space thermometer with roughly > half its surface is absorbing sunlight would register 45 degrees > Fahrenheit. > <https://www.space.com/14719-spacekids-temperature-outer-space.html> > > > Also many spiders can survive temperatures below freezing. > > "...About 9% of spiders in relatively mild areas remain active > throughout winter. These are nearly all Linyphiids who can still **make > a web** at temperatures as low as -1°C. ..." > > > <https://www.amentsoc.org/insects/fact-files/overwintering.html> > > > **Bonus fact** When they go on space-walks, because they're not enclosed in a suit, they don't have to worry about a connecting cable - they can use spider silk to hold them in the place they need to be. [Answer] I'm going to go in a different direction here and say that instead of making a space suit, make a space pod with mechanical spider legs. Have an enclosed pod that the spider can sit inside with legs folded and have mechanical arms/legs that support the pod and allow it to walk around. For simplicity, the pod could have 4 or 6 legs, but there could also be different pods for different jobs with a variety of legs or attachments. This has the benefit of *looking* like a spider suit, but doesn't have any of the complexity of trying to allow them to use their own legs. [Answer] # Hamster ball [](https://commons.wikimedia.org/wiki/File:Hamsterball.png) A hamster-ball for spiders allows them to breathe through their body, and move around by rolling like a hamster in a ball. Of course a simple plastic ball wouldn't allow much work to be done, but a high-tech ball could have various mechanical appendages to perform any work a space spider needs to do. [Answer] Tarantulas have retractable claws, similar to that of a cat, so it won't be a far stretch to think a spider could use these claws to fit a suit on. Tarantulas have a respiratory system that uses book lungs to process oxygen. Tarantulas process oxygen at extremely low rates. The hairs, or urticating bristles, are a defensive mechanism, early warning system(think Spidey Senses) and even a survival mechanism(some tarantulas use these bristles to create an air bubble around them, giving them potentially hours under water without the need to resurface for air). Tarantulas are generally measured in diagonal leg span(from the tip of the front leg to the tip of the opposing rear leg). Tarantulas generally become less active in the cold. Often not eating or drinking for months, or possibly years at a time. Looking for videos of "tarantula molting" might give you some ideas how they could get the suit on/off. Molting is the process of shedding the old skin. With all the above information in mind you will need to consider; Are the suits needed for short space walks or would the Tarantulas be wearing them semi-permanently? This will determine if the suit needs air, heat and durability to elements). I would design a suit where the only opening would be on the under side of the Tarantuals carapace. Allowing the Tarantula to fit it/remove it in a similar process to how it would molt. The fabric should allow the bristles to 'poke' out. The suit should retain warmth and small amounts of oxygen. [Answer] Technically, there are two main challenges with space suits. 1) Keep them loose enough and yet tight enough. Human limbs have bulgy muscles and such, to too tight and it's awfully uncomfortable. Platemail or plastic tubes wouldn't really work. For something that has an exoskeleton, this isn't a big deal, you're just duplicating that, essentially making the exoskeleton thicker. 2) Joints. Again, this is a challenge, but not too hard. Unlike with humans, all joints in a spider are relatively simple. There are two types: ball-and-socket, and hinge. Hinge (all the knees) are the simplest possible joints in engineering terms, but ball-and-socket (where legs join to body) are a ginormous pain in the ass in every imaginable engineering aspect. Not impossible, just so prone to failure. Rather than a ball and socket, probably best to make two hinge joins in a chain, at rightangles to each other. Almost as good as a regular hinge, with most of the advantage of a ball and socket. [Edit: it has been pointed out to me that arthropods **don't** have ball-and-socket, anywhere. They all do the two-hinged-joints thing everywhere, already, as I should have remembered from seeing crabs-legs. This makes exoskeletons insanely easy!] So what it should end up like, is basically just a second skin. Spiders and other arthropods are *already accustomed* to wearing second skins, and are used to getting out of them, as we see here: <https://i.imgur.com/9K95I6E.gifv> [Answer] You need to step back for an easier "in". I said in my comment to [@Joe Bloggs's answer](https://worldbuilding.stackexchange.com/a/130768/34147): > > Based on how "dull" modern humans' senses are in comparison to our ape > cousins, I'm gonna say no. We're not even all that far from > chimpanzees, and [by comparison] we have hardly any sense of touch, smell, taste, or > hearing. Sight is the only comparable sense. > > > Compared to other > mammals, we're practically cut off from the world. > > > It's hard to > imagine a technologically advanced spider being just as endowed with > senses as its more primitive ancestors and contemporaries. > > > To answer the question based on that evolutionary assumption, then, you need to answer some questions about what these spiders look like, and how they feel about nakedness. I'm not talking homburg hats and four pair of Docs, but do they have any form of clothing? What are the names of the garments? Anyway, to practical matters: * Their hairy legs can be practically bald; and wearing a suit would only be as irritating as wearing socks in bed is for me, i.e. a little bit, nothing like unbearable or overwhelming. Sure, let's say they might need to put on some form of undergarment for protection. * Their elbow/knee ears could be fed audio communications, designed into the suit, or the undergarment. * Multiple eyes could be used for different purposes, assuming the minor pairs haven't atrophied by evolution. * Breathing wouldn't be an issue. Spiders and other arachnids breathe through a [*book lung*](https://www.britannica.com/animal/arachnid/Respiration#ref495021). Human space suits are pressurized. (If you have gas, you're breathing that back in.) I would assume that spider space suits would also be pressurized. The book lung of the space spider could also have seen modest evolutionary improvements to increase the airflow. Everyday clothing is going to be your clue for how to talk about the different components of space suits, and what limitations they might impose on the wearer. There is also the problem of the spiders' home atmosphere composition. Earth's has changed over the aeons, so sure, pick something. Maybe "they need more oxygen" which is fine because "they're super-strong". Just make your excuses and run with them. Don't necessarily *declare* them to the reader, unless they need to know world/space mechanics. A couple of objections raised by others to my comment elsewhere: 1. the [human sense of smell may be physically as good as that of dogs](https://www.npr.org/sections/health-shots/2017/06/08/531744473/learn-to-sniff-like-a-dog-and-experience-the-world-in-a-new-way.), but just out of practice 2. [humans can feel surface bumps which are just 13nm high](https://www.sciencedaily.com/releases/2013/09/130916110853.htm) ]

[Question] [ One night a spacecraft of extraterrestrial origin crash-landed in the densely populated city of Philadelphia, Pennsylvania. The force of the impact leveled the entire city within a radius of 1 kilometer from the crash site. The death toll is unimaginable; the total casualties have been estimated around 300,000 and the impact left hundreds of thousands more, living up to 10 kilometers away from the epicenter of impact, homeless. The survivors do not have adequate supplies of fresh water, food, or medical aide. **Questions** 1. How does the government cover up this mess? 2. How will the authorities silence eyewitnesses? 3. How can they tow the spacecraft (the size of a double-Decker) to Area 51 without raising suspicion? **Notes** 1. No aliens survived the crash. 2. The incident happened at night. 3. Satellite images captured everything. 4. The event was caught on tapes. 5. Several human shadows were scorched into walls and ground at the crash site. 6. The spacecraft broke apart with pieces as big a mobile phone littered everywhere. 7. There is no sign of smoke trails. 8. Radiation levels are normal. [Answer] **Surely you mean the meteorite impact?** NCC news: > > Today a massive meteorite impact in Philadephia caused thousands of > deaths and ten thousands of causalites. Authorities believe that the > meteorite likely disintegrated shortly before impact explaining the > lack of remainders [possible!]. Soldiers from Fort XYZ [in reality > special ops] have already taken position to prevent looting until the > National Guard is able to send support. > > > Next news: > > The authorities are informing the population that an illegal chemical > factory currently discovered in the ruins and destroyed by the impact > may be a severe security hazard. There are strong indications that > they bunkered a large amount of sulfuric acid. Sulfuric acid causes > severe burns on unprotected skin and can even cause blindness [it is > also an essential part of chemical laboratories and coincindentally a > cleansing agent]. For > this reason protected workers are now decontaminating the laboratory > which is very near to the meteorite impact [guess that noone near that > is alive?]. Please do not approach the ruins in a 2 mile radius until > the cleanup is completed. > > > Update with survivor interviews (both fakes): *Dirty, exhausted hobo with an alcohol bottle in his jacket*: > > I saw it! I saw it! A HUUUUUGE ALIEN saucer! It told me that it would > come! This is fulfilling the prophecy! > > > *Nice, clean shaved businessman in suit, speaking normally*: > > Oh yes. A terrible tragedy! The day was suddenly > so bright! I could not look up and needed to shield my eyes with > my hands. And then it shook me and I was flying through the air! The > whole area was devastated and I could smell something terrible. I > just had to run and get out of the area immediately. > > > An expert speaks now, Professor Dr. XYZ which is the meteorite authority: > > Well you know, it reminds me of the Chelyabinsk incident in Russia > where a meteorite exploded in mid-air and caused severe damage, but > fortunately very few casualties. It is rare, but not unheard of that > no smoke trail could be seen. First, it was night during the impact > and the impact caused a cloud of smoke rising which will cover the trail. > Second, even if that was not the case the meteor is likely > composed of denser material (rock or even iron) and when the atmosphere > get more and more dense on the ground, it puts more stress on the object > which finally causes disintegration without much ablation which is > necessary for a smoke trail. [Long, long essay about deepest > condolences and the dangers meteorites pose and how perfect the > evidence is]. > > > Update: > > The authorities inform us that several tons of rubble are blocking > the streets and impede the rescue progress. Also a large amount of > binding agent for the spilled chemicals must be transported. The army has > dispatched several heavy Boeing-Vertol CH-47 Chinook helicopters which > will be able to bring out both the rubble and the agent and save human > lives. > > > Taking on problems: > > Being the first major meteorite strike with severe human losses in the > USA the authorities are surprised that the event seems to have caused > a mass hysteria. Some people insist against all common sense that the > meteorite strike was in fact an impact of an "alien spaceship" and > have posted grainy truther videos on Youtube. Psychologists have > already dubbed the new hysteria the "Philadephia syndrome". > > > Government speaker: > > We are all at a loss to what happened! Unfortunately instead of > helping other people some individuals have now used the opportunity to > spread false rumors to gain attention. We do not know why they are > doing this, but be assured: If you believe to have gathered evidence, > inform the authorities about it and it will be evaluated neutrally and > with utmost scrunity. Luckily we have now real videos of the impact > [really, really billion-dollar good CGI]. I offer also my condolences > for the surviving families that the buildings of some of their > deceased family member has not only been destroyed by the impact but > the contents of the buildings has also been irrevocably destroyed by > the sulfuric acid. We know now that Mr Hastings [single, only distant > relatives] is responsible for storing the acid. > > > Phil Plait, skeptic and astronomer: > > There have been many arguments during the years which makes the > implausibility of alien spacecraft obvious. The vast distances to > cover, the plausible reason to cover this distance, the lack of FTL > drives. And lets not forget, we astronomers look at the sky, if there > was no spacecraft there the whole time how good is the chance that > this is a real one?! I must admit that many posted videos are > extremely convincing, but given the equally valid counter-evidence we > must use Occams Razor. Extraordinary explanations need extraordinary > evidence. Unfortunately it is always the same: If we want to see the > originals, the people say that they are vanished [broken in] or > threatened by government officials with life-long prison. Do I need to > say more? > > > Some people do not understand when to give up... > > The strongest zealot of the so-called "Philadelphia Truthers" has now > died by a tragic suicide. Malcolm McCoy, who was also known to believe > in the conspiracy theory of 9/11 and has a medicine record of a > depressive episode 25 years ago always declined the charges of Mrs. > XYZ who accused him of molesting her was found dead in his home. It seems > that he repeatedly stabbed himself in the back and bled to death. > Coroners who examined the body with utmost scrutiny said that suicide > was the only reasonable explanation. > > > Some time later (we need to have a good sleep): > > We have gathered together to mourn the loss of the 17th regiment of > our Special Forces. They did their duty during the Philadelphia > meteorite strike and it is still unknown what exactly happened with the > transport plane. > > > For information: I am a [role-playing gamemaster](https://en.wikipedia.org/wiki/Gamemaster), and I use background mixed from reality with fiction. For example: What could be the real reason the Soviets used the [Czar Bomb](https://en.wikipedia.org/wiki/Tsar_Bomba)? Something terrific must be destroyed! I use then maps of the Novaya Zemlya, inform myself about the technology in the 1950s and prepare an invasion of a Great Old One which the player characters must fight. It spares me from having to invent everything, and it is also a nice history and geography lesson. ADDITION: Some people believed it that it could not be suppressed for the reason everyone has now a smartphone, so someone would take pictures and send them over the net. Guess what, it is disturbingly easy to defeat. What I am talking about are [IMSI-catchers](https://en.wikipedia.org/wiki/IMSI-catcher) which impersonates a mobile cell, can intercept any attempt to phone and is also able to locate the person immediately. So if you wandering into the zone with still a working ISMI-catcher your smartphone is worthless. Worse, the supervisors could immediately detect your presence in the area and find out your identify at once. So in effect the smartphone is a severe disadvantage. [Answer] You're doomed. # Too slow to react This isn't an event that you have planned or anticipated. So you need, yourself to gather intelligence on the event before you can take any measure. Typically, you'd want a no-fly zone, no access, etc. But even in a country as developed as the USA, this would take some time. Imagine a reaction along the lines * Crash happens! Boom. * Fire dpt., ambulancies, police are sent to the spot (it'd take at least 4-10 minutes). Press will arrive more or less at the same time. * The size of the impact is reported to higher-ups, assuming the chain of commands hasn't completely been disrupted. * Within 15 minutes (and that's an optimistic estimate), the government is informed that something happened, and that's not just a gas pipe exploding. * Specific enquiry is made from the federal level to collect information about what happened. CIA is contacted about possible terrorrist threats. Air controller of the region are contacted about possible planes crashes. * UFO pieces are collected **and** identified as alien origin. That would take at least 15 minutes more. * The government realise that something very unusual took place, and decide for safe-measure to block access to the site, stopping research of injured, dead bodies, etc. Delegates a special force on-site to enforce the measure, and resume the investigation. * A no-fly zone is instigated. A very optimistic estimate would amount to 1-2 hours before everything is secure. Before then, several thousands of people have had access to the site. # Too slow to clean up To avoid some insurrection, you have to show that you continue to try to get all the victims out of your protected area. The no-fly and special squads aren't popular. That's also when you have to deliver your cover story, as well as gather evidence yourself, listening to eye-witnesses. You might not be familiar with the story, but last March, a [plane crashed on the mountains in France](https://en.wikipedia.org/wiki/Germanwings_crash). The outcome was similar to what you describe as pieces quite small spread over a large area. It took several weeks to remove all the pieces. Your UFO being larger, and the pieces being smaller, you're up to 1.5-2 months of work. During that time, you keep a no-access zone, which is going to be extremely suspicious, to, at least, intelligence agencies from foreign countries. Plus you have to explain to your NATO allies, why you refuse the help they offer. # Too many witnesses You can count several thousands of witnesses who saw the decker fall. Injured victims or neighbours might have some information related to it. Several thousands of people, who had access to the site, claim to have seen some strange items lying on the ground, etc. Consider the numbers for * people who actually saw the UFO crash, * people who saw the UFO on their radars, * people from the help that came in immediately, * people from the press who were on-site before it was closed, * by-standers during the first phase of the emergency, * etc. Those are numerous and hard to track, you could have people who were merely driving through at that time, who came from far, as the first information came out, etc. # Too many factual evidences The UFO was probably seen and recoreded by many people, satellites, radars, etc. Plus due to the time before you could control the access, many people could film the site. From all those footage, analysts will explain that only the crash of a large object could explain it. So your best chance it to talk about a meteorite at that point. But the fact that you kept the site closed, even to allies means that this is more fishy than it would sound. During the Fukushima accident, several foreign teams were sent there to assists the Japanese. You refused such help. On what grounds? It is likely that someone, took one or more of the alien's ship pieces from the site before you could close it down. [Answer] It was clearly a terrorist attack! Evil terrorists placed thousands of tons of explosives in a warehouse in central Philadelphia and blew it up. Why? Because they hate our freedom! Time to invade... hm... let's pick Iran. What? You want proof? We have full confessions of the terrorist leaders. They confessed after we picked them up on the street of Teheran and tortured enhanced interrogated them for a few days. Didn't you see it on FOX News? Why couldn't all our three letter agencies protect us from this terrorist attack? Because they are chronically underfunded. Thank the liberals of [other party] for cutting their budget again and again. Our agencies need far more money which we will finance with a new patriot tax. Also, their hands were tied by all kinds of unnecessary formalities. *"No searches and seizes without warrants"*? *"No arrests without reasonable suspicion"*? *"Right to due process"*? *"Right to a speedy and public trial"*? How are they supposed to catch terrorists when they have to follow all those rules? It's about time we abandon that silly 18th century "Bill of Rights" hippie nonsense and build the modern 21st century police state we always wanted. Aliens? Ridiculous, that's just a conspiracy theory made up by some nut-jobs. Whoever claims that is likely an unpatriotic traitor and a terrorist too and should be silenced. You are not a terrorist, are you? Well, better safe than sorry. Agents, make him disappear. **Out-Of-Character answer:** Frame whatever group you currently want to frame for political reasons and seize the opportunity to call for legislations you always wanted but couldn't convince the public of. [Answer] **Spin the event as a natural disaster *and* as a nuclear terrorist attack** then make sure to secure the actual crash site as quickly as possible. This will be harder to do the more wreckage remains. Spinning the crash as both a terrorist attack and as a natural disaster will prevent the world from forming a cohesive idea of what has happened and buy more time to secure the wreckage. Calling the crash a terrorist attack will also give you cover to secure the site. The level of destruction surrounding the site will require earth moving equipment which can be conveniently used to break down and ship out the wreckage as it is chopped up. ## **Handling Drone Over-flights** Demand for footage of the crash site will drive some to fly their camera drones into the no fly zone. This must be strictly guarded against with stiff penalties and active countermeasures to shot down or otherwise deny access. Eventually, a drone will get through so prepare spin coverage for that eventuality. ## **Silencing eye witnesses** You may not have to. Witnesses close enough to the crash to have seen what happened are dead or so injured they can't offer any testimony. Witnesses far away from the crash will only know they saw a giant explosion. You will need to secure any security camera footage from around the crash site that survived. ## **Wreckage Handling** Wreckage handling is only a problem with large pieces that can't be carried by a human. The hard part of small debris will be gathering it all up. Getting it off site is a piece of cake; just put it under a pile of building debris on a truck then move it off site in a truck. Just send out the National Guard with orders to pick up every single piece they find. However, a wreck big enough to level Philly is going to have to be cut up and moved. Moving that much mass will require lots of trucks and heavy equipment. But, given the massive amount of damage to the surrounding steel and concrete buildings, it shouldn't be difficult to mix in wreckage debris with the building wreckage. ## **Scientific Resolution** Ultimately, this will show up as a crash since the firey descent trail can't be explained as a terrorist attack. No one but space fairing nations can loft stuff high enough or fast enough to create that kind of descent trail. The scientific community will want to know exactly what happened and try to recover meteor fragments. Denying them access to the site once everything has cooled off will seem really odd. Ultimately, I'm not sure you can completely cover up the crash of an alien vessel that wrecked a significant portion of a major US city. Perhaps forestall disclosure for a while but not completely prevent. [Answer] While the meteorite story is the most plausible, it is not allowed by the notes, specifically no. 7 "no smoke trails", no smoke trails means no fire ball, and thus no eye witnesses to indicate something fell from the sky. The best option from a security stand point is a lab investigating zero point energy or antimatter had an accident. This explanation would allow for the movement of national security forces into the area and create valid cover for removal of all debris (for security and safety reasons), it also accounts for the radiation levels, and the shadows on the walls (nice touch don't you think). the rest is just the usual smoke and mirrors of any chaotic situation. "Nothing to see here, move along". Of course a large emergency response is required to help the survivors and injured, but given the fact that a kilometer radius from impact is a large area, and given that NORAD would have given warning at least 30 minutes (if not more) in advance of impact, the security response would be already in the implementation phase to keep people out of the actual area of interest. Body collection would be horrific, but with the debris collected (24 to 48 hours at most), ordinary emergency responders would be allowed in to clean up the rest. Now the real question here is, the motives of the poster of this question. are we doing the work of some alphabet agency by giving them plausible scenario's or are they just using this as a means to identify the ones who would see through the false flags (us - bwahahahahaha) [Answer] The key point is **What does everyone *actually* know?** - and then controlling what they learn and how they interpret it. I don't live near Philly, so anything I'm going to hear about this will be via news reports. I'm literally only going to know what the media tells me. Easy-as-pie in this world of gag orders and national security letters. On the other extreme, anyone close enough to get a clear look at it was likely in the blast radius and thus not in a position to talk to anyone. In the middle are folks who would have saw the streaking light coming down. (Think of that meteor that hit Russia a few years back - even the folks who had cameras pointing at it just see a bright something coming down, then big boom). You simply call it whatever you want it to be called - meteor, nuclear attack, whatever your sneaky government masters want to spin it as. (And even from a kilometer away, you're not going to see much detail, particularly at speed) You mention that satellites caught details. While I think you're overestimating what a satellite can capture (relative speed is a bit of a bitch in photographing things in orbit, especially unexpected things), most of your serious cameras are government controlled. The rest are corporate, which brings us back to government nastygrams telling you that you had an unfortunate data outage, and you have NO IMAGES FROM THAT POINT OF TIME. Now, you just have a disaster scene, and it's pretty easy at this point. Lock down the area, close the roads, send in FEMA and the nuclear guys and everything else. Rig some gadgets to make clicky noises and declare an emergency evac. Get everyone out. Meanwhile, a bunch of MIBs in hazmats happily take care of the "suspect material". To sum up: 1. People close enough to positively identify what it is are dead. 2. People in the neighborhood to get a good look are busy trying not to be dead, rather than walking a kilometer into the blast zone - and can be easily sent elsewhere "for their safety". 3. Anyone beyond that only know what you tell them. [Answer] The government can present this as a crash of a secret experimental plane. They can say that some people died. They can let false witnesses tell false stories about the incident, also agents can pretend to be grieving family members of the victims. If they get on t.v. very soon after the incident, then it is known from psychological studies that this can influence the memories of real witnesses. To make this all very credible, some of these people should express anger at the government, some of them can actually hint at a conspiracy where the government is trying to cover up things so as to not have to pay out to the victims. Not everyone will say such things, but this is then enough to generate some news headlines in some sources that the government is failing yet again etc. etc. Basically, the government activates the dormant memes in society that are usually relevant. There will be plenty of room to fill in strange tings that have been seen by the unconventional nature of the secret aircraft. While some people will tell stories that suggest that it was an alien aircraft, that view will not make much headway in the media. [Answer] The answer is quite simple. The government can play it for what it really is, a 'UFO' crash. As there are no Alien survivors, there is no factual evidence that is was actually extraterrestrials. The crash was simply a military exercise that went wrong involving a top secret UFO-Shaped aircraft. Easily plausible as a lot of military exercises are done at night. As radiation levels are normal there are no suspicions. The rest is just played out like any other plane crash. [Answer] I suggest mixing some of these answers: An unknown object (probably an asteroid but could be space junk) has hit a classified advanced military satellite causing it to crash. The bonus of this setup is that the root cause is natural so the government isn't totally to blame, and the satellite explains the weird wreckage and explosion. You can also add confusion by saying that it's not clear that the satellite caused the explosion or that the unknown object also impacted the earth (by dragging the satellite in the same direction). There are many scenarios experts could give which makes it a difficult story to analyse and get to the truth. Add in the media spin that others have posted and I think this satisfies the government's needs. [Answer] The explanation needs to be simple, plausible, loop in as few people as possible, and explain the need for ongoing secrecy. I would go with a classified military satellite deorbiting. * Satellites can be quite large. * Explains any advanced technology people find. * Explains why the government is paranoid about collecting every little piece. * You can get local law enforcement providing security and low-ranked national guardsmen looking for pieces and they won't question it. * People will be attacked as unpatriotic if they ask too many questions. [Answer] ## War with North Korea, IS or Iran The government will be too slow to react. They will need at least a day to figure out for themselves what has happened and by that time, the footage will be all over the internet. Eventually they will just send in the military to control the site and muscle everybody out. After a day or two of saying that the investigation is under way and we shouldn't draw conclusions prematurely, the president will finally hold a press conference and declare that the evidence is clear: this was an ICBM with a nuclear warhead, launched from one of the countries above (whichever one is most probable at the moment, least popular, and most likely to cause a lengthy quagmire). The president declares war immediately, and gets some quick "coalition of the willing" on board to get a semblance of international support. The war is then used as an excuse to "temporarily" limit internet activity and unnecessary free speech. In the state of national emergency, the CIA can slowly go about their business of sanitizing and massaging the record of information. Various sites claiming to possess evidence that the war was started under false pretences will be shut down because they were discovered to be run by enemy spies. These efforts will escalate the US into a more totalitarian state, but the uncertainty will be effective enough to make everybody think that the UFO theory is too fantastical to be true. Any national and international enemies created along the way can easily be silenced using the technology gathered from the crashed spacecraft. [Answer] I think the worst problem here is the potential for alien machinery to leave the area in a pocket, purse, or backpack. Odds are good it's *clearly* alien in origin, so if a few dozen people get out and start taking these things to universities and so forth, people are going to find out about it. If thousands of people have samples from the spaceship, it's all over. You say the spaceship broke up, but where did it break up? If it just sprayed metal around after crashing, it's plausible anyone close enough to get fragments before the government sealed the area was killed by the explosion. If it broke up while entering the atmosphere, it's pretty much game over. When the Columbia broke up, there were fragments scattered across hundreds of miles, and it would be impossible to track them all down. Even the SpaceShipTwo, traveling at much lower speeds, fragmented over 30+ miles. I have a hard time believing that fragments of any substantial size survived ground zero of what amounts to a nuclear detonation. Any fragments would seem to have necessarily broken off at a fairly high altitude, meaning they would be scattered pretty extensively. Some of them wouldn't be found for decades or even centuries. Some would never be found. ]

[Question] [ **Is it possible for a plant to have the ability to fly?** More exactly, the plant would either need to live without having any roots (and it would never need to touch the ground), or with the ability to re-root itself in another location from time to time, or maybe a plant that has a permanent pedestal/base that it could detach itself from to avoid a predator or to hunt like a carnivorous plant. The plant would also need to ability to control its altitude, and keep it from floating higher and higher (or if it needs to re-root, to be able to come back down from the air). The setting does not have to be on Earth but it must be able to support life. Bonus point if it's possible on an Earth-like planet. Examples: * [Deku scrubs](http://zeldawiki.org/Deku_Scrub) The Business scrub is a plant that can fly with the propeller on its head. * [Peahat](http://zelda.wikia.com/wiki/Peahat) Has a base it can return to after hunting. The propeller is under the plant. I suspect that neither of these two plants can fly for very long. [Answer] It's more likely there could exist a plant which has a flying phase of its life-cycle.  **Does it really fly?** It might be more appropriate to call it floating, since the energy required for what is more traditionally thought of as flying, would be too much for a plant. Blimp plants/animals have long been imagined in science fiction, called [living gasbags](http://tvtropes.org/pmwiki/pmwiki.php/Main/LivingGasbag). It's also an interesting idea about [alien life](http://news.nationalgeographic.com/news/2005/05/photogalleries/aliens/photo7.html) on planets with low gravity or thick atmospheres. **The plants will use hydrogen, not helium** Despite the relative safety of using helium as a lifting gas, at least for Earth, it's very unlikely a plant could extract much helium from the atmosphere to thrive. Besides, helium is a noble gas, it's the least reactive element. There isn't a chemical process that any plant can use to collect it. Far more likely, the plant would use hydrogen gas. It would give slightly more lift and the plant already produces it during photosynthesis. Someone is going to cite the Hindenburg and claim plants would suffer the same fate, that's very unlikely, the plant would simply be a bit more flammable. It's like pointing to a forest fire and saying clearly plants wouldn't make themselves out of flammable materials if they want to survive. **What does it eat?** If it's a carnivorous plant, it's more likely to be something like a jellyfish floating in the air. Capturing unaware birds and insects. There is a version of these carnivore-hydrogen-gas-bag in Shards of Honor by Lois McMaster Bujold. [](https://i.stack.imgur.com/44MeL.jpg) [Answer] Well, it all depends! :) There are [tumbleweeds](http://en.wikipedia.org/wiki/Tumbleweed) which grow, produce seeds, then die, break off and the whole plant moves by the wind, depositing its seeds in different ways, it's sort of like flying. Of course seeds fly all the time, dandelions and other similar flowers, Maples have their little helicopters. However, for plants to fly, first they need help. It is unlikely they are going to flap leaves and take off. So they will most likely be dependent on the wind. One thing that could work would be parachute/umbrella type features that can carry the plant away, or at least enough of it to continue surviving when it lands. This could be a cross between a tumble weed and say a [Jade](http://en.wikipedia.org/wiki/Crassula_ovata) plant. You can break off a piece stick it in the dirt and it will root and become a new and separate plant. Otherwise maybe you have a steppe where there is always a lot of wind, and a plant that is threatened (by animals or drought) could clip its roots and catch the prevailing winds to move, it could open and close its umbrella/wings like petals on a flower and so fall back to earth to try rerooting. [Answer] One example of such a thing would be an **airship-plant** So I will start with the biggest problem: **which gas should it use?** * Hydrogen: On Earth, Hydrogen is rare in the atmosphere, but a plant may be to extract it from water. * Helium: Helium is also rare on Earth, and it doesn't react with anything. That means that in order for Helium to work is in an atmosphere that is richer in Helium than ours. That shouldn't pose a problem to the general chemistry of the atmosphere. To refine Helium, a plant basically has to take a big gulp of air, and then kick everything that is not Helium out. That can be done thanks to a semi-permeable membrane (which is used IRL), or thanks to any chemical process you like. However such a big concentration of Helium is unlikely, because it would tend to escape the atmosphere [and it *may* accumulate in the upper atmosphere, and not at ground level]. I can see two things that would try to mitigate this: + a colder planet, where Helium would have less kinetic energy to escape from gravity, + a planet further away from the sun, where solar wind wouldn't be as strong. * methane could be used. * finally, there is also the possibility to use hot air, heated either thanks to some sort of lenses, or thanks to a chemical process. All in all this seems rather complicated on an earth-like planet, but it could work better on an analogue of [Titan:](http://en.wikipedia.org/wiki/Atmosphere_of_Titan#Composition%22Titan%22) there, the atmosphere is made of 98,4% nitrogen, 1,4% methane (up to 4,9% at surface level) and 0,2% hydrogen, making light gases readily available. **Reproduction** Well pollination still works :) You have to be careful that seeds do not though. However one could imagine that instead of a fruit, plants produce an already-formed baby-plant together with its balloon. Sort of like a stolon, which would then break when the new plant is mature-enough. **Water** Depending on the climate, those plants could harvest water directly from the atmosphere, or they could stock it when it is raining. **Nutrients** Plants heavily depend on soil in order to get nutrients. But a flying plant would have to carry it with itself. A good way to do that would be to use bird poop. Birds would have a huge advantage by living on your plant: they are free from many predators. The plant could also lure them by producing fruits or something like that. **What would it look like?** Your plant has to stock water, nutrients and helium. How can all that fit? The problem is that you can't put much on top of a balloon, or the balloon will quickly become unbalanced. One solution could be to have a torus-shaped balloon. With roots forming a cone beneath it. The cone could be where water is kept, and the roots would form a good place for birds to make their nests. The good point is also that it means that the top of the balloon is free for the plant to grow leaves to do photosynthesis. -- optional idea -- Rather than birds (or on top of it) your plant could use insects. The good thing is that insects are small enough that even a small plant could use them. Moreover you can imagine huge millennium-old-plants pushed by the winds, and that travel together with a swarm of insects, which would leave a trail of devastation on its way. [Answer] If you are imagining plants that spend their entire lifecycle in the air, the genus [Tillandsia](http://en.wikipedia.org/wiki/Tillandsia) would make a good template. Tillandsia do not "fly" but grow without soil and collect the nutriets they need from the air (e.g. dust, dead insects, leaves) through special structures in their leaves. [Answer] No. **Plants are optimized for life which does not require movement.** It makes sense that [eukaryote cells](http://en.wikipedia.org/wiki/Eukaryote) are split to plants and animals (and fungi, and more but anyway). **Life requires optimization and compromises.** Once you start optimizing for one feature, other competing features lower your lifeform fitness in your selected niche. Plants are optimized for life life which can be powered by photosynthesis — and [this question/answer about green men](https://worldbuilding.stackexchange.com/questions/11103/big-green-men-from-earth) explains why the amount of energy available from photosynthesis is not enough to power kind of active life which animals do - and flying is rather extreme in that sense. Plants deal with the **meager energy input from photosynthesis by NOT spending energy to move, and have rigid cells walls** (unlike animals) so they don't need even energy to stand still. But they do capture sun energy and provide sustenance for everything else on Earth (roughly). [Answer] Larry Niven postulated [Stage Trees](http://larryniven.wikia.com/wiki/Stage_Tree), trees with a solid-fuel rocket as the trunk. I guess interplanetary travel counts as flying. :-) In addition, in the [Smoke Ring](http://news.larryniven.net/biblio/display.asp?key=198) (not a planet, but a habitable earth-like [gas torus](https://en.wikipedia.org/wiki/Gas_torus)), everything, including plants, needs to be able to fly, including the massive [Integral Trees](http://news.larryniven.net/biblio/display.asp?key=66). [Answer] # Silk flight If flight does not need to be sudden or often, the [method that spiderlings use to fly](http://en.wikipedia.org/wiki/Ballooning_%28spider%29) may be plausible for a plant. Simply producing silk (or a similar strong, lightweight liquid solidified by tension) will allow a thread to build up pulled by the wind, until it is long enough that the wind lifts the plant into the air. A number of such silk glands at different positions on the plant would reduce the required length (and hence the required open space for lift off). This approach requires only that the plant be able to produce a suitable liquid for thread formation. The rate of production can be low, with the thread slowly extending over a period of days or weeks before sufficient lift is achieved. ### Initiation Although the wind provides the required tension once the thread gets going, a small amount of tension is required at the start in order to get the thread going. Spiders can use their legs to pull the thread out until it is long enough to release to the wind, but moving parts are very expensive for a plant. A less resource-intensive approach would be to start the thread with a weight to pull it downwards. When the silk gland is mature, the tip of it is dislodged by the surrounding tissue drying out, and as it falls it pulls the silk liquid taut, turning it into solid thread. The weight is heavy enough to pull out new thread, but light enough to be caught by the wind to continue the thread growth rather than reaching the ground and stopping. The shape of the weight can be wide and flat and possibly feathered, to make it catch the wind despite being heavy. Once the thread is long enough to reach further up from the ground where the wind is stronger, the strength of the wind breaks off the weight and the thread flies without further need for it. This keeps the thread light and reduces the length required for lift off. ### Evolutionary path Since this arrangement only gives rise to flight when complete, another reason is required for the evolution of silk glands and feathered weights. For example, the silk may have first developed as a sticky liquid to trap insects (either as prey or simply to kill pests and parasites). Alternatively it could have been used to attach seeds to passing animals that brush against the plant. Over time the silk glands increased in size and allowed longer lengths of thread to be produced. The selective pressure causing this may have been that seeds hanging from longer threads attached to passing animals were more likely to get caught on vegetation and removed above ground, rather than in the animal's cave or burrow where there is no light. Being removed earlier would also be an advantage if some animals are inclined to eat the seeds during grooming. If the threads were used to trap pests and parasites, a selective pressure may have been that a longer thread meant that the struggling insects moved around more, attracting natural predators that would help keep the plant free of pests. Either way, the threads produced eventually become long enough to catch the wind, and then selection can act on that. The feathering of the weight to allow catching the wind could then feasibly develop without alternative explanation, but it may already have started in the form of mimicking the insect pests in order to lure them to the silk glands. This would mean that no insect is required in order to start the thread. In evolutionary history it may have been insects that dislodged the weight and triggered the thread production, but eventually the weight could be released independently, giving finer control over the timing (and making it more likely to happen during high winds). As an intermediary stage, they may be plants that form threads not long enough for flight, but long enough to entangle in animal fur/feathers so the whole plant can hitch a ride that way (probably only for short distances while the disgruntled animal makes efforts to dislodge it). Over many generations the thread becomes long enough to catch the wind and preclude the need for an animal. ### Size and weight Spiderlings are very small. Similarly, silk flying plants would be limited in size. In an Earth-like setting, these would likely be tiny - perhaps like mosses that do not need permanent roots and can colonise places beyond reach of most other plants. If you wanted larger plants (perhaps "kite trees"), then you would need a much denser atmosphere. If you imagine a branching evolutionary tree, then even an Earth-like setting could have larger silk plants, but only the smaller species would be capable of flight. So then you could have kite trees with long threads trailing off into the sky, serving some other purpose like those described above. Their tiny relatives would produce far fewer strands but would take flight whenever the wind picked up, unlike their huge deep rooted cousins. [Answer] That Peahat looks like [this swimming anemone](https://www.youtube.com/watch?v=Dm98n3908QM), and [anemones are half plant](https://web.archive.org/web/20160520080055/http://news.discovery.com:80/animals/sea-anemone-animal-and-plant-in-one-140318.htm): > > Sea anemones are classified as being animals, but two new genetic > studies have found that these water-dwelling creatures are technically > half plant and half animal. > > >  Depending on densities, similar beings could fly on alien planets, harvesting nutrients from sky and soil, and perhaps even hunting other organisms by smell. Earth also has self-propelling plants, albeit [in spore form](https://web.archive.org/web/20170330185905/http://synearth.net/2013/09/11/walking-and-jumping-plant-spores/): > > Before this study, it was not clear what the function of the [horsetail (Equisetum)] spores' > leg structures was. > > > "People assumed they were like wings, so they would help dispersal > into the wind," explained Dr Marmottant, > "but here we show they actually induce motion on the ground." > > > "And more importantly, they also enable jumps, which means [the > spores] can enter the wind currents. And once you're in the wind current, you can travel long distances, > which is an evolutionary advantage, because it means you can disperse > your [spores] very widely." > > >  These features appear to have been combined in [Emrakul, the astral abomination](https://web.archive.org/web/20151207113645/http://archive.wizards.com:80/Magic/magazine/article.aspx?x=mtg/daily/stf/88):  [Answer] A problem with your question is the definition of "plant" (see [Wikipedia](http://en.wikipedia.org/wiki/Plant)). If you use something like "rigid cell walls and photosynthesis" as your definition, the plant might have some sort of sensory organs and limbs like the Venus Flytrap (see [Wikipedia](http://en.wikipedia.org/wiki/Carnivorous_plant#Snap_traps)). Real plants don't have enough energy to flap their wings and fly away, but a fictional plant might do it. Another idea would be a plant which generates hydrogen to fly like a gas balloon. [Answer] Yes it is quite possible. Look further for details "Buckminster Fuller"s [Cloud Nine](http://en.wikipedia.org/wiki/Cloud_Nine_(tensegrity_sphere)). Geodesic spherical cities floated by only a few degrees hotter air inside their sphere. It works in any gas mixes or atmospheres. It works even in pure hydrogen atmosphere (you can fly hot hydrogen balloon inside it)... In sphere, area increase by power of 2 but the volume increase power of 3. There is no matter how heavy or how large the plant is. It can always cover enough volume to float itself. Larger is better, because you need less temperature difference to produce enough lift to float. So you only need massive spherical plants, structural integrity and a way of keep their inside warmer than their outside in any atmosphere. Like drifting [sargassum](http://en.wikipedia.org/wiki/Sargassum) or stationary coral reefs, they can host whole habitat / ecosystem of their own (symbiotic,parasitic, etc...). [Answer] You could have plants that fly instead of float. Something like a biological spring that winds up, and when the plant has produced enough seeds and such the root releases and the spring unwinds spinning some kind of propeller like a Deku. The flight would be short, but one interesting use would be as a kind of land mine. While it's flying and spinning it's also spraying seeds like bullets in all directions. There are earth plants that can move rapidly, but if you want something that can hunt it has to have some amount of intelligence. Things like venus fly traps move quickly when their trigger hairs are twitched, but they react to outward stimuli, not intelligently. <http://news.nationalgeographic.com/news/2005/05/0526_050526_extremeplants.html> You could have some kind of plant/animal hybrid with different life cycles. Grows from a seed, stays rooted until it's animal level intelligence matures, then flies for short bursts looking for prey. when it makes a kill it takes nourishment from the fluids and plants seeds in the corpse to grow new plants. It could even hunt with the seeds, firing the seeds at prey. The mistletoe plant does something similar to spread it's seeds from tree to tree. Other plants have similar mechinisms: <http://www.virtualherbarium.org/GardenViews/GoingBallistic.html> [Answer] Yes, but why would it? The question isn't so much *could* a plant fly as many plants do at some stage (usually as seeds) or even *how* could a plant fly as there are any number of ideas about that, personally I like the hydrogen gas method. But what evolutionary situation would make it profitable for a plant to leave behind the abundant nutrients and water of the soil for the sterile and arid sky? I'd suggest that if you want flying plants the sky has to be a rich and rewarding environment, have a look at Larry Niven's *[The Integral Trees](https://en.wikipedia.org/wiki/The_Integral_Trees)* and *[The Smoke Ring](https://en.wikipedia.org/wiki/The_Smoke_Ring_(novel))* for some ideas about plant life in the endless sky of a [gas torus](https://en.wikipedia.org/wiki/Gas_torus). As for flying plants on an Earth like world you could see that *if* there was enough ground predation to make the sky the safer option *and* there were enough resources to survive in the air, a slightly thicker wetter atmosphere would help there. The thing I would expect to see the most would be plants where part takes off when threatened, fly only a short distance, and settle again, a bit like a skink shedding it's tail to escape a predator. [Answer] Just as an another point of view: did you take a look at <https://en.wikipedia.org/wiki/Aeroplankton>? It contains moses, bacteria, liverworts, viruses. Same principle as with regular planctons does apply. In short: Plants small enough to drift in the wind is one way to go. ]

[Question] [ I am preparing world for my novel. One of the races in my world is elves. To make my world believable I would like to incorporate the Elvish language. I am big fan of Tolkien or Sapkowski's Elvish language. However as their work is copyrighted I believe I cannot use these. Is there something like an Elvish language that can be freely used in other works? EDIT: To clarify my intents: I personally think it would be cool if there were conlangs for such commonly used races as elves (or others). If there is something that can be shared across multiple universes, it might be a good factor for geeks to maybe even learn that language. I am not speaking only about Tolkien's Elvish, although that is probably the most complete one. This is why I am talking about **open source** rather than **free**. I am a software developer so these terms seem pretty descriptive for me. It doesn't even have to be always the same language - there may be different dialects and anyone can make slight customizations (in open source terminology **forks**). These customizations can be incorporated under certain conditions in the main "branch" helping to make the language even more developed - for example, expanding vocabullary. I don't want to "bypass" copyright. I think it is fair for authors to protect their work if they want to do so. But if something like this already exists, I am willing to use it and help to add new words to the vocabulary etc. [Answer] # All Elvish is (probably) open source (in the US) There is a real legal history of battles over open source languages, two threads of which are relevant here. The first is that the US court system has definitively ruled that it is not a violation of a constructed computer programming language's copyright to write a new computer program using the same language and grammar. Although there have been no definitive cases regarding 'conlangs' (constructed languages), the other thread is the situation of the legal battle over *[Prelude to Axanar](https://en.wikipedia.org/wiki/Prelude_to_Axanar)*. ### General background information There was a journal of Tolkien's linguistics titled *[Tyalië Tyelelliéva](http://tolkiengateway.net/wiki/Tyali%C3%AB_Tyelelli%C3%A9va)*, originally hosted on GeoCities and now gone. This journal published original works in Tolkien's languages in addition to other analysis, but evidently ran afoul of Tolkien's estate which in 1999 took the stance that Quenya and Sindarin in particular (and presumably all Tolkien's languages in general) were copyrighted. The journal publishers sought the legal advice of the General Counsel of the National Endowment of the Arts who sent back a legal opinion. [Here](http://www.oocities.org/athens/parthenon/9902/legalop.html) is the only link I could find of this opinion; much of the hard evidence of this whole situation is shrouded in the mists of lost GeoCities. The main points of the opinion were these: * Words, short phrases, names, symbols, typefaces, and variations of lettering are not subject to copyright protection by [37 C.F.R. 202.1 (1974)](https://www.copyright.gov/title37/202/37cfr202-1.html) [that is the title of a US Congressional act] * "In no case does copyright protection for an original work of authorship extend to any idea, procedure, process, system, method of operation, concept, principle, or discovery, regardless of the form in which it is described, explained, illustrated, or embodied in such work." ([17 U.S.C. 102(b)](https://www.copyright.gov/title17/92chap1.html)). * Tolkien's languages, by his own self-admission, derive significantly from extant or extinct world languages, which are of course not copyright-able. The fact that many proper nouns like 'Osgiliath,'Theoden', and 'Celebrian' have an origin in real, historical languages makes claims of 'originality,' which is a necessary pre-requisite of copyright, difficult to establish. * "...the fair use of a copyrighted work, including such use by reproduction in copies or phonorecords or by any other means specified by that section, for purposes such as criticism, comment, news reporting, teaching (including multiple copies for classroom use), scholarship, or research, is not an infringement of copyright." ([Title 17 U.S.C. 107](https://www.copyright.gov/title17/92chap1.html#107)) The author of the legal opinion thinks that a journal with original poetry constitutes fair use. The journal in question here evidently folded around 2001, and no court proceedings (so far as I can determine) were filed on either side, so this is just background information and not legally binding. For more background information, a more exhausting study was made by *[Harvard Law Review](https://consumermediallc.files.wordpress.com/2016/04/27harvjltech543.pdf)* in 2014. A longer read, this summarized existing conlang legal actions (there have been none that actually went to court), and comes to the conclusion that copyright law is ill-suited to regulation of a constructed language, although it stops sort of giving an opinion on the legality of third-party usage of a constructed language. ### The case of computer programming languages In general, the grammatical principles of a computer language are not copyrightable. If a Python 'Hello World' program looks like ``` print("Hello World") ``` there is nothing preventing me from writing a programming language and/or compiler that uses the exact same syntax to create the exact same effect. This is the decision of [Computer Assocs. Int'l, Inc. v. Altai, Inc., 982 F.2d 693, 720-21 (2d Cir.1992)](https://scholar.google.com/scholar_case?case=6976925648486076739&hl=en&as_sdt=6,47&as_vis=1). Following the Supreme Court decision [Baker vs. Selden](https://scholar.google.com/scholar_case?case=16308210976883953911&hl=en&as_sdt=6,47&as_vis=1) which "denies copyright protection to expression necessarily incidental to the idea being expressed", this case settled on the 'merger doctrine' which states that > > [C]opyrighted language may be copied without infringing when there is > but a limited number of ways to express a given idea.... In the > computer context, this means that when specific instructions, even > though previously copyrighted, are the only and essential means of > accomplishing a given task, their later use by another will not amount > to infringement. > > > So if my programming language wants to use the exact syntax ``` print("Hello World") ``` there are only a limited number of way to express this idea, and I can copy a copyrighted work (such as a copyrighted Python program that uses that exact line of code) without infringing on the copyright. By this logic, if a court would apply it to conlangs, which has not yet been done, I could copy Sindarin sentance structure, even if Sindarin has a valid copyright, without infringing; thereby allowing me to generate original works. ### The case of *Prelude to Axanar* There have long been Star Trek fan films, mostly (in my opinion) terrible. Evidently, Axanar was to be a fan film with a budget of over $1 million, some serious production values, support of Important Star Trek People like George Takei, and even some actors who had appeared in other Star Trek movies. Paramount, which had hitherto been relatively tolerant of fan films, sued for copyright infringement. Paramount had a [pretty strong case](https://www.washingtonpost.com/news/volokh-conspiracy/wp/2017/01/09/copyright-in-klingon/?noredirect=on&utm_term=.dd942aba40ab), since characters like Garth of Izar and fictional races like Vulcans and Klingons are pretty clearly copyright-able. Eventually, the [case was settled](https://en.wikipedia.org/wiki/Prelude_to_Axanar#Lawsuit) in 2017. However, in the course of the lawsuit, Paramount asserted a claim to control over the fictional languages. Sort of. This was probably never a claim that Paramount really wanted to make, but was just involved in the legal claptrap. The Language Creation Society (LCS) filed an [amicus brief](https://drive.google.com/file/d/0BzmetJxi-p0VM19nbUpyNXE0a28/view) stating that conlangs were not copyrightable, and the defendants (the producers of *Axanar*) [filed a motion](https://torrentfreak.com/images/lim.pdf) that also said in part that the Klingon language could not be copyrighted. The defendent's motion was accepted by the court, so the copyright issue over the constructed language was excluded; the LCS's amicus brief was then [rejected](https://drive.google.com/file/d/0BzmetJxi-p0VN0t5MWNPOTZ4SU0/view) by the court as not applicable. Ultimately, this case decided nothing. Paramount had a strong case with characters and races and organizations and probably wasn't willing to risk a negative opinion on constructed languages. If anyone is going to file a lawsuit to get open use of a constructed language, it won't be about Klingon since Paramount is a lot richer than the inventor of any other conlangs. But it is relevant that the judge was willing to accept the defendant's reasoning which referenced the same *Baker vs Selden* which provided the precedent with computer programming languages. # Conclusion There is no official court decision on whether the grammar and vocabulary of a constructed language, being utilitarian in nature, can be copyrighted. However, there is some good evidence and legal opinions that, in the US at least, such copyright laws would not apply. Of course someone has to test this in court. Maybe it could be you? If Tolkien's estate comes knocking, you could fire up a GoFundMe and appeal to all the language nerds out there. *Your Name vs Tolkien* would get its own Wikipedia page and article in the Harvard Law Review...you'd be famous! [Answer] You could also use an [extinct language](https://en.wikipedia.org/wiki/Extinct_language) that no one speaks anymore. There are hundreds [to choose from](https://en.wikipedia.org/wiki/Lists_of_extinct_languages). Being a real language removes any legal issues, gives you all kinds of real grammar and everyday words instead of just the ones that are needed for the story. And best of all, if your work becomes popular and people start learning it, you could be helping to raise a language from the dead. [Answer] Most conlangs are the work of one person. Whatever the legalities, it would be odd to borrow them for a new work. However, there are ongoing efforts in many conlanging communities (such as Reddit’s [/r/conlangs](https://reddit.com/r/conlangs)), to construct conlangs within the community, with no one owner, open for use by anyone. There are a couple of active projects on Reddit, and no doubt also a few elsewhere. [Answer] Taking the legal problems aside, another problem is to find a conlang that really satisfies your needs in terms of vocabulary and grammar available. Answers to [this question on conlang.se](https://conlang.stackexchange.com/questions/539/are-there-speech-communities-for-tolkiens-elvish-languages) suggest that the account of Tolkien's Elvish languages is too sparse to be really useful. Even for the *Lord of the Rings* films and the *Hobbit* films, new Elvish words were created by the linguist David Salo. So there are currently two options left: Design an Elvish language on your own or [let someone else create a conlang for you](https://conlang.stackexchange.com/questions/507/how-can-i-become-a-professional-conlang-designer). [Answer] ### Apparently not I have been searching and the only answers I have found are already mentioned in this [reddit-thread](https://www.reddit.com/r/conlangs/comments/1mwn9u/are_there_any_open_source_fantasy_languages/?st=jgexp6hp&sh=be61dd80). > > Quenya, Sindarin, and all other languages by J. R. R. Tolkien are copyrighted until January 1st, 2074. > > > Everything appears to be "copyrighted". Just a few might not be. I have not checked all the details of *[Láadan](https://de.wikipedia.org/wiki/L%C3%A1adan)* and *[Divinian](http://divinelanguage.webs.com/divinianthebook.htm)* yet, but I have not quickly found anything about those being copyrighted or not. Most authors do not go the full path of creating an entire language and those that do tend to copyright it. Can't really blame them, it's a huge effort. **EDIT**: To my knowledge you can not just copyright a language. You can copyright publications of any sort, but the a language is nothing you can publish or copy in that sense. However, using a fictional language of someone else (in copyrighted material) could probably get you in legal trouble anyway. Just like copying the entire storyline and scenario of The Hunger Games and changing all the names of people, locations, parties, technologies, etc. would probably get you into trouble. If there is a legal expert on this to clarify whether taking such a significant, recognisable part of copyrighted material and just using it for your own publications gets you into trouble, listen to them. But I definitely see a possibility of this getting you into trouble, so I would advise against it. **EDIT2:** User jeffronicus just found something and posted it as a comment, but since it is relevant I will add it here. > > Relevant Tolkien-related post by someone familiar with copyright law: "Know Your Rights: Copyright Law for the Creator of Fan Works," [theodoramichaels.com/articles/fan-fic.php](http://www.theodoramichaels.com/articles/fan-fic.php): "Cathleen Blackburn replied to me as follows: 'In relation to Quenya and other Elvish languages, the Tolkien Estate takes the position that these are copyright works and, accordingly, a licence is required for any uses of them which would otherwise amount to copyright infringement.'" It's unlikely a publishing house would take the risk. > > > [Answer] The question of copyright on synthetic languages is an interesting one, on one hand concepts and names aren't generally subject to copyright but on the other hand there is a reasonable argument that a constructed language as a whole is an original creative work and would seem to fall at least within the intent of copyright law. One possibility is to choose a real language find a systematic way to modify it for example by substituting certain vowels, consonants or word endings. This tends to happen naturally in language development anyway and so should work reasonably well. A good starting point is the Norther European language family of which Old English and Old Norse are members. In fact Tolkien was a professor of Anglo-Saxon and a lot of his constructed languages are at least inspired by this family. A good candidate is modern Icelandic as this is probably the closest to Old Norse which is still spoken so there are plenty of resources for it easily available. To me Icelandic sounds a bit smoother and more elf-like than say Norwegian and doesn't has the same pronounced up and down cadence. For example you could modify it by replacing the **k** with (soft) **c** the **tt** with **l** or **ll** and the leading **H** with **D** or **S** just to make it look a bit different on paper and mellow the pronunciation a bit. [Answer] **The first** thing that came to mind were constructed languages, the [wiki](https://en.wikipedia.org/wiki/Constructed_language) on it is a great thing to read. Suggested constructed languages to use: * [Esperanto](https://en.wikipedia.org/wiki/Esperanto) * [Occidental](https://en.wikipedia.org/wiki/Occidental_language) **The second** idea is languages from a different language group then the writers. As this is in English, use a Celtic language, or better yet, a [language isolate](https://en.wikipedia.org/wiki/Language_isolate). Suggested languages from different groups: * [Breton](https://en.wikipedia.org/wiki/Breton_language) (Celtic) * [Basque](https://en.wikipedia.org/wiki/Basque_language) (Isolate) * [Bangime](https://en.wikipedia.org/wiki/Bangime_language) (Isolate / [possible anti-language](https://en.wikipedia.org/wiki/Anti-language)) **Thirdly**, elvish uses a different script. That helps a lot with making it foreign to the reader. Now, the Bangime language does have different letters then the Latin (adapted) script used to write English. I would like to suggest to use at least a different font for your 'elvish' language. A variation to that, as unknown scripts are very hard to read, is to write your 'elvish' phoneticly. That way the reader gets a sense for how it sounds. --- As to copy rights, most (natural) languages do not have one on them. They are in the public domain. And other answers go into details on 'Tolkien elvish". ]

[Question] [ I've got a new invention which I think could revolutionize the transportation of people and goods: it's a teleport unit, which can transmit matter from one portal to another regardless of what is in between the portals. Unlike most teleports, though, it isn't instantaneous. It takes exactly as long as it would take the item being teleported to travel in a straight line between the portals, at the speed the item was introduced to the portal: if it is introduced at 60mph, and the exit portal is 60 miles away, it will appear an hour later, still traveling at 60mph. The item being teleported doesn't seem to experience the time, but just sort of skips over it - it's instantaneous from the traveler's point of view, just not the rest of the world. The problem is in the marketing of this. Obviously, I can't advertise it as being useful for getting to last minute business meetings: it'll take just as long as travelling in a straight line would, even if you don't experience that time. Testing has shown that people tend to feel a bit uncomfortable if they're travelling in a fast vehicle that goes through a portal where there is a jarring change of light/scenery, so I'm thinking of taking on the container shipping industry. My plan is simply to push containers through the portal, on rails, so the drivers never need to go through either way. I can't help feeling I've overlooked something though... * It requires a portal at each end, but doesn't draw power beyond what a reasonable electric socket could provide (it doesn't need a power station to run, but can't be set up off-grid really) - this is a continuous draw, so needs to be applied for the full period of transportation, to both ends. It doesn't vary power consumption based on whether anything is going through the portal or not though, nor on the mass of the transported items. * Haven't found any particular limit to how big the portals can be, but things being sent need to fit through both ends (well, technically not... But only the bits that do get transported...) * Portals can't be moved while active - offline portals can be moved and reconnected, but anything sent to them while they are offline is lost. They can technically send or receive items, but they will come out scrambled and possibly incomplete. To avoid this, both portals should be stationary relative to a large gravitational pull - all testing has been using the Earth as the anchor, since I don't have any access to space. Don't see any reason why it couldn't be relative to a star or other planet though. Probably makes them less useful for interplanetary travel... * If something is part way through a portal and stops moving, you get part of it sticking out each end, once the transmitted part reaches the destination. Not sure what happens if you then push from both ends... It seems unlikely to be good. * If the power fails or is cut off, anything in the portal (e.g. has entered at one end and not yet exited from the other) is lost. Not sure where it goes - haven't found anything that suffered this fate yet. Stuff pushed directly into to an offline portal just goes through the space the portal encloses (like an open door). Stuff pushed into a portal where the other end is offline is lost. * They are bidirectional. Can put stuff in either end, and it comes out the other end, assuming the power is kept on to both portals at all times. What's the best way to utilise this invention to get rich? [Answer] Some uses that came to my mind: * Use it as garbage disposal. Just push it to an offline portal. Especially useful for radioactive nuclear waste for example. * Use it as a time travel device to the future. Let's say you want to travel 100 years to the future, then just calculate how slow you would need to move into the portal so you end up at the other side 100 years later. Very useful for terminally ill patients that hope that a cure exists in the far future. Downside is that it needs to be powered all this time. * reduce infrastructure of utilities. electricity cables, internet cables, sewer pipes, water pipes, you name it. all these things can be connected from your house directly to the supplier through a portal. [Answer] ## Perpetum mobile Other answers aside, you could for example modify a hydroelectric power plant by placing an "input" portal below the turbines and an "output" portal above. Hey, infinite energy! [Answer] **You have solved food preservation** Who needs a clunky old refrigerator that only *slows* the rotting and decay of fresh food? *Just make it so your food doesn't experience time!* Meet the new tele-preserver, which has the input and output portals side-by-side, and which constantly cycles the food into the portal unless the door is open. Your food is still reasonably accessible, but only ages for the fraction of the time that it's not in the portal, which could be made arbitrarily small (at the cost of accessibility). Fresh meat and produce can now keep for years, without any added preservatives! [Answer] ## Congratulations! You just made container ships obsolete! Container ship is the tool of transport when talking about bulk transport: [](https://i.stack.imgur.com/7CmgS.jpg) Even if you ship goods at relatively slow speed of railway transport, you: * Actually made shipping goods faster, because you save time on unloading and re-loading cargo from and to ship * Made **ton** of savings on fuel, because if the portal runs "from the power socket" it is fraction of shipping cost * Also, you made shipping of goods ultra-safe and not reliant on weather (related question: What happens if I unplug the portal in the middle of transportation?) Being at your place, I would contact some world-wide shipping company. They will pay you anything you ask, really [Answer] Depending just how fast one can enter the portal you have just made every other form of transport obsolete for speed of transit. If one were to set up two portals in vacuum chambers and run a sealed bullet train between them then you could go from say London to New York at a thousand odd kilometers an hour ground speed, that's faster than Concord ever went, and with very little infrastructure since you only need a few kilometres of track for acceleration and deceleration rather than for the whole trip. Furthermore you save more and more trip time the farther you're travelling since there is nothing suggesting that one cannot in fact point a portal in New Zealand at another in Spain and transfer goods directly. Trips can now be made through the planet potentially cutting tens of thousands kilometres of surface travel out of the trip. [Answer] If it uses the amount of power that one can draw from a household socket, the "no time experienced" part is almost as important as the "transport over distance" part. If you point the ends of two of these portals at each other, you can create a loop that holds for as long as each portal is drawing power. Any object introduced into the system enters suspended animation. You can drop the item out of suspended animation by cutting the power to one of the portals. You just solved the deep space hypersleep problem. You also have replaced certain types of refrigeration / freezing. There are also interesting things that could be done here in the criminal justice space. [Answer] On the "black market", it could be used to bypass customs, or immigration control, as a way of delivering illegal drugs or other controlled items. Alternatively, militaries and similar organisations could use it to transport large numbers of troops, weapons and resources, e.g. across neutral or hostile territories without having to worry about treaties or negotiating access, or being detected, etc. Also for humanitarian problems - people trapped in certain situations could escape (e.g. if they are under siege, or in a cave (depending on the portability of the device), etc.) or have important supplies delivered to them. [Answer] # Goods You're thinking people, but moving people around is low volume and high cost relative to the profits to be made from moving goods. The railway companies have always wanted to stop transporting people for exactly this reason, even though moving people is the iconic purpose of railways. You've added an avenue primarily for the movement of perishable, highly delicate goods, or even live animals. You're not going to be damaging or aging things in transit if they don't experience time on the way. Don't worry about speed, modern container ships are [slower than the old sailing ships](https://www.theguardian.com/environment/2010/jul/25/slow-ships-cut-greenhouse-emissions). Your movement costs also seem to be considerably lower than normal shipping, what you've probably forgotten is TANSTAAFL, and this looks a lot like a free lunch. --- **Less profitable uses:** There are some interesting considerations in emergency response where an ambulance becomes a mobile portal, shove the patient in on pickup and there's no deterioration of the condition on the way to a hospital anywhere in the world. [Answer] The fact that the transported person does not experience time is a huge boon for medicine. Put one portal in every ambulance, even if you need an extended electrical plug to the grid. Emergency victims will not bleed out while on their way to the hospital. Hospital patients could also be sent on multiple round trips to faraway places to gain time while, say, lab tests come back, or a rare medicine is sent in. Heck, put hard cases on that dynamic stasis while their doctor goes home to sleep. No more risky handovers. [Answer] **SPACE!** If we can get a portal up and running on any moon/planet/asteroid we want, we just saved trillions of dollars of effort to get large masses to those planets. Even if it takes months to get there, it'd be worth it purely for the fuel savings. Plus, if we send astronauts, we don't have to carry food for the journey. [Answer] Instead of moving normal goods consider moving liquids, which can be pressurized, instead of building millions of miles of pipeline to move **oil and gas**, you just need a portal at production and another and distribution. as a bonus you eliminate 90% of spills. this does not jut work for petroleum, consider how much time and energy we put into moving **water** around, pumping large amounts of water uphill will be a thing of the past. Speaking of uphill, **SPACE** Put one portal in geostationary orbit, and you now have a space elevator without the need for a tether. getting to space just got cheaper than getting to cincinnati. Design it right and you can literally fall into orbit. [Answer] Extremely efficient transportation. The largest energy hog for say a train is keeping it going fast while air resistance is in play. Further the extensive rail and road network takes up a ton of materials and energy to build and maintain. The easiest method to gain millions if not trillions is the space business. You would cut the energy requirements to get anything into space to less than 1/1.000.000th, and the lack of needing to survive the acceleration allows for cheap satellite and space object production. Even better: build a giant hole, suck the air out and drop your space object in it, it'll pass through the earth and be collected in space with practically zero energy cost, you could even generate energy with the objects fall!!! (just to be clear, the hole would have a teleporter at the bottom and not go through the entire earth). Assuming the teleporters need to be straight opposite of each other (and assuming that movement of the planet, continental drift and solar system doesn't matter) your second best bet is transportation through the ground. For small stations you build a track that can be turned some degrees up, down left and right so you can aim it at different stations, then you launch the train-like object. Build a few to catch and release multiple trains at a time. For large international stations You build a subterranean station with a giant sphere. The sphere has enough room to accelerate a train-like object. The train is boarded, placed in the sphere, then turns the entire track to aim it. You control the lighting and surroundings so its not as inconvenient for humans. A long enough track and sucking air out allows you to reach 7000km/h, although this is probably too large to work for a real busy airport-like area as it would need dozens of massive spheres to work so "Just" going a few hundred kilometers per hour and traveling in the straightest line ever conceived should work. As an alternative you could build the tracks in series, so a train could come rushing through multiple tracks in a row to its destination allowing it to accelerate and decelerate each time it reaches a station until its destination is reached. As an alternative for giant spheres you could use multiple substations that have a predetermined exit point. This is useful in the event that both sides of a portal need to remain active while something is in transit. You don't want your few tracks to be constantly empty and in use. So you have one "common" station that can be aimed at half a dozen substations. The common station is where the train is taken off the main track to board/exit. The train is then launched through a portal at one of the substations, there it will continue it's acceleration and then be send to it's destination without the main track being in use all the time. A big advantage is that while the track is in use to send, it could potentially also be used to receive without either train colliding with eachother. This would make these trains feel more like a rollercoaster: You are launched in a straight line, reach the substation that has a curved track that will point the train at it's destination while it accelerates. There could be a dozen rails going to the same destination next to each other each with their own portal. Even with portals that have to be aimed at each other you still can create perpetuum mobilea, but you have to be smarter about it. For example you can launch something at 10km/h (or any speed you like) into space (or just a really high tower) where the mass is caught, then the mass takes an elevator ride down using its mass to push the elevator down while a lightweight other elevator is pushed up again (similar to most space elevator designs), generating electricity to launch the next object. We are talking about using multi-ton masses here of course to generate a good amount. Additional bonus advantages: Faster internet. Currently we lose a ton of time sending information through cables to substations and servers around the world to finally arrive at the computer/server you want. This requires miles and miles of cables and information magic to streamline it. But if you have portals you can streamline this process a lot more. Here's Lifi: <https://en.wikipedia.org/wiki/Li-Fi>. What you do is that each large server across the world is connected to the others not by cable, but by portals. You could try using cables through the portals but they would either have to be kilometers long or you would have to wait for the cable to reach the other end each time the connection was broken for some reason, so Lifi seems a safer bet. You put industrial-scale Lifi at the portal, and use it to communicate with the other server. This is the straightest and fastest connection you can make, as it would allow the server in DC to communicated directly to a large hub in Australia, going the shortest route through the earth without any intervening hubs or subrouters or whatever in the way. Considering that the Earth is 12.742km in diameter the maximum latency between any two main servers in the world would be reduced to 41ms. This would make playing a game against anyone anywhere in the world possible with maximum latency as large as that you would currently find playing on the same continent. To speed it up even more you could perhaps allow people to set up a router that can be calibrated to link directly to a portal near the main server... This would mean that people could realistically build one giant server on the world, have every single person aim a portal at it for internet and the maximum latency you would experience would be 82ms (plus a little for conversion at your PC, the server and the other PC). And this is assuming you are at the exact opposite of the planet compared to the server and the one you are talking to is sitting next to you meaning the signal needs to travel through the earth and then back through the earth. I mean holy crap that would be some awesome internet right? The biggest hurdle would be building a small portal for each individual connection, or somehow allowing multiple connections to use one portal and let the broad spectrum of light be the way you keep the signals seperated! I would expect it likely that in this scenario each continent would build it's own super-server for the internet. [Answer] You would no longer need those long distance power transmission lines, purchasing huge swaths of land, and reducing the scenic value of the landscape. Set up a portal at the power generating station. Set up a portal at the receiving end. Pass one end of the power line into the portal ... and stop when it is halfway in. Wait for the power line to come out the far end ... and stop. Connect generating station and loads to power lines. Turn on the power. Of course, this assumes electricity will "jump" through the portal along the wire from the wire molecule just before the portal to the wire molecule just after the portal. Fortunately, electricity travels near the speed of light, so it would pass rapidly through the portal. You need a closed loop for electricity to flow, and it isn't clear the electricity can "jump" backwards along a second conductor through the portal in the reverse direction, but you could just make a second pair of portals for the reverse direction conductor, although you'd be restricted to DC power transmission. If current can flow both ways, you could do AC power transmission with just need one portal pair. Along a similar vein, oil and gas pipelines would benefit immensely! Similar land purchase savings, scenic improvement. No fights about whether or not a pipeline can be built along a swath of land. No pipeline leaks damaging wilderness preserves. Cost of inspecting the entire length of the pipeline boils down to a couple of meters before and after the portal. --- Tiny Hadron Collider (THC). Instead of needing a 27 km long ring, you could build collider in the space between two portals. Fire a particle into one portal, it comes out the other portal at the same speed, is accelerated by super conducting magnets, enters the portal, comes back out, is further accelerated. Instead of needing decades and costing billions to build, along with land purchase encumbrances, you could build one ... in one building? in a school classroom? on a table top? [Answer] This invention could be used at intersections to make them safer and more efficient. We already have power to many major intersections to run stoplights, so we could instead power a portal on either end of the intersection to prevent needing to slow down or stop at the lights. There would probably need to be separate portals for the turn lanes (and a safety precaution to ensure that those turning don't spawn into a car going straight), however. [Answer] > > What's the best way to utilise this invention to get rich? > > > ### Hibernation "*The item being teleported doesn't seem to experience the time, but just sort of skips over it - it's instantaneous from the traveler's point of view*". So, you want a one-way trip to the future? How many years do you want to jump? Just enter one portal on a vehicle which moves 1cm per year and you'll be out of the portal 1m apart 100 years after! without getting old! That's amazing! You can sell this service for sick people which current technology cannot cure but maybe future technology can. You can always re-enter the portal for another 100 years if the technology is not advanced enough yet. ### Space colonization Send to another planet a probe at whatever speed you're able to, and make it build an exit portal at the destination point, then send humans or machinery there, it wouldn't matter how long they take to get there, they'll still be young, strong and ready to colonise the planet. [Answer] ## Guaranteed Humane Execution Since anything in transit between two portals is lost when one portal loses power, you have a way to guarantee successful, painless execution, with the added bonus of body disposal. No one can argue that it's inhumane, so that problem with executing criminals is entirely eliminated. Botched executions would amount to the portal failing before entry, which has no nasty side-effects. And a last-second stay of execution would be possible even after the executee enters the portal...just don't turn it off, execution stopped. I mean, there'll be hippies complaining that "lost" isn't the same as "ceasing to exist" or "instant atomization". They'll have crazy theories that there's an alternate dimension or whatever where the "lost" stuff goes. But that's just crazy. [Answer] ## Time Travel for Terminally Ill Forget cryogenic freezing, this is literal Time Travel, albeit in only a single direction. And yeah, maybe the process is slightly unpleasant, the disorientation do to differing locals can be mitigated as mentioned in other answers. However you coudl send folks through at a slow speed and over a long distance... Got cancer, and only 3 months to live? Bampf, take a trip, very slowly, over a moderate length, come out a year later. If science hasn't progressed enough to cure you, back in for another year. Repeat until your malady is solvable. ## Bonus Time Travel uses You could also send produce into the future. Everything is now in season year round, transportation is minimal cost, and spoilage is largely not a factor anymore. ## Perpetual Motion/energy Production Finally, with the proposed energy expenditure it's fairly easy to not just get free energy, but create energy. In fact, with a little ingenuity you could embed a smaller version of one of these inside each machine, that would provide enough energy not just for itself but for the machine it's inside. ## Orbital Correction Depending on how you place them around your planet, and when you use them, you'll have a small effect on the momentum and spin of your planet. If they're equally distributed the effect will mostly cancel out, but if you positioned your self-powered portals (see point 3 above) strategically around the planet, and powered them intentionally with calculated timing you could change the orbital speed of the planet, as well as shift the orbit. We're talking very slow change here but it might be enough to compensate for global warming/ice ages by shifting the planet's orbit slightly ... Don't forget to shift any moon(s) your planet has as well. Additionally you could make the daily rotation match between all your planets which would aid interplanetary coordination. -Hat tip to @Perkins [Answer] The use of electrical or optical traces through micro portals would allow for reliable long distance secure communications. It could replace all EM based transmission mediums (cable, radio, laser, etc). This application alone would yield you more money than you could spend in a 100 lifetimes. [Answer] This might even be better than traditional teleportation. Because with the asymmetrical passing of time, you can improve and/or engineer... **Preservation** Put your leftovers in one end and give them a small tap. They'll stay warm and fresh for hours! Shipping in seafood from the coast? It'll be as tasty as if it were caught an hour ago! **Time-based security** Not only does the new safe at the bank only open once a day, but it's only in our physical world once a day! No cracking this one! **Medicine** No need to rush to the hospital. Just check the next available appointment and send them in with the appropriate speed! Patient needs a kidney in 24 hours? They now have all the time in the world! **Time travel** If you're willing to take the risk of a power outage, just casually stroll inside and exit in about three years. Not far enough? Just turn around and go back in! **Planck-definition audio and video** Light travels too\* and of course so does sound, so just put both ends behind a simple glass barrier with little holes in it to let sound out! You'll need to power it off to change "camera" angles but this would be perfect for surveillance. \*Sort of [Answer] Interplanetary and interstellar travel. Sure it might be slow for the real world but it's fast for the travellers and it's far safer than actual space travel. Once established, you can mine H3 from the moon to solve the energy crisis or metals from Mars. Dump toxic/nuclear waste on Pluto. Dump a gate in space and you can build space stations quickly and cheaply. The uses are endless. [Answer] I could see this replacing parcel service. Think about each household having a delivery portal assigned an address. The portal outputs to a cushioned box the size of a few large packages. The local post office has input portals for each address (like PO boxes, but a bit bigger). The postal person just shoves your stuff into it and presto... you have mail. Each local post office could have an input portal from the distribution hub that is the larger-scale version of household delivery. Upstream from that it may become complicated, but... at least for last-leg delivery, it could put Amazon's drone delivery to shame. If the input box at your address was padded enough, the packages could even be sent at fairly high speeds (slower for fragile packages). A green light red light indicator could be used on the input side to show that it's "safe" for another parcel to go through if a slow-moving fragile parcel was already on it's way. Blast bills through using a modified ball chute or pitching machine. [Answer] From another point of view, you can make good disapear temporarly! Nowadays, on some industries, like the automotive industry, stocks don't exist because they have costs, everything arrives "just in time". With your techonology there would be a revolution in logistics, either by making products appear directly on productions lines on the other side of the world and making stocks possible again. [Answer] Those portals are still very great tools for: * Tunneling through enemy territory (Think of the location of West Berlin during the cold war and the [Berlin Blockade](https://en.wikipedia.org/wiki/Berlin_Blockade)). * Avoiding customs stations except there is a customs' office at each portal. When you can make really many of them, customs and toll will become meaningless because they are so easily circumvented. * No traffic jam * There is no need to spend money for walls on borders because they are easily by-passed [Answer] Here's an interesting side project you can setup that has the option to be extremely profitable as an adjunct to the basic teleportation system. Extremely accurate speed devices. These are small vehicles, possibly with extremely large motive force, think the land bound equivalent of a tug boat. The reason for these is that with the correct computation of distance and speed, you can time the moment of delivery as accurately as you want, based on setting entrance speed as accurately as you can. The longer the distance, the greater accuracy of speed needed to get the same temporal maximum error. This has the possibility of becoming known as the "Dgnuff uncertainty principle", which states that "The product of distance and absolute temporal error margin is inversely proportional to the accuracy of the entrance speed." [Answer] * Efficient and clean **waste managment**, as opposed to landfill. Especially useful for getting rid of dangeorous waste (medical, radioactive, toxic...) Just make portal endpoints far enough and slowly push trash in. Then, before trash starts coming out, turn off the portals. Typically human :-( * Revive a **space program**. You just need to invest in one regular successful launch to get one portal on moon. After that, you have a safe and cheap way to get stuff on moon, where you can then move your factories, space vehicles etc. and get much easier and cheaper access to space from there (lower gravity pool). From there human race can expand and avoid extinction. And I'd buy into vacation on Mars! [Answer] As far as "normal" applications would go: Worldwide shipping (especially for heavy goods)! If you go exactly from one side of the earth to another, the portals would be on par with planes even if you send the goods far slower (and if you build a high speed train through it you would be much faster) than planes (that go around the earth) all while saving ENORMOUS amounts of fuel. Also for the more shady side of this: smuggling. These of course would be far less profitable than the more "cheating" proposals of other answers. [Well unless you smuggle tons of cocaine directly from the plantation to major US cities] [Answer] Wait? Humans can survive this portal but it takes time to end up half-sticking-out the other end. Tell me the physical laws by which this works and I'll tell you how to build a backwards time machine. It's immediately obvious something is up with this because of the delayed response with a push or pull while half-way through but the person doesn't die of being bisected ergo blood flow is working normally. [Answer] *New "Portal Sleep Pod Commuter and Travel Suites" Industry* Within a practical distance, people will be able to live and commute much farther distances between work and play. If they choose to, they can kiss their loved ones good night and head off to work at the same time. They'll pack a bag, go to the local portal sleep pod (PSP) suites and swipe their paid ticket or membership badge. They stow their bag and hop into a nice comfy bed/portal pod, set their alarm, and snuggle in for a good sleep. They wake up when their alarm goes off in whatever location programmed in for that trip, be it business or pleasure. Because they were asleep, they are fine with feeling no time had passed at all, and they weren't aware of any uncomfortable scenery change. The badge links them to a preprogrammed destination and preset timing that is personalized for how long it takes them to fall asleep. The beds are on a track that can simulate motion so as they fall asleep they won't notice the actual movement to and through the portal. Light sleepers will just use the usual sleep aids. The PSP suites wil come in different varieties and brands according to budget and style preferences, and a customer's "stay" will include access to a shower room and toiletry areas, gym equipment, and complimentary breakfast or lunch buffets or other dining options. [Answer] You've invented a wormhole which will allow you to send information to the other side of the planet faster than all other people? Folks have literally made billions of dollars in the stock market by being able to predict fluctuations or balance two markets a fraction of a second faster than the 'other guy'. You don't even need to worry yourself with messy predictions... you're shooting what's actually happening in the Asian market to the States faster than any one else (they have repeaters (eg. delay) and a longer path to transverse, through medium which isn't going at the speed of light.) Your automated buy/sell processes kick a clock cycle earlier than theirs, and you're rich. So get your low latency, free-space optics transceivers set up and start taking it to the Man! [Answer] Very cheap storage. "Don't need that sofa for a few years but don't want to get rid of it? We'll send it to Mars and back and you don't have to have a storage shed!" ]

[Question] [ I've been trying to write a book for years about a post-apocalyptic society entirely run by children, in which all of the adults died off and the children have to figure out how to survive and, eventually, rebuild. However, I cannot figure out a plausible way for all of the adults to have been killed off. Maybe by some sort of sickness? I'm not sure how I'd just kill off adults, though. Any ideas on what might plausibly kill off the entire adult population? These people can (and must, for the story to work) grow to be older than 18. The thing can move on or still exist, it doesn't really matter as long as it doesn't kill off the remaining children in mass quantities. [Answer] My line of thinking is this: If you want to kill everyone over 18, it should ideally be linked to something that only those older than 18 are able to do. Computers are getting smaller, and wearables are becoming more fashionable, it's not unfeasible that within a few decades we'll have [implants in our brains for interfacing with computers](http://waitbutwhy.com/2017/04/neuralink.html). As with all technology, this will spread to the point where (almost) everyone will want one, and it could be made compulsory by the governments of the world at some point (optional). Obviously we won't want to put chips in our kids brains until they're fully developed, so when they inevitably malfunction, killing everyone, only the kids will remain. This could encourage a sort of taboo, surrounding technology, which would explain why even those who grow into adults don't instantly start using all the tech that's still laying around - there might even be a concerted effort to get rid of it all. This could open up some new narratives also, with arguments over the new anti-technology practices that are going around, and inquisition style bands of kids, roaming and casting judgement on anyone accused of using tech. [Answer] There's no clear dividing line between a person aged 17 and one aged 18. However, before puberty, the human body has significant differences in the release of hormones. The primary hormone which stimulates puberty is the Gonadotropin-releasing hormone. GnRH is a neuro-hormone and stimulates certain behaviour patterns, the hormone influences a person's physiology. It is therefore not unreasonable that a certain compound for which GnRH acts as a catalyst can cause dangerous and even deadly effects on only those with a significant amount of GnRH (in short, everyone who is going through puberty would die first, and then all those who already have done that). Another possibility is a microbe which binds with one of these hormones as a way of infecting its host. This could kill off everyone over 13 (except for those who present with Isolated gonadotropin-releasing hormone deficiency). Four years later, the 13 year olds will be 17. [Answer] ## Real-World Immunological Changes Occur At The End Of Puberty The [Thymus](https://en.wikipedia.org/wiki/Thymus#Development) is a lymphoid immune system organ that grows during childhood up through the end of puberty, then begins to shrink. It's size and strength while young results in a much larger quantity of T-Cells, which make the bodies of people in this age range more capable of fighting certain types of foreign bodies. This is one of the reasons why Chicken Pox is mostly just inconvenient while younger, but can be deadly while older. You could have an unknown viral disease that everyone has, but remains latent (walking dead style) because the immune system is strong enough to keep it at bay in the vital areas of the body. As they age and the Thymus begins to shrink and weaken, the virus eventually reaches the point where the body is no longer able to keep it in check, and from then on it begins to rapidly spread, killing the host. Puberty typically ends around 17-18 for both boys and girls, although there is some variance, and the complete range of developmental effects can still go on for longer (early 20's). Nonetheless, you can interpret the effects on the thymus (and at what point it becomes weak enough) to suit your needs for the story. With the added specification that the children must be able to grow into adults, just have the virus be a one time thing rather than a latent one, and children's bodies are able to fully defeat it instead of just beating it back, so that the virus dies out completely once all the adults are dead. [Answer] This was the plot of a Turkish science fiction novel I read as a child. I cannot recall the name of it, though. In that novel, the superpowers develop the same bioweapon and secretly start to vaccinate their children. Adults are not vaccinated for purposes of maintaining secrecy. When the bioweapons are accidentally released, only children from the two superpowers survive. The author may have been Gülten Dayıoğlu but I am not sure. [Answer] (UPDATE: [Found a source!](https://www.scientificamerican.com/article/bring-science-home-high-frequency-hearing/)) As humans age, our range of hearing changes slightly and it gets harder for us to hear high-frequency sounds. As a result, there are certain tones (between about 16 and 20kHz) that can only be heard by teenagers - these have been used to create special "[mosquito alarms](https://en.wikipedia.org/wiki/The_Mosquito)" to deter teenage criminals and loiterers, as well as "Teen Buzz" ringtones that can't be heard by teachers. This change in hearing range - known as presbycusis - is the only way I can immediately think of that you can reliably distinguish between children and adults, in order to kill the latter while sparing the former. Either: * A tone that only adults can hear, and that kills them, or; * A tone that only children can hear, and that somehow spares them from whatever kills all the adults Since you've stated you want the surviving children to be able to grow up, the tone should only play once, audible across the planet, for as long as it takes for all adults to die. After that, it never plays again. [Answer] You could create a unique deadly strand of Mononucleosis. Children only show symptoms of the common cold where as adults can suffer all sorts of health problems. > > Infectious mononucleosis (IM), also known as mono, kissing disease, or > glandular fever, is an infection commonly caused by the Epstein–Barr > virus (EBV).[2] **Most people are infected by the virus as children, > when the disease produces little or no symptoms. In young adults, the > disease often results in fever, sore throat, enlarged lymph nodes in > the neck, and tiredness**. Most people get better in two to four weeks; > however, feeling tired may last for months. The liver or spleen may > also become swollen.[3] In less than one percent of cases splenic > rupture may occur.[6] > > > Infectious mononucleosis is usually caused by Epstein–Barr virus > (EBV), also known as human herpesvirus 4, which is a member of the > herpes virus family. A few other viruses may also cause the > disease.[3] It is primarily spread through saliva but can rarely be > spread through semen or blood. Spread may occur by objects such as > drinking glasses or toothbrushes. **Those who are infected can spread > the disease weeks before symptoms develop**.[2] > > > From Wiki [Answer] Two pandemics, nineteen or twenty years apart. The first epidemic is a very mild (or even helpful!), easily transmissible disease that remains contagious for an extended period of time. (But it is not contagious forever, and infants who have the disease are not contagious.) After a year or two, everyone on the planet has antibodies to it, and it burns itself out. The second epidemic is fatal to people who have antibodies to the first disease, but completely asymptomatic to people who do not. It remains contagious indefinitely. In this scenario, even if there are surviving adults, they will completely segregate themselves from the children. And they will continue to segregate themselves indefinitely, because any contact with young people is likely to kill the older generation. [Answer] # In an overpopulated world, deep in the future, life expectancy was too damn high. The solution? Life defining chips inserted into every human being on Earth. Yup. A chip, powered by the cloud, that defines when you die. That is until Jonathan (a humanist, wiz-kid, computer hacker) corrupted the system entirely. Although things didn't quite go to plan... a built-in fail safe kicked in and automatically wiped every human over the age of 18 years. Only now can those left over be free. It is up to this younger generation to run the Earth in a peaceful, self-sustaining manner. Will they succeed? [Answer] There are plenty of existing literary examples of this. In fact there's a trope for it! <http://tvtropes.org/pmwiki/pmwiki.php/Main/TeenageWasteland> In my experience this is produced by one of two reasons: # Disease A disease that targets adults. (e.g. [Only Fatal to Adults](http://tvtropes.org/pmwiki/pmwiki.php/Main/OnlyFatalToAdults "TVTropes: Only Fatal to Adults")) Biologically speaking, it could be something that triggers with the onset of puberty. If it's a virus, it could easily have infected the entire population. # Population Control Similarly, it could also be a form of population control as in According to TvTropes though, there are more variations: "*A society where the old nominally still hold power, but groups of youths have become too powerful to be truly controlled. (e.g. A Clockwork Orange).*" [Answer] **A virus that cuts off [Telomeres](https://en.wikipedia.org/wiki/Telomere) that are too short.** ([Repost](https://worldbuilding.stackexchange.com/questions/25074/killing-all-adult-people/25079#25079) from [duplicate question that got closed](https://worldbuilding.stackexchange.com/questions/25074/killing-all-adult-people)) To quote Wikipedia: "A telomere is a region of repetitive nucleotide sequences at each end of a chromatid, which protects the end of the chromosome from deterioration or from fusion with neighboring chromosomes. [...] For vertebrates, the sequence of nucleotides in telomeres is TTAGGG. This sequence of TTAGGG is repeated approximately 2,500 times in humans." Very roughly speaking: when cells replicate, the telomeres are shortened. This means that in young organisms, telomeres are long, and in older ones they are shorter. So... assume a virus - like a common flu virus - that has been mutated and targets cells with too short telomeres and simply cuts them off. Cell replication will be shot to hell and your chromosomes in each cell afflicted by the virus will be a jumble; the cells die. Once it hits it will probably be like a severe hemorrhagic fever (like Ebola or Lassa). If your telomers are long enough, you are not afflicted at all, your body adopts normal immunity to the virus and defeats it. Weaknesses in this: individual variation, individual immunity. There cannot be a hard limit that says "Until 18 years, 0 months, 0 days you'll be fine... above that - one day later - it is 100% mortality". But allowing some fuzziness in the outcome - such as a few kids die and a few adults survive - this could perhaps be sufficiently credible. To increase the credibility and avoid nosey questions - especially since cells replicate at wildly different rates in the body - you can have the virus target a specific organ, like the brain (compare to the movie [Contagion](https://en.wikipedia.org/wiki/Contagion_(film))) or the heart. [Answer] Rather than a sickness, you could go for nanotechnology. The apocalypse is the release of nanobots which are programmed to infect and kill adults and use some of their component materials to replicate and spread. The best option which occurs to me for discriminating by age which is tunable to the age which suits the story is to look at telomere length decay. It may not be quite accurate enough for biologists, but it should be good enough for a general audience. That leaves the question of why someone would develop these nanobots. You may already have some ideas. Off the top of my head, there is active research into reversing telemere decay in order to live forever. The billionaires who develop this treatment may wish to dispose of other adults in order to more easily shape society and rule either openly or from the shadows. Whether they survive as planned or not is up to you... [Answer] One of the nice things about this scenario is you don't have to explain very much about why or how. If you cover what happened from an in-universe point of view, there isn't going to be much detail - none of the survivors will be equipped to understand what happened on anything but a very superficial level. I can think of two examples of this approach which I really enjoyed. [The Girl Who Owned a City](https://en.m.wikipedia.org/wiki/The_Girl_Who_Owned_a_City) took the viral approach, killing everyone older than 12. The protagonist, Lisa Nelson, is far too preoccupied with the business of surviving and caring for first her younger brother, and later her citizens, to spend much time pondering how everyone died. [A Tunnel in the Sky](https://en.m.wikipedia.org/wiki/Tunnel_in_the_Sky) took a slightly different tack, the adults weren't dead, the children were stranded. It's the same idea, in that the children have no means of determining what went wrong. They have no access to the relevant equipment, nor the expertise to use it if they had. As long as it's internally consistent, lack of information doesn't have to be a bad thing. It really falls apart if there's someone who really should know what happens, so be careful of that pitfall. [Answer] The [1918 World Flu pandemic](https://en.wikipedia.org/wiki/1918_flu_pandemic#Patterns_of_fatality) did almost exactly what you are asking for. > > An unusual feature of this pandemic was that it mostly killed young > adults. In 1918–1919, 99% of pandemic influenza deaths in the US > occurred in people under 65, and nearly half in young adults 20 to 40 > years old. In 1920 the mortality rate among people under 65 had > decreased six-fold to half the mortality rate of people over 65, but > still 92% of deaths occurred in people under 65. > > > But why would it kill young, healthy people, and not babies and the elderly? > > Modern analysis has shown the virus to be particularly deadly because it triggers a [cytokine storm](https://en.wikipedia.org/wiki/Cytokine_storm), which ravages the stronger immune system of young adults. > > > People without strong immune systems didn't have as strong a response, and thereby avoided the cytokine storm. [Answer] ## Failed "experiments to prolong life" This question reminds me of an old *Star Trek: The Original Series* episode named *Miri*: > > The Enterprise receives an old style SOS signal and finds on arrival a > planet that is virtually identical to Earth. Kirk, Spock, McCoy and > Yeoman Rand beam down to the planet only to find that it is inhabited > solely by children. Kirk befriends one of the older children, Miri, > but they soon learn that experiments to prolong life killed all of the > adults and that the children will also die when they reach puberty. > They also learn that the children are in fact, very old. Soon, the > landing party contracts the virus and has seven days to find a cure. > > > [Star Trek Miri (TV Episode 1966) - IMDb](http://www.imdb.com/title/tt0394905/) [Answer] Great ideas! Pretty heavy on diseases and biological explanations, so how about a few that are different? 1. A society chooses a handful of children -- perhaps children of powerful politicians, athletes, scientists, etc -- to protect from a massive war or alien onslaught. Perhaps they are accompanied by some adults as they head to the safe place but the adults end up dying in a rear-guard action to save the kids. The safe place might be extremely small and deep underground, or could involve being launched into space in a ship that will take several years to get back to earth. 2. An alien invasion where the aliens kill anyone who resists, then they take all adults off-world for slave labor. The aliens view humans as we might view wild animals, so they leave the young ones and expect that if they come by in a few centuries they'll be able to harvest a new crop of slaves. (Having decapitated the earth's scientific apparatus, the survivors will fall back into the stone age fairly rapidly, though with lots of strange and failing technology around.) 3. An alien invasion where the aliens like to eat humans, but only *ripe* humans. 4. OK, one last medical thing: some new manufacturing process releases a ton of nanoparticles into the atmosphere and these particles are extremely toxic and kill most everyone whose cells have aged past a certain point. Younger children have less-aged cells and are able to withstand the cellular damage that the rest of the population cannot. This wouldn't precisely be a 17-18 cutoff, but might work down to what we view as the minimal viable age of self-survival and then the story begins however many years later such that the oldest survivors are 18. [Answer] There's actually a book series that deals with exactly this scenario called "The Fire-Us Trilogy" and starts with The Kindling. It deals with a younger group of kids after a virus (the Fire-Us, as the characters call it) wipes out all the adults, and does a nice mash-up of Fallout and Lord of the Flies. The actual mechanism of the virus is kind of a spoiler, but if I recall correctly, > > it has to do with the amount of sex hormones in the body. The higher your levels of Testosterone and Estrogen, the more likely you were to be affected and later die from the virus. This meant that children who have relatively lower levels of testosterone and estrogen were unaffected while teens and adults were decimated. > > > [Answer] There really isn't a great biological trigger - puberty is too young, end of puberty a bit too high (some changes in some people lasting into the 20s, not ideal if 18 *has* to be the cutoff - not to mention some medical conditions might apply). But, you might find environmental triggers. So, what do adults do that under-18s don't? ... well, nothing. All the age-related activities are restrictions, and therefore optional, and adults who did opt out will survive, skewing your population. On the other hand, what do under-18s do that adult's don't? Hah - maybe school works. If school is compulsory (like in our society), then 18 would be about the age of graduation. I recall we had a daily fluoride rinse program in our school - not strictly relevant, but there may be some other health-based program running at the right time that kids had to attend, that adults mostly were not bothering with. Maybe vitamins? Some kind of exposure from school buildings or chemistry lessons? Something that happened when the whole apocalypse got started - like barricading themselves in and avoiding the whatever? It doesn't have to be much, just enough to make it survivable. Of course, this wouldn't be a perfect measure. There would be those younger than 18 who died because they had graduated, or dropped out, or were absent at the wrong times. There might be a few older than 18 who survived - maybe late graduating, or happened to be doing the health-whatever. They could be few enough to not be influential on your society, or perhaps they were few enough that they did wrestle with the kids for control...and lost, but they would be there. Another option would be to tweak your society slightly, to *make* some event compulsory at or after 18. Maybe a citizen oath or registration or health check or something, that they have one year from their 18th birthday to accomplish - and some exposure or side effect from whatever happens during that is what makes the adults susceptible. You would loose about half of your 18's, since some would have done it and some not (or your could just say 19, I guess). You might also have a few off-the-grid types who resisted, but again the number could be small and for whatever reason not influential. Or maybe have all adults required to be present in their local coming-to-adult citizenship meeting each year (or season, etc) to affect everyone at once. Again, a few adults might be missed, but they don't have to be enough to be influential. Or to go in a completely different direction A lot of illnesses may have different strains or adaptions going on, and we might end up with a population exposure difference. One option might be that, if a variation of the illness (or a related one, or even a different one) was sweeping the schools just before the apocalypse-illness got started, maybe they sent all the kids they could into communal quarantine - especially once they realized kids were surviving where adults died, and maybe they didn't know it was strains rather than age-related protection. A fair chunk of post-pubescent kids might survive just from not being exposed to the adult version, and/or getting protection from catching a lesser strain (like cowpox vs smallpox) - which showed up in schools and spread like mad. Maybe with a plot point that adults didn't catch that lesser strain because of some prior vaccination or medication or something (since phased out), which the apocalypse-virus was just different enough to slip by. Maybe it was a few quarantines of teens for an unrelated illness, with prepubescent kids surviving the apocalypse-illness due to age-related expression, with only whatever teens were in quarantine surviving due to not catching it, but afterwards taking leadership roles (and generally being visible) because the littler kids needed them. [Answer] Vaccination would seem to be your only option. It would not save **all** children or kill **all** adults, but you could get into the very high percentages quite easily. For example, an update to the standard MMR jab that included a polio vaccine could become the new normal. 15 to 20 years after it is introduced a new fatal strain of polio wipes out everyone not vaccinated. The result would be that 90% or more of all children would survive the initial infection, but 99.9% or more of all adults would not. [Answer] Here's a keep-it-simple answer: An alien race decides to do a "reset" of the planet - killing off all the adults for some offense the planet has committed. I don't believe any explanation is necessary how their advanced alien tech is able to know who is an adult and who is not. In fact, no explanation is necessary for even why the aliens decided they needed to do this. Speculation on this question could be an interesting weave in the story. If you must have a scienific explanation for how they know the adults from the children, have a look at <https://www.thenakedscientists.com/forum/index.php?topic=31107.0>. Basically the important part is that we know where we can find cells in the brain that are as old as the individual and we can assign an age to those cells using some variation of carbon-dating. Reminds me of a short horror-story I wrote once where all the meat-eaters get mad-cow disease and the world is taken over by ... (scary music here) ... vegetarians. [Answer] One government developed a super weapon that can kill specific targets based on their DNA (with the intention of being able to poison a water supply and only kill the intended victim). Now combine that idea with a country that logs the DNA of all citizens of voting age (so they can be certain that everyone only voted once, because their vote is tied to their genetic signature) into a central database. Somehow the database gets linked up to the weapon (which is constantly flowing into the water supply) thus killing everyone whose DNA was in the database, i.e. everyone of voting age. Only downside is that it could only really affect one generation unless the future generations continue adding their DNA to the voting system and don't make the connection. [Answer] Herpes. Most people who have it don't even know it so it spreads. People with weaker immunity have cold sores and stuff. This idea would kill off some kids but not the bulk (vaginal births and kissing relatives expose youngin's). There's been research over the last few years that might suggest a possible link between [herpes and Alzheimer's](http://www.telegraph.co.uk/news/science/science-news/12188092/Alzheimers-disease-could-be-caused-by-herpes-virus-warn-experts.html). It could mutate and be fast acting/spreading but essentially Alzheimer's only happens with some age... the early onset could continuously getting earlier but maybe a developing brain wouldn't be effected until early 20's. This would need a generation or two to happen. Shingles is in the same family as herpes. Chickenpox, too, but kids these days get vaccinated. [Answer] Perhaps a natural phenomenon or a world war kind of deal where something is dispersed (chemical, viral, etc.). Or maybe something happens in space like some sort of rays that the earth passes through or a burst of something that envelopes the planet, etc. That way you can account for everyone on the planet and not miss certain populations. Everyone on Earth is affected and is slowly dying. They can still reproduce, etc., but within 18 years everyone that lived on the planet through the event dies, leaving only their offspring. [Answer] ## Think Small Aging (at the cellular level) has been shown to be strongly linked to length of telomerase strands which cap the end of the DNA sequence in living creatures. Interestingly enough, these strands are *species specific*. Should there be a genetic "virus" or similar effect which acts lethally only upon those whose telomerase strands are over a certain length in a given species, you will find that the vast majority of individuals over a given age of said species will succumb to the lethal effects of this most unusual plague. [Answer] Simply have a pandemic infection 18 years ago that made everyone infected (which was almost everyone) susceptible to some new scourge. Among other things, this allows one to explain how a few "oldies" (as many as you want) survive -- they were not infected originally. [Answer] Well, in order for some sort of disease to target only those over a certain age, you would have to examine the physical changes that occur around the age that you're speaking of. The first thing that comes to my mind is the fusion of growth plates (which stops us from growing forever). For males this usually happens somewhere between the age of 16-21, most commonly around 18-19.(Taken from <https://www.zocdoc.com/answers/21489/when-do-most-males-growth-plates-close>) I'm not entirely sure how a disease would trigger based on such a physical change, but its a possible cause. Hope this helps! [Answer] Amy's answer is the simplest. I would prefer to upvote or comment on her answer but in lieu of that... My take is that there is an undetected global pandemic for a period of years that infects everyone on Earth without harming anyone or showing any symptoms. After a few years (once everyone is infected), the virus or whatever goes dormant for 18 years before suddenly killing all those infected. Only those 18 or younger would be left alive. [Answer] Don't target an age. Target a life experience. Let's see... I'm writing this answer in the year 2017. > > In 1985, after Halley's comet flew by, the solar light interacted with the comet in an unexpected way. The reflected light beams had some properties that ionized Earth's atmosphere in a way that caused a chain reaction. The effect took over ten years to develop, but once the catastrophic result occurred, the effect was nearly instantaneous and planet wide. Everyone on the planet breathed in the toxin. > > > However, those who weren't yet born gained an immunity during pregnancy. > > > In 2017, an upgrade to the satellites used by GPS caused a fatal cancer in anyone who wasn't immunized. Unfortunately, the people who caused that problem are now dead, and nobody quite figured out exactly what happened in 2017. > > > You'll probably want to change that significantly. (Blame the Chernobyl explosion, or any other one-time event that hasn't happened in the last 18 years. The beauty of Halley's comet coming by Earth is that you have a need to find a fix to the problem in the next 76-18=58 years, or else the catastrophe might repeat.) The point of the example isn't as much to be your ideal approach, but just to show the general technique: rather than target age, you might want to target specific years. (The precise cause can be different, yet you end up getting the same desired result.) What happened on your planet at a specific year, but then didn't happen again afterwards? Note one downside: It makes your writing timely. That is, if you actually based things on Earth's dates, your writing will seem less applicable 8 years from now, unless you use relative dates (20 years ago) or some other dating system (a non-Earthen calendar). [Answer] **Welcome to the world government elections!** In the year 20nn there will be elections for a world government held over a 24 hour period. (Or maybe a referendum to see whether there will be a world government - it will not matter in the end.) These are compulsory for all adults, defined as being persons 18 years or older, with extreme incentives for participation and penalties for non-participation. In order to avoid election fraud, each voter is required to enter a voting booth, provide a DNA sample and enter their vote. Due to the widely varying definitions of sanity and criminality around the world, no person will be denied the requirement to vote. Oh dear, the antiseptic used on the DNA sampler was contaminated (probably deliberately by terrorists such as apocalyptic religious fanatics) with a fast-acting virus. Or it could be something else - as @Morgen stated, the children won't have the expertise to determine what went wrong or to analyse the impossibly huge failure of risk management. The point is that you have a mandatory, near-simultaneous, activity that all adults will be exposed to and only adults will be exposed to. So long as the onset time is more than 24 hours then no one will be warned in time to avoid exposure. [Answer] 18 years ago, an incredibly hardy and contagious but slow-acting disease spread throughout the world. The germ buries deep in the liver (or maybe brain!), making its eradication pretty much impossible without destroying the liver. Having no immeadiate symptoms, it wasn't detected before pretty much everyone on Earth had caught it. This disease must incubate for about 18 years before it wakes up and kills a person. A vaccine was developed as soon as it was discovered - a cheap and simple vaccine that could be easily distributed to the peoples of the world. The only problem is: The vaccine is only effective on unborn babies still in the womb! [Answer] Well, you won't get *solely* teenagers, there would be some older people in power, but you'd get quite juvenile populace with my method. # An all-outs war As an old grim saying says: "When are 16-year-olds drafted? When there are no 17-year-olds left anymore." So, get all the older people drafted to the army and killed. Let this happen to women too. Let this happen to other side too. The "drawback": Folks in power, elderly, and people required to operate military industry remain. And in an all-out war *all* industry is military industry. So, while the share of women and children increased rapidly, there are still enough adults and older people left. ]

[Question] [ Necromancy is a type of magic that forces a soul back into a body after it has been killed. Through a dark ritual, the soul is forcefully removed from its eternal rest in the afterlife and is anchored back into the mortal world. The soul is under the complete control of the necromancer, and is a form of spiritual enslavement. The bound soul is in agony every moment of its unlife, and expresses its pain by constant moaning that sends shivers through anyone hearing it. These zombies are used for free labor, an undead army, and various other purposes. Necromancy is a vile heresy, and is punished with burning at the stake. People are horrified at the thought of their loved ones being robbed of their well deserved rest, forced back into their dead body, and used as slaves to another's bidding. Necromancers are thankfully rare, and is a difficult kind of magic to learn. However, they have been necromancers in the past who became dangerous threats to civilization, and their names have become infamous. Despite this, society refuses to cremate its dead, as the body retains special significance in this culture. What would be a good reason for people to not cremate their dead when the dangers of this dark magic is well known? What would be an alternative method for protecting the souls of their loved ones? [Answer] # Because there's necromancy and there's holy resurrection. Necromancy is evil, holy resurrection allows the deceased to return to service in the name of god, their cries of joy at being returned to this service sending shivers through anyone hearing them, utterly unlike the cries of torment from the victims of the necromancer. What do you mean you can't tell the difference? You shall be hanged for heresy and then you may begin your eternal service to the great god! --- I didn't think this was necessary, but a surprising number of people have missed out on the fact that the difference between necromancy and holy resurrection is the colour of the robes you wear while doing it. Of course to suggest as much is heresy and we know how that ends. [Answer] If necromancy works the way you describe it, that means there is a link between the *soul* and the *body* of the dead. Indeed, you can force back the soul into its body, but not in another body (unless you told us otherwise). The implication of this, is that if you burn the *body*, what happens to the soul can be more terrible than a mere resurrection. This can be achieved via several ways. ## Eternal burning That one is easy : if being resurrected means temporary agony (temporary being as long as the resurrection takes place), having your *body* burnt could mean eternal agony of the *soul*, like if you were burning for eternity. Basically, Hell. The one problem with this is that there is no proof that the soul goes through this pain (since it can't go back to the livings to tell us so), so it would be only *believed* by the people that burning is, in fact, worse than resurrecting. Or you could have a semi-burnt body brought back to life, but I don't think people will get the difference between constant moaning of resurrecting pain and constant moaning of burning pain. ## Homeless soul If the *body* is burnt, the *soul* can't rest in peace and is forced back to earth, roaming around formless for eternity. This could be coupled with *"Eternal burning"*, so that people could actually feel the pain of this "ghost". ## Ghouls A variation of the *"Homeless soul"* : the soul would seek another vessel, stealing animal corpses (or human corpses, depending on your rules regarding human and animal souls) and attacking/eating the livings. And you can still add the constant burning agony for that matter. With this, clearly, burning bodies would be considered **worse** than necromancy. [Answer] 1. **The risk is low** by some reason: * "Necromancers are thankfully rare, and is a difficult kind of magic to learn." * "Necromancy is a vile heresy, and is punished with burning at the stake."The reward of keep body intact (religion or spiritual value) is outweigh the risk. Thus, people ignore the risk of necromancer and decide not to cremate its dead. Comparing with real life, you know that when you drive a car, you have risk of being killed (accident), but the reward of going fast far outweigh the risk, so you choose to drive a car. Therefore, in this case, dead bodies are protected by statistics. 2. **Countermeasure** - trying to reduce the risk of necromancy: In history, every disease have mortality rate (percent people die to disease). So, doctor invent vaccine and cure to reduce mortality rate. It reduce, but very hard to get 0%. In this case, your citizen can develop some method to reduce necromancy. "Necromancy is a vile heresy, and is punished with burning at the stake." is an example. However, I suggest some more option for you. Like vaccine for the disease, you can "vaccine" the dead body, after or even before their dead. * After dead: holy monk cast some spell to prevent necromancy spell. * Before dead: old people (themselves) go to pagoda, practices light magic, which would protect their soul from dark magic. [Answer] If burning the body destroyed or at least harmed the soul people wouldn't cremate the dead. Instead they might try to hide the bodies of the dead, or use magic to protect them. Would hacking the body to pieces stop a necromancer from using it? Perhaps they'd just reconstitute the body, or raise the pieces into an even more terrifying mangled horror. [Answer] The soul needs time to leave the dead body - it's not something that happens in the moment of death and is done with. Over the lifetime the soul has become attached to the body, and only **the slow decomposition in a hallowed ground will ascertain that the soul rises whole and intact** into the afterlife -- and maybe even beyond to rebirth! Burning the body would also destroy parts of the soul, tearing it apart and not allow it to experience the afterlife at all. A most cruel act, reserved only for the worst of criminals and enemies. Incidentally that very link between soul and body is how necromancy works: It reanimates the body, and the remaining bit of soul will take over the operation of the body. Once the Necromancer's spell is broken, and the artificial conservation of the body, which binds the soul, is no more, the soul will be able to reform in the afterlife, merely suffering a delay, where it is split in two. Although similar to the "ghost" suggestions above, I don't think it's necessary to have and might add unnecessary complexity to a world. After all, a soul's wellbeing should be of paramount importance to the ex-loved ones of the body in question. [Answer] The dearly departed offer aid and blessings to those they feel bonds with. * Perhaps your business continues to thrive because your great-grandfather that started it helps to guide customers your way. * The family sword effortlessly slices the flesh of fell beasts because it carries some small favor from your warrior great uncle. * Your farm has better yield because the family specters of the past all do their part to chase away pests. * You were able to wake up and save your entire (living) family before the fire became too great, because your grandmother's spirit roused you from sleep just in time. These ancestral spirits are only tentatively tied to the physical world, and so, are unable to give constant help. They are often able to act when you need it, though. Unless something has utterly destroyed the body. Once the body is gone, either through action or natural decay, the average spirit can no longer watch over their legacies. Most people would be loathe to destroy the connection to guardian spirits on purpose. However, it may be wise to burn the bodies of particularly awful and hateful people. Necromancy may even have a side effect of twisting the protective instincts into antagonism. An undirected undead may still be drawn to their families, but the pain and torture of the dark magic causes them to attack and destroy what they once cherished. Protecting the soul form such things may bot be possible, different regions may have different approaches with varying degrees of efficacy. Salting the body, or mummification with purifying herbs may go some way to blocking the evil magic. Hiding the bodies, or placing them in durable tombs and mausoleums is likely an obvious choice. Some cultures may remove the skull and keep it safe in the family shrine. It seems that necromancers would most benefit from mass graves post plague or war. They would also likely seek out paupers graves and the bodies of the indigent that have no one to care for their remains properly. [Answer] ## What if cremation didn't actually stop resurrection? In the past, there was such a vile necromancer, and so the people took to burning their dead to stop him from raising a huge zombie army. The only problem was that it turns out his spells still worked on their ashes. They didn't have the amazing strength or the spine-chilling wails of the fully corporeal bodies (it's hard to scream with no vocal chords, of course), but when a black cloud of possessed ashes swept over a city its residents would suffocate in the remains of their own loved ones, and typically provide the necromancer with even more bodies for his undead army. [Answer] I have thought about some reasons, the majority of them can be combined with other reasons. # Expensive Cremate a corpse need much fuel and time, also it's an unhealthy task. Imagine the corpses of an entire army or a deadly plague, it would be impossible to cremate all of them. Also, families of the corpse might not have enough money to pay for a cremation. # Statistic (Low chance) * Each time you drive a car there is a chance to die in an accident. * Each time you fly in a plane there is a chance to crash the plane. * Each time a soldier goes to a battlefield there is a chance of been reached by a bullet. But... Why do people drive cars, fly in planes and are volunteers in the army? They could die... this is because, statistically speaking, there is a really low chance (at least in the two first) to die, people accept the risk in order to: travel faster, feel the speed of a car, fight from the country or even get high doses of adrenaline. Your citizens don't think that they will be victims of a necromancer like you said: > > Necromancers are thankfully rare and it's a difficult kind of magic to learn. > > > So they don't think that they'll be the next victims, there is a **really low chance**. # Religious You said: > > Through a dark ritual, the soul is forcefully removed from its eternal rest in the afterlife and is anchored back into the mortal world. > > > This means that there is some kind of connection, link or tie to your body. Using that I get a lot of conclusions. ## Prison in the heaven This link is our only *backdoor* from the **heaven to the live realm** (Earth). The heaven can be a very beautiful place (or maybe not but see below) but it's isolated from the real world. Some persons (people with have alive relatives) want to see them (the relatives) even if they (the relatives) can't see them (the deaths). If their bodies are cremated, they would lose they door to our world and they won't be able to see their relatives again. ## Burning souls If you burn the corpse, his soul would feel the pain of the cremation. You don't want that your relatives get so much pain in their well deserved eternal rest, no? ## Cremating souls Even more than the last, if you destroy their physical body, their soul will also be destroyed. Here you are literally killing them again, destroying their eternal rest and even "disintegrating" their souls (his conscience, memories will be lost). ## Prison in the real world (ghost) Think about a tree (the link), it has roots (earth), trunk (tunnel) and leaves (heaven). Your physical body is the root, which holds the tree. When you die your corpse hold this tree (or ladder if you want) and you climb to the heaven. Then his leaves let you be there, if you set on fire the roots they will destroy it, the trunk and even the leaves, you would lose the "pillar" who let you be in the heaven and you will fall to our world. You will be here for all the eternity, suffering always cold, heat, thirst, hunger (humans needs) to the eternity and you won't be able to stop them (a ghost can't drink, eat, etc) but also you won't die (ghost are immortals). Again, do you want to make all your deaths relatives suffer this? ## Hell Souls are tied to the bodies by this "magical link" that I am always talking. This lets the souls not enter into the hell. If you break the link (burn the corpse) his soul will be free... free in the bad concept, they will be "free" of the tieds that "protect" him, What? Protection? Yes, the link is like a rope, the hell can't pull off the souls because the link is holding them, but if you break the link the hell would be able to capture them in the endless flames of the hell, an eternal and painful torture... and when the demon god bored with you, he will eat your soul. ## Gods There are legends that the gods will come someday to our world and will revive all our dead relatives and all of us will live happily. If you burn them, gods won't be able to resurrect them and they won't enjoy the eternal paradise in our world when gods come. ## Spectres When you destroy the soul link (body-soul) the soul get "wandering" in earth (similar to the ghost concept). The difference is that this spectre will try to get a new body (of an alive person, of course) and this effect is called "possession". Obviously, you don't want to be possessed by your mother-in-law. ## Spirit's guardians Well, this isn't my idea, I only want to show my agree with [Neocognitron](https://worldbuilding.stackexchange.com/a/84653/35041)'s answer. Sincerely I wouldn't choose his answer but it's very original. ## Soul resurrection Basically, your people believe in the flesh resurrection (after death they will reborn in another animal). Here I have some ideas: * But if you burn his flesh he won't be able to perform the incarnation (he won't have anything to offer in order to complete the resurrection). * The resurrection takes some time (years to complete): + While the soul is in this process it's linked to his corpse, if you hurt the corpse, the soul will be hurt (and his haven't cure, also this can explain why some people born with diseases), if you burn it, you will destroy the soul. + The process is very slow and need the corpse to accomplish, you have to produce a slow but constant transference of the soul from the corpse to his new body (this take 9 month), in order to transfer the soul to his new body the last has to be destroyed **in a slow process** (exactly the same time needed to make the new body). Putrefaction destroys the body with a perfect rate, it's too fast (like fire) nor too slow (life mummification). # Alternative My ideas about how to protect the souls very simple, and are almost compatible with all my ideas. * **Enchanting/Blessing:** With a magic charm or the blessing of a cure you can protect the soul from necromancers or be able to burn his body without hurting him. (Ask help for god to protect the soul / Make immune the soul to the hell / Break bad connection of resurrection, etc). * **Making a new link:** Almost all the problems involved with burning are that they broke his link/bond/chain/tied to the real world and them they are wandering forever, been tortured, possessing bodies, insulated in the heaven, etc. You could build a (or some) magic/s monolith/s in where you enchant the soul linking it to the monolith instead of the corpse, solution! Also, with this method maybe you could think about what would happen if the monolith...is...broken... [Answer] > > People are horrified at the thought of their loved ones being robbed of their well deserved rest > > > Not necessarily. **Love makes you do crazy things; grief makes you do doubly-crazy things.** Have you ever watched *FullMetal Alchemist*? The central premise is that the two main characters, grieving the premature death of their mother, resort to the ultimate taboo: transmuting her back to life using alchemy. (Spoiler alert: it doesn't end well.) A similar scenario might occur in your world as well. A mother loses her young son in a tragic accident. She's consumed by grief; she refuses to accept his loss. She knows the dangers of necromancy, and the punishment if you're caught, but she doesn't care any more: she just wants her son back. The funeral director asks if she wants him to be buried or cremated. She chooses buried. The next day, she visits the shady part of town and buys a book on necromancy from the black market. The seller asks if she's aware of the consequences of necromancy. She is, but she doesn't care: she just wants her son back. The burial takes place, and the mother seems strangely calm throughout the ceremony. That night, she returns to the grave in secret, the book of necromancy clutched in her hand. It's not going to end well; not for her, not for her son, not for anyone involved. If she stopped to think for a moment, this might occur to her. But she hasn't been thinking straight ever since her son died. *She just wants him back.* [Answer] # 1) Weaponization The bodies of the buried ones form strategic defenses, to be activated by a three letter government agency if the country is faced with an immediate existential threat (i.e. an invasion). The undead are in agony, but hey, it's just temporary (unless the enemy wins and binds them to serve him - this gives the undead extra incentive to fight) and not much worse than conscription (and those serving in the army during their life might even be exempt from the afterlife service). As the part of the defense program, the government might even subsidize cemeteries at strategic places. # 2) Life preservation (Almost) nobody wants to die. Given the evidence of a possible resurrection, this is the equivalent of our cryopreservation. A hope that sometime in the future, science will solve the "agony problem" and resurrect you, hopefully while giving you enough personal autonomy. If the agony is physical, throwing enough painkillers in might help. If emotional, research the cause - eventually, the holy grail of the necroresearch is to find the soul anchor and the way to transfer it to a fresh young (vat grown, unless you are an evil bastard) body, letting your previous body do the incantation, so that you are kind of enslaved only to yourself. # 3) Escaping the worst If the christianoislamic concept of Hell turns out to be correct, then letting yourself be resurrected in agony and enslaved might still be preferable to the torture you'd suffer otherwise. First, resurrect the person, ask them if they are in hell or the other place, and if hell, keep them resurrected. Rich people might set up trusts and committees, poor one have to rely on their grandchildren. This is all rather bleak, but you might still hope to solve the "agony problem" (see **2)**) [Answer] 1. Possibly religious reasons, that could work up to some seriously conflicting worldviews. For example, taking convention in your world that necromancy is bad. But as you noted, necromancers are burnt at the stake. So, logically implying that burning bodies (live or dead) is an impure/tainted death with probable repercussions in the afterlife. Thus, people don't want to cremate their dead. 2. The number of necromancers that come up from time to time is a very important factor to count in here. Rarely in the real world do you see a certain population adapt itself by changing customs to accommodate a minority. Suppose the necromancer infestation is a recent problem, and the concept of fire deaths being bad/evil exists for centuries. Or maybe they did coexist, but the necromancers are significantly smaller in number than majority population, so people's fears increase. 3. The price of cremation. Imagine, that a cremation was not as simple as lighting a body with wood. If it had complicated rituals involved in the customs of the people, then the poorer sections of society would not be able to do anything except for mass burial, necromancer or no necromancer. Or think up some sort of class divide, i.e. only the lords and officials above a certain rank can be cremated, leaving the other people with no other choice. This of course assumes the absence of coffins, as poor people simply dump their bodies in holes in the ground, as traditionally, coffins are more expensive than simply lighting a body. 4. Epidemics or other reasons for massive deaths. Imagine a specific incident had taken place in the past, i.e. some battle/extermination/flood/epidemic. Cremations are costly, fuel is precious, so basically, a huge pit was dug, and bodies dumped in a mass grave. This works for especially poorer people who might have suffered in such a manner. A necromancer learns the location of one such mass grave, hey presto, you have an undead army. Now imagine something of the size of the Bubonic Plague. There is no single huge pit, instead, every town has had such pits, although their locations have been lost centuries ago. So, necromancers can simply research the graveyards well, and they can form a practically unbeatable army by adding to their "collection" as they pass through each town. [Answer] Easiest is just "flesh resurrection": in many cultures (including Christianism, up till recently) people believes after the end of the world there will be a Trial for everybody and the flesh will resurrect. If You burn the body You condemn the defunct to remain forever a ghost. This is also reason behind burial rituals and some embalming (e.g.: in ancient Egypt). [Answer] Because if you have bad, bad necromancy you also have nice necromancy. Because you see, people like to change their minds. For example typical necromancer in dark robes, skulls and with a name like Obyntrontinx is vile and heretic. On the other hand you have a necromancer wearing white robes, smiling and calling people by name. And he's a nice fellow, almost everyone like him. Let's call him Jesus. Of course in both cases there will be people who will say "well, it's bad in both cases. We gave dead people tax reliefs." But you can convince them it's ok because it's "our" necromancer. OR kill them if they are stubborn. Soto summarize - the people don't burn corpses because when they are alive and not dead yet they say "hey, don't burn me. I'm waiting on the good necromancer". [Answer] Religion is the most obvious answer. If cremation wasn't acceptable in the religion, it would be rare. Religion would also be the method of protecting the dead. A good [insert religion here] burial involves blessing the corpse and burial in consecrated ground which prevents necromancy. Necromancers would try to get their bodies from corrupt undertakers before the funeral or just make their own. Once the funeral was over, the body would be no good to use so no point robbing graves. [Answer] 1. Create a time limit during which you can resurrect a body. If necromancy works by summoning the soul back to the body, there must be a connection between the two even after death. Presumably, this is due to the fact that we are all somewhat *attached* to our bodies (pun intended). Logically after some period of time after death, one would start caring about his/her former body less, weakening the connection and making the summon harder to perform. 2. *People are horrified at the thought of their loved ones being robbed of their well deserved rest, forced back into their dead body, and used as slaves to another's bidding.* Necromancy *requires* access to the corpse. If the risk of resurrection is so high as to be worrying then all you have to do is *protect the body.* Cremation is an unnecessary extreme. (Albeit an effective one.) [Answer] Perhaps the society believes in *reincarnation* - in which case the soul may be connected, resting peacefully, to the body until its new life can begin. Necromancy would then be easy to describe as it's a reawakening of the attached soul, whereas burning or destroying the body would consign the soul to eternal oblivion; doomed to never return. They may see this as a fate worse than undeath. This also gives rise to the idea that you can only reanimate the recently dead, as the reincarnated soul will have moved on and there will be nothing to animate. [Answer] **Because cremation makes monsters that are even worse.** You think what necromancers do to *corpses* is bad? You ain't seen *nothin'*, friend. Wait until you see the most terrifying monsters in the necromancer's arsenal, the Infernal Wights. Once thought to be the departed souls of those unfortunate enough to suffer death by fire, no, it turns out that the mere act of desecrating a human's body in fire, even *after* death, has horrifying, infernal consequences should the soul ever be forced to re-inhabit their ashen remains. They become a flying, perpetually-shrieking specter of white-hot fire, knowing nothing but the perpetual searing agony once thought to be the domain of hell, and hell alone, and unable to think of anything but how to inflict it upon as many others as humanly possible. Yeah. Sure. Cremate the dead. Have fun with that. Society outgrew that little fad a while ago. ...This isn't to say that they don't have to deal with the things. After all... some especially vile necromancers may burn corpses on *purpose*... [Answer] Desecrating the bodies of the dead to stop their being desecrated? Kinda defeats the purpose. One dissuades necromancy by inculcating in the young the duty of respecting the dead, not by treating corpses as things you dispose of like trash. [Answer] ## Religion As many people have suggested, religion would play a major part in this. The religion could say the body *has* to be buried (maybe you have a god who is a god of the earth, and the soul needs to be buried in order to reunite with the earth), or that bodies must remain intact so as not to destroy the soul. Maybe people also believe that practicing necromancy kills or otherwise tampers with your soul, so why would anybody do it in the first place? ## Decomposition Alternatively, you could say that the body can only be effectively reanimated when all the flesh is there (like the muscles, which would allow it to move). The flesh begins to... *liquify* after a month or so, which might result in bodies being kept in secure places until the flesh is gone, where they are then laid in the ground. Maybe something is done to speed up the decomposition. ## The Corpse Guard Graveyards could be well protected. You could have a special "Corpse Guard" in your world, and it's considered an almost holy duty to protect the bodies from necromancers. [Answer] When a Human's body is incinerated, living or dead, their soul is condemned to Hell. That is why they burn Necromancers at the stake. But no-one would willingly condemn their friends and family to that. A few years of pain as a necromantic thrall are nothing compared to an eternity of anguish and torment. And this only applies when one or more Humans deliberately burn another. Natural and accidental fires do not result in this. As a side result, arson would be considered one of the worst crimes, because if the fire kills someone, you are sending them to Hell. So it is worse than ordinary murder. [Answer] Because it makes for a better story. On a side note, anyone remember how the dead were big business in the 1999 game Planescape Torment? Cool game by the way, and a great explanation as to why they didn't cremate their dead: the de facto Necromancer's guild paid them good money not to and the undead were the city's chief source of cheap labor. [Answer] I really like the approaches of Radovan Garabík. Then of course there is the ace in your sleeve, inofficially of course, as necromancy is illegal... If you are an important dynasty you might want to entomb your most important generals and war heroes and counselors and predecessors in pompous metal sarcophagi in the ***temple of eternal sleep***, which is one of the highest honors in the realm. Inside the palace walls and heavily guarded all the time this mausoleum is said to be the safest final resting place. However, in case the palace is under attack or the realm faces a threat, one of the deceased has successfully fought back in his life... there are old, crooked ways underground, once part of the old palace... no one would notice the high priest and the archon on their way to the *council of dust*... necromancy might be heresy... but not forgotten... (cf. Herbie Brennan's *The Purple Emperor*) And then again, what if the evil necromancer is able to sneak into *that* temple... Don't forget - being illegal and/or dangerous doesn't mean that it doesn't happen in secret. You could compare the use of necromancy to the use of hard drugs or murder that occur throughout all social classes. ## The more important question is: Which story aspects force you to prevent your society from burning their dead? If I learned one thing from [Burke and Hare](https://en.wikipedia.org/wiki/Burke_and_Hare_murders) it's **how easy corpses are to produce**... As necromancy is prohibited, why should anyone revive corpses that are officially known to be dead? A freshly reaped lazar can be useful for several days in winter without attracting any attention, before the smell gets too strong, making a tragic accident neccessary - those robbers in the slums, what a shame... And you really thought it was the kind-heartedness of the highborn widow to open a shelter for the homeless in the slums... As for the moaning - I'm not a healer but I am sure there are parts of the human body that, if cut out, will prevent any form of moaning... Maybe burning the corpses is even mandatory for safety reasons in the city. Until then the undertaker has to store them securely. So if one of them might be stolen, why should the undertaker endanger his own life by mentioning that... and if he gets a better offer... ashes are ashes... only the rich can afford a glorious pyre, the poor will never know what they took home in that urn... And then of course there are the **ancient battlefields**... Maybe the soldiers burned their comrades to prevent them from suffering... but their foes? How long has it been since a necromancer was seen anywhere? So why bother for these corpses, somewhere at the fringes of the realm... thrown into the lightless depths of the nearby marshes or hastily buried in mass graves... a whole army, at your command, Sir... [Answer] Ghosts are considered important sources of information and usually desired, but their availability is partly dependent on the state of the body. Until the body decays enough, it provides a beacon to the soul in the afterlife, allowing it to return as a ghost should it be willing to put in the effort to make the trip. As the body decays, the beacon fades, making return visits harder and harder until, once the body is reduced to just a skeleton, the beacon goes out and it's no longer possible for the deceased to find their way to the land of the living to appear as a ghost any more. Cremating someone greatly accelerates the process, which is exactly why necromancers are burned at the stake, rather than given a cheaper death like a hanging. Nobody wants them coming back as a ghost and finding an apprentice to teach, so onto the pyre with them! [Answer] Because necromancy - all mambo jumbo aside, is just fantasy automation, and if people want to have a job and purpose in life, the dead have to go. Also the dead work 24/7 so, how is a living person to compete with that? [Answer] **They believe cremation destroys the soul. A resurrectable body proves that the soul still exists** In the real world, a lot of Medieval and Renaissance theology was concerned with the nature of the human soul: is it eternal? which souls go to which place after death? Churches sold 'indulgences' to people which claimed to reduce their dead loved ones' time in purgatory. People were (and are) very concerned about death and what comes after. And a resurrected corpse proves that the soul is eternal. It moans to show the agony of the soul within! It's demonstrable and repeatable. But if you cremate the body, does the soul live on? How do you know? You can no longer "test" for it's presence with necromancy. What if burning destroys the soul? Would you risk doing that to your loved one, to avoid the remote risk of necromancy? There's more chance of being struck by lightning! Once the idea that cremation destroys the soul exists, there will always be people too fearful to cremate their dead. What's worse? The *risk* that they'll spend a few years in pain serving a necromancer, or an eternity of nothingness, denied their final rest in a paradise beyond the world? [Answer] # Ecosystem services The power of hallowed ground leads the departed ones to their rest. But it also leads *other* miscellaneous spiritual toxic waste to its rest. Any manner of failed astral tomfoolery, simulacrum-building gone wrong, or misguided attempts at cremation can leave you with a wandering spirit problem ... and your townspeople don't know how to build a particle accelerator, not even an unlicensed one. But spirits have an urge to get into *bodies*, and since most of them lack the mojo or training for a proper possession, that means clinging to bones in some forlorn instinctive attempt to will them back to life. Maybe it would *work*, eventually, in a some dark corner of your world. But in a hallowed cemetary, they are led *somewhere else* by some mysterious power, leaving normal folks at peace again. Although the buried dead are a risk in the case of abuse, they are ordinarily seen as a defense mechanism. ]

[Question] [ **Closed.** This question is [off-topic](/help/closed-questions). It is not currently accepting answers. --- You are asking questions about a story set in a world instead of about building a world. For more information, see [Why is my question "Too Story Based" and how do I get it opened?](https://worldbuilding.meta.stackexchange.com/q/3300/49). Closed 4 years ago. [Improve this question](/posts/158380/edit) I time traveled to the date of April 14th, 1912 with my time machine. It’s evening, 6:00 PM to be exact and my location is the deck of the ship Titanic. We all know what is going to happen not too long from now. I need to survive. So my question is: what can I do to survive the midnight sinking? One important thing I need to say is that I *cannot* under any circumstances stop the Titanic from hitting the iceberg. The Titanic must hit the iceberg tonight. And in order to change the timeline as little as possible, I want to stay under the radar as much as possible. Important thing to say, I’m already wearing a Radiation Suit [Answer] Befriend and hang out with fellow passenger, [Margaret (Molly/Maggie) Brown](https://en.wikipedia.org/wiki/Margaret_Brown) then follow her to lifeboat #6 which historically will have available seats. [Answer] *As soon as a lifeboat launches, volunteer to be in it.* At first there were quite a lot of people who hesitated to go into a little wooden boat in the middle of the Atlantic, when the big reassuring liner still had power and light and was merely stopped. --- Here is the [wikipedia link](https://en.wikipedia.org/wiki/Lifeboats_of_the_RMS_Titanic#Launch_of_the_lifeboats) looked up by DevSolar. Pryftan is right, a source never hurts. [Answer] **Buy a first class ticket** [](https://i.stack.imgur.com/YV8Va.png) If you had a child with you would increase it more. You could also have your life jacket with you and wait near the lifeboats. Being a woman would also increase the odds. > > Even if you were a first-class passenger with a higher likelihood of > getting a seat in a lifeboat, your chances of getting that seat > increased if you were a woman or child. The “women and children first” > rule applied when loading the lifeboats, although the rule wasn’t > strictly or equally enforced. If a lifeboat was about to be launched > on the starboard side and empty seats were available, men could take > the seats if no women or children were at hand to take them. On the > port side, however, it was more apt to be “women and children only” — > very few men escaped the ship from this side. So if you were a man, > your chances of survival were greatly increased by going starboard, as > opposed to going port. > > > [Titanic passenger survival rates](https://www.dummies.com/education/history/titanic-passenger-survival-rates/) [Answer] You're on deck, which is the most important thing. Your survival odds are already waaay up. It'll be cold on deck. Wear a big coat. Underneath your coat, wear a good [dry suit](https://en.wikipedia.org/wiki/Dry_suit) with some high-quality thermals underneath (possibly battery heated ones). The photos on the Wikipedia page notwithstanding, a drysuit needn't make you look like an astronaut, especially a suit that's intended for short term use whilst swimming, not diving. Even if you don't get into a boat (and as the other answers have said, you should be able to do this) you'll be *vastly* better off than anyone else in the water. The lifeboats didn't move far away from site of the sinking, but they did not dare to return to collect swimmers for fear of being swamped and overturned. As a result, most of the swimmers died of hypothermia, but *you* don't need to let that happen to you. Swim out to the boats... one of them will eventually let you on board, or haul yourself up onto one of the bigger bits of debris and await rescue. [Answer] The simplest way to ensure that you yourself - and as many others as possible- survive the Titanic disaster is to distract the forward lookout at the critical moment so that he does *not* give warning of the iceberg ahead until it is too late to turn the ship... if at all. If the means by which you distract the lookout is to offer him the use of your period-appropriate 10×50 binoculars - there were no binoculars on board, as they had been forgotten - with a comment that you had seen that no-one was using them, and the ship's speed in these conditions was making you nervous, no-one could reproach you: you saw a matter that compromised safety, and you acted as expeditiously as possible to correct matters. You didn't approach the other crew in fear it would take them too long to pass the binoculars on to where they were needed, a fear that proved to be well founded, as the ship struck an iceberg right afterwards. What will this do? Instead of the Titanic grazing along the side of the iceberg, it will most likely impact head on, crumpling and breaching the bow compartment, and possibly the next compartment back, and transmitted shock may cause other leaks. However, the ship could remain afloat with the first several compartments completely flooded, and the ship's pumps could likely keep ahead of the minor leakage caused by shock. It may be a close call, and the Titanic may settle quite deeply by the bow before it reaches equilibrium, so it is not impossible that the passengers may be put onto the lifeboats, especially as a direct impact will cause a lot of otherwise insignificant damage and minor injuries. In the following investigation, it could be pointed out that the captain was driving the ship at a reckless speed given the conditions, and had the lookout done his job just moments earlier, the ship might have sunk as a result of a glancing impact rupturing many more compartments, plus the triple-screw design meaning that the ship could not turn as rapidly as an even-screw design. So... the disaster happens... but most will survive, even if it is discovered that there were not enough lifeboats. Failing that... bring and wear beneath your clothing a drysuit made for diving in Arctic conditions, and be sure to remain on-deck. [Answer] Locate crew member [Jack Phillips](https://en.wikipedia.org/wiki/Jack_Phillips_(wireless_officer)), the ship's "senior wireless operator". Making a few changes to his timeline this evening will increase your chances of survival immensely. The general idea is that the *SS Californian* was in the vicinity and had the capacity to save essentially everyone on board the *Titanic*, if only they were aware of the disaster. On that fateful evening, Phillips had a massive backlog of work. The ship's wireless operator was responsible both for sending and receiving "official" communication as well as personal messages sent by passengers; he was employed by the Marconi radio company (not a ship crewman) who charged a fee for these personal messages, so they were viewed as equal importance as ship-to-ship messages. Phillips spent many hours that evening transmitting overdue personal messages. The transmitter had broken the day before and he was a full day behind on sending these messages. The radio operator on board the *Californian* transmitted an ice warning at 10:55 PM. Since the *Californian* was relatively close and the relay station used for personal messages was far away (Newfoundland), the message from the *Californian* was significantly louder and was drowning out the signals coming in from the Newfoundland relay station. Phillips responded to the *Californian*'s message with a snippy, aggravated "shut up!". The radio operator for the *Californian* responded to this rude response by shutting off his radio and going to bed for the night. He missed the *Titanic*'s distress calls, and the next closest ship was too far away to respond in time. You have several options here: * Eliminate Phillips' backlog so that he's less stressed and (ideally) can finish the personal messages well before 10PM. Break into his cabin and steal/destroy most of the messages in the outbox. For a less destructive option, explain to him that you just discovered that your three mischievous children have been writing numerous fake telegrams and dropping them into the messages box over the last several days. Apologize for their behavior and ask if you can skim through his outbox and pull out those that look like they were written by your children. Once he's given you access, remove and discard at least half the pile. He should now finish early and be alert and ready at the fateful hour, preventing the rude reply that sent the *Californian*'s operator offline. Keeping them online for a mere half hour would enable them to pick up the initial distress call and respond immediately. * Disable the wireless transmitter in a way that you can reverse. The transmitter broke down the previous day, so it wouldn't be too surprising to Phillips if it broke down again. Do this as soon as possible. After Phillips gives up, reports the radio as broken, and goes to bed for the night, you'll sneak into the radio compartment and take his place. The *Californian*'s ice warning comes in at 10:55 PM, so we know their radio operator was working until at least that point. Send a pre-emptive distress message around 10:30 PM. Use both the traditional "[CQD](https://en.wikipedia.org/wiki/CQD)" distress code as well as the new "[SOS](https://en.wikipedia.org/wiki/SOS)" distress code. By the time the ship hits the iceberg, the *Californian* should be close enough to shuttle you (and most everybody else) off of the *Titanic* via lifeboat. * Tamper with the radio in a way that leaves it operational, but either reduces the antenna's signal gain considerably or introduces low-level background noise. The goal is to reduce the ship's effective communication range. The Newfoundland relay station was roughly 375 miles away, which is close to the max range for the ship's radio. Cutting the radio's effective range down to ~275 miles means Phillips can't get bogged down with passenger messages, but still has plenty of range to communicate with other ships and send distress signals. * Chat up Phillips and talk about how you were in the Army signal corps until a few years ago. Ask whether the ship still has [signal lanterns](https://en.wikipedia.org/wiki/Signal_lamp) (it does), or if it's all been replaced by that newfangled wireless stuff. Remember where he says the signal lanterns are located. Around 11:10 PM, an officer aboard the *Californian* attempts to contact an unidentified ship in the distance (the *Titanic*) via signal lantern, but receives no reply. Man the signal lantern at that time and when you see the *Californian*'s signal, reply. Identify your ship, request emergency assistance, and report your radio is down so they don't try to contact Phillips and get a different story (you haven't actually hit the iceberg yet). With any of these options, you run the risk of not being able to access the ship's radio room. Fortunately, the radios of the time used relatively primitive "spark-gap" transmitters. It's not that difficult to [build one yourself](https://steemit.com/steemstem/@proteus-h/diy-spark-gap-radio-transmitter-and-explanation), especially if you have access to modern components (I assume you do since you have a time machine). The antenna for the radio system was a massive wire running between poles mounted at either end of the ship, with a wire running between the middle of the overhead wire and the radio room. If you disconnect that wire and attach it to your radio, you've essentially replaced the ship's onboard radio with your own and you're now the signal officer. Here's hoping you remember Morse code. [Answer] 1. Get in your time machine and leave. 2. Bring your own dry suit and Arctic survival gear so you can go in the water without risking your life 3. Bring your own inflatable life raft 4. Lock the proper doors so the **hoi poloi** in steerage can’t get to the life boats, ensuring there is adequate room for you and no pushing and shoving 5. Use the pistol you brought back with you to force crew members to launch a life boat or the captain’s gig early, before the impact so you are away and clear. Make sure to murder them before you leave so they can’t go whine to the Captain and change events [Answer] # Get first class and dress as a rich woman of that time First class women had the best chances of survival. Get hold of a first class location and/or ticket. Even if you are female, you need to get conforming clothes, your 21st century wear needs to be recognized as 100% female in an emergency, you cannot risk it. If you are male, you also need to shave and you need to do it as soon as possible. Your best chance for obtaining the needed clothes is kidnapping or seducing a drunk passenger from first class. In case you go for kidnapping, you can try going for a seasick first class female passenger. If you get the chance to prepare for the journey, you go for [Miss Edith Corse](https://titanicfacts.net/titanic-passenger-list/#1stclass) as to not interfere with the survivor list. [Source for chart.](https://rstudio-pubs-static.s3.amazonaws.com/185508_5c6b7ef40dd9438b82239c4b57ec9ab4.html) [](https://i.stack.imgur.com/ScI57.png) [Answer] Well, from it sounds like, the lower decks for the poor folks were locked off which made it impossible to get outside. So, don't go there. From what I've seen, the boat rose up and then cracked in half. The middle would be bad because you're going to end up plummeting into the water along with a whole mess of wood, metal, and screaming bodies. I don't recommend that either. The prow rose the highest and that is probably not a roller coaster ride you would enjoy. If you don't have a way of bracing yourself, that is probably not a good place either. The furthest part in the back is also probably bad because the impact with the iceberg is going to cause everything to shake violently and anyone on the rear decks are probably going swimming. Likewise, large rooms filled with glass windows are going to be deadly as everything shatters. Not to mention you're going to have to walk through that. Crowds in general are going to do what crowds do which means you get a fluid-like dynamics in the panic. This means that your danger is less being crushed by people. The biggest danger is when the "ripples" of people push back, you are most likely to be knocked off your feet. So, having some sort of wall to brace against will help with this too. So, I'd say near the back and near the lifeboats. Somewhere relatively small and able to handle jostling, such as a linen closet or somewhere you can bounce off the walls, recover, and head to the boats right away. If you are one of the first on the boat to help others, that would be best for getting on and out of there. I'd also make sure there were better supplies under the seats if you could. Now, if you happen to fall in the water, I highly recommend you avoid massive wooden doors with just one person on them. They don't share and you are going to dramatically drown. [Answer] **You must demand entry aboard the SS Californian.** The Californian was roughly 5 miles away from the Titanic after it struck ice. Because it was so close, the idea of rescue was not out of the question. Therefore, you should volunteer to enter a life boat headed towards the Californian when they are first launched. It is, however, well-known that the Californian ignored emergency rockets and the Marconi wireless operator was not at his station during the crisis. However you choose to convince Captain Stanley Lord is up to you. [Answer] # Find "Rose's door" I mean this seriously, but figuratively. In the movie, the floating door was how Rose survived. It was a literary device to allow a believable, yet unexpected way for her to live to tell her story. Create "Rose's door" for your story. It could be a paddle, maybe some kind of semi-waterproof wrapping, a makeshift wetsuit, or even a buoyant bathtub. You might even survive by floating in your time machine itself. That would be the "least likely to contaminate the timeline" while allowing you to be witness to more. Think "fly on the wall", or "Rose on the door". Be creative and inventive. --- **Note on comedy:** If you are going for some comedy, you could make it an actual door, perhaps even drop a line, "I remember someone survived by floating on a door." Especially in time travel, some tongue-in-cheek humor makes the medicine go down. Comedy often plays a role in time travel, consider *Back to the Future* or *Avengers: End Game* where Captain America fights himself. [Answer] 1. Travel first-class (or if you're transporting directly onto the ship without a ticket, make every effort to *look* like a first-class passenger). This gives you [a 62% chance of survival](https://www.anesi.com/titanic.htm), compared to an overall 32%. Since you're a time traveler, I assume that you've already gotten rich from bringing back winning lottery numbers and stock quotes from the future, so this will be easy. 2. If you're a woman, you've got it made, as long as you're on the boat deck while there are still lifeboats left to launch. If you're a man, then make sure to be on the **starboard** side of the ship, where Officer Murdoch was [more willing to let men into boats](http://www.premierexhibitions.com/exhibitions/3/3/titanic-artifact-exhibition/blog/truth-behind-women-and-children-first) than his counterpart Lightoller on the port side. 3. If it's getting late in the sinking **do not** follow the crowd towards the stern, as they'll mostly be doomed. Instead, head **forward** towards the officer's quarters, where the four collapsible lifeboats are kept. These will be the last boats to leave the ship. Volunteer to help launch these boats, as the crew will be struggling with them. [Answer] I think the most reliable way to survive would be to get the radiation suit off (they're very good at helping people sink) and get back to the time-machine. You're wearing a radiation suit meaning at best you'll get funny looks from everyone - which while it might seem it won't matter (since most of them will die anyway) could seriously impact the timeline. In addition, you don't actually need to jump too far. A jump of 30 minutes after the sinking will have you in the water just as the Caroathia is arriving. The joy of this, is that it was pure luck that they were able to locate the survivors at all, since they had drifted and only a flare alerted the rescue teams to the new location. By making that jump just a little further; you can be the one that happened to look the right way at the right time to see the flare. (if one was ever launched!) [Answer] I would attempt to steal a lifeboat and depart from the ship prior to the accident. [Answer] Are you planning on coming back to your own time? If your time machine is on the Titanic then obviously it's going down with it. Unless you joined in port and the machine is there, in which case you're obviously having an extended visit during which you'll already have had to blend in during the journey, and will have to continue to do so until you can get back to Southampton/Cherbourg/Cobh to collect the machine. In either case, the simplest answer would seem to be to research somebody who is known to have survived, including which lifeboat they were in (or how else they survived). Kill them before the journey (if on board since port) or at least before the ship sinks (otherwise). Although the latter may not be necessary - perhaps the always drowned and you're the one recorded as having survived. Take their lifeboat seat, and you're safe. If you're not planning on returning to your own time, you'll need to keep up the pretence of being this person, so best to choose someone you bear a physical resemblance to, without close family (maybe the whole family die on board?). If possible, make some previous reconnaissance trips to learn more about the individual, or even introduce yourself to some people as them in order to help maintain the fiction. If you are planning to return, pick someone who was died shortly afterwards. This actually works out simpler if you've been on board since port, since you just kill them before the trip and stash the body, take the trip as them, then when you return to collect your time machine you leave there body to be discovered as it always was. Finally, killing them before the trip rather than on board (or just letting them die in the sinking) is probably preferable since at least you know before you board that it's *you* that survives. Otherwise maybe something goes wrong and it is actually them, and you're lost with the ship. ]

[Question] [ Let's say that an ancient race of beings locked away some sort of evil that could destroy the world if unleashed. Let's also say that unleashing it would be relatively easy to do if not warned of danger. Using only Aztec or Ancient Egyptian level technology, how could the race warn the future not to mess with the evil being's prison in a way that would last an absurdly long time (let's say for simplicity it needs to survive 100,000 years) that can be easily comprehended by anything and anyone, considering how much language changes in only a few thousand years. Note: The ancient race can work together on an Ancient Egyptian scale, but has no access to magic or modern technology. Edit: Pardon the weird and contradictory circumstances in which they need to warn others, but the question is how to do so, not why they need to. Also, it's reasonable to say that people are curious and will eventually do what they're not supposed to, but that's irrelevant to what my problem is here. [Answer] This problem has actually been considered very seriously by very serious people, in the context of warning future generations of the [dangers associated with long-term repositories of nuclear waste](https://en.wikipedia.org/wiki/Long-time_nuclear_waste_warning_messages). * The [Human Interference Task Force](https://en.wikipedia.org/wiki/Human_Interference_Task_Force) was *"a team of engineers, anthropologists, nuclear physicists, behavioral scientists and others [...] convened on behalf of the U.S. Department of Energy and Bechtel Corp [with] [t]he goal [...] to find a way to reduce the likelihood of future humans unintentionally intruding on radioactive waste isolation systems"*. * One of the best documents in the "[Expert Judgment on Markers to Deter Inadvertent Human Intrusion into the Waste Isolation Pilot Plant](http://prod.sandia.gov/techlib/access-control.cgi/1992/921382.pdf)", Sandia Report SAND92-1382 (1993), Kathleen M. Trauth, Stephen C. Hera, Robert V. Guzowsti, eds. > > *Expert elicitation was used to determine the potential for markers to deter inadvertent human intrusion by future generations into the [Waste Isolation Pilot Plant](https://en.wikipedia.org/wiki/Waste_Isolation_Pilot_Plant) (WIPP). Specific goals were to obtain information about marker designs and message formats that will remain in existence and interpretable for the required time period of regulatory concern, and to estimate the effectiveness of specific marker designs in deterring intrusion and communicating a warning to future generations about the location and nature of the waste buried at the WIPP. The assumption was made that when individuals know what materials are buried in the area and the dangers of intruding into the material, they will not do so.* > > > * There is an excellent [bibliography with on-line links](http://www.oecd.org/officialdocuments/publicdisplaydocumentpdf/?cote=NEA/RWM(2011)13/REV4&docLanguage=En) titled "Preservation of Records, Knowledge and Memory Across Generations" and prepared by the Nuclear Energy Agency Radioactive Waste Management Committee of the OECD. * You may want to watch the excellent documentary [*Onkalo into Eternity*](https://www.youtube.com/watch?v=5HArxuzs1AA) about the design and building of the Finnish [Onkalo](https://en.wikipedia.org/wiki/Onkalo_spent_nuclear_fuel_repository) spent nuclear fuel repository. (And [high-definition version](https://www.youtube.com/watch?v=wke01P0rz2Q), unfortunately with hardcoded Romanian subtitles.) [Sandia National Laboratories'](https://en.wikipedia.org/wiki/Sandia_National_Laboratories) "Expert Judgment on Markers to Deter Inadvertent Human Intrusion into the Waste Isolation Pilot Plant" contains two appendices, Appendix F and Appendix G, describing the markings proposed by two different teams of experts labelled "Team A" and "Team B". * Team A, led by Kathleen M. Trauth, found that > > *[The] basic principles to guide current and future marker development efforts [are]: (1) the site must be marked, (2) message(s) must be truthful and informative, (3) multiple components within a marker system, (4) multiple means of communication (e.g., language, pictographs, scientific diagrams), (5) multiple levels of complexitiy within individual messages on individual marker system elements, (6) use of materials with little recycle value, and (7) international effort to maintain knowledge of the locations and contents of nuclear waste repositories.* > > > *The efficacy of the markers in deterring inadvertent human intrusion was estimated to decrease with time, with the probability function varying with the mode of intrusion (who is intruding and for what purpose) and the level of technological development of the society.* > > > Their idea was to use massive earthworks to convey the importance of the site, and multi-language durable inscriptions to convey the actual message: > > *The central area of interest is surrounded by earthen berms. For the WIPP site, the area of interest is where we do not want drilling or excavation to occur. In the design the central area is the area of the underground panels plus either (1) a one-fourth-mile buffer zone, or (2) the distance to which the radionuclides may migrate during the 10,000-year period, whichever is larger. The forms of the earthworks are jagged and rough, suggestive of energy radiating from the central area. The berms serve several purposes. First, they define the area of interest. Their size is set so that sand dunes are unlikely to cover all of them entirely at the same time. Instead, the wind will leave dunes streaming behind the berms and create an even larger marker.* > > > *Second, their shape sets the tone for the entire landscape -- non-natural, ominous, and repulsive.* > > > *Third, the corner berms are higher than the others and provide vantage points for viewing the entire site.* > > > *Fourth, the comer berms also include buried rooms with all the message levels recommended for inclusion in this marker system. As the berms erode, these rooms will become uncovered at various times. The investigator will be guided toward the center of the site by the berms. Prior to entering the central area, however, he or she will encounter a “message kiosk”. Each message kiosk is composed of a message wall and a protecting wall. In terms of site layout, the message kiosks form the only “nurturing” part of the marking system design. The protecting wall is of concrete and is meant to protect the message wall from erosion. The message wall is of granite or other hard rock and is a vertical, curved form. There are two reasons for a curved form: (1) it makes it very difficult to reuse the piece for another purpose, and (2) it is not an honorific form such as an obelisk. The vertical aspect minimizes tensile stress on the components.* > > > To solve the problem of the perishability of language, Team A came with an ingenious solution: the multilanguage inscription is to contain *blank spaces* where future generations should inscribe the same message in their language; and in the text of the message is to be written: *"If the marker is difficult to read, add new markers in longer-lasting materials in languages that you speak"*. * Team B, lead by David B. Givens, came with two interesting opinions; first, the scale of the marking system should be kept with human grasp, and, second, there should be a uniform international system of marking, in order to increase the chances of correct understanding. Specifically, they proposed: > > > + *(A) Berms or earthworks to help define the perimeter of the surface area directly above the waste repository. The earthwork might be arranged in the shape of a symbol, yet to be determined.* > + *(B) A ring of granite monoliths, around or within the perimeter of the marked area, bearing a variety of symbolic, pictographic and linguistic inscriptions.* > + *(C) A central granite structure to house more detailed textual, narrative, diagrammatic and scientific information.* > + *(D) A large number of small, durable markers inscribed with basic warning information, seeded at various depths within the marked area and in the surrounding earthworks.* > + *(E) Buried duplicates of the granite monoliths placed in key locations at various depths, such as in the plugs of sealed airshafts.* > + *(F) A layer of contrasting dielectric materials at the surface to permit remote detection by radar (perhaps arranged in the shape of the designated marking symbol).* > + *(G) Duplicates of markers placed in Carlsbad Caverns and in off-site archives.* > They even proposed the inclusion of a system of pictographic definition of conventional symbols, to increase the chances of understanding by future archaeologists. [Answer] **Where have I heard this before ?** Sounds something like the plot of practically all the *Indiana Jones* movies, not to mention *The Fifth Element* and, well, lots more. **I doubt this is possible.** > > Using only Aztec or Ancient Egyptian level technology, how could the race warn the future not to mess with the evil being's prison in a way that would last an absurdly long time (let's say for simplicity it needs to survive 100,000 years) that can be easily comprehended by anything and anyone, considering how much language changes in only a few thousand years. > > > The first problem is that an race with that level of technology would have no way of knowing how long a material or structure would survive. Even the concept of wear and tear, weathering and corrosion over such large time scales would be beyond their ability to estimate. It's doubtful the concept of a time scale that long would meaningful to them. It's doubtful *we* could make a structure that would last that long. To put this in perspective, the oldest known structure is about 7000 years old (less than a tenth of your goal). It's worth reading [it's history under modern man to get a feel for what happens old structures](https://en.wikipedia.org/wiki/Barnenez#Recognition_as_an_ancient_monument). **Doggerland** Making this even more challenging is that over the course of such a long time scale, geography changes in quite considerable ways. The best example is [Doggerland](https://en.wikipedia.org/wiki/Doggerland). Until about several thousand years ago there was no North Sea and you could walk to France from the UK ! This is the kind of change that can happen in thousands of years, and the kind of changes your builders would have no comprehension of. Anything they build could be made a mockery of by geology and time. **Some psychology.** Take a container about the size of a biscuit tin. Bring it to work and put a large sign on it saying "do not open - deadly snake inside". How long do you think it would be before someone decided they had to know if there really was a deadly snake inside and that opening it was the best way to find out ? People are curious and telling them they can't open something to see for themselves is just asking for trouble. Now let's apply this to your mysterious prison. Over the course of 100,000 years it is *inconceivable* that no matter what you say about what's inside, someone won't open it up. And that's assuming they actually understand your warnings. And that's not new. The people in your story planning to build this would know that as well - it would be a fact in their day as much as in ours. So ... > > Let's say that an ancient race of beings locked away some sort of evil that could destroy the world if unleashed. Let's also say that unleashing it would be relatively easy to do if not warned of danger. > > > So whatever you do you need pictures. Rock, to anyone of that time, lasts longest and they'd use the hardest rock they could. They use redundant messages, repeats in all the languages they knew and all the painting they could. When I say rock, I means lots of rock. Mountains of rock. Covered in more rock. With clay and earth and sand and lots more rock. And they'd create a group that was dedicated to passing the knowledge down from generation to generation. And, like all who tried that before them, it would get muddled and fail. The stories would become myth and legend in time. Few would believe them and those that did would be considered a bit whacko - the tin foil hat brigade. But if someone *did* believe these horror stories, there's one last bit f psychology to consider : *Some idiot would actually want to unleash the horror.* So, even if they succeeded in warning people, over the course of 100,000 years some group is going to open it either due to curiosity, stupidity or because they want to see the world burn. [Answer] Genghis Khan's tomb has not been found. He requested that, so they made a deep hole, placed him in then put back the ground, didn't put any sign and story says that they went with their horses in every direction, trampled earth both while going to the dig site and after finishing the burial going away. And did that so randomly that after time passed it was impossible to trace them back. If you want to keep something hidden, don't put signs saying "don't open this", put it somewhere no one can find it. It is generally a Hollywood go to stupid plot this thing of "warnings from the ancients". When people want to hide something or keep it away, they do just that, they don't make it easy to find and then write "don't look inside". So my question is: is it so important for your plot to have them write something there and so perpetuate a stupid stereotype or you can concentrate your story on the actual building of the tomb and on its secrecy? Because if you don't concentrate on writing useless stuff, you can make it simple by creating a stone prison and then bringing mud and dirt and planting trees and so creating a "natural" looking hill. Like the Chinese did with their pyramids, but in your case it would be an intentionally forgotten, never spoken about place. And the release of this ancient evil can be done by accident (your present time civilization can dig a tunnel there for a highway or whatever). [Answer] Keep the knowledge alive. Aboriginal Australians have traditions that correctly mark sites that haven't been above the ocean for ten thousand years. Some of their religious sites have evidence 40,000 years old. But that's not enough. A lot of the reason they have been able to do this is because no one else really bothered them for a long long long time. Once outside people started coming it didn't work out as well. Most famously a big red rock in the middle of a huge desert featured in lots of postcards isn't supposed to be climbed, taking a piece of it carries a curse and even photographing some parts is forbidden, but more than 100000 people climbed it last year and the Australia postal system continually receives souvenir pebbles from visitors hoping to uncurse themselves. You need to keep the religion powerful. A major religion has more than a 1000 year tradition of being at least locally powerful, of keeping exact traditions including reciting the main text in its entirety, and giving high importance to a particular place and objects. Exactly why it has been able to do this is harder to say. [Answer] **Use Drawings instead of Language** The [oldest drawings](https://en.wikipedia.org/wiki/Cave_painting) found are from 35000-40000 years ago. Drawings are universal. They transcend language. Even when language change, drawings and imagery doesn't. You can draw the prison. You can draw the evil beings. You can draw the consequences of opening up a prison. You can even draw starcharts to indicate years/time passing. [Answer] Many answers have discussed ways to keep people out by combinations of persuasion, force, and hiding.  I had less well developed versions of a couple of these ideas (e.g., pictographs — see also [my comment here](https://worldbuilding.stackexchange.com/q/105852/20215#comment320936_105912)), but here’s one that that I didn’t notice in any previous answer (sorry if it’s there and I skimmed past it): Obviously, beyond a certain point, you want to make the area hard to enter, to protect against people getting too close by accident.  (Other answers have suggested having a large surrounding buffer zone that is hard to damage but easy to enter, and using it as a repository for information and warnings about the danger.)  But, starting at or beyond the inner perimeter, where you don’t want people to enter, make it obviously *hard to **leave***.  Make it look less and less like a fortress or a bank vault, that might be guarding something valuable against intruders, and more and more like a prison that’s keeping something in (and protecting the outside world from the prisoner).  Some specific ideas: * Have the “prison” area at a lower level than the surrounding ground (i.e., in a pit) with smooth, vertical walls.  This concept has been used for many years to contain bears and big cats in open-air enclosures in zoos.  This is what such an enclosure looks like under construction / maintenance: [](https://i.stack.imgur.com/rKGCx.jpg "tiger enclosure (at San Francisco zoo?) under maintenance") [[Source]](https://www.konpax.com/san-francisco-zoo-tiger-mauling-2007 "tiger enclosure (at San Francisco zoo) under maintenance") [[Click to see larger image]](https://i.stack.imgur.com/rKGCx.jpg "tiger enclosure (at San Francisco zoo?) under maintenance") This is what it looks like in normal use: [](https://i.stack.imgur.com/paZH6.jpg "tiger in open-air enclosure in zoo") [[Source]](https://photos.tow.com/Autumn-Gem/Touring/Chicago-Illinois/i-cXMPkvR "tiger in open-air enclosure in zoo")  [](https://i.stack.imgur.com/YeUoQ.jpg "bear in open-air enclosure in zoo") [[Source]](https://designingzoos.com/2008/07/10/a-quick-lesson-in-zoo-design-history "bear in open-air enclosure in zoo") And this is what happens when it’s built to inadequate specifications: [](https://i.stack.imgur.com/00CP6.png "tiger jumping out of open-air enclosure") [[Source]](http://www.plaintiffmagazine.com/item/the-san-francisco-zoo-tiger-escape-and-attack "tiger jumping out of open-air enclosure") * Have doors that are apparently locked from the outside, like [](https://i.stack.imgur.com/YjoFB.png "door with “Zombie Bar”") [[Source]](http://zombie-bar.com/installation.html "door with “Zombie-Bar”")  and [](https://i.stack.imgur.com/1HNTx.png "door jammer") [[Source]](http://safetyed.org/browseproducts/Big-Jammer-Door-Brace.html "door jammer") Transparent doors will let people see that the locking mechanisms are primarily designed to prevent the door from being opened ***from the inside***.  It’s OK if these doors are, in fact, *also* hard to open from the outside; e.g., with locks holding the locking bars in place. * Have weapons *aimed toward the inside.*  Based on the constraints of the question, these would probably have to be passive defensive weapons (unless you believe that the *Indiana Jones* movies are realistic); something like spears or spikes: [](https://i.stack.imgur.com/ATHER.png "battlefield with barricade with spikes") [[Source]](https://trick-of-last-day-on-earth-survival.br.aptoide.com "battlefield with barricade with spikes")  [](https://i.stack.imgur.com/7bnYR.png "another battlefield barricade with spikes") [[Source]](http://ovor.co/spikes.html "another battlefield barricade with spikes")  [](https://i.stack.imgur.com/S7jyS.png "spike strip that damages tires") [[Source]](https://www.lockharttactical.com/product/product/8609860-low-profile-electric-barricade-section "spike strip that damages tires") pointing toward the inside. It’s not important that any of these actually be appropriate for or commensurate to the danger that’s within; it’s only important to convey the message that the builders of the prison thought that the demon was dangerous. There’s a concept in physical security of “security in depth”: protecting physical assets with locked doors, fences, human guards, dogs, motion detectors, etc.  Computers have similar layers of defense, such as firewalls, compartments, containers and domains.  This answer represents an “in depth” approach to the psychological aspect of this problem.  After 99+ millennia, the best schemes for documenting the evil may break down.  Even if the warnings are understood, some people will defy them, perhaps believing them to be a deception, intended to keep people away from something valuable (like the warning signs that muggles see when they approach Hogwarts).  The techniques described in this answer should be easily understood 100K years from now, and might convince people who (willfully or otherwise) are not deterred by the other warnings. [Answer] Over a hundred thousand years, civilizations can raise and fall many times. In times of low to middle civilization, the "protected vault must mean treasure" reflex will overcome any message you may leave. Only in highly civilized times will people even *look* at the message before fetching their pickaxes. And the ancients knew this. ## Make it inaccessible To protect the vault in bad times, make it inaccessible without high technology. Since you have limited the technology of the vault builders, I see only one way they can do that: **Dump it in the sea.** They would need a prison that is small and light enough to fit on a ship. They did *not* need to be able to actually toss it overboard as they can sink the whole ship. One can only hope they brought another ship to bring the crew back. Ships at the time weren't very sea-worthy so they could not go very far from the coast. This limits the depth you can dump the thing. There is also the risk of the land rising and exposing the wreck and the vault. If, for example, they dumped it in the Mediterranean Sea and the Gibraltar Strait closed, lots of sea bottom would become dry land. Let us assume that the ancients foretold a time would come when people would be able to get at the thing, so they still left a message for the future. The only symbol for death and danger that is truly timeless is skulls and skeletons. Engrave the thing with lots of skeletons. Many enough that people understand it doesn't mean "contains skeletons" but "causes skeletons, lots of skeletons". ## Write it up One of the technologies Egypt had was writing. Write up the story of how the Big Bad was captured and imprisoned. Describe the prison in enough detail that people will recognize it when they see it. Do *not* write down where to find it, since there is always that one idiot who will go looking. "Dumped at sea" is enough for that part. Make as many copies as you can, translate into as many languages as you can, spread the word! Make the copies as durable as possible. That means stone engravings in protected locations. Pray that people will keep spreading the story without too much distortion in the millennia to come. Speaking of praying, this story will probably spawn a religion. This is both good and bad, as religions are good at keeping stories alive, but very bad at understanding and interpreting them. Translations done by religious people will tend to distort the story towards what is the accepted theological truth at the time. [Answer] Considering if you show humans a big red button and tell them not to ever press it, under any circumstances, you will find the button being pressed within 2 minutes: Do Not Warn Them! Sounds nonsensical, but is making the place where the Big Bad is locked really really really uninteresting, out of the way and very boring an option? In addition, you could leave interesting but less dangerous things around, and warn about THOSE! Hopefully, this will gain you the required timespan. [Answer] **Salt the earth.** > > Judges 9:45. > > And Abimelech fought against the city all that day; and he took the > city, and slew the people that was therein, and beat down the city, > and sowed it with salt. > > > A warning will bring adventurers. Dead kings post curses all the time to keep away tomb robbers. Any sign of ancient works will get people interested. Maybe inside there are relics? Pieces of metal? Someone was here long ago, and cared enough to build something and maybe that building contains something I can sell, because I am hungry. In ancient days, conquerors salted the earth to symbolically drive a stake through the heart of the conquered place. For your needs, evidence that there is poison in the ground will keep people clear. The ground should be poisoned so nothing will grow, ever. There should be no symbols, buildings, signs or anything else. The lack of life will be the sign that this is a bad place for life. Later peoples may or may not know that the toxic place is the doing of people who came before. They might think it is something natural - good. If there is no evidence of ancient artifacts there is no reason to look for treasure. If nothing grows there is no reason to look for food. If it seems like it is poisonous there is good reason to stay clear. [](https://i.stack.imgur.com/ILwBI.jpg) <https://www.theguardian.com/environment/gallery/2015/apr/15/rare-earthenware-a-journey-to-the-toxic-source-of-luxury-goods> [Answer] If you want some ideas, look up how modern governments are trying to secure nuclear waste dumps for similar time spans. Written warnings and pictographs will be no use at all, because no language will survive that long and there is no guarantee that people will understand a warning symbol. The best Idea is to try and make the area as inaccessible as possible whilst also trying not to make it look like there is something valuable hidden there this [article](https://www.damninteresting.com/this-place-is-not-a-place-of-honor/) describes the current thinking > > Ultimately, the decision for the WIPP markers was motivated by cost-effectiveness. Current plans call for the area over the waste storage panels to be outlined by “earthen berms,” which is another way of saying “large piles of dirt.” These berms will be jagged in shape and will radiate out from a central, generally square area. The jagged nature of the berms is meant to convey a sense of foreboding, and the exact size, shape, and configuration of the berms will be such that they will not quickly be eroded or covered. The four corner berms will be higher than the others to provide vantage points to see the area as a whole. Inside the corner berms will also be buried concrete rooms containing highly detailed information, such as maps, the periodic table, and astronomical charts indicating the date that the facility was sealed. This data will be engraved upon stone slabs which are too large to be removed from the rooms’ entrances. > > > [Answer] who's to say ancients haven't done this, we have Egyptian hieroglyphs and we have stories about their mythologies, a good myth can have morals or warnings of things to avoid [Answer] How about a set of huge tetrahedral monoliths in the pattern of the constellation from which the danger came (maybe with square bases for better stability though). Oh wait.. [Answer] First @Alexp has some good ideas listed but I am going to take a different perspective. Pretend you bury the ancient evil in 5000bc, and evolution occurs at the same rate and we end up where we are today in terms of technology. **In the last decade or so sapphire disc have been developed that last 100,000 years and all you need to read them is a microscope.** Once you reach 2017 you can make copies of the sapphire disc for about $200-$500. This means making 10,000 copies and storing them all over the world is no problem at all. You can engrave something like 10,000 pages of text, enough to record it in every known language and in countless derivatives of said languages. This means our **real** problem is only from -5000 to about 2017, and visiting the worst case scenario the year 3000. So a max of 8000 years instead this 100,000 year business. **By the year 3000, or before we should be able to bundle up said evil, and launch it into the sun, or if it can absorb energy to live then mars, pluto, or etc. Then if it escapes those planets are already destroyed and life less so who cares.** Today we have radar,lidar, and even muon detectors to map out the structure, and the nature of said ancient evil so we will be able to know a lot about this ancient evil and how to contain it. Also any information recorded today is unlikely to ever be lost with the exception of a extinction level event. So once we launch the ancient evil into outer space we can stop worrying about it because we won't be able to reach it at all if we have an extinction level event. So starting in 5000bc you will have to have an active civilization around this tomb, for lack of better word, to maintain it as long as possible. As **Alexp** mentioned large curved stone tablets with writing and room to re-write it every 10-50 years or as necessary to the language changes. The writings will have to be interior and exterior, but I expect most of the exterior writing to erode over time. The structure will have to be many times thicker than necessary to allow for erosion. If the air gets polluted and/or has too much moisture erosion will happen many orders of magnitude faster than you initially planned for. You will have to have a civilization build a city around/near it to guard it on all sides. Like a cult or religion that passes their beliefs on from one generation to the next. They will have to convey the warning to all those that approach. They will have to transcribe everything into all new languages and etch that into new stone. Also make books when they are eventually invented. Your best bets are to bury it deep within the sand,water, ice shelf, lava, or perhaps arrange avalanches from a nearby mountain to truly bury it. 1-2mi deep, water, even a lot less than would be completely inaccessible. Ice even 200ft deep, even today we don't dig that deep in ice, except maybe a few ice cores. So hopefully your cult, and burying it will last you till 2017 at which time you can probably launch the "evil" into outer space. [Answer] ## Damage or hurt slightly anyone approaching the site Besides the warning signs/monoliths (which may be dug out by archaeologists several thousands of years later, even if they depict warnings), there could be a non-deadly trap system that would **hurt the intruder physically and/or psychologically**. A couple of examples: * archaeologist approaches one of the entrances of the complex and a trap door/step would simply make him fall on the ground where solid and heavy rocks would depict deeply carved dead or suffering animals/beings; * drone approaches the place and a certain semi-closed area would have a magnetic/electric field (or radioactive material?) that would disrupt electronics and once it passed through, similar rocks from above would be seen. Supposedly [Egyptians had some knowledge about electronics](http://enigmose.com/electricty_ancient_egypt.html), therefore with a big enough battery *zapping* them could also be a way to scare off primitive animals as well. [Answer] > > that can be easily comprehended by anything and anyone, considering how much >language changes in only a few thousand years. > > > First of all, it would be impossible to create a universal message to include "anything" because you have to start with some commonality. Assuming the ancient and future race are both human and only the normal 5 senses available (no esp) then the message will be visual. The prison should have an obvious entrance marked with a symbol on the door. In a three panel image, Panel 1: Show the closed door with symbol, several people and animals. Panel 2: Show Person open the door. Panel 3: Show open door and skeletons of humans and animals to indicate death. [Answer] I have not seen it yet but its mostly an augment to the "leave no trace" suggestions that appear. To keep something from being opened would be to remove it from existence. Not in the literal way of course but in everything. It must be wiped from texts, myths and legends so no trace of it remains. Everything leading up to the event must be expunged so that there is no "sudden dead end" in texts a la "there is a page that is missing" trope. Even if the place is opened and the object found, don't make it look different than everything else. that makes people go "ooh, it says not to open it but it's the only container with writing so lets open it." If some destroyed city plays prominently into the how it happened, take it apart and use the stones for something else like building a wall around a city or some such or if it can't be safely re-used for permanently structures, move the city. The easiest example that comes to mind is as mentioned previously regarding the tomb of Genghis Khan where the workers were killed by the guards who reported their success to another group of guards who killed the first set of guards. This effectively hid the location of the tomb to this day. Of course, we know about it so part of this explanation is already compromised which is the "this page is missing" part you are trying to avoid. It could be taken a step further by creating some sort of group that scouts that spot but also many others to help throw people off. They don't have to look like soldiers or warriors outwardly but they must be ready to ward people off who stray or stay too close. An example that comes to mind would be the Medjay from The Mummy (1999) which did a terrible job since they would loiter near the hidden city all the time leaving a marker so to speak but the premise is sound. I suppose though that this does not serve the purpose of your request as to warn people so I apologize if this is lacking any assistance. [Answer] The obvious thing is Locks an/or puzzles, Some things like having various artifacts that must be used together to unlock it, so while it's easy to unlock with all the "keys" without those it would be very hard. The same with a puzzle in order to understand the puzzle you may need some context about the ancients, once you have that context you would know that opening it would be unwise. Things like language, so in order to understand the puzzle you would need to understand the language and once you understand it you would have the knowledge to be warned about opening it as well. Just some thoughts. [Answer] drawings would last a long time, especially in a cave. drawings are universal so that is the best option. they would have to make a lot of drawings though to convince the future of the danger. [Answer] There's probably a formula to back this up, but as a rule, the amount of insistence made not to do a thing (Don't go there, Don't open that, Don't touch that, What did I just say?) Is in inverse ratio to the attention paid to said warnings by later generations and civilizations. One of the most fraught with portent sentences ever uttered is "Oh, it can't be THAT bad..." [Answer] There is this theory in acoustics, that if malleable material like clay is exposed to sound, it creates minute vibration marks on the object which can be read with specialized instruments. Therefore, a Morse code message embedded in a clay disk might just work. ]

[Question] [ Inspired by today's [XKCD](https://xkcd.com/2038/) comic [](https://i.stack.imgur.com/fGOu8.png "The warning diamond on the Materials Safety Data Sheet for this stuff just has the \"üò∞\" emoji in all four fields.") How could a creature, momentarily called *XKCDius lethalissimus*, evolve to have the following features: 1. Be radioactive (intended as more radioactive than the environmental background) 2. Give high voltage hazard 3. Emit laser 4. Be a biohazard 5. Be slimy enough to make a floor slippery If laser emission is not feasible, I can settle for just incoherent light emission. This is my contribution to the [Anatomically Correct](http://meta.worldbuilding.stackexchange.com/questions/2797/anatomically-correct-series/2798#2798) series. [Answer] I can see evolution provide 1, 2, 4, and 5. 2, 4, and 5 all occur in nature now. 1 could be explained by other means. We are going to have to stretch to get the laser working. As a base creature, we could start with some sort of Amphibian. Most Frogs, newts, salamanders and such can produce mucus of varying properties. One of them, in the case of poison dart frogs, is a strong alkaloid toxin. That gives you a bio-hazard. A big frog could also give your slip and fall hazard by leaving the mucus all over and if it doesn't evaporate quickly, you could step on a patch and take a tumble. So getting 4 and 5 together is pretty plausible. Your evolutionary justification for this is some sort of boundary between a swamp and desert. Most likely in a river delta. The massive mucus production helps keep the Amphibian moist when a dry spell or hot wind from the desert threatens to dry our little friend out. The Toxin, and probable colorful markings, would be a warning for any birds that may view him as a tasty snack. 'Eat me, and you won't live long enough to reproduce' Moving on to number 2. The Voltage hazard. Electric eels hunt by giving a stunning shock to their prey. Lets start with that, and have our little buddy evolve from an electric eel, keeping that electrical charge as its prime hunting mechanism. Remember, cute frogs are actually predators. With a stout shock, a frog may be able to take prey nearly as large as itself a little easier. So keep that mechanism as an evolutionary holdover. That's 3 down, 2 to go. Number one on your list, Radioactivity. Higher than background. Here is how we get to that. A little farther up the river there is a mountain with large deposits of Uranium. Rain and erosion wash a lot of this naturally occurring stuff downstream, where it settles deep in the delta where our little *lethalissimus* lives. He's going to absorb a lot of it as a function of his environment. Granted, it will match the background radiation of the swamp itself, but out of the swamp, his personal radiation will be relatively much higher. However they could also have a form of body chemistry which bio accumulates some of the radioactive daughter products; say strontium-90 phosphorous based bones. Due to higher availability of strontium vs calcium in that environment. Finally we get to the lasers. *sigh*. I can't think of any way to produce a natural laser. Fortunately, you left me an out for light emission. Bio-Luminescence. Fireflies do this to draw mates, angler fish do this to draw prey, and so on. So the electric eel that is the forebear of our friend shared some traits with an angler fish with a lure to draw prey into electric stun range at night. So what we end up with is a large Frog-like creature. Brightly colored with an appendage on either side of its body with a bioluminescent sack to draw prey, like a small bird, into stun range. Bird goes for glowy thing and gets zapped. During the day, other birds get discouraged by the brightly colored pattern that says 'stay away unless you want a terminal tummy ache' due to the highly toxic function of the mucus. The Mucus is produced in large quantities to help keep him hydrated in hot weather. The slow evaporation means slick surfaces every where he goes. And he is Radioactive merely due to the runoff from Mount Plutonium, and bio-accumulation of radioactive elements. [Answer] [](https://i.stack.imgur.com/6ucJX.jpg) [source](https://www.telegraph.co.uk/news/uknews/law-and-order/10298378/Police-use-of-Taser-stun-guns-doubles-in-two-years.html) * high voltage: check * laser: check * slimy: wait till you meet him. * biohazard: he has scabies. * radioactive: he wears a watch with a radium dial. Evolved to have these abilities: it must be the case, because here he is. [Answer] Start with the [black radiotrophic fungus that thrives in Chernobyl](https://en.wikipedia.org/wiki/Radiotrophic_fungus). It is easy to conceive a drippy, slimy fungus that will cause the floor around it to be slippery, as well as being a biohazard due to the symbiotic bacteria it harbors. In order to give you a jolt, it will need to have [electroplaques, just like a unicorn](https://worldbuilding.stackexchange.com/a/109216/21222). It could have those in the fungal body, evolved as a defense mechanism against animals that would eat it. Finally, lasers. There is no way to have those with known biology. But the fungal body may be somewhat translucent to some wavelengths, and act as lenses - specially if the fungal body accumulates silicon and oxygen in just the right way. If you chop it and place it on your backyard, it might even act as a [magnifying grass](http://plantsvszombies.wikia.com/wiki/Magnifying_Grass) and set the lawn on fire, adding one more hazard to the package. --- Alternatively it does not work as lenses nor give out lasers at all. But if it is a mushroom and there are humans around, regardless of its hazards it is just a matter of time until someone eats it. It may be that anyone crazy enough to ingest it will hallucinate and see lasers and other forms of light. The fungus will be known as lasershroom, and will be a favorite amongst the most suicidal psychonauts. [Answer] This is just a **sanity check** of how each attribute could be achieved. Not a proposal of a full functioning organism. I am only providing a *sanity check* because I do not think this organism would ever evolve. The key reason is that this animal has at least 3 completely separate defense mechanisms, that traditionally use up almost all of an animals body space and resources. Normally evolution would favor making one of these really good, over having all 3. Even if all were effective and dangerous, it would be wasteful to the animal and its species because it is unlikely that all these defense mechanisms would be required for successful *survival* and *reproduction*, (the driving force of evolution). Never the less here are the desired qualities and real life examples. We can mix these together to make the desired organism, and research how these came to pass in order to make up a contrived case for the evolutionary history of this organism. **Be radioactive, more radioactive than the environment** : This can be done by having the animal require a large amount of potassium as part of its diet. You can see this in plants with naturally elevated levels of radioactivity: <https://www.mirion.com/introduction-to-radiation-safety/naturally-occurring-radiation-norm/> **Give high voltage hazard** : Evolve an electricity producing organ like the electric eels Hunter Organ : <https://en.wikipedia.org/wiki/Electric_eel> **Emit laser** : This one is probably impossible. At least if it is intended to be dangerous. Of course since a laser is just a focused beam of light, we could pick at the question and create a faint light source that is simply focused, but this seems to be against the question's intent. Either way, bioluminescence is the best we are going to get. There are too many things that are no goes here for a dangerous laser. How do you store up so much energy? Is using a laser just an incredible waste of resources? Would this ever actually evolve? I think it would not at all, and certainly not on an organism that already has other defense mechanisms like those stated here. **Be a biohazard** : As others have stated, be toxic. Like various species of poisonous tree frog, salamander, etc. **Slimy enough to make a floor slippery** : Snails are the go to here. Just have a mucus membrane interacting with the floor. In the case of snails it is for sticking. It could be the same here. [Answer] All you need is a glowing, shocking banana tree. Be radioactive – they are already more radioactive than background radiation Give high voltage hazard - this is the tricky one but using info from [this WB answer](https://worldbuilding.stackexchange.com/a/100317/46918) we know it's possible for organic photo-voltaic conversion so all the plant does is convert excess sunlight into electricity which it stores for future use (or to power its bio-luminescence) Emit a laser - since you allowed bio-luminescence we have enough plants to adapt this from. Be a biohazard - make it poisonous Be slimy enough to make a floor slippery - have you seen a mushy banana ? [Answer] Three out of five are pretty easy- slippery, electricity, and biohazard. It'd be pretty easy to concoct an animal that could satisfy those conditions, as they already exist in nature. Something like an electric eel that also has venomous fangs would serve pretty well. However, radioactivity and lasers are much more difficult. While radioactive isotopes of common elements do exist, they're generally found in very small quantities, and there's no way to chemically distinguish them from stable isotopes. So your eel wouldn't be able to, say, accumulate carbon-14 somehow. Collecting quantities of an unstable heavy element would seem more plausible- there are ongoing experiments with extracting uranium from seawater, for example, so a living creature might be able to do this on its own. However, naturally-occurring uranium is really not that radioactive. In fact, the only way it can really be dangerous is if it's ingested- not because of the increased exposure to alpha particles and such, but because it's toxic and can cause kidney failure. Even if your animal did somehow isolate it in a special organ, all it'd do is increase its own cancer risk, with no discernible evolutionary benefit. Even if we assume that there's somehow a large natural source of some short-half-life element that this creature feeds on, it would cause far, far more harm to the creature itself than to any predators or prey. Letting highly radioactive substances inside your body is never a good idea. As for lasers... as Paul TIKI mentioned, probably the closest you're going to get is bioluminescence for purposes of luring prey. [Answer] # Adult Lightning Unicorn [This is not the first answer I've written about Lightning Unicorns](https://worldbuilding.stackexchange.com/questions/109199/how-do-i-explain-a-unicorn-discharging-powerful-electricity-at-a-distance/109214#109214), but TLDR they fire lightning along a laser channel. During the refractory period after firing their laser the Lightning Unicorn absorbs ambient heat at a prodigious rate. This temperature drop generally causes condensation in the immediately area. In a meadow this leaves a large dewy area, often thought to have mystical properties, in addition to the slip factor. And of course everyone knows that the Lightning Unicorn's horn laser is a Nuclear Pump laser, so extended proximity should probably be avoided. [Answer] Did you mean [Dripping Bonnet?](https://en.wikipedia.org/wiki/Roridomyces_roridus) So as it turns out, there's already a species that essentially meets all your requirements. In specific, the [Roridomyces](https://en.wikipedia.org/wiki/Roridomyces) genus of Fungi seems to contain a lot of the requirements but Roridomyeces Roridus, or dripping bonnet, has the most in one place that I can find. Let's go down the list one at a time. * Radioactive: Now, all species tend to have some amount of potassium inside their cells. In the case of dripping bonnet, there isn't necessarily a higher concentration then most other plants, but one growing in a potassium rich soil could easily be classified (as very very slightly) radioactive. * High Voltage: As it turns out, all plants are high voltage. Yes, I know it sounds weird, but hear me out. You know that potassium that all plants have from the Radioactive portion of my answer? Well potassium is used inside plant cells to create an ionic difference between the inside and outside of the cell. That means plants can use it to deploy small [electrical impulses](https://www.ncbi.nlm.nih.gov/pubmed/17263772). The debate over what these impulses do is still ongoing, but by their nature as static electric fields, they *may* be considered high voltage. I am having trouble figuring out how to properly calculate voltage, but I do know the resting voltage between cells is 70 mV, with each cell being around 10 Micrometers. * Emit Lasers: Turns out these little guys are Bioluminescent. Now, I know that that's not technically a laser, but lasers don't exist in nature, so light emitting is pretty good all in all. It's been suggested that the luciferin which makes the bioluminescence happen, can actually be used as a liquid laser substrate. If the cone can be considered a collimator (albeit a poor one) that makes a mushroom kind of like a laser, depending on the frequency emitted by the luciferin. * ‚ò£ BioHazard: Unfortunately, our mushroom fails to pass the biohazard test. Simply put, they aren't designed to infect humans. Sure, a sick human may be able to contract them, but a biohazard is typically considered an infectious agent that can infect a healthy human. * Slimy: This is the big perk of Dripping Bonnet, it secretes a sticky liquid. They're pretty small, so it probably rarely happens, but a grouping of them could definitely make a slippery spot on a floor. So there you have it, a single mushroom already meets four of five criteria. However, Biohazards are hard to find, considering toxins usually end up classified as a Hazard rather than a biohazard, according to UN Standards. Fungus are one of the few biohazards that aren't either viral or microbial though, so that at least puts it as close as possible. [Answer] As others have noted, you are basically searching for a poisonous frog which hunts using electric shocks like electric eel do. I have an improvement to offer for the light emission (see note below) and radioactivity to add: The Lethalissimus has a special organ for its luminescence: It's a patch of skin on its back that both accumulates radioactive materials from a possibly already enriched environment, and which also contains a dye that turns the radioactive radiation into light. For the frog, this has the advantage that it does not need to expend energy to keep its light glowing, it just needs to accumulate enough material. The glowing is, of course, part of Lethalissimus' strategy to avoid predators: A visible yellow glow even by day should be enough to make any bird think twice about its choice of a snack... --- **Note**: Real lasing is pretty much out of the question. Lasers *require* very high power densities which are not found in biology. And small (= size of typical creature) lasers *require* a laser cavity between highly reflective mirrors, which are also not found in nature. There are really some quite strange creatures out there, but I'd find it hard to believe a lasing one to exist for these reasons. [Answer] Since the other aspects have been well handled already, I'm going to focus on the laser. Although lasers are not known to exist in the biological world, I think a biological laser might be possible. A biological laser would likely be similar to [engineered chemical lasers](https://en.wikipedia.org/wiki/Chemical_oxygen_iodine_laser "Chemical oxygen iodine laser"), creating excited states of molecules by chemical reactions. Your eyes have optical quality lenses, so focusing the beam should not be a problem either. [Answer] I can't imagine it actually evolving but I can see an evolutionary path: First, we need a young planet that condensed from a reasonably recent supernova. This is to produce a sufficiently high concentration of U-235 that natural uranium can sustain a chain reaction. (This happened a couple of billion years ago on Earth, thus it's possible.) 1) I do not know why the creature wanted a block of uranium in it, but for some reason it did. The climate turned too cold, it evolved to use a low grade fission reaction to keep from freezing--and developed enough radiation resistance that most of the creatures aren't killed by their reactors. This is also a major defense system for the creature--the creature controls the reaction to maintain fission at a low rate but if it's eaten the reactor might run hot--pretty dangerous to whatever was trying to eat it. 2) We already have the example of an electric eel. 3) There is another thread about biological lasers--but why? We don't need a weapons grade laser--our creature is an air-breathing swamp dweller. So long as the laser can ionize it's path it provides a way of projecting it's shock weapon a short range--the outgoing bolt follows the laser, the return path is the swamp itself. 4) Trivial--it's a carrier of something deadly. 5) It's skin needs protection from the drying air--plenty of such creatures are slimy. We have two spots that are going to be **very** hard to evolve--one would be very unusual, both in one creature probably would never occur. However, I wouldn't consider it utterly impossible. ]

[Question] [ In a lot of science fiction series, such as *Halo*, *Mass Effect* and *Gears of War*, they show alien technology that is flatly human with a few added-on bells and whistles. It lacks the awe or feel of truly alien technology. How can I make an alien civilization's technology, such as their vehicles, buildings and weaponry, feel alien and not like stylized human clones? [Answer] There are two fundamental problems # 1. Outside - Aliens are humanoid, more or less This is a big one. If aliens have the same basic build humans do, interfaces to their tech will be similar, too. We reached perfection in steering, input, output and so on. We are at the point where ergonomy has reached it's maximum and we tried everything we could think about in the way. That's why, for humanoid aliens, everything will look like human stuff, or retro-future. # 2. Inside - Aliens use the same physics we do And, to put it bluntly, we already tried everything that could work and more within the physics we know. Some things was better, some worse, but generations already thought of, and tried everything they could. --- Now, when we have reasons well defined, all you need to do is remove them, as deep as you can. 1. Outside solutions * Non-humanoid shape * Manipulators as far from hand-like as you can * Different main sense to eliminate screens * D'uh, make all senses different from ours * Make them resistant to some things that makes us ill * Make them feel sick from something that's OK for us (like bass sound of internal combustion engine) * Many of our tech is based on the fact we feel self. We feel units. We are separate beings. This may be different for aliens. (Thanks [Jim](https://worldbuilding.stackexchange.com/users/22778/jim)) 2. Inside solutions These are really, really hard. Can't change physics. Wheels will be wheels will be wheels, best tool to roll things around. * Give them materials we can't have, like room temperature superconductors * Change their environment, so they have different problems to solve * Handweave some important, basic principle of physics for them and build around that. * As [Jim](https://worldbuilding.stackexchange.com/users/22778/jim) pointed out [in his comment](https://worldbuilding.stackexchange.com/questions/60837/how-do-i-make-an-alien-technology-feel-alien/60841#comment173654_60841), you could remove human aesthetics - for this you need to remove need for symmetry (for us it's easier to build symmetrical craft), need for repetition (we need assembly lines), things like that. [Answer] ## Impossibly advanced technology First of all, the likelihood of the aliens being at a similar technological level of advancement as we are is basically 0, given the timescales of the Universe. Again, imagine how an Apollo Rocket would appear to Stone Age humans, or even better, to annelid worms (a mere 518 million years old, younglings in the history of even our galaxy). Repeating the Clarke mantra about sufficiently advanced technology, the physical causation pathways would appear utterly mysterious. Even if life is limited to evolve along similar pathways - Carbon and Water poor metallic-oxygen planets like earth, Carbon-based life using DNA to start, subject to the same apparent physical laws, hundreds of millions of years can refine their understanding of the universe, allow their civilization to transcend the limitations of DNA-replicators and thus change them beyond human recognition as a kindred organism. ## Reductionist metaphors fail I am instantly reminded of the book *Solaris* by Stanislaw Lem, which was made into a pretty good film by Andrei Tarkovsky. The alien in question is a planetary intelligence resembling an ocean of sorts. Human scientists had spent decades observing and categorizing the complex whirls and patterns exhibited on the surface without making any real progress in understanding it. It is incomprehensible, fluid. It modifies from afar humans' perception of reality to the point where it is unclear what is real and what is illusion, or even that there is any meaningful difference between the two. Any anthropomorphic metaphors fail miserably in interacting with the aliens or their technology. These are not Rubber-Forehead Aliens. If the aliens can bend space, even the local geometry could be non-euclidean. There is no mechanism to be seen, nothing subject-able to human's normal reductionist way of understanding reality. Moreover, since the technology is not designed with human UX in mind, it may/should interact weirdly with humans attempting to use it. A bit like the Obelisks and Reapers husks in *Mass Effect*. ## Incomprehensible Goals It may be that the Aliens function on [Blue-Orange morality](http://tvtropes.org/pmwiki/pmwiki.php/Main/BlueAndOrangeMorality), so their actions and goals, and thus the functionality of their technology literally make no sense to our minds. Our interaction with it could be similar to squirrels using roads and cars to crush nuts - a complete side-effect of the normal operation of (what is to squirrels) alien technology. [Answer] Alien technology is alien because the aliens are, well, alien. My favourite example from SF is the Martians from "[Last and First Men](http://rads.stackoverflow.com/amzn/click/0486466825)", a seminal work of SF from the 1930's. The Martians are particles the size of a virus which live in the upper atmosphere of Mars. They only become intelligent as they bind together into larger and larger groups, and their mode of life is gathering solar energy, so in their collective, intelligent form, the Martians resemble a sheet of organic material draped over a flat surface. In the book, they eventually drift through space to Earth in order to escape some sort of environmental issue on Mars, and are very pleased to find Earth has a *multitude* of flat surfaces to rest on. Oddly, it never occurs to the Martians to ask *why* there are so many flat surfaces on Earth.... [](https://i.stack.imgur.com/AiWPf.jpg) *Wow, this planet is the best.....* Based on that description, the Martians can know, understand and potentially make technology to use and manipulate the forces of nature, but they certainly will not be doing it through any means recognizable or usable to us. So the first step is to know and understand what it is that makes your species *alien* rather than people with rubber foreheads. Once you have that in hand, it becomes possible to consider how *they* would have to use technology to do things, which then becomes your alien technology. [Answer] First you should think about how you want your aliens to look and work. Are they bipedal with two arms and the head on top? They could have two strong arms for lifting stuff and a third, smaller, for fine manipulation. Perhaps the strong ones are tentacles, instead. Our main sense when piloting a vehicle is sight. Just by assuming that a certain species of aliens has poor sight their vehicles would have to be utterly different. Any fast moving thing would be impossible for them to pilot without sensors helping them. That would mean that they have no, or much less, use for windows. Instead they would use some kind of sensor array to help overcome that problem. Or they could have some radar like sense and have "windows" not made of glass but some material specially transparent to their sense/wavelength. By that humans could not pilot that kind of craft because they would not be able to perceive the surrounding environment. Now assume their bodies are accustomed to lower g forces. They could build their vehicles with more protection, perhaps have beds instead of seats. Most of our personal vehicles have a motor - passenger - trunk design with two seats front and two or more back and have similarities in height/length/depth ratio. The aliens could change that, too and build arrow shaped vehicles. Add a potential hovercraft design for exploration (they don't know in advance how planets they want to visit are accessible for tires). You end up with a windowless arrow shaped thing without tires, the front lower than the back. If the humans find an opening they see a tube and don't know whether to enter head first or feet first or whether the aliens are just very small. And if they enter the right direction they don't see outside and still don't know whether to lie face up or face down. And existing "light" could be of a wavelength invisible and perhaps even harmful to humans. [Answer] It is easy to fall into a stance of physicalist determinism where alien technology follows the same set of physical laws so it must be the same as human technology. But mostly it's a failure of imagination. First, to dispose of physical determinism. If this was truly so, then all technology would look exactly the same if it had the same function. Look at the nearest piece of technology. Say, your computer or mobile phone (more correctly, called a cell phone by Americans) and while certainly there are many technological similarities different brands have even specific quirks and features. Effectively every piece of technology is not merely shaped by the physical principles of its manufacture and its ultilitarian function, but cultural aesthetics and design also plays a major role. Technologies like aircraft and spacecraft are among our most highly functional and yet there are differences in style, configuration and appearance. These differences are as much as cultural as well as reflecting preferences in technical solutions. There are already major differences in the ways technologies are used and applied in current human cultures. They reflect the social, political, economic and cultural institutions of their nations. Compare the cultural differences between two relatively geographically close Asian cultures. The Japanese have a minimalist and often highly restrained aesthetic, while the Chinese make and design things with a gaudy and exuberant aesthetic. The difference is in part due to Japan being resource poor and China resource rich, and yet they share many similar cultural traditions their expression is different. Compare and contrast American and European aesthetic traditions as a Western example. Even humanoid aliens will have a multitude of cultural and aesthetic differences from Earth evolved humans, due to their distinct evolutionary histories, their social, economic and political institutions, their technology will have similar differences. Primitive humans in making artefacts as simple as stone axes displayed a tendency to go that extra bit further, in making them more symmetric than purely needed for their function. An alien humanoid might is likely to add either embellishments of the same kind in ordering the shape of a blaster to be more symmetrical or have it conform to some cultural imperative like, say, a resemblance to a sword due to its species' long historical tradition with sword wielding (this is a trivial and a not very alien example; but you should get the drift). Differences with non-humanoid aliens will be much more extreme. There will always be the same technical functions present in their technology, but their entirely biological and cultural histories will shape remarkably different perceptions. The style and use of their technology can be expected to be different. A blaster may still be a blaster, but its shape and form may be unlike a human-made blaster. For example, xenophobe aliens are likely to always shoot first. Since this might, traditionally, be only a warning shot, learn to duck first. One example of a TV show where differences in alien technology was commonplace, and not remarked upon, was *Babylon 5* where spaceships of every alien species was designed to be different. So different, that a viewer only needed to see a spaceship you know which species it belonged to. This approach can be used for guidance in designing the technology of an alien civilization. Devise ways their technology looks or works and make it distinctly theirs. Do the same for every alien civilization in your story too. This includes humans too, after all we're aliens from the perspective of the other, well, *aliens*. This works at the level of cultural aesthetics. The next step up the great chain of being is to try imagine alien civilizations with utterly superior advance technology operating on hitherto inexplicable scientific principles. Some of this technology may be explicable, in terms of humans knowing what it does and possibly how it does, but humans may still have no idea how to make it work themselves. For example, aliens with FTL spaceships while humans can see what is does without a clue how it does it. Other advanced technologies may simply do things without anyone having a clue how it does it. For example, "locking" humans out their solar system in some entirely inexplicable manner. (To cite another recent question here.) If you want to achieve alien technology that seems truly alien and awesome, be unafraid to use your imagination and to do it with style. [Answer] ## Change the primary means of interacting with the technology The most obvious way to make something appear alien to your viewer or reader would be to change the interface workings so that sight and (to a lesser extent touch) is de-emphasized, and bi-pedal hands-free locomotion is no longer the norm. Picture your humanoid scouting crew encountering the interior of an alien ship or surface habitation: No flashing lights (no lights at all), no buttons, no viewscreens. Howls, whispers and smells emit from protrusions all along the ceiling with weblike patterns of rungs connecting them. In this particular scenario sloth like aliens walk along the rungs and use voice and smell to command the vessel. The humanoid scouting crew is in effect standing on the ceiling. The vessel is undoubtedly alien, but not so alien that your users would get lost trying to work out that there were obviously functions carried out at certain stations, and that commands or information could somehow be passed into them. [Answer] ## Change fundamental reference frames. For instance, make them operate on a time-scale that is far from ours. There is a fundamental difference to how we think of objects like a sizzling firework, a flowing river or a moving glazier based on how fast we operate. We tend to turn phenomena operating the same speed as us as detailed and nuanced, while phenomena too fast or slow tend to be either generalized into simple blocks or ignored. Beings where years are like minutes will see whole other classes of phenomena as nuanced or simple. Think of a machine that is driven by continental drift - it would be very difficult for human explorers to even recognize it as a moving machinery, it might look like a static construction of unknown purpose ("Weird shape.. probably religious in nature"). [Answer] I would suggest hiding it behind the scenes as much as possible. That way you can get something that 'feels different' but whilst being able to to handwave away a lot of the "why". This is taking the 'sufficiently advanced seems like magic' line. However for the sake of explanation - imagine nanotech and AI and neural links are core components of what they do: * Things get changed invisibly by nanites. * AI gives really incredible prediction and precision. * Neural links give 'invisible' comms and general situational awareness, as well as the ability to *use* nanite/AI without anyone knowing - or being able to 'steal' and make use of themselves. So an alien might walk into a firefight, and casually walk in such a way as the bullets just don't hit, because it knows precisely where and when they're going to land - they're dodging, but doing so enough in advance that they're merely altering gait slightly. And then people fall over - unconscious or dead - because an appropriate blood vessel or neural pathway has been 'blocked' by nanotech (ordered by neural link, driven by AI). Similar principles apply to vehicles etc. - we have vehicles because the static overhead of production. But with rapid (nanite) replication, it becomes entirely plausible to make a house - or car, or spacecraft - a temporary and personalised 'structure'. [Answer] *Alien* (as in technology) is really a subjective thing. What one person finds alien, other might find Earthly, with a higher technological level. If you wrapped yourself up in a reflective suit and held a smartphone, you could easily pass as an alien to people only a century ago. For me, alien technology would be something that appears to defy the basic principles of science as we know them. Making a seedling transform into a tree within minutes would be perfectly alien to me. Being able to listen voices 1000 km away (without using transmitter-receiver method) is alien technology for me. Warping time and space is alien. It's not the show that makes it alien, it's the substance. [Answer] If you want a simple suggestion, imagine this technology as if it were invented to be wore/triggered/used by a cat/snake/frog/octopus or other animals. They live in our world, but have developed different sizes, sharper senses, weird appendages. Then adjust as you see fit. [Answer] You can introduce elements that just don't work for humans, either that they lack the strength of senses to pick up on it or there is some physical restriction. Another fun way to twist it is to go the opposite. Think of something that is Human tech that the aliens would not be able to use or have difficulty using. If you want an exercise in how to make something useful but alien try doing a series of tasks with your non-dominant hand and then describe the feeling. Sure, you can, but it feels off. That sort of feeling is what you want to inject into your new alien teck [Answer] There is also a chance, that they are not accustomed to our environment, and therefore are not meant to be here. For example: A Plant raised in a container, with no flow of air, will break by the slightest wind around it. So why not make them or their technology be effected by our environment? For example a spaceship, that moves with the wind (as a tree does)? And, if you (your species) comes from outer space and have never had, or had heard about (our) athmosphere, you wouldn't know about this strange behaviour (aerodynamics mentioned in the comment below), would you? And maby they don't need aerodynamics (if they never had an athmosphere, they couldn't have accounted for this (and never build an aircraft that like ours, that uses this "feature of nature) and therefore invented a different kind of engine (maby magnetically) or something like this. [Answer] Have them communicate by vomiting, and licking each others vomit up, thus exchanging complex organic molecules which encode long chains of data. Or some disgustingly messy other fluid exchanges [Answer] The best way to show that something is alien is showing how humans react to it. The human characters will not understand it. They might be afraid of it. They might be repulsed by it. They might accidentally break it. They might accidentally operate it, with disastrous consequences. They might overlook it. It might not be easy, finding the door on an alien wall. This can be contrasted with aliens using their own technology. They have no problems at all. [Answer] Make every gadget, machinery, computational device "organic" simbiotic living thing according to their "biology" and almost seamlessly integrated to them. For example: They use atachable / detachable "cell phones" that integrate their (let's assume they have ears) auditory nerve and vocal nerves or deeper integration corresponding functional brain regions. * can repair and "upgrade" (evolve) themselves * they are immortal * can breed sexualy or asexualy (self-cloning) * can use many energy sources including hosts native biological energy source * can change their shape and texture (like chameleon) PS: In TV sci-fi series "Far Scape" has a living space ship called [Moya](http://farscape.wikia.com/wiki/Moya). At some point Maya gave birth to another space ship called [Talyn](http://farscape.wikia.com/wiki/Talyn) [Answer] Humans are "Carbon based organisms". So anything that is also carbon based is likely to look like something we're used to seeing. Squid, trees, lizards etc. So don't make your aliens carbon based! Scientists have long theorised about "Silicon based organisms" as a viable alternative. It is very likely that we simply wouldn't recognise such a being as a living thing until it did something like move around or radiate some exotic energy (RF / x-rays maybe). They might even be entirely solid objects without moving extremities and move around using magnetic fields attuned to the local fields of the planet they live on. They might drink [Fluoroantimonic acid](https://en.wikipedia.org/wiki/Fluoroantimonic_acid) for refreshment (no sane human would drink something 10 quadrillion times stronger than 100% sulphuric right?). They might be entirely powered by the photoelectric effect (they basically become temporarily dead at night, comeing alive again at sunrise). Silicon has been explored before in SF literature, so why not choose another element and try to imagine a world where that element became more successful than carbon as a basis for life? [Answer] * Green or red characters on a screen * Pointy things coming out * Looks like a cockroach * Slime * Has a low hum * Interiors are poorly lit * Scientists will not be able to activate it, but the main character will do it accidentally * Mist (whatever color the screen characters were) [Answer] A couple of ideas that is not still said: make your aliens communicate over radio waves. This will allow them to talk without making noise and they will be able to use their equipment without any external input or output. This may also help them to pick up our radio or TV broadcast. Make them sightless, instead they could use their radio waves similar to radars. With different wavelengths and refraction patterns they could make out different properties of matter. But that would not be the color. For instance, their static text could be made out of variance in material properties such as density. That kind of text would look like a decoration of different materials to us. They could also be sensitive to our visible light, and live under lower frequency light. Thus their vehicles will have windows, but they would be opaque to us. ]

[Question] [ In many science fictions we see planets which are designated by a particular terrain type. For example, Dagobah is a swamp planet, Tatooine is a desert planet, and Kamino is an ocean world. However, Earth has a much more varied and interesting geography with all kinds of environments stretching from oceans to desert and everything in between. How realistic is it to portray a planet as a "Jungle Planet"? Is this simply a storytelling technique to help viewers/readers identify the location from its distinctive appearance? [Answer] Planets which have something that we might consider to all be a single climate given the way we classify things based on earth is entirely plausible, for certain climates at least. Mars easily qualifies as a desert over its entire surface. There is climate variation, but all of it is something we would call "desert". Similarly, you could have more water to the point it covers everything and the entire planet would be ocean (which isn't exactly a climate in and of itself). But oceans can have varying climates. Variations based on depth, insolation, currents, etc. The intertropical convergence zone would likely be a massive band band of thunderstorms. Then you'd have calm doldrums, and then utterly mid latitudes where massive hurricanes sweep across periodically. A global swamp or jungle though doesn't seem workable. A global wetland would need an almost perfectly smooth planet where everything was in an absolutely perfect balance. "Jungle" is fairly specific and tied to the specific nature of life on the planet. Both global jungle and global wetland have the severe problem of where you maintain a reservoir of water to generate the rain with oceans. Making a single climate planet habitable is also problematic. Without phytoplankton and forests, a desert planet isn't going to have an oxygen rich atmosphere, unless you do something strange like the Sand Worms of Arrakis in *Dune* which produce ridiculous amounts of oxygen. Then again they are generally just ridiculous creatures so you might as well just declare that where the oxygen comes from is irrelevant to the story. One might say that Arrakis isn't functionally a desert for its native life because lack of water is irrelevant to them. What makes a place a "functional desert" is extreme scarcity of a resource life needs, but which can be gathered, retained, and re-used. Most likely a solvent or other medium within which biological chemistry occurs. It's improbably that life would originate on a planet which is entirely functionally desert for that life. [Answer] I'm going to take one of your examples here: the **desert planet.** Is *that* realistic and plausible? **It turns out that it is realistic.** [Wikipedia describes a desert](https://en.wikipedia.org/wiki/Desert) thusly: > > A desert is a barren area of land where little precipitation occurs and consequently living conditions are hostile for plant and animal life. The lack of vegetation exposes the unprotected surface of the ground to the processes of denudation. > > ... > > Deserts are formed by weathering processes as large variations in temperature between day and night put strains on the rocks which consequently break in pieces. > > > [Desert climate](https://en.wikipedia.org/wiki/Desert_climate) is described as: > > Desert climate (in the Köppen climate classification BWh and BWk, sometimes also BWn), also known as an arid climate, is a climate that does not meet the criteria to be classified as a polar climate, and in which precipitation is too low to sustain any vegetation at all, or at most a very scanty shrub. > > > [Polar climate](https://en.wikipedia.org/wiki/Polar_climate) is defined primarily by the lack of warm summers: > > Every month in a polar climate has an average temperature of less than 10 °C (50 °F). > > > It turns out that [the above description of desert climate sounds like a pretty decent description of Mars' climate](https://en.wikipedia.org/wiki/Mars_%28planet%29#Climate). Mars' large orbital difference between perihelion and aphelion creates constant thermal stress, which the thin atmosphere does little to reduce; temperature swings of nearly 200 Kelvin are seen between the extremes on the surface and between summer and winter, whereas summer daytime temperatures of around [35°C have been measured](https://en.wikipedia.org/wiki/Mars_%28planet%29#Climate). Mars also shows a fairly large difference between daytime and nighttime temperatures, which is a property typical of desert areas, but I cannot seem to find any specific figures at the moment. [Answer] I think you're indirectly asking about scope. Any world deals with levels of encapsulation. The lower down the levels the bigger the frequency. As with anything the higher the frequency of something the more time it takes to develop it so therefore the more likely a person is to create quick methods of applying detail to it. ## **Lucas vs. Tolkien** The model for each franchise is identical, the scope is not. Lucas' top-level encapsulation is a universe, Tolkien chose a planet. Lucas' universe has many planets, Tolkien's planet has many regions. Lucas' universe has swamp planets, Tolkien's planet has swamp regions. It all comes down to how many examples of a specific level of encapsulation you have. If you're doing a universe like Lucas, you most likely don't have the time to describe all of your planets to the same level of detail as Tolkien did with Arda. [Answer] A desert planet is not unrealistic at all - plenty of them exist. A desert planet able to support life would presumably be possible, if given the right kind of atmosphere. A completely-ocean planet would not be too implausible either: it would be just like earth, but with much deeper oceans. An entirely-jungle planet, however, may be difficult, as it would need to have a roughly-consistent temperature. With a bit of modifications, there could be fast-growing plants that can survive in any climate (especially if the planet's axis is not tilted so that the amount of sunlight each plant gets is constant). You could certainly have a planet completely covered in plants, but it seems unrealistic for all the plants to be tropical (which may be part of the definition of a jungle). [Answer] I think it is totally plausible for there to be planets with a single kind of terrain. For this to happen, the whole surface of the planet must be at roughly the same temperature (unless you're talking about a desert planet and allow different types of desert). This doesn't happen on Earth: the poles are much colder than the equator. The situation is even worse on Mars, in terms of the temperature differential between the poles and equator. On Venus the entire surface is indeed at about the same temperature. This is because Venus' thick atmosphere and strong winds are so efficient at redistributing heat across the planet's entire surface that any temperature differences are smoothed out. Like Venus, I think a planet with habitable conditions could have a relatively uniform surface temperature. With a thick enough atmosphere the surface temperature would be relatively homogeneous (in detail, this also depends on things like the atmospheric composition and spin rate). I don't see why you couldn't have a planet like Dagobah, with a thick atmosphere that maintains jungle-like temperatures across the whole planet. Or a water world that is a global ocean with similar temperatures. Since a thick atmosphere often has a significant greenhouse effect, a planet with a uniform surface temperature would likely be relatively far from its star, in the outer parts of the habitable zone. In the most extreme case you could imagine a free-floating planet with no star. It's plausible that such planets could have life, either under a thick hydrogen atmosphere or in an ocean under a thick layer of ice (see here: <https://aeon.co/essays/could-we-make-our-home-on-a-rogue-planet-without-a-sun> or here: <https://planetplanet.net/2015/06/04/real-life-sci-fi-world-8-the-free-floating-earth/>) [Answer] "Jungle Planet" is, as it happens, particularly difficult. A desert planet just doesn't have much water (though life-bearing might be difficult), and ice world is consistently cold, and a water world doesn't have geological forces that push more of its earth to above the waters. A jungle planet would not only have to be consistently warm -- possible with a thick atmosphere and plenty of global warming -- it would need to be wet. This would mean large bodies of water, thus pushing it toward water world. I note that while it may fall under a single description, any inhabitants will see distinctions. A water world will have colder and warmer, winds and doldrums, life-rich regions and places without marine life. ]

[Question] [ **Setup:** The year is 2018. Malicious virus escaped secret lab and managed to kill 99% of all humans between January and April 2016. Not-so-average Joe spent his last two years of basic survival with the rest of people who are immune to the virus. Joe managed to gather about 500 survivors and they live off the ground in a small village. Although situation is still rough, the group managed to get the basics going: They have running water, good shelter, protection from winter and enough food to keep them healthy. Now the idea arises in Joe's head: About 20 miles away, there is abandoned nuclear power plant. And because it did not explode in last two years, Joe assumes the internal security systems of such nuclear power plant managed to shut off the core automatically. Because there is no electricity in the grid, Joe also assumes, that getting into the plant is just matter of time (And he has all the time on Earth) The group consensus is: Better die because we screwed something in the plant than to die simply because we will die anyway. And having some electricity in the grid would be huge bonus for Joe. **Can Joe start up the nuclear power plant?** Some background: * Joe can use computers and understand basics of most common operating systems (Windows - Linux - Mac OS, where he knows only real basics of Mac OS) * The plant really managed to shut the core off * But the plant is also powered by solar panels, so some internal security systems may be working * The virus in question managed to kill 99% of people in three months and the country where Joe lives was infected first. (so everyone killed within a month) * Joe knows only the basics how power plants work. Nothing else. * The power plant in question is "Made in USA". Although not really in function anywhere, just assume the power plant is [Westinghouse AP1000 model](https://en.wikipedia.org/wiki/AP1000) * Joe is not stupid, so the village in question is positioned in a way that if something wrong happens in the plant, the village itself stays intact * And as stated in the question: There is no electricity and no internet. If Joe should study something, it should be printed out and accessible in local library. [Answer] Not the answer to the black start (that has been already answered), but given the > > But the plant is also powered by solar panels, so some internal security systems may be working > > > premise, Joe the Average would do much better if he decided to rip away the solar panels (and attached batteries) and install them in the village. A community of 500 does not need much electrical power (it's not like each family must have a freezer and a washing machine). Jury rigging solar panels is much easier than restarting a nuclear plant (and keep a piece of the grid operating!). If you have half an electrician with a multi-meter among the survivors, you are done. You can even go scavenging for solar panels in the vicinity. But yes, the best long term solution (in 20 years, much of the solar panels will degrade into uselessness) is hydro power. Maybe wind generators, but those are much less reliable. [Answer] I spent 6 years working as an engineer at a Nuclear Power Plant. It would be impossible for myself to start up a plant, even assuming it was shut down cleanly, the spent fuel pool was somehow not a pile of radioactive slag, and all the consumables for maintaining the site were available. We had a staff of hundreds to handle all the day to day maintenance issues such as oil for motors, grease for bearings, and all sorts of things I can't remember. However, assuming that Joe was able to solve all the issues listed above (Finding enough power to kick-start the power plant, finding something to consume all the power, etc.) and actually got the plant generating electricity, he (and his 500 co-survivors) would be unable to keep the plant running for very long. Some critical piece of equipment would eventually fail and require repairs which would require some specialty manufactured piece of equipment that would be unavailable. Joe's best choice would be finding some power source that is designed for long-term unattended use such as solar panels and batteries/inverter. However, Joe should be able to find a wonderful collection of tools and equipment at the Nuclear plant that would be quite useful (including electric powered vehicles that he could charge from the solar plant) for things not related to the power plant itself. [Answer] **Not so likely** Besides Joe not knowing the first thing about electricity let alone nuclear power the main issue here is to [black start](https://en.wikipedia.org/wiki/Black_start) a high power plant without significant available electricity to start with. So, as Wikipedia tells us, "a black start is the process of restoring an electric power station or a part of an electric grid to operation without relying on the external transmission network." We can safely assume that the grid is down given the apocalypse and such. The AP1000 is listed with approx. 1.1 GW of electrical power. Wikipedia again suggest "require station service power of up to 10% of their capacity for boiler feedwater pumps, boiler forced-draft combustion air blowers, and for fuel preparation." (okay, not all of those apply to a nuclear power plant). Reduce this a little due to the AP1000's advanced design with "35% fewer pumps" still leaves you with about 50 MW necessary for start-up. With no off-site power supply to speak with. 50 MW of solar power, as mentioned in the question, is really, really huge. You need to be quite lucky to find something like that nearby and it's also unlikely that the plant would have such a large standby capacity (e.g. diesels) on site. Best shot to make it work (again besides having Joe learn quite a bit about electricity and which buttons to press at a the nuclear power plants control room) would be to start up a hydroelectric power station. Giving that a second thought - finding and operating one of those should give 500 people plenty of electricity to be fine with. [Answer] In addition to the other very valid concerns raised in other answers, the other massive problem here is what to do with all of that 1.21GW of power. Assuming you don't have a DeLorean sitting around that can sponge up the leftovers, and also assuming that the electrical grid is trashed because of, you know, the apocalypse and all, then there is the much broader problem of *load balancing* the electrical grid. This is a huge subject, beyond the scope of this answer, but the magic of the electrical grid requires more than just a working power plant. A nuclear power plant can't just be turned on and running without a sufficient load to power - the energy it produces has to **go somewhere**. With only 500 people you will be producing WAY too much power - much, much more than can be consumed by your post-apocalyptic population. Before even thinking about starting up the power plant you will need to figure out what you are going to do with the leftover power. Assuming the plant will be running for the next decade or so, you will need a long-term solution for dumping all of the excess electricity somewhere sustainably - particularly in a way that is adaptive to the load being drawn by the population. Normal plants do not have this sort of infrastructure. Nuclear is a base-load technology so the balancing on the grid is taken up by smaller generators like gas turbines, etc, which power up and down to match consumption on the grid (ie: we never usually have to DUMP power, we always have to *supplement*). Alternatively, if the grid is actually still intact then you might have the opposite problem - one single plant may still be connected to an entire continental electrical grid and trying to turn it on will result in the one single plant trying to push power through to every single electrical appliance across the entire grid that is still connected and turned on. A load mismatch of this sort would generally result in your plant's generators overheating and possibly burning out or melting. In either case, Joe would need to figure out how much of the grid was still intact, take appropriate measures to isolate a portion of the grid that the plant intends to power (driving around and manually actuating substation disconnects, clipping cables, whatever), calculating the effective load on his newly created mini-grid, accounting for a means to precisely dispose of unused power... even for a single electrical engineer specialized in power systems this would be an enormous task. Average Joe doesn't have a hope in hell. TLDR; Trying to turn the thing on is putting the cart before the horse. If average Joe thinks this is step-1 in the process then he absolutely will not succeed. There would be a lot of infrastructure work necessary to prepare before you could even think about the "turning it on" step. Average Joe with a team of 500 average people would probably need at absolute minimum several years of planning, intense study, luck, and determination to even remotely have a chance of possibly pulling this (pre-planning and preparation step) off. [Answer] There is a fundamental mistake in the question. A nuclear powerplant CANNOT be without power for very long without a catastrophic incident. The reactor vat itself will be shut down safely, but that's not the issue here. the REAL issue is the radioactive fuel handling pools. These are pools of water containing the depleted radioactive fuel that are remnants of the fuel rods. The radioactive waste will continue to generate heat and require cooling for years. This happens in pools that constantly need to be filled with water by pumps. without electricity or diesel generators to power these pumps, these pools will drain in days. Once they are drained, the waste will rapidly heat up, ignite and burn the entire plant. It will be Chernobyl all over again. Large areas will be contaminated by particles that will take hundreds of thousands of years to decay. The biggest problem is that this won't JUST happen in the nuclear power plant you're interested in. This happens in EVERY nuclear power plant in the entire world. and there are over 400 of those. Depending on where you are, your small settlement can be at serious risk. <https://www.youtube.com/watch?v=91JZCbGLCvk> is a video from a documentary on life after people that explains what happens. [Answer] Very unlikely. First, how can Joe know that the nuclear power plant is OK just because it didn't explode? Engineers learned a lot from the Chernobyl disaster. Modern nuclear power plants [are designed](https://en.wikipedia.org/wiki/Passive_nuclear_safety) to safely contain the reactor core in case of an accident even without any human interaction (Fukushima Daiichi was unfortunately even older than the Chernobyl plant and had similar design issues). So even in case of a complete reactor meltdown, the facility might look perfectly fine from the outside. He might not notice until he breaks a door open and is greeted by several Sievert of deadly radiation. But let's assume that the facility actually is safe. I am not a nuclear technician, but I am quite sure that starting a nuclear power plant requires more than just pressing the "On" button. However, chances are good that Joe will find the manual in a cabinet in the control room and can use it to teach himself the procedure to start the reactor. But the problem is that the reactor likely did not shut down properly. When the apocalypse happened, then the reactor likely shut down automatically because some safety system was triggered. That means the facility is now in a failure state. Trying to get the facility out of that state might require some manual intervention. Trying to do this without the advise of a trained technician will likely cause more damage than good and might ruin the power plant once and for all. Even with a technician the facility will require offsite power to start up. Nuclear power plants also require offsite power to keep running. Loss of offsite power is a critical failure event which will cause an immediate shutdown. After the powerplant was started it might be possible to rig it to ignore a LOOP condition, but again, this will require a trained technician who knows what he is doing. And then it comes to maintenance of the plant. Sooner or later Joe will have to get some new fuel elements (if he is lucky, there might be some in stock) and replace the old ones. I am quite sure Joe will certainly not be willing to get anywhere near these, unless he is willing to sacrifice his life for the community. Actually, unused UOX elements are safer to handle than one would assume. They are toxic, but only lightly radioactive (but Joe might not be aware of that). The used ones, tough, not so much. [Answer] This anecdote may be slightly off the original topic, but it illustrates how hard it is to get a power plant up and running from a "cold" plant (black plant in the examples above). When I was in the US Navy on a destroyer, we were running BECCE drills (Basic Engineering Casualty Control Exercises), which were designed to simulate battle damage and train us how to respond to keep our ship either in the fight, or at least afloat. The exercise we were training on was losing our after fire and engine rooms (holes), which meant we had to cross connect the forward fire & engine rooms to allow us to get steam back to the after engine room so it could turn the screw (propeller) and generate electricity. The captain dropped a live grenade off of the starboard bridge wing to simulate a torpedo hit in the forward fire room. We were supposed to do simulated casualty control for flooding, except we never got the chance. The grenade went off directly beside the forward fire room's main fuel feed pump, knocking it offline, in moments we lost fires in the forward fire room (and the after fire room was already "cold" for the BECCE drill), so steam pressure dropped quickly. Since both engine rooms were cross connected to the forward fire room, we quickly expended all our steam, and both the drive gears and the ship's turbine generators all went off line, the whole ship went dark, which automatically caused the emergency diesels to start up, but it's minutes before they've settle down and can provide consistent electricity, and then only to emergency circuits (fire pumps, fuel feed pumps, forced air draft blowers, ventilators in the holes, etc.). Once you lose steam in a fire room, you have literally minutes of sufficient heat to do a "hot start", otherwise you end up having to do a cold start. A true cold start takes 72 hours on this type of ship. Well, with no fuel pump (it was mechanically driven), and no electricity to run the auxiliary for several minutes, as well as the forced air draft, they quickly ran out of time. The emergency generators kicked in almost immediately (I know because my station was at the forward emergency generator, and it started automatically, scaring the crap out of us because that wasn't part of the drill, and we weren't expecting it). Imagine being inside a tight metal box with a giant diesel generator inside it... We had an entire ship ***full*** of trained engineers, who knew our plants inside and out, and we took hours and hours to get the plant restarted. We knew what had happened, and what needed to be fixed, but still we were dead in the water for most of an afternoon and into the evening before we got steam back up so we could get underway. We even had other ships of the same class in close proximity so we could get parts or assistance if needed. Imagine what Joe has to learn, figure out, configure, appropriate, fix, just to be able to think about starting the plant. Our plant was a fairly simple #2 diesel fired steam boilers, basically, if you have enough electricity to run the auxiliary fuel pump, forced draft blower, and ventilation, you can start it with a butane lighter and some knowhow. I've gone through naval reactors training in the USN, it took us six months of intensive training to get to the point where we knew enough to actually be taught on a real reactor (another six months). It's quite unlikely that Joe's ever going to get his plant running. [Answer] I concur that the answer is a massive no chance, but that the plant (or really any heavy industrial plant) would be a gold mine in all sorts of other ways (Assuming you can avoid a radioactive liquid metal fire). Consider, these things are built on rivers often as not, to provide the cooling water for the condensers, and they are full of all sorts of pumps and valves (Also, tools, cranes, all sorts of stuff). For 500 people, forget the nuclear bit (absent keeping the cooling ponds from drying out, river water would not be ideal, but needs must, dig a trench), a centrifugal pump looks a lot like a hydroelectric turbine if you squint just right, and you probably have a river. Start small, find a modest low pressure centrifugal pump of a few KW or so rating (The admin buildings heating system might be a good place to look), build a weir to get yourself some head, run the pump backwards as a turbine and flash one of the motor phases with a car battery to produce some residual magnetism in the rotor. Capacitors to provide the reactive power for the magnetising current should be an easy scrounge. If you want to scale up (a lot) the condenser feedwater pumps are MW class machines and VERY hydroelectric turbine like, but that will be years down the line (So close the sluices and drain them to preserve the things for when you do need them). You want to be thinking simplest way to skin the cat, the objective is power for 500 people, not a working nuclear reactor. Ok, so "average Joe" here is a mechanic who read a bit around electrical machines and maybe holds a ham license, but the point is to use the peripheral parts to build technology to solve the problem you have not the one you would like to have. Regards, Dan. [Answer] If the nuclear part is really important to your story and these are some really reckless survivors you may be able to have them combine hot radioactive waste with thermoelectric couplers to make electricity from heat. Basically this is what you could have them make <https://en.wikipedia.org/wiki/Radioisotope_thermoelectric_generator> [Answer] As another survivor of the US Naval nuclear power program, I'd like to add that ~2 years without maintenance, even assuming spent fuel storage was properly maintained, none of the pipes in the power plant proper would still have water in them. The primary coolant absolutely must be pure and chemically treated, especially in a pressurized water reactor of that type. My experience as a plumber/mechanic for submarines tells me there is no such thing as a pipe that doesn't leak, so two years of nobody looking after topping things up, will not only have empty pipes but dried sediment, probably with loverly, hard to find, hot spots of radioactive material. I don't know if civilian plants keep distillation rigs on site, but our shipboard ones were powered by steam, so you have a bit of a pure water problem as well. EDIT: This also assumes nobody has made off with any critical pieces of equipment in the interim. Additionally, one of those critical pieces, that is not very mobile, are the reduction gears. Those are what take the 10s of thousands of RPMs your steam turbine would operate at, and reduce it to something the generator can cope with. If they are not properly cleaned and oiled before attempting to start, there could be trouble. [Answer] Could you restart and run a nuclear power plant? If you're not a pro, you don`t even know yourself. So at best (worst) average Joe would believe that he can do it. And then he would most likely find out that he was wrong. --- edit to clarify: Check against yourself. Can you do it? yes/no? Compare your pplant skills to average joes skills. Are you better/worse/same? ``` yes/better -> he cannot do it yes/worse -> he can do it yes/same -> up to your story no/better -> he could never ever do it no/worse -> he might have a chance no/same -> he cannot do it ``` [Answer] No. If you hadn't ever learned it, could you even start a (not auto-gear) car? No. Could you even use a simple desktop computer? No. In this case, you would probably succeed if you searched for documentation, books and other use info. But in the case of a nuclear power plant, there is no such thing. It is a complex mechanism. You don't have any idea what you need to do. If you are a nuclear physicist, specializing in nuclear reactors, *but* without any knowledge of the actual control panel of the nuclear reactor type, maybe you have the same chance to succeed, but a very limited chance. Honestly, you couldn't even restart a Coca Cola producing production line. *You didn't find, where you can it power on.* It is not so simple that you only press a button and you get cola. It is actually many machines, each of them with its know-how, and these machines work in interaction. Do you remember as you sit before a computer first time in your life? Do you remember as you sit in a car first time in your life? Do you remember the complete chance-less feeling that you don't have even the slightest idea, what the hell is it? *A car, and a computer, both are designed for easy to use.* Even a cola production line isn't. And a power plant, totally not. --- In case of the nuclear power plants, there is a bonus mechanism to fight with. There are *very* hardcore safety system to prevent a core meltdown (explosion is impossible, but the society doesn't know this, and the core meltdown can have also a minimal risk for the people living around). These are redundant systems, extending eachother, and in case of practically any "problematic", they will shot the power down. They are also passive systems: if you don't deserve them, they will also shot. (For example: the boron controlling rods which are controlling the nuclear plants are controlled by electric motors. These electric motors must work *against* the weight of these rods. If they don't get power, the rods fall into the reactor core by their own weight, and the reactor stops. It is very important engineering feature: the "default behavior" of any part of the system must be that the power plant simply stops itself.) From such systems there are many (at least 3, redundant), and you can only avoid them if you know all of them deeply. That, you can't do. --- But, from the other side: such power plants must handle the case if their systems are powered off. If it is needed, they are often switched off from the power network or your country / continent, and in this case not only they can't give power to your country, but also they don't get. But it is very important, i.e. if there is no power, you can't start the control room, which could start the power plant. :-) For such cases, they have large diesel generators, which is capable to power the control system of the power plant for a long time. They have a lot of diesel oil, and well serviced. It is not solar panel, they are costly and work only in daylight. Diesel generator is used since the first electronically controlled power plants (which were probably coal power plants, probably in the U.S., probably around 1850-1880). If you have luck, you can find this oil in them. In your life, and maybe in the life of your children, it will be enough to heat your home. ]

[Question] [ In an environment in which acute radiation hazards are common what tools or techniques could be employed by primitive people to detect and thereby avoid radiation exposure? These people do not understand what radiation is, but they do understand that there are invisible forces that make them sick. I’m essentially looking for something analogous to a canary in a coal mine which can detect and warn of a dangerous yet invisible situation without a clear understanding of the nature of the danger. An example of this scenario would be a post apocalyptic situation in which primitives live near old melted down nuclear reactors. Another might be a world without a strong magnetic field where solar flares pose a radiation risk. [Answer] It happens that in 1986 I participated in the cleanup after the Chernobyl catastrophe. I worked as a radiation measurement specialist 20 m below that blasted 4th reactor. I worked at the station for the whole July. It was the worst time, for the radioactive dust levels increased till the finishing of the Sarcophagus. As we had only masks as protection (but they were really good... when we had them), I learned that **people can easily feel the radiation**. A radioactive dust particle, sitting on your skin, creates the same feeling which you all know from the sun burn. Only the feeling is concentrated in a point. So, people do not need extra methods to detect half of the problem - the radioactive dust. The negative side of that skin detection is that you don't feel the burn at once, when you feel it, you are already burnt. And when you feel one particle, probably you had got much more, but you don't feel them YET. Or they are inside you and you won't feel them at all. You must: 1. not allow them to get inside and 2. remove particles from the skin as early as it is possible. The solutions are: wear respirator mask everywhere except wet cleaned closed rooms, cover the skin everywhere, especially in connections between clothes' elements, showering after a walk, washing exposed parts skin even during the walk or work outside. And better don't go out when it is dry and the wind blows. And the time after rain is the least dangerous. And this way will really work - I worked in the very epicenter, and even didn't follow the rules fully (the needed services were extremely badly organized), but I do live and have healthy children. But I was there only 35 days on the station and 35 days in the town. And your people live there. But they will use not so dangerous territories for living. I think, it will well compensate the longer time. Notice, there are two kinds of radioactivity you should think about: gamma rays and beta+alpha rays. Gamma rays are much less destructing. But you cannot stop them by clothes. Alpha and beta are much more destructing, but they could be stopped even by air and easily - by clothes. As a result there are two sources of radioactivity. The radioactive dust - you are getting a particle on your skin or in your inside and it is killing you by all three kinds of rays, and the background radiation level from all surrounding, that consists of gamma rays only. If you had got only one radioactive dust particle inside, you don't need anything else. It will sit in you and kill your cells around. And sooner o later, some of your cells around it mutates - and the cancer comes. So, your task is not to allow a single radioactive particle to be on or in you for a long time. As for gamma-ray background radiation, in our reality the levels that can be felt by organisms are deadly for humans. Of course, your people can find some plant or animal that is very sensible to radiation. Young animal or sprouts are more sensitive. Only by inventing some animal/plant and using a very young form you could compensate our very bad radioactive sensitivity. (look page N.5 [here](http://www.iaea.org/inis/collection/NCLCollectionStore/_Public/29/036/29036491.pdf)) As for detection by radioluminescence, it also doesn't work until radiation level is already too high for humans. Only if a luminescent material was put directly to the eye, and the detection was done at night, then separate sparks while a particle passes through would be noticed. But if the source is an old reactor, then the main danger will be the dust. There will be another problem. Radiation does not change in a monotonic way - here it is OK, a kilometer further worse, further - even worse, and on that hill the worst... No. You have a clean place here, extremely dirty place around the corner, absolutely clean room nearly because windows were closed, terribly dirty door of this very room, and so on. The fact that you passed the area and remained clean doesn't mean you won't get very dirty the next time. It can happen if you take a slightly different path. Your protagonists should evaluate, mark and remember exact paths, not the areas. And they will need to recheck their paths often enough, for the wind is moving the dust. --- It is funny that such society should create a special etiquette. One of the most impolite things you can do there is to raise the dust. Smokers there could be only among some self-killing fanatics. Smoking worsen the output of dust particles from our lungs. But those people from the tale could invent some medicine to improve such output. They could wash their noses by salty water several times a day. --- After some time I got bad feeling about your people - where they will get the clean water? The food can be planted under glass roofs in clean rooms, but I can't think out the source of water for them. [Answer] Try to use [Radioluminescence](https://en.wikipedia.org/wiki/Radioluminescence) Radiation is quite difficult to detect in low-tech environment, and because humans are among the species most vulnerable to radiation, it will be challenging to find any other organism that would serve as an indicator. However, if primitive people can synthesize radioluminescent phosphor materials like zinc sulfide, they can have a reasonably sensitive detector. Zinc sulfide glows when bombarded by alpha, beta particles, or X-rays, and the effect is quite noticeable even at radiation levels that are not particularly hazardous. One caveat is that this kind of detector can not be observed in daylight. [Answer] **One could use the canary in a coal mine type approach.** Canaries get sick quick when there is bad air. If your canary stops singing you know to clear out fast. For radiation it would take longer. Your primitives would bring a cage with some small animal to the area and leave it for a few days. The cage has food and water adequate for the period. If the animals are suffering bloody diarrhea or are sloughing their eyes when the humans return, the area is bad. If the animals are doing fine, the humans will probably do fine as well. [Answer] **Local flora and fauna** One issue with radiation poisoning is that, as in most poisons, dosage is key. Also, with radiation poisoning, damage is accumulative. So any biological test ("canary") that you design may survive a few days, give you a false sense of security, and led you into a dangerous zone. Even if you realize in time and you do not die directly from radiation poisoning, the increased rate of cancer will take a heavy toll on your tribe. And of course, if you repeat this mistake often, it will end wiping your entire tribe. So the best method would be to check for local flora and fauna; as those have been around for a long time and so are a better indicator of current situation. When approaching a dangerous area you will notice: * Less plants and animals. * You see an inordinate amount of ill/mutated/dead without apparent cause of animals and plants. * You see more and more of the simpler species (insects, ferns, moss) and less of the more complex species (mammals, birds, trees). With enough time, it is possible that some variety of the most basic living forms evolves to be more resilient to radiation1. With time this species will likely colonize all of those zones that are hard for the regular species to live on, so just by spotting that specific kind of life form in considerable amount would warn your heroes. --- 1It is more probable than it happens to simple life forms because their simplicity means that changes/mutations "break" less of their organic chemistry, and also usually they have a higher reproductive rate. [Answer] Fertilized eggs. You place fertilized eggs about, and periodically (daily-ish) gather them back up and try to hatch them. My grandmother had a job doing just that at Berkeley in the 40s. [Answer] Except for the spots where the radiation is high enough to be lethal immediately-or-close-to, they probably won't figure it out. Humans, especially primitive humans, are shockingly bad at nailing own the causes of what makes us sick. the examples are countless. * Lead poisoning. From ancient roman pipes and to pewter cookware to leaded gas, we've been poisoning ourselves with lead for millennia, and seem to be completely surprised if and when we figure it out, and then go right back to using it. After the romans figured it out (hardly a primitive people) we didn't figure it out again for another 1600 years. * Scurvy. Figuring this out literally took millennia, and even when we did, that knowledge took centuries to really spread. Millions of sailors died to scurvy during the age of sail. * Most diseases. Malaria was killing people for 8,000 years before Romans started to suspect that maybe the bugs had something to do with it, and even so, we didn't really nail it down until the 20th century. Yellow fever, likewise. Cholera's association with water tainted with human waste, plague's association with rats and fleas, none of this was really understood by vastly more intelligent civilizations than the one's you're depicting. If they're being exposed to radiation-sickness causing levels of background radiation, then maybe, *maybe*, they'll incidentally tend, due to natural selection, to live and prefer the areas that are less radioactive, over the course of hundreds to thousands of years. Avoiding the immediate area around nuclear reactors, near any deposits of corium, would be considerably faster as a process, courtesy of @Valerio Pastore's answer. [Answer] Take two hairs, join them at one end and mount them on a metal nail fitted into a decent insulator (say amber or something similar), charge the arrangement with static, the hairs will move apart due to electrostatic repulsion. Add ionising radiation, the charge will bleed off and the hairs move together. It is a dead crude electometer, but would probably be good enough for very crude dosimetry (And indeed one version of the dosimeters used in the nuclear industry works on exactly this principle). [Answer] Unfortunately, none. This is not a quick assumption. It's been [researched](http://www.wipp.energy.gov/fctshts/warned.pdf) (see also on [Slate](http://www.slate.com/blogs/the_eye/2014/05/14/_99_percent_invisible_by_roman_mars_designing_warning_symbols_for_the_nation.html?via=gdpr-consent)) as part of the long-term storage of nuclear waste. One of the assumptions there was that the storage should be safe even in the case of a decline in civilization. It's probably one of the few areas in which physicists had to call in help from anthropologists, instead of the other way around! One of the key conclusions was that even with our help in preparation, there would be no way to have future non-industrial people detect radiation. First off, detecting radiation is not sufficient. C-14 is all around is, that's how carbon dating works. Potassium is also common enough, and naturally radioactive. But you're specifically concerned about elevated radiation, so you need a quantitative detector. Pre-industrial age, you cannot rely on electricity, yet it's the ionizing nature that makes radiation harmful. Other answers have suggested vegetation. We know from Chernobyl that's not a reliable indication. The vegetation there recovered well before areas were safe for humans. Plants are just a lot simpler than animals. A tree is much less likely to die from losing a branch than an animal from losing a limb. [Answer] The only available detectors would be...the people themselves. The amount of radiation coming from the exposed core of a nuclear plant will kill you almost instantly. The people unfortunate enough to wander inside that deadly wreck seeking shelter would never leave. They'd make the first ring of bodies. Anyone else coming near the plant for the same reason would see the remains of those who came first. Would probably suspect something wrong -after all, no one shows signs of being eaten by predators, and everyone old and young alike is dead as if struck by a plague. Newcomers walk away, but they have been exposed to a very hard dose of radiation. They will die not far from the wreck. New group passes by. This time they see the remains of the dead outside the monolith. They too think 'plague'. They don't touch the bodies but again they are close enough to get high doses of radiation. They will not die immediately but they'll start suffering radiation sickness soon. And so on, until at last there will be consolidated word that the monolith is a cursed place of death, that its waters are poisoned, no one must approach it ever EDIT: 300 seconds of exposure to the notorious Chernobyl's "Elephant's foot" will kill a healthy person in 2 days -considering that before one day has passed people are suffering severe radiation poisoning symptoms. Imagine instead these primitive persons, who know nothing about radiation, looking out for shelter and not only finding it in the monolith, but also discovering -how lucky!- a source of heat! What could be more alluring than a warm, godsent metal that gives up heat without fire? Imagine these hapless innocents starting to cuddle by the warm source, before getting headache, nausea, cramps, as the seconds pass and they still don't understand they have sentenced themselves to death...But they get weaker and weaker. 300 seconds pass and they cannot but writhe and curse their fate as their DNA is destroyed and their organs collapse... [Answer] The question is what sort of timescale do you need the canary to die to warn you that there's a problem? If you can settle with not immediate, then butterfly larva are very sensitive to radiation when fed contaminated leaves. <https://setac.onlinelibrary.wiley.com/doi/pdf/10.1002/ieam.1828> A colony could easily keep a collection of butterflies and then feed the larva samples taken from an area they plan to move to; If they see the butterflies are deformed, then they don't go back to that area; or actively move away from it. If you need "faster than you", then I'd probably opt for a slave or prisoner; or even "volunteer". Get them to be more exposed than you and depart when they start to look ill. Don't forget that history is littered with human sacrifice for much less meaningful reasons than "it might save the rest of the group". The more desperate the situation, the more likely I think this would be employed. If you need "more humane", then clearly it's not such a bad apocalyptic world where you're having to fight for your survival; and you can afford to use option 1. The lack of wildlife I suspect is a poor way to work out how bad an area is; since ignoring the sounds of birds, you're unlikely to come across many animals anyway; so working out the difference between "not many" and "slightly less than not many" is not going to be easy to do; and by the time you do notice it, it's probably too late. [Answer] If the previous civilization was sufficiently advanced there’s no reason to believe they wouldn’t have had tools to detect the radiation. I really like the zinc sulphide answer. Perhaps there are a few “talismans” or something the primitive people have that glow under radiation, but because the knowledge has been lost they don’t know how or why this happens. You could also have an underclass of people who explore the dangerous areas but are considered heroes for the risks they take. [Answer] With flowers. Not by seeing if there are more or less of them, but with the actual flower. Hairyflower Spiderwort (its a real plant and thats really it's name) can detect radiation. I'm sure there are others that can as well, I just happen to know this one because it's also edible and has a very memorable name. <https://flawildflowers.org/flower-friday-tradescantia/> [Answer] There are several chemical solutions that change in the presence of radiation. Making them isn't easy enough to be called primitive. Silver or Phosphorus compounds are the goto candidates, but both are fairly likely to be at least as dangerous in use as radiation. Slightly better might be to hope the humans are not the most radiation sensitive thing in the [environment](http://www.iaea.org/inis/collection/NCLCollectionStore/_Public/23/039/23039160.pdf) and flee when they see things die. Dogs are slightly less radiation tolerant than humans and very plausibly attached to primitive humans, but most small mammals and birds are hardier, and some insects and reptiles handle more than an order of magnitude more. Fortunately most trees and plants are noticeably effected by continuous doses required for humans to get radiation sickness over short times. So if the people are worried about slow problems like old waste sites they should have a good idea of where to avoid. Unfortunately plants don't wither fast enough to avoid human problems if exposed at the same time. [Answer] I was reading up about [gemstone irradiation](https://en.wikipedia.org/wiki/Gemstone_irradiation). This is a process in industry to change the optical properties of gem stones. It made me think a primitive people might become aware of a special kind of gemstone which is affected at far lower levels of radiation which would indicate danger. That could work like the talisman idea mentioned previously. The primitive people could fashion these gemstones into items which are used by shamans to worship an invisible god and protect them from evil or something like that. [Answer] It's worth highlighting that we didn't even know that radiation was a thing, let alone what kind of thing, until at least Henri Bacquerel in 1896, maybe Willhelm Roentgen a year before. It kills slowly, and is relatively everpresent, so if this is a true alternate-universe kind of thing and your people are "primitive" as in lacking history and technology, they have slim chances. A great example of this is more likely disease. Bear with me, it directly relates to your question. It isn't radiation specifically, but it's hardly any less magical. Where microorganisms go, Antonie van Leeuwenhoek reported their discovery no later than 1676. John Snow, an English doctor, determined that cholera (and likely other diseases) were spread by water in 1854. However, actual basic sanitation practices, like hospital workers washing their hands, weren't implemented until around 1873, famously at the behest of figures like Florence Nightingale. Before this, maternal mortality rates were at around 20%, maybe higher in some areas, because no one was practicing basic sanitation. Something you can point at with a microscope is a lot more obvious, but it took us over a hundred years to hammer into our heads that yes, this is real, yes, we can stop it, and yeah, we've been killing our patients by not doing so. You can imagine how much of a mind-boggler radiation is in comparison. Most people still don't understand it, and we're not even living in a primitive society. That said, basic sanitation systems such as sewage systems have been found in early Babylon. There's no documentation of why it worked, only that it clearly did. Minoa (Crete) and Herakopolis (Egypt) had flush toilets well into the BCs. What was evident was that something, somehow related to the filth, was a contributor to disease. It is highly doubtful that they had a sophisticated understanding of microorganisms and pathogenesis, but the linkage was clear. If your universe contains a lot of highly radioactive sites, I would suggest this. Perhaps a simple photographic plate, with a combination of silver nitrate and halide, could be kept in a dark box (like one made out of thin opaque metal). A scout could enter an area with it, and return, and if the plate was exposed in spite of a lack of light, alpha/beta/gamma radiation could be assumed. They would get other clues from the environment; such as a lack of life outright (get out of there fast!) or a hyper-prevalence of mutations. Their explanations for these things might be, well, wayward; maybe they think the area is cursed by the gods or something like that. Maybe the people who looked at the plates would be considered priests or something like it. However, the correlation is what counts. Radiation isn't hard to detect; it's explaining it to people that's difficult. [Answer] A cloud chamber is a primitive device that was used many decades ago to visualize tracks of radioactive particles. Construction of a cloud chamber can be accomplished by a student. See <https://blogs.scientificamerican.com/critical-opalescence/how-to-build-the-worlds-simplest-particle-detector/> Construction and use of a cloud chamber might be beyond the resources of a primitive society, but capable by a group of survivors. [Answer] The primitives could [use "ray cats" that glow in the presence of the radiation](https://vimeo.com/138843064) This was a [proposed solution](https://en.wikipedia.org/wiki/Human_Interference_Task_Force#Fran%C3%A7oise_Bastide_and_Paolo_Fabbri) by Françoise Bastide and Paolo Fabbri to the problem of making a symbol that would be able to mark the presence of radiation and be useful for 10,000 years. There's even a [catchy song](https://emperorx.bandcamp.com/album/10000-year-earworm-to-discourage-settlement-near-nuclear-waste-repositories) about "ray cats", and an episode of a well known [podcast](https://99percentinvisible.org/episode/ten-thousand-years/) that mention them too. Joking aside, this could be a valid way to detect radiation assuming that the primitive people lived in a country that actually genetically engineered "ray cats" or some other animal that changed appearance in order to warn of radiation. [Answer] A longer-term solution would be to use humans in the following way. Incorporate into culture that a boy needs to live alone in the woods for 5 days on a place, selected by the elders, to become a man. If they die or become extremely sick, apparently they are not worth in the eyes of the gods. [Answer] There is actually a pretty straightforward answer to this. You need only look to history. I can't guarantee you can detect *all* radioactive materials by hand, obviously rudimentary detection techniques will have rudimentary precision. One of the properties of Radium that greatly intrigued Marie Curie and other scientists of the 20th century was that Radium is always warmer than the surrounding temperature, no matter what environment it is. It gives off heat, seemingly from nothing. The more radioactive the material, the stronger this property is. It is well known that Plutonium-238 glows from it's own self-heating. [](https://i.stack.imgur.com/EQEa0.jpg) By Department of Energy - <http://www.doedigitalarchive.doe.gov/ImageDetailView.cfm?ImageID=2006407&page=search&pageid=thumb>, Public Domain, <https://commons.wikimedia.org/w/index.php?curid=1034533> So the raw heat of the radioactive material, and glowing in extreme cases, can be used to detect more strongly radioactive material. Asking to detectvery much less radioactive material without precise instruments might not be so simple with direct immediate effects. [Answer] People forget sometimes that this is a fictional website. I think that the answer that there is no "adequate timely indicator" is true, but an alien life form in a risky "radiationally variable" may have evolved special detection techniques that would let people know that high radiation is coming. [Answer] ## Taboo and superstition Based on past experience of ill effects sometimes appearing on people who live/go in particular places, you'd expect superstition to take over. "We just don't go there". It's taboo. That's it - no detection, but avoiding certain places just because; reinforced by ill health actually happening to people who had violated the taboo. Once formed and ingrained in culture, such taboo concepts can be very long-lasting. [Answer] I believe that star trek next generation did this one. Data was stranded on a planet and lost his memory. He had in his possession a case containing metal fragments from a crashed satellite. The fragments were making the towns people sick and no one knew why. He didn't know who he was, or remember any of his scientific knowledge but he still knew how to reason. He discovered that a sheet coated with phosphorous would glow in the presence of the metal. He concluded that something must be coming out of the metal that caused the phosphorous to glow. <https://en.wikipedia.org/wiki/Thine_Own_Self> [Answer] There is a form of radiation that primitive people can most certainly detect. It's visible light. Our eyeballs are tuned to detect and process radiation in the frequency range from red to violet. We use the resulting information to help us live and thrive. So perhaps the primitive people in this world of yours have an extra sense organ, one that detects ionizing radiation. If the resulting sensation is unpleasant, as pain is unpleasant, such an organ would have survival value. How would such an organ work? I have no idea. How would it come into existence? It could be intelligent design. Or it could be simply random mutation coupled with natural selection. This last mechanism takes a long time. How much time do you have? [Answer] ## Suggestion Use their eyes. ## Explanation Other answers have mentioned how [humans can detect electromagnetic radiation directly using their eyes](https://worldbuilding.stackexchange.com/a/116389/26872). I would build upon that answer by mentioning that various animals have different rods/cones that allow them to perceive different parts of the spectrum, like further into the blue/UV portion so it would not be a stretch to include the concept of people with special 'vision' who can see the radiation. I know that is not a technological answer but it does solve the issue of being available to even the most primitive of societies. In addition I would point out that astronauts have problems sleeping due to '[light flashes](https://en.wikipedia.org/wiki/Cosmic_ray_visual_phenomena)' they could see even with their eyes closed and are suspected to be caused by cosmic rays or Cherenkov radiation. This can be taken advantage of simply by having people report said light if they attempt to sleep in an affected area. They wouldn't have to understand radiation to attribute the experience to 'ghosts' and begin to shun the location. ]

[Question] [ > > In a capitalist Society, you work, you earn money and you buy a shovel to dig a hole > > > In a communist Society, you are given a shovel and told to work > > > [Alt History Hub](https://www.youtube.com/user/AlternateHistoryHub) Communism was a major rival of capitalism, both being on opposite side of the scale. We often say how the best, most stable economic option is capitalism, but when we look at media it tells another story. As a wild example of what I mean, look at apocalypse survivor groups in movies; In almost every story, the "good" group uses a communist system(the group provides for you and you work for it) but bad groups use a capitalist system(ration cards). This is just an example but it did get me wondering, *can* Communism be stable? Is it possible that a communist nation can remain stable under the basic idea of communism? If so, how can they do it? [Answer] # Tl;dr Go with openend’s suggestion of handing the economy over to an optimizing AI (Iain Banks’ Culture?) # Long Answer This really comes down to what you consider “Communism.” The People’s Republic of China calls itself a Communist country, and over the past few decades, it has been (mostly) extremely stable and has had the fastest economic growth in the world. Since you’re asking whether this is possible in theory, I take it you would invert the excuses G.K. Chesterton made for Christianity and Marxists made for the Soviet Union: Communism hasn’t succeeded; it’s never been tried. And because Denmark is generally considered the model of a socialist country, many people with strong opinions on economics can prove from first principles that Denmark does not exist. If Real True Communists have to agree with everything Marx said about history and economics, then they’re in trouble, because a lot of it is definitely wrong. At best, they’ll end up appropriating some Marxist vocabulary to dress up a more modern world-view, for example, emphasizing the adjective in **useful** labor until they’ve justified working with a *de facto* utility theory of value, and adding so many special cases to Marx's inevitable stages of history that the outcome is no longer predictable in advance, only inevitable. ## The Information Problem Cort Ammon points out that no system run by humans is ever truly stable, which is correct but not very constructive. sdrawkcabdear presents the classic three arguments against Communism, which is a useful starting-point from which to ask, *How communist can you be before one of those problems becomes fatal?* The first is the kind of information transmitted through market prices. China and Denmark both let the market set prices on almost everything. The problem for Communism here is that a market will only find an optimal price if there are a lot of competing buyers and sellers, not a monopolist. (Of course, this is equally a problem for anarcho-capitalists so doctrinaire that they don’t allow the state to regulate monopolies.) But a lot of industries are natural monopolies: they have increasing returns to scale, or network effects. Even classical economics tells us that a perfect market is not perfect: it fails to handle cases where a deal between two people benefits or harms a third person who isn’t part of the deal and whose interests aren’t factored into the price (*externalities*), or cases where it’s impossible or inefficient to make everyone pay for the services they use (*public goods*). The most realistic “Communist” proposal to deal with this problem was to write an AI that would monitor how much of everything the country had and optimize its resource allocation. This ran into two problems: there wasn’t enough computing power in the Soviet Union in the Fifties to make it remotely feasible, and the algorithm kept telling the central planners that efficient economic allocation looked a lot like market prices (it even computed a vector called “shadow prices”). But we could revisit that with modern computer networks. Amazon, DeviantArt, eBay, StubHub or Google might well collect enough local information to determine how much demand there is for products in the niches they dominate. Openend worries about backends in the software; one might also ask how we can prove the pure motives of Jeff Bezos, Mark Zuckerberg and Warren Buffett. There’s a lot of computer science research into writing provably-correct, secure code, and a lot of people would be motivated to vet the source for bugs. We would need, however, to decide what “correct” would mean. Already, everybody argues that what they do is so valuable to society that the government should subsidize it, including for example libertarians who want the government to abolish taxes on income from investments and pay for defense and law enforcement by raising taxes on income from labor. Arguments today about public subsidies and the tax code would become arguments about the utility value of health care for the poor and what sort of positive or negative externality we should deem marijuana or carbon dioxide or traditional local culture to have. This would raise the same issues of public-choice theory that “Capitalist” countries face today. Maybe a hodgepodge of taxes and subsidies and regulations and public options would end up running with less overhead, less duplication and more returns to scale under central management. Maybe competition comes from different publicly-owned firms. ## The Incentive Problem If Communism can’t reward people for working harder, Stalin’s Soviet Union was not really Communist. There’s no inherent reason an economic system where the government owns all the means of production couldn’t pay workers on commission or give them performance bonuses. If nobody can have private property or a higher standard of living at all, then the system has to try to motivate people through praise, threats, awards, power, fancy titles, special privileges and other non-pecuniary means. So a successful Communist country might not depend entirely on those; it might give people a universal basic income and then make them work for luxuries. That’s basically what modern capitalism does too. In a post-scarcity economy or one where automation has basically destroyed the value of most people’s labor, the government might not care how hard most people work. Their labor isn’t necessary or important in a world of robots; if their revealed preference is to live on charity and spend their spare time blogging or playing chess or reading and criticizing literature or something else that we today consider a hobby, maybe the goal of an enlightened society should be to give them the personal freedom to make that choice. Traditional aristocrats would have agreed! If a day job they could fill produces almost no value and they would hate it, but there’s more than enough wealth to buy everyone happiness and personal autonomy, a society could choose to do that. Even Ayn Rand thought that a system like that would be *too* popular: she personally believed it was wrong, but she agreed that most people would like it and vote for it. Conversely, if society decides everybody needs to have some job, any job, just so we don’t spend all our lives in a holodeck, you’re looking at the utopia of *Star Trek: TNG*. The purpose of that kind of Communist government is to provide everyone not just their material needs, but a sense of purpose. ## Power This is basically the same problem any form of government has, but under a modern liberal democracy, power is broadly distributed. Employers have a lot of power, but so does government and so do unions and so do retired voters. If a single hierarchy controls everything, how do we keep it accountable? The answer is going to involve combining Communism with democracy, but it’s not as if getting democratically-elected leaders to act in the best interests of the people is a solved problem either. If we’re solving economic efficiency by having an algorithm optimize production and devising an incentive structure, maybe that program is open-source and patches are approved by democratically-elected maintainers. Maybe the right to free speech also means the right not to be fired for saying something your boss happens not to like. Maybe all managers wear microphones and body cams like the police to guarantee they can’t abuse their power to sexually harass the people they supervise. [Answer] You need perfect information, uncorruptable leaders, and an enforcement mechanism. Why does communism sort of work at a small scale (small groups < 15) but hit tons of problems at large scale? There are 3 issues. First is **information**: In a centralized economy the government has to choose production for the country, where capitalism just lets market forces do that. So the leaders of a centralized economy have to predict how many iPhones, slices of bread, and sheets of paper the people of the country will need and thus how many to build. This is harder because the millions of people in a country may not even know themselves. Also, when the government guesses wrong there is no back up, no other company who made extra food or phones that don't explode. This means when the central economy goes wrong, it goes [very wrong](https://en.wikipedia.org/wiki/Great_Leap_Forward) (communist countries have a bad habit of starving their people). The Second is **motivation**: How do I get you (a worker) to do what the government wants? I can ask you nicely, but what if you are not a really nice person? In a capitalist society I could offer you a carrot (reward) to do it or a stick (punishment / remove reward) if you don't. In a communist society we are all equal so I can't give you a carrot, and I shouldn't really give you a stick unless you did some thing wrong. So how can a communist government motivate people without using capitalist methods? The third is **power**: The central government has massive power in a major country. Who holds them accountable? Communism assumes that everyone is out for the common good and doesn't really try to deal with that fact that their leaders may be greedy / less than completely altruistic. The system needs some way to keep their leaders in check. [Answer] No system with humans is ever truly stable. They just have different instabilities to deal with. If you think about it, the stable state for humans is "dead." To remain alive, we need a constant influx of energy (which we typically get from the sun, through one channel or another). In mathematics, there is a term which is useful here: metastable. A metastable point is a point which is not stable (perturbations will cause it to eventually degrade towards a stable point), but it is curiously long lasting. A classic example is when you perfectly balance something like a broomstick. While the stick is vertical, the system is certainly not stable (the stick is going to fall unless the human intervenes). However, right around the vertical point, the moment which pulls the stick to the left or right is so faint that the stick can remain upright for long periods of time. The key to this is typically to have a controlling force which is trying to maintain this delicate equilibrium. In the case of balancing a broomstick on your hand, you move your hand back and forth to try to keep the stick upright. In the case of governments, that controlling force is the actions of the high government, trying to keep the system coherent in equilibrium. In communism, the failing case occurs when people stop working for the common good and start working for themselves. However, if you can maintain enough control of the system, you can bring those individuals back into the fold. In capitalism, the failing case occurs when a group of people start working together to a common benefit. This sounds like a "desired" state, but it's also the start of a monopoly. Pure capitalism has little to no defenses against this. Of course, being humans, we don't work in such blacks and whites. We work in muddled greys. Our "capitalist" society has anti-trust laws and voting franchise and all sorts of decidedly non-capitalist tools to keep capitalism in check. Likewise, the famously communist countries have generally had to pick up *some* degree of capitalist behaviors to survive. For example, you can only price fix for so long before you have to permit the prices to move in the direction the market wants. What you end up with is something more complicated. You end up with something that looks stable in some ways and metastable in others. You end up with something which can withstand some types of perturbations without moving, and falls to others. There's a famous artist in Colorado who goes by the name [Gravity Glue](http://gravityglue.com/). He puts together rocks in unusual structures that seem to defy gravity. He's open about his technique: his structures are just barely stable, because each rock is resting on a tripod of points. These structures are stable against small perturbations, but eventually topple to large ones (such as high winds). Still, you have to appreciate the energy he puts into making us wonder: [](https://i.stack.imgur.com/eJAgq.jpg) [Answer] The fundamental reason the Socialism (and Communism is just a subset of Socialism) can never work is the "[Local Knowledge Problem](http://www.econlib.org/library/Essays/hykKnw1.html)". This problem was outlined by F.A. Hayek, and explains why *any* command system economy is outperformed by the free market. In the simplest terms, knowledge is localized and particular. As an actor with agency in a free market, you have the ability to observe these bits of information and act on them immediately, reaping a benefit for yourself and associates who you choose to share with. Imagine you are about to go outside in the pre internet age. You stop at the door and take a look at the sky and feel the breeze on your skin, and decide to get a sweater. In a command economy, information needs to be gathered, sent up a hierarchical chain to be processed and then orders sent back down the chain to be executed. The "Ministry of Outerwear" takes your information about the weather, collates it with a multitude of other observations, processes it (perhaps getting an average of all the reports), and late in the afternoon you are advised to get a winter jacket. This also assumes there is no errors in the reporting, and no stoppages in the chain of reporting and orders. There also needs to be a feedback mechanism to tell the "Ministry of outerwear" if the orders were correct, and of course some sort of incentive for the various people in the chain to actually be quick and accurate in their work. Compounding the problem is the fact that an economy is a complex adaptive system with thousands to millions of nodes (read "[I pencil](http://www.econlib.org/library/Essays/rdPncl1.html)"), and inputs are not reflected in linear outputs. Indeed, outputs may be spatially and temporally distant from inputs, and indeed just because input "a" created output "x" last time does not guarantee that the same inputs will create the same outputs next time. So even in theory, there is no way that Socialism or a command can compete successfully with a free market. And if theory isn't enough, there are enough real world examples of Socialist economies running into the ground to make the point as well. [Answer] **To answer this question, let's take a look at two cases where Communism is common, and works very well**: 1. Families and Extended Families Did anyone live in a family where the person who cooked received a wage in return for their labor? Which children are paying for their parents to raise them? In side most families, most resources are communal. In this case, communism says nothing about the power structure in the family; it merely describes how resources are distributed. Market economics don't work in a family, because the disabled, the elderly, and the very young don't work and don't contribute resources. In a purely capitalistic family, the babies would need money to pay for breast milk. Note that while families can be considered communist, that resources are not perfectly shared, and needs for all members are met differently, and that the power structure embedded in relationships is not at all democratic. For example, when my son cries for a snickers bar at the grocery store, there is a power dynamic in our negotiations that is entirety UN-democratic. Notice that it is not a dictatorship either, but just a human relationship. 2. Tribes and Clans I have never lived as a member of a tribe or clan, but it is my understanding that many tribes and clans exist, and have existed in the past, operated with economies that were not based on money. [Graeber spent a lot of time in his book](https://en.wikipedia.org/wiki/Debt:_The_First_5000_Years#The_concept_of_.22everyday_communism.22) describing how societies work without money. Without going into to much detail, communism "works" for tribal economies when all members of a community are interested in allocating resources based on need, and when all members of a community contribute resources based on ability. **Answering the question** In the two cases above, communism works when resources are distributed based on need as decided by the community. Communism thus would work only when all members of a community are interested in allocating resources based on need, and when all members of a community contribute resources based on ability. Despite the plethora of negative responses above, it is entirely possible that such a society could exist. I have heard many people say "ever been to Sweden?" when asked if communism was possible. I've never lived in Sweden, but everyone I've met from there complains a lot about how horrible the social system is in the USA. Then they say something like "at least the taxes are low." Is it possible that Sweden's economic plans could be adopted everywhere, and everyone would live like a Scandinavian? Honestly, I don't see why this is impossible. However, this is world building, and "Global Sweden" isn't interesting or funny, or at all related to Sci-Fi. **My World Building Answer: A Stack Exchange Hive Mind** Through technology, cybernetic implants allow everyone additional processing power, and 24 hour access to stack exchange, Facebook, and youtube. As all questions are answered and all problems resolved, individuality is subsumed buy the collective, personal desires for resources diminish as the collective strives for ideal resource allocation. Then, communism. [Answer] Your description of "communism" looks to me like a definition of a command economy, and has little to do with "communism" as Marx defined it. So I'll use command economy instead. Modern corporations are a wonderful example of command economies. The workers typically don't buy their equipment, the equipment is given to them. They are told what to do by their managers, and sometimes have input in how to solve them; but they can almost always be overridden. The workers have the freedom to quit, and in some legal systems to organize and strike. In rare cases, the workers are part of a trade organization (like Engineers) and legally cannot be ordered to do certain things (like sign off on safety) by their managers. They don't bid for work, pay for their own tools, etc. There are ridiculously huge corporations out there that are larger than many nations. Obviously this command-style economy isn't limited to small groups. These command economies are embedded within a pseudo-capitalistic framework. The goal of these command economies is to realise "economic profit" (profit above the "fair" rate of return on assets), which usually involves creating or aquiring monopoly pricing power of some kind. The capitalistic background requires that these command economies compete between themselves as they seek to reach such a state. Once they are in such a state, the pressure eases off, and benefits for those in charge of the command economy (the executive officers) increase. Those outside their ideal state of owning a monopoly strive to gain the power to get there, or bumble along at lower profit levels trying to locally optimize their costs and income. I would argue it is that churn -- the ability for the corporations to *fail*, plus the ability for workers to swich employers -- that helps prevent ossificiation and inefficiency; but that is a second order effect that only *kills* the corporations that become "sick", not how (most) healthy corporations *work*. The end game of the corporations in Capitalism is to swallow the market and ossify. You can see many, many corporations trying to do this, and a lot of effort is put into preventing monopolistic capitalism from warping modern economies. Capitalism isn't stable as it has an inefficient attractor state. Command economies aren't stable as they also have inefficient attractor states. Humans optimize around problems, and a fixed economy that doesn't give you absolutely everything is a kind of problem. For an economy to remain stable against the attacks of optimizing humans, you need to have humans working to prevent the inefficient attractor states where the economy is captured for private benefit (either via owning everything, or telling everyone what to do for your benefit) without themselves falling into those traps. The solution isn't a static system generating stability, but dynamic stability and constant viligance. Naturally over medium terms (centuries) no economy is "stable". So the question becomes, how do you create a stable enough command economy? One solution is to constrain it by a sufficiently powerful outside force which is secure enough to not require undermining rivals within the economy. That is roughly how corporate command economies avoid going off the rails, where the outside force is the government (legal system) and rivals (who can poach workers, among other things). Another temporary stable method would be resource constraints, where members universally see their common survival rests on unity and helping the group. This is only marginally stable, as in one direction they die, and in the other the commander can start hoarding resources/power and convert to a more typical dictatorship as the danger passes. [Answer] Well, that's a topic which keeps me awake at night. Basically the problem is described in sdrawkcabdear's answer. The only solution I came up with: **Have some years or decades of AI research, then give all executive power to a central AI.** This AI (if programmed right) is Uncorruptable within limits. It allows for equality among humans and to contain those, who always seek to accumulate power. The AI would gather more data than google and its algorithms enable it to control the economy/law enforcement and so on based on all current data and based on all digitalized data collected through human history. In Practice: All citizens (and this needs to be enforced) carry a personal 'data pad' (sometimes called smartphone) and receive direct orders (if necessary) from the Central AI. This is the only possbility to contain the human urge for superiority (within in some individuals) These are the major problems of this concept: * Security: How can you make sure nobody installs a backdoor while the AI is created? Without this backdoor, how do you make sure, that the AI behaves as intended? How can the explotation of some weakness (as all information systems tend to have) later while the AI is in power, be avoided? How can the security of the central compound be enforced? * Technical Problems / Memory Corruption Digital Media ages. How can you guarantee Memory integrety for centuries? * Updates / Flexibility There are other countries with human leaders. The earth changes. How can you guarantee that the AI is able to cope with everything in a sensible manner? * Cultural / Acceptance Most People wouldn't like been controlled by a 'mindless' machine. Smarter people than me will be able to think of many more difficulties for this concept, but I think it's the only semi-realistic way of a stable, peaceful and working communistic goverment. [Answer] The question is basically flawed because the author equates capitalism with ration cards. The idea of capitalism is that resources are allocated through a bidding process—that those with capital can purchase and allocate the scarce resources of society through the mechanism of the free market. Thus, nothing is rationed. People simply do not buy things that are too expensive. Accordingly, every resource is devoted to its best and highest use, measured by the amount of money a resource is worth on the open market. Communism cannot work because the administrators are unable to rationally allocate resources. They cannot know the best and highest use of any resource, and they have no method to make the determination. The greater the number of decisions to be made, the more inaccurate decisions are made and the worse the situation is. [Answer] Communism as described by Karl Marx can never be a viable, stable economic system, for one very simple reason. In order to succeed, it requires people to set aside their greed and destructive levels of self-interest in favor of building up their community, and yet at the same time it explicitly villifies and seeks to suppress the one part of human nature that has the capability to reliably impel people to do exactly that: the religious impulse. [Answer] Stable communism may require a [post-scarcity economy](https://en.wikipedia.org/wiki/Post-scarcity_economy). When goods are scarce in a free market, prices rise. When goods are scarce in a regulated market, waiting times increase. You either pay in money, or in time: * In London, free-market rents are in the order of thousands of pounds per month for a small apartment. Rent-controlled council housing is cheaper, but waiting times are well over a decade. * Privately owned parking spaces may be very expensive in city centres. But in the same city centres, there is no fee to drive into town: the result is congestion (traffic jams); you pay in time. * In the former Soviet Union, there were long waiting times for goods such as cars. If prices were left uncontrolled, the price would simply have increased due to demand outstripping supply. There are many more examples, and the above analysis does not address the supply-side, but let's get to the question. Suppose we have a society where the quantity we can produce is *neither* limited by the availability of labour, *nor* by the availability of resources, *nor* by negative externalities. Self-replicating, solar-powered robots produce everything we need using resources mined off the asteroids, which contain enough of everything we need for a very, *very* long time to go. There's plenty of living space in Low Earth Orbit, and logistics have been solved as well. There remain attractive spots on Earth that will always be scarce. I would argue that if goods are not scarce at all, the distinction between a free-market economy and a regulated economy becomes less important. The underlying causes that led to the failure of the Soviet Union will no longer be relevant; there is no waiting time for goods in a post-scarcity economy. Nor would prices increase in the free market. If they aren't scarce, their price is very low and they are accessible to all. Which means the two are almost the same. Both communism *and* capitalism become more stable in a post-scarcity economy. [Answer] Several answers mention that communism works in small groups, like families, but fails in large groups, like countries. The main difference between these two cases is simply size. In a small group everybody knows everybody. If somebody becomes too greedy, people will notice and punish them. If you are a part of a society and everybody there thinks you have been bad, that *hurts*. Note that this system doesn't work perfectly, people can get blamed for things that are not their fault. In a large group people can be greedy and get away with it. And when other people see that, they will be greedy too, until greed becomes the norm. Communism is based on the idea that people will are not greedy, so communist countries break down. Capitalism is based on the idea that Greed is Good. This has its own problems, but that is not relevant to the question. The usual conclusion is that communism doesn't work, but I think that is too pessimistic. What is needed is a way for everybody to know everybody. What if there was a way for people to tell each other about unseemly greed? What if, before you talked to me, you could check me up in some database to see what other people think about me? There are many websites and apps today for sharing experiences with hotels and other service providers exactly so that you can check them up before you go there. What if we made the same system for people? If this worked, people would become nice simply because they want other people to think about them as nice. Unfortunately, these kind of systems can be gamed. "If you rate me high, I'll rate you high." I don't know a way around that and it could be a fatal flaw. [Answer] Firstly you are mistaken about something. Capitalism works well in a modern human society, but it is not supposed to work in every situation. What you have described for the apocalypse case, whether it is considered a form of communism or not, is too far from something that is supposed to compete with capitalism. It works more like the ancient tribes. When they could get a more stable environment, more space and more people, politics would become more important and the more efficient system, likely being feudalism or fascism, would appear. They could provide you resources and you work for it, too. Capitalism and the idea of communism could possibly compete and come back only much later. The "real" communism, while I don't know what the exact definition should be, is at least supposed to be after capitalism. I have posted some pro-communism comments many years ago on the Internet, and now I feel stupid about that. So I have changed the original "communism" bit by bit, and is finally creating something that seemed feasible, but is it still communism? For most people who don't care about communism, probably not. For the people who have studied something about communism, it could be worse: everyone may disagree from each other. The fact is, the world will change rapidly that after a few decades, it's likely neither the modern capitalism, or the original communism would work well. Everyone tries to fix their ideas in their own way. And someone will come up with something that works. Is it capitalism or communism? It all depends on who come up with the new system and what they believes. A few ideas from capitalism or communism won't guarantee their failure. So in a way it can be stable. But the so-called "communism" we know is at best incomplete and old. Then in your definition: > > In a capitalist Society, you work, you earn money and you buy a shovel to dig a hole > > In a communist Society, you are given a shovel and told to work > > > The fact is, even in a capitalism society, most people are practically given a shovel and told to work. And I guess some communists also describe capitalism in that way. Most likely, This is what the person who came up with this definition really meant: > > In a capitalist Society, you can choose in some situations, that either you work, you earn money and you buy a shovel to dig a hole, or you are given a shovel and told to work. In some cases you can also do both together. > > In a communist Society, you are absolutely not allowed to choose the first option, no matter what. > > > That's unfair. If communism really worked better and there is enough resources like the modern world, the restriction is at best annoying, and there is no need to explicitly disallow the other way. I think this says everything. I mean, if you want to distribute resource in supposedly better ways in a capitalism society, you can. You could hire them and make a contract. You could provide them the resources for free if you have ways to generate income from them. What you cannot do is to disallow them from also buying and wasting some resources from elsewhere, which is not really that significant if it's not in an emergency. The "bad" way you have described is likely either the desperate case where everyone cannot make a good agreement, or someone is too impractical that they want to stick to some principle. But the other way isn't really disallowed by capitalism. And the restriction in the supposed communism would be a disadvantage at least in your case. Alternatively, someone may think like this: > > In a capitalist Society, someone earn money and they buy a shovel to dig a hole. They also give you a shovel and tell you to work. > > In a communist Society, someone capable give you a shovel and tell you to work. > > > It doesn't make much sense. Who is the capable person, after all? If they are government officials, then clearly no in a modern world. If that means "anything but market", then maybe, but it doesn't say anything about what this society could be like. [Answer] ## First, Some Definitions OK, first of all, you are mixing words. So I am going to clear that up first, then answer your question. You are saying something like "in capitalistic society ...." and then "in communist society". First of all, you are comparing apples and oranges. Starting at the basics, there is two dimensions to describe modern societies: 1. Economic dimension 2. Political dimension The economic dimension has a scale that starts at capitalism and ends at **socialism.** The political dimension starts at democracy and ends at dictatorship. Of course there are possibilities in between the ends of the scales. So Capitalism is in the economic dimension. Communism, is a mixture of two dimensions, it involves **dictatorship** (political dimension) and **socialism** (economic dimension). So you cannot compare it with just capitalism. Moreover, the *original* meaning of communism is a utopia, a theory in a book, a myth. What you seem to be referring to is the former *Soviet* system. That was a socialistic dictatorship. Though, you might know and talk about it as communism, because the US had a propaganda against the Soviet system, where they started to call it communism. But truly, it is not correct to call it that. Moreover, the real communism, that was described in the book of Marx and Engels, has never been truly used in any society (Stalin had a crazy idea, read the book and misinterpreted it, and said, "I want this now." Scientists tried to explain to him that communism is a utopia. He was stubborn). ## Theory of Communism The original theory of communism involves a huge innovation in manufacturing and robotics etc. Here is just a little bit of the theory so you understand: It says basically, that in the far far future, we will have such technological advantages, that we will be able to manufacture any product and create any service with almost zero cost. In that society, men will only work for pleasure, in a field that interests them. Every kind of lousy job will be done by robots. And since costs are zero, money has no meaning. People can just wish for anything and it will be theirs. Since there is no money, people are equal financially. And they live in a *community.* That's where it got the name from. ## Back to the Question But enough of the theory, let's answer your question. I guess you are asking me if **socialistic dictatorship** can be stable economic strategy. **The answer is yes,** as long as it has satisfying amount of resources and it does not have to compete with a capitalistic (either democratic or dictatorship) type of society for consumers. A socialistic dictatorship in that case would be stable, much longer then any kind of capitalistic systems. You see, there are two variations: Capitalistic dictatorship (e.g., People's Republic of China), or capitalistic democracy (e.g., The United States). But the quality of the products and services of this socialistic dictatorship would be very low. So, as soon as it would have to compete for consumers (with low quality), or as soon as it would have to import resources (and pay real prices for them) this system would collapse; that is the real reason for the USSR to have collapsed. The theoretical communism on the other hand would be a really stable system for a very long time since it would create equilibrium. But it's interesting to note that a really stable system that could be achieved nowadays would be a **socialistic democracy.** That has never been achieved nor tried ever. That would require the people to agree on dividing all produced goods and services equally among everybody in the society regardless of who created how much actual value. ## Background Information Unfortunately I am telling you this as I was raised in the Soviet system, then I lived through the systemic change and now I live in the US. I also have a masters in economics (the original name of the university was Marx), comparing modern systems so unfortunately I am telling you this from first hand. I am going to add one more thing that might be interesting to your question of system stability. to have a stable society, you also need political/legal stability. It is interesting to know that theoretically, you cannot have full democracy and capitalism at the same time. Capitalism will always diminish the poor's right to legal equivalence. Simply, in the US, a rich person can buy better quality of legal help in a civil lawsuit. This is true unfortunately in criminal lawsuits too, though in a limited way. So this basically diminishes some parts of democracy. Theoretically, a socialistic democracy would be much better for the masses (who would be poor and have only limited democracy in a capitalistic democracy), so a socialistic democracy would be the real form of democracy. Unfortunately, that will not likely happen, since everybody, rich and poor would have to agree on the equal allocation of wealth and legal rights. --- **Edit:** Additional thoughts Continuing this thought, I would like to emphasize the importance of political/legal stability in any system. Doubtless, the Soviet system was physically threatening, and intimidating, every second of the day—I lived in it with constant fear so I know. That was a brutal, primitive system, that really mostly physically intimidated you. But it was stable, since people were scared. Uprisings were impossible, and basic democratic right were diminished. The political "elite" were physically terrorizing the masses. But they provided a minimal secured financial living. Now I live in the US, a capitalistic democracy, and I see that it is a much more sophisticated system. But it has an "elite," the top 1%, who is financially abusing the masses. And it creates separation of the wealthy into certain zip codes, the rotting away of poorer communities, with ever higher crime rates, etc. That also creates political instability. So I believe that for long stability, you need some level of financial equilibrium too. A capitalistic democracy very much lacks such equilibrium. So, to your question, the final answer is that a **socialistic democracy** would be the most stable. [Answer] My two cents: The only real way to have communism work, on a large scale, is to have humanity evolve past wanting things, being greedy, and the desire to have a better existence than the next guy. Other than that, I really do not see a way for communism to work on the large scale. [Answer] Other respondents have pointed out that communism works reasonably well in families and clans, but breaks down in larger societies. The reason for this is that in larger societies, delegation becomes necessary for any governing to get done. In a family or a clan, the decision-making class consists of those adults who have achieved a certain status in the group. Having proven themselves, their opinions are at least given a fair hearing, and their grievances are not so casually dismissed, and they will know *why* each course of action was chosen. There may still be a single authority whose decisions are final (Dad or the Chief), but if such people are wise they exercise their authority only when consensus cannot be reached. The concentration of power is limited, because the number of people who have proven themselves will be a more-or-less fixed portion of the society. The young people will not always be satisfied with the decisions that are made, but they have the assurance that when they have proven themselves (in whatever way is required), they will be in the group that makes the decisions. If the elders have any wisdom at all, they will be preparing the younger people for the day that they will be in charge. The motivation for the young generation to forcibly overthrow the older generation is greatly reduced under such a system; why fight your parents and their friends for something that you can acquire by peaceable means with no opposition? Furthermore, the decision-makers have a great interest in being careful in their decisions, because the consequences of mistakes will fall upon themselves, their families, and their friends; and when the harvest isn't as good as it needs to be, everyone is more readily able to accept the privations that are necessary, because they see their friends and loved ones suffering just as badly. And since everybody knows everybody, the level of trust that is necessary to keep communism going is much easier to maintain. This all changes when the society grows beyond a certain point. When there are so many people that it becomes impossible for everybody to know everybody, the decision-making generation becomes too large for rule by consensus, and in order to get anything done at all, a degree of delegation is necessary. This has several effects: First, the number of decision-makers no longer scales with the size of the community. More power is vested in the hands of fewer people. Second, the amount of information necessary to make the correct decision has grown. You can know the needs of a hundred or so people. You cannot know the needs of a thousand people or a million. This leads to more mistakes. Third, as the concentration of power increases, the sort of people who want that power for the wrong reasons increases, and soon you have people in charge whose only skills are political rather than managerial. This leads not only to more mistakes (i.e., when 1,000 tractors are needed, the Ministry of Tractors produces either 100 tractors or 10,000 of them) but corruption as well (instead of producing tractors, the Ministry produces limousines for party brass). Fourth, there's less negative feedback for bad decisions. The consequences of bad decisions can be pushed off onto strangers. Fifth, and most fatally to the system, trust becomes difficult if not impossible. You don't have access to the harvest data, nor were you at the meeting where the potato ration was calculated, and you simply don't know most people, so you have only the commissar's word that the potato harvest really was bad this year, or that everyone's potato ration is really being cut by the same amount as yours, or that any variances from the standard ration are based on genuine need. It takes only one rumor of a feast at the commissar's house to shatter your faith in the system. So your real challenge in keeping communism stable is the challenge of maintaining the people's faith in the system. To this end, you either have to ensure that the decision-makers continue to act in good faith, or that the people remain willing to believe the propaganda in the face of mounting evidence to the contrary. [Answer] Yes, of course. There are a zillion successful communes all over America! California, Colorado and Washington unsurprisingly have quite a few. People point to the USSR and call it a failure of Communism when it was largely a caused by mismanagement and corruption - twin demons which can easily spell doom for a capitalist, or really anything-ist state if allowed to go too far or too long. [Answer] To implement communism, I think you'd need to solve the following problems: * *Tackle the Scarcity of Resources:* Some people may work voluntarily (see the case with free software when maintained by hobbyists) and others may not. You need a way to make sure that the goods and services provided by those who voluntarily work are enough to cover the needs of everyone. This problem will probably need to be tackled at multiple points, for example: + *Increase the Volunteers:* Educate people about why their contribution is important. You could even incorporate peer pressure and even potential social stigma for people who are capable of contributing but don't do so. + *Automate:* No job that can be performed by a machine should be performed by a human. Humans should spend their time only on those jobs that machines can't do or can't do well enough yet. + *Eliminate Unnecessary Jobs:* Eliminate all jobs that are still around for no reason other than because the people doing them would be unemployed otherwise. * *Embrace Non-Scalability:* Even democracy scales badly with population size, simply because every individual becomes less and less important as the governed population increases. Right now, millions of people can essentially lose control of the country they live in, when governed by a federation. It's not hard to imagine a distant future where the entire population of a planet suffers the same situation. Communism scales *even worse than that* and you need to embrace that. + *Create Small Self-Governed Communities:* It's tremendously important for people to feel like they are masters of themselves and that they are not governed by an external force. To achieve that, it's critical that the people in a community know *most* everyone who will be affected by their decisions. No more than two or three degrees of separation for any two people in the same community. + *Abolish Hierarchies:* Any hierarchical system (whether there is a unified hierarchy or smaller, specialized hierarchies) is vulnerable to an attack where the "root" of the hierarchy can be bought/bribed to work for a specific third-party. Instead, you can (for example) delegate all decisions to the citizens so that you can make political participation easy, accessible, frequent and meaningful. * *Replace the Market:* By most definitions of communism, the economy doesn't involve a market. However, the market in capitalism is there for a reason: to compute production based on demand. If you abolish the market, you need to replace it with something else. What? + *Use Technology:* In pre-technological societies, there is no computational tool comparable to the market. In technological societies of our level (a worldwide network of interconnected terminals at very high speeds), it's trivial to have a registry system in which people can use terminals (like their phones) to state their needs and a central program that can receive them. + *Stay Ahead of the Curve:* Do you have big data about the expressed needs of your society? You can now apply even the simplest pattern recognition techniques to allow the registry system to anticipate most demand patterns and start adjusting the production plan, even before a trend becomes conclusively visible. [Answer] The real problem with most implementations of communism is that in order to have all things in common or have a society where its individuals work according to their abilities and receive according the their needs is that you either need a group of people motivated enough by an ideal to preform this or you need a centralized power to make everybody do this. Giving somebody the kind of power it takes to make people give everything up and receive "less" back is scary stuff. Finding a group of people that can do it based on an ideal for a long period of time is also very difficult. However I would like to say that it is possible and has been done before. [Answer] The simple answer with Communism is to just look at what it is... and that can be described simply as "from each according to their ability to each according to their needs". Now let's assume 95% of people are "equivalent" so need the same things, but there are obviously some people that need more... Who are these people? Those who don't have ability to do things, such as the handicapped. We can give them more resources or eliminate them. I don't know whether communism makes a decree or argument, but every communist regime and some of the greatest philosophers in history says we should elminate them, so if you have any sort of physical disability, good bye. This creates a low level oppression, and anger, but everyone is suppressed by everyone else so it's just an unhappy unrest. This alone does not make the system "unstable" in that it's not unstable enough to be considered unstable with just this. The other issue is you have those who are deciding what people need. And this is the issue. I say who needs what and I say those who decide what people need need more and because all the people who decide what people need get this benefit they don't say anything. But what about the people who enforce the law... Well they need more, because if they don't get more they'll destroy the rulers, so they get more. Eventually you have a ruling class and an enforcer class that is so obvious that the populace sees it and sees that it is unfair. Now you have this hatred brewing under the surface and a ruling class that realizes this and sees that resources will eventually start dwindling which means even if they want to correct they can't. And this creates a highly unstable situation. What about if resources never dwindle? Humans have a natural fairness barometer and so as soon as it becomes obvious what's happening it creates an unstable state. Can this be avoided? Nope. There is always a corruption point or a point where humans will avoid it as unfair. [Answer] People forget communism has worked without turning into a dictatorship - on a small scale like the anarcho-communist [town](https://www.theguardian.com/world/2013/oct/20/marinaleda-spanish-communist-village-utopia) of Marinaleda which has been in Spain since [1979](https://www.nytimes.com/2009/05/26/world/europe/26spain.html?_r=1&pagewanted=all) and has a population of over two thousand six hundred people. It tends to fail when you have to try to implement it in one go over a much larger area. However, it is possible for you to try not to do that. Similar to [Ancient](https://en.wikipedia.org/wiki/Polis) [Greece](https://www.britannica.com/place/ancient-Greece), you could have a bunch of different communist city-states that work together as a type of 'superpower' similar to that. Basically, have a bunch of different commune-like cities and towns that tend to be somewhat independent of each other, but come together for greater trade or when they have to deal with a common threat. You can also use technology to help with dealing with creating resources (like how we are working on autonomous [farming](https://news.mit.edu/2023/titanic-robots-farming-more-sustainable-0309) bots right now) and having city-states communicate with each other to make collective decisions. [Answer] Communism invariably gets taken out by that one guy, the jerk. Here is how it goes down. Like minded individuals want to embark on this great experiment and go somewhere where they won't be messed with. All are given rations according to a finely balanced set of caloric tables and the required work from each person. Everything goes well until Bob gets assigned to dig the latrines after just completing the well. He's hungry, he wants more food, but according to the tables, he shouldn't get any more food. It won't take long before he filches a little bit extra. After all, he deserves it. The shortage is noted, others complain and discontent deepens. Maybe Bob is found out, who knows? It is this discontent that produces the wobbles in the system that makes it inherently unstable, especially when you try to scale up. The desire to succeed, to prosper, to build for our offspring, is not just human nature. It is instilled by 4 billion years of evolution. It takes effort and training to suppress that instinct beyond the family and we are more or less capable of it to varying degrees. It's that variability that makes communism wobble and fail. Communism absolutely requires that people are uniformly willing to sacrifice everything to the community as a whole. One person gets a little selfish and you end up with corruption, theft, bribery and so on. Capitalism is also far from perfect, but it copes with this variability by being highly variable itself. There are acceptable ways to go get "more" if you want it, without violating laws or harming others. For those who desire less, they are not required to push beyond what ever amount of work is necessary to sustain their less intensive lives. Sure, guardrail regulations are needed for the ones who are totally out of control. That's part of why it's been said of capitalism and democracy: They are the worst, but they are the only systems that work. [Answer] A basic definition of the communism as we learned from inside a communist-led state is that everyone works as much as he want/can and gets whatever he needs/wants. There was more, but not exactly interesting now. Some (partial! and partially stable) form of communism we see today in a societies where most of the "gross product" comes from a source independent of the labour efforts of the communist society members (be it oil, slavery or prolonged credit expansion). Everyone produces exactly as much as he wants (i.e. nothing) and gets... whatever some central distribution system assumes he needs. The communism is partial in a sense that doesn't work for everyone involved and is stable as long as money flow in the right direction, but it can take generations in order to collapse. [Answer] Assuming that by communist economy you mean a state controlled economy like the one the USSR had and not eurosocialist economies like Sweden you have to take care of demand, following the hierarchy of needs. The USSR did that, partially, and by the end of Stalin's rule starvation was a thing of the past. But when it came to go beyond food to consumer goods like cars, computers, the USSR wasn't able to provide. Why? Ineficient economy coupled with the cold war expanses. You need to increase the efficiency of the economy by applying to the whole society the methods that corporations apply: measure, optimize, fire when needed, hire when needed. The dictatorship of the proletariat require advanced managerial techniques developed by the late capitalism corporations to survive. One problem of the USSR is that Russia wasn't an advanced capitalist country. A dictatorship of the proletariat in the US, Japan, Germany, on the other hand, will have a pool of managerial talent to optimize production much greater then the russians had. About the cold war: once you have enough nukes conventional war is impossible. Beyond the fifties the USSR would never be able to conquer W.Europe without triggering massive nuclear war, nor NATO would be able to conquer E.Europe without massive retaliation. So, you don't really need a massive conventional army but a smaller anti-insurgency army. The USSR had a huge army for the same reason the US have a huge carrier fleet today: they are prepared to fight yesterday's wars. So, ditch the huge conventional army and focus on nuclear related weapowry. If that means orbital missile bases, hypersonic nuclear drones or 150mt nuclear torpedoes, so be it. It's cheaper then keeping a million men army. Also, you need size. A communist country should be self-sufficient in resources. There is no country in the world that is big enough to have all the resource (Russia lacks natural rubber and tropical farming. USA lacks natural rubber too, and half of the country is a desert.. Brazil lacks coal, some high tech metals and abundant oil, Australia is dry, Half of China is either desert or mountains) [Answer] ## This question makes some basic flawed premises, which make it hard for me to answer... First the flawed premise, 1. Ration Cards... Ration cards are not a part of capitalism. They are issued by the government to people, much like the [USSR](https://en.wikipedia.org/wiki/Rationing_in_the_Soviet_Union#:%7E:text=Rationing%20of%20money,-Perestroika%20produced%20a&text=In%201990%2C%20Byelorussia%20introduced%20a,certain%20categories%20of%20consumer%20goods.), [China](https://table.media/china/en/opinion/reference-stamps-chinas-second-currency/#:%7E:text=Due%20to%20shortages%2C%20ration%20stamps,stamps%20have%20become%20collector%27s%20items.), the USA even had rationing cards. And are a method that governments use to control indvidiuals economic activity. This is not capitalism. 2. Good groups share everything in common... A lot of the good post apocalyptic groups that I see barter goods and services with each other... Bartering is a form economic exchange, in other words (capitalism). ## So what is capitalism? (According to Questor) People throw that word around a lot... Most often communists. But I am never sure what they mean. Here is my definition: Capitalism is the belief that people should be free to exchange goods and services with each other without government intervention. That these so called economic exchanges are the business of the transacting parties, and no one else. Money was introduced as a medium of exchange so that I don't need to have what you want to trade for something that I want. To make it easier to exchange goods/services. ## So what then is communism? (According to Questor) Communism is where someone else (the government) is in control of economic exchanges. This is done in order to protect the working class from the evil buisness owners who are exploiting them. Of course. And everyone is given what they need... As determined by the benevolent leadership. ## Why are communist countries unstable? People are different, have different needs, wants, and aspirations. Communism tends to be too monolithic to allow individuals to get what they need/want and instead give everyone the same thing. This leads to the creation of black markets as people trade what they have and don't want to people for they don't have and want... Additionally, if you give everyone the same things. Regardless of what they do/don't do then that disincentives work. Why should I work hard if it has no impact on what I get? Sorry mate, I like most humans am self centered. I don't care about the "good of society" I care about the good of me, and my family. Society can itself. So while me working hard might benefit "Societal good" it doesn't benefit me, so why work hard? Once the leadership in communist countries realize that people are self centered shallow idiots with no regard for the "big picture" they have to find ways to motivate all of those short sighted self centered plebeians (SSSSPs) to work... This can lead to increased rations based on performance, or for doing work that no one else can or wants to do (cough cough market valuation of labor, capitalism) and/or work camps and firing squads. Neither of which is truly effective at getting SSSSPs to work, but it does lead to a lot of fake work as everyone wants to appear super productive.. Something along the lines of "They pretend to pay us, we pretend to work". Which is hard for centralized control to detect (in a capitalist society with more localized control, inefficiencies tend to be detected pretty quickly). ... I will be honest, the inefficiencies of centralized economic control isn't the real problem... The real problem is that for a communist economy to work. **To really work**, everyone has to buy into it, to feel invested in society, and work for the greater good. Which is why we can see successful communist communes. Which are robust and productive because everyone in the commune wants to be there, and wants to work hard. (They have to banish the slackers, like cough Bernie Sanders cough). Capitalist economies on the other hand don't require nigh universal buy in to work. Because you as an individual are free to do what you want to do. If you want to work? Great! If you don't want to work and starve, that's on you. You not participating doesn't really effect me. So what do you need to make communism effective? You need to have a culture where people are selfless, care about the greater good of society, for their neighbors, are willing to do hard work and share what they have with their neighbors. In other words you need a society that doesn't need communism, for communism to work. [Answer] Your question is very hard to answer for a few reasons. You ask if a communist society can remain stable, and how. **What do you mean by stability? What do you mean by communism?** Political and economic stability have a strong correlation, but a stable system is like a stable object; it is not moving. Instability, both political and economic, is often progressive because it allows systems to be redesigned. That can be for better or worse, the same as stability itself. Its depends where you are standing. If your community is stable this is good if your neighbours are degrading. If your community is stable this is bad if your neighbours are improving. Communism is as big tent an ideology as Christianity; there's a lot of variation between different implementations, and lots of people denouncing each other as being imposters, fraudsters, or revisionists. Even with a core text in both cases, we see entropy at work - as time goes by the systems fragment and break into smaller pieces. Nature finds a way by creating mutation, and our minds are no exception to their origins. Our ideas mutate over time, adding more chaos to the mix. You could write a PhD (many have) on communism, so I'm not going to try, and will discuss matters in simplistic and general terms with some historical context; all I can do is to point out some obvious errors in what many find to be common sense. A communist society is one where the means of production is owned by the people. What does this mean? Good question. It means that the factories, land, and tools used to provide people's essentials are administered for common benefit. Karl Marx's ideas were a reaction to a time when "common land" was being bought. This was a problem for many people who had previously relied upon common land for things like food, firewood, and construction materials. When the forest is suddenly owned by someone, where are you going to get your firewood from? You have to buy it. Can you afford it? Maybe not. Too bad, it's going to be a cold winter. The main communist premise is to return the land to common ownership, and the assumption is that humanity is naturally a thing of egalitarianism which we must return to. Communism doesn't have boom and bust, so it's more stable than capitalism because of that. This doesn't mean it's more prosperous; it's not. But that may not be the point at the time. It's also worth noting that many of the criticisms of "communism" are not criticisms unique to communism, or at all meaningful. If greed and corruption is a human problem which threatens communism, so too is a problem which threatens democracy and capitalism. It almost destroyed both come the Great Depression, seeing the emergence of communist and fascist revolutionaries. There's no reason a communist society can't reward work appropriately. If the collective owns the means of production they can do whatever they please with their collective surplus. This means higher pay for more skilled or necessary work, as well as overtime for longer hours, is entirely possible. It's not mutually exclusive to collective ownership of the means of production. Nor indeed is that in conflict with private enterprise per se. There's no reason people can't buy and sell products and services which are outside of the scope of the means of production. For example, an artist can sell their paintings. Their relationship to the economy is not like that of industries which provide food, transport, housing, etc. Because the latter is essential, and people are captive consumers to these industries, but the former is not. The free market is also not the most effective mechanism all of the time, otherwise we'd have mercenaries instead of standing armies. But money isn't what makes people volunteer to die for their country. Poverty may be, but often that isn't the point. People are motivated by things that aren't simply financial, especially after their basic needs are taken care of. **So what exactly would make a communist society stable? Primarily if that society was in a technologically stagnant era, with no hope of invention or exploration.** Either early primitive civilisation, or late space faring civilisation. Or somewhere along the line where for some reason technological progress and the movement of people stopped. Then, importantly, economic growth won't exist because nothing new can be invented which can change society; so society won't change. There will be no more boom or bust, just permanent stagnation. And in this situation it's best to pursue equality to guard against war between the eternal-rich and eternal-poor. [One NASA funded study](https://www.theguardian.com/environment/earth-insight/2014/mar/14/nasa-civilisation-irreversible-collapse-study-scientists) found that historically, inequality and resource scarcity are the two biggest factors in the collapse of any given civilisation. If you want a stable society your people have to value stability. If you promise them progress (instability) and get their hopes up, little surprise that decades later they will become disillusioned with a lack of progress. Have government do the basics well, and promote accountability, individual reward, and participation... or just engineer the implosion of your neighbours. HUEHUEHUE. **TL;DR** Communism is a stable system and this is why it has been a problem child. Permanent economic and technological stagnation would make it desirable, because then inequality which would otherwise tear a stagnant society apart is managed fairly. Imagine that the economy is a hermit crab, and its shell is the government's political ideology. Every once in a while society must find a new ideology to suit its growth. If the crab is still growing it cannot live within the confines of communism's large and hard shell. If however the crab has matured, then the communist shell makes sense and will protect it. The question of how this eternal technological stagnation comes about is up to you. ]

[Question] [ Imagine a world similar to medieval Earth (technologically), populated by humanoid beings. For all intents and purposes, they are humans - they talk like humans, think like humans, have human-like culture - with one exception: they are all immortal. Wars will still happen because these immortal people still have the same emotions as we mere mortals: Greed, love, lust, desire, and a host of others. They want more land, riches, jewels, power - all the things that many normal humans want. Given that they have the same inabilities to work out their differences peacefully, they go to war. The thing is, they can't die. If they lost some body part - say, a head or a buttock - that part is regenerated in a matter of seconds (say, two or three). Energy expenditure is minimal - negligible, even. Major injuries are but inconveniences to this race. There's simply no point in trying to kill people. How will these medieval immortals fight a war? I have two main ways in mind: 1. Focusing on harming the enemy as a way of trying to slow them down. 2. Focusing on destroying resources. Which path would the immortals take (and how would they go about doing it)? [Answer] # Focus on imprisoning If you are naked in a cage, you can be immortal as much as you want, you won't be able harm me (in most situations, anyway). [Answer] Others have asked and answered these questions more than 2000 years ago. Just read literature about any pantheon of gods and you'll find a lot of great patterns. * Gods can be banished (from places or social gatherings, not from a plane of existence) * Gods can be imprisoned * Gods can be tortured (chain them to a rock and send a bird every so often to eat some of their liver) * Gods can be tricked * Gods can lose social standing * Gods can lose ownership With imprisonment and torture, they have options that are similar to killing. In warfare, they would likely either use weapons that inflict pain, like fire, or weapons to restrain an enemy like nets. Cutting weapons like axes, swords, and halberds will be useful too because even if their sword arm regrows after 3 seconds, the new arm won't be holding a weapon anymore. Depending on the exact rules of their healing, poisons and weapons like barbed arrows could also be very helpful. And of course, they'll use everything that can permanently immobilize a temporarily disabled enemy like shackles, or untrained soldiers in the back that are just there to hack away at the fallen enemies. The goal of a battle will be much the same as it was in medieval times: To rout the enemy. Once one side believes that they will lose, some soldiers will run away to avoid capture, which will increase the pressure on the remaining soldiers to run away too. Inferior armies would hide behind fortifications, just like human armies of the time did, and the advancing army would develop all kinds of siege weapons to weaken or remove advantages offered by the fortifications. Wars are always incredibly expensive, and are paid for by the winning side (ideally) with the spoils of war. If there is no chance for spoils of war there will be no war, for financial reasons. Destroying resources will deny them to both sides, so that is a tactic which is much more likely to be used by the losing side, same as with mortals. **Addendum:** I feel the need to address the many answers that say there wouldn't be wars. Imagine that we start without wars. Then 10 immortals team up and figure out that they can just go to a house, easily use their superior numbers to shackle the family living there, throw the father into a well, and have fun with the wife and the daughters. Then these immortals continue to go from house to house and repeat the process until the people realize they can group up too, into groups larger than 10. Then they capture the 10 troublemakers and punish them by making them into metal statues for eternity. At that point, the immortals have figured out that larger/stronger groups can dominate smaller/weaker groups, which is the basis of warfare. Next, they'll come up with the weapons and tactics needed to defend themselves from other groups (if they're nice people), or to dominate other groups (if they're not so nice people). Since they are immortal and can presumably reproduce, overcrowding and armed conflict are almost guaranteed to happen at some point. [Answer] Death is something that is almost universally feared. Remove it, and things changes surprisingly. # 1. What people do Most people would not try to do things which have very low chances on succeding and possibly cost their lives, like trying to sneak inside the enemy barracks to steal something or so on. These things are normally suicidal missions and failure would likely result in death. Now things are different, suicidal missions could be viable in some cases (if you don't get caught). Violent sports now could became fun. Ever dreamed about jumping off an airplane (or a very high cliff) and splatting in the ground just for the fun? No problem with that. Do you like the idea of jousting without using any armor? Then, enjoy the fun. Economy becames very different. There is much less need in eating, drinking water, hunting, farming, etc. # 2. What people do to harm other people But, in order to punish someone, now you don't have limits to torture. What about throwing someone to swim in a lava lake? What about being forced to eat/drink red-hot liquid iron being pumped directly down your throat? What about being continually crushed and sliced by hundred of sawblades for some hours? Or days? Or years? People would be then punished by imprisioning and torturing. There is no limits for cruelty anymore. Wars would be fought with this in mind. Since you can't kill your enemies, you would likely focus the war into imprisioning and torturing them, and destroying things that they value. By the way, tieing your enemy to a rock and throwing it out in the deep sea or just buring them alive very deep (possibly within very solid rocks like concrete or basalt) has the same economic/political result as killing them. Nobody will ever see them again and they would not be able to do anything that is noticeable to his fellow fully-living humans. So, instead on focusing on killing and the threat of killing, the focus would be on burying people alive forever or threating in burying them alive forever, which has almost the same practical results. Fighting would be very different. Attacking someone with a sword or with an axe is useless. What is useful is trying to immobilize as many enemies as possible, and then take them away as quickly as possible for being imprisioned forever (before someone rescue them or they free up theirselves). This could be achieved with traps (like camoufled holes in the ground) or with handcuffs and ropes (preferentially metallic ropes that can't be cut out with a knife). Kidnapping becomes very important in warfare. Developing drugs that leads to paralyzing or weakness also becomes effective. Battles would be fought as armies trying to capture and remove from the battlefield as much as possible of the opponents. So being trained in martial arts that enables immobilizing the oponent as quickly as possible, like Judo or Jiu Jitsu (but on strange but interesting variations to be fought by massive teams), becomes important. Technics and tactics that focuses on trying to rescue captured friends or being able to escape after being captured are also important. This type of battle could result in an interesting type of olympic collective sport - Massive immobilization martial arts. # 3. Physics By the way, when people regenerate a lost body part, if the strange physics laws on this world don't immediatelly destroy the lost part when the larger part of the body regenerates, we have a violation of the [mass conservation law](https://en.wikipedia.org/wiki/Conservation_of_mass) which implies in the violation of the [first](https://en.wikipedia.org/wiki/First_law_of_thermodynamics) and [second](https://en.wikipedia.org/wiki/Second_law_of_thermodynamics) laws of thermodynamics. This could be interesting: By continuously dismembering someone we could create an engine capable of [Perpetual motion](https://en.wikipedia.org/wiki/Perpetual_motion), since it would be able to continuosly regenerate out of nothing the fuel that it consumes. Also, since we have violation on mass conservation law, after some millenia of raging bloody wars, Earth's mass would increase and gravity would also increase too. After some billions years, Earth would be transformed into a fiery planet where everyone is constantly being melted and/or vaporized and regenerating. When the Sun enters the supergiant branch and destroys Earth, people would then be constantly vaporized and regenerate in the Sun, and that is indeed very painfully. But this would still become worse when the Sun turns out to be a white dwarf, and that will be still more painfully. To finally make things worse, in some trillions or quadrillions of years in future, this would produce enough mass to the point where we end with a black hole full of people experimenting a new definition of pain and suffering and realizing that they really don't need to die to achieve what could only be described as having their souls being tormented for eternity in what could only be defined as hell. So, surely they [will be cast out into the outer darkness; in that place there will be weeping and gnashing of teeth.](http://biblehub.com/matthew/8-12.htm) And the black hole would still be gaining mass, which means that if the gravity gain (i.e. gravity derived over time) is greater than some formula that sums up the universe inflation and hawking radiation, this would result in a Big Crunch in some veeeeeery distant future. If the regeration happens in a way where there is no mass gain, by destroying the dismembered body part when it regenerates back into the greater body part, we essentially have some form of moving mass and performing work without releasing energy. This could then be engineered into a perpetual motion machine, although this would still be somewhat complicated to achieve, but surely doable. Since we have that energy can be converted to mass as in $e = mc^2$, we still are able to create some machine that is able to produce mass out of the nothing. Eventually, after the Sun engulfs Earth and evolves to be a white dwarf, this constant energy gain would be able to turn itself on mass gain under the strong white dwarf's gravity, and eventually (likely in quadrillions of years) be able to produce a black hole and perhaps, the Big Crunch. In fact, death is something that results on the application of the thermodynamics laws and entropy to living beings. Remove death, and you fatally violated the thermodynamics laws. By the way, does regenerating works on the speed of light? Or is it faster than light? Or is it slower than light? Or is it instantly? In each one of the four ways, interesting (and possibly paradoxical) phenomena will result when you add relativity into the account... [Answer] ## Overview No war would be fought. First, you don't have immortals. Immortals are beings which do not age or die of old age, but are otherwise susceptible to harm and death. You have invincibles, which cannot be killed under any circumstances. Despite your claim, these beings should not have greed, lust, anger, etc. Mortals hoard resources because they are necessary to *survive* and *thrive*. This leads to greed and competition. They lust because reproduction is the only form of immortality available to them. But immortal and invincible beings should have no biological imperative to reproduce, unless there is some other benefit to increasing numbers. ## History So, it matters how these beings came to be invincible, because that would determine what kinds of drives and motivations they inherited. But logically, such beings should not care about food, clothing, housing, or any other needs related to survival. They should only care about pleasure, whether by art or learning or hedonistic experience. They may develop technology, but if they start at medieval level tech, then their most advanced weapon is their invincibility itself. Even trapping an invincible may be difficult to impossible. If you chain one to a brick and throw it in the deep ocean, it could just break off its leg and regrow it. If you try to bury it under a pile of rocks, it could explode itself or even immolate itself to escape, literally in a cloud of smoke. And technology may well boil down to various ways to attack not one's enemies, but *oneself* in order to avoid an unseemly fate. This would be a rather peculiar state of affairs, to say the least. ## Tactics Thus, any kind of conflict would center on imprisonment, as others have noted, but especially on *escape*, which may defeat capture/imprisonment entirely. Such beings may simply choose to embed a bomb inside their own bodies so that they can detonate at any time, making it nearly impossible to truly trap them. ## Conclusion Since scarce resources are meaningless for survival, at most, such beings would compete over art and pleasure. Learning would benefit most from cooperation, and is generally not zero-sum. Even competing over resources to, say, build musical instruments or theaters would seem petty and small-minded for such powerful beings. In fact, it is hard to believe that such beings would want to do anything other than advance their technology to match their innate abilities, and this would be accomplished quickest by cooperating. Strong leaders would not exist because they can guarantee *survival* or *riches*, but simply because they would give people *something to do*. Boredom would be the biggest danger in a world of such beings. This is why intellectual advancement is the most logical pursuit. How they came to be so powerful with so little technology to begin with might be the defining question of their time, given that nothing else in their world is as durable as they are. [Answer] If a full war were to be waged, I would imagine it would go on for quite some time, until one side is eventually capable of [imprisoning](https://worldbuilding.stackexchange.com/a/25661/2138) most of the other side, as @Lohoris suggests. However, after the results from that war, I imagine immortals might be loathe to try and resolve difficulties in such a time-consuming and painful method in the future. There could be a number of different ways immortals might decide to resolve conflicts instead: * Duels * Vote by Popularity * Luck-based contests or gambling * simulated war via mortal proxies (*If any suitable animals may exist*) [Answer] You say that these people is like humans. No immortal would be like a human, since our mortality is a cornerstone of everything that makes us human. There is no reason for these people to feel pain. Pain is there to stop us before we do something fatal. No fatality, no pain. There is very little for these people to fear. Fear is there to stop us before we do something that would be painful. No pain, no fear. There would be no need for these people to be *social* at all. Human originally banded together for mutual protection. These people have no need for protection. Military discipline would be impossible. It is built partially on the mutual protection idea and partially on soldiers fearing their officers more than they fear the enemy. No need for protection, no fear in general, no military. These people aren't anything even remotely close to human, and it is impossible for us to guess how they would behave. [Answer] They don't need resources to live so destroying resources has no effect. They cannot be slowed down at all for more than a few seconds so hacking limbs off is ineffectual. Even if one were completely dismembered they would simply regenerate as soon as they are left alone for 10 seconds. Torture is no good since they cannot die and cannot elect to commit suicide. Imprisonment is ineffectual since it takes additional resources to mind the prisoners and given they are immortal, statistically speaking they will eventually escape, unless:: **Second Edit:** Actually you can disable an immortal permanently by casting him or her into the heart of a star or gas giant, and somewhat less certainly by dropping them onto any other planet from which gravity well they cannot escape. If the immortals develop technology which could overcome these gravity wells, then your only remaining recourse is a black hole. I do quite like the idea of: # "immortals riding space-dragons wrestling on the event horizon of a black hole at the centre of the galaxy at the end of time (TM)" [Answer] 1. Capture them; 2. Chop them down as fast as you can (5 persons chopping a limb at the same time should be enough... trial and error); 3. Immediately stick their stinking regenerating body parts in small and strong metal cases; 4. Drive them as far away as possible in different directions and bury them deep in solid rocky ground; 5. Cover each of the burial places with large enough stones. That should make their immortal arses quiet for a long time. [Answer] They would cut themselves in half so that each half grows back to the original. Exponential growth will then allow them to overwhelm the enemy. At least this is how the immortal microbes go about their business. [Answer] **Immortal, not invincible...** My line of thought/questioning differs from existing answers which focus purely on physical imprisonment and psychological warfare. Instead, depending upon the mechanism of healing it may be possible to disfigure (and disable) your enemy instead. I also suggest that it may be possible to disfigure yourself to your own advantage. **Disfigurement via damage/healing cycles** For example, given a partially broken bone or other similar internal injury, the healing process may be influenced to heal in abnormal positions - for example at a slight angle. Repeat ad-nauseam and it may be possible to encourage a poorly-healed limb to rotate upon itself and/or in weird and wonderful directions and shapes. **Embedded "stuff"** Given that healing process may be perfect at repairing/adapting bodily function, it may be possible to embed "stuff" within a body (for example a bullet), then have the body heal around it. Presumably the healed body would have the same mass, with the addition of whatever is embedded. Repeat a few times until the immortal being exists as a skin around a solid "core" of embedded 'stuff'. Do this with all body parts and slightly larger items than a bullet and it would be possible to configure a body to be much larger in size than a normal human. **Combining the above for the offensive - GIANTS!!** By using repeated breaks/repairs to extend limbs (instead of deform them) and the packing of "stuff" within a body, it seems feasible that by taking advantage of the healing processes then giant beings can be created. **Drawbacks** * Given the ability for severed limbs to heal back perfectly (with the severed part(s) disappearing), all it would take is for a deformed being to be restored is to systematically remove various body parts for them to be replaced "as new", undoing the earlier disfigurement/disablement work. * Presumably pain would only be felt for a second or two while injuries/wounds heal, but this may still be a significant inhibitor of self-inflicted disfigurement. * It is an assumption that the partially healed areas and stretched areas of flesh would increase in strength/capability. I suggest that this seems reasonable in the case of muscle where strength is increased in normal humans via repeated small tears and repairs. [Answer] **Focus on Psychological Warfare** If you can't kill an immortal, it's effectively the same as if they have really amazing armor. The Art of War dictates that you shouldn't make frontal attacks unless you have overwhelming force. There is no such thing as overwhelming force to a person who regenerates a body part in seconds. You have to make them not *want* to fight you anymore. Demoralize them so completely that they simply cannot fight anymore. > > Hence to fight and conquer in all your battles is not supreme excellence; supreme excellence consists in breaking the enemy's resistance without fighting. > > > ([Art of War, Section 3](http://suntzusaid.com/book/3)) **Outsmart them** It is instantly obvious that open, frontal attacks in these circumstances are pointless so don't do it. Attack them sideways with methods they don't expect. * Be where they do not expect. Move your armies in such a way that they do not or can not anticipate where you are or will be. * Anticipate their plans and preempt them. Having spies and moles in their organization will make this much easier. * Build an economy that out-competes theirs. Pursue any and all economic advantages. Business is cut-throat already. Economic warfare among immortals would be especially bloody. [Answer] ## This Is Why We Can't Have Nice Things If immortals themselves can't be usefully harmed directly, and if you're tired of the "what if we put them through a wood chipper over and over again..." shtick, let's consider the next big issue: if these immortals are like humans, ***they care for things other than themselves.*** Pets, plants, houses, gardens, gifts they were given (or are working on to give to someone else), monuments, relics, symbols, etc. These things are all anything but immortal, and just as humans can care for things they know won't last their whole life (pets with short life spans, flowers, even other mortal humans), these people should care about something. Sadly, in a state of war, these things become the primary objectives. If you can't destroy your enemy, destroy what your enemy cares about. ## Pillaging, Razing, Raping, and Looting Your immortals should tend to want to defend the things they care about, rather than merely themselves. **Some immortals will just want to watch the world burn**, having given up on caring for anything impermanent and inferior, while others will likely come to hold the idea that just because something won't last forever is no reason to let it be taken away prematurely. Greed, jealous, and envy should also still exist. Why do those people get gold-plated crowns and comfy chairs - what, do they think they are better than us? ## Everything has a season and a time We can enjoy it while it lasts, grieve, and then move on to the next experience, and your immortals should understand that - again, all the more reason to develop, build, and protect what you care about. Some will want to hurt others by taking away these things, and some will fight to protect what they have. ## Get them before they get us Just as humans have problems with pre-emptive attacks, your immortals should too. Sure, the Others SAY their forge is for creating building materials for their city, but that "column" sure looks like a potential battering ram to me! And are those hammers for building, or war hammers? Your societies may tend to think the other guy is working on siege weapons (weapons of mass destruction), and if they have the facilities they need to build weapons of war then you'd better have some of your own too. Fear leads to arms races, and arms races lead into escalating conflict - and war. ## Siege Weapons Are The New Primary Weapon Given all the above, why should immortals care about pointy sticks? Sure you can slow down the others, and that will have some value (hacking off legs, pinning them in place temporarily with a big spear, etc), but that's just a means to the new end - destroying stuff. If the goal of the combat moves from "killing and maiming" to "breaking and burning", the weapons they choose and how they conduct warfare should change more dramatically. Historically siege weapons were not so extensively used for this reason, but with the focus now being on 'things' instead of people siege warfare should see a new golden age! I imagine hammers, ballistae, flaming weapons (arrows, pots, etc), catapults/trebuchet, hammers, and "area denial" weapons (raining arrows/rocks/shards/fire/caltrops/spikes) will be thrust to the center of the action. You'll still need cutting weapons, but you also need a new strategy: how are you going to make off with the goods in a hurry? I imagine speed, mobility, and carrying capacity will be a big concern. What good is raiding the enemy city if you can't carry off their giant golden phallic objects? You need wagons, maybe horses (uh oh, those aren't immortal...), and probably other developments that were not the norm in the middle ages. ## Cue Gunfire and Explosions Remember, too, that cannons and gunpowder are achievable in the middle ages - and in Europe this was not so important partly because of how war was fought. But if hurling a big iron ball hundreds of yards, or making things explode in flames, suddenly becomes more important than accurately hitting individual people, why wouldn't they emphasize it's development much more than historically was the case (and thus more like some of the advancements made in China for other reasons)? Rockets, incendiaries, the rediscovery of Greek Fire (or it never having been forgotten), boom boom boom! All are suddenly very attractive to immortals! Armor and long bows - **boooring, let's blow some stuff up!** ## Maybe they can just use foul language With physical necessity out of the way, things are going to be even more heavily culturally and emotionally influenced than they are now. If war isn't about killing, it might very well commonly be about sending a message, proving a point, taking the other guy down a few pegs, proving your groups superiority, and so on. Suddenly insults, foul language, and other such 'psychological warfare' can take on new meaning. If sticks and stones breaking your bones can't hurt you, maybe words will! Now go away, before I taunt you a second time! [Answer] On a meta level, war is "politics continued by other means", and politics is defined in Organizational Theory as a "means of allocating resources". Since you cannot kill the enemy, you need to attack their will; borrowing the maxim of Sun Tsu that "Supreme excellence in war is subduing your enemy without fighting a battle". So the question becomes how do you convince or persuade the enemy that you should have the resources under contention? Using logic, battles of wits, puzzles, appeals to emotion, deception and all the other tools and tricks that are deployed by modern PSYOPS would become the means of waging war. The Russians have used this to great effect in Ukraine and Crimea, ISIS uses it in tandem with their other tools of war and the Chinese are using this to some extent in the South China Sea. Great commanders in the past have also been able to win victories by essentially outthinking or bluffing their enemies (a good example to research is Sir Issac Brock's capture of Fort Detroit in the War of 1812). While thinking of warfare as a form of advertising or persuasion may seem startling, messing with people's minds in the service of war is probably as old as warfare itself. Think of a Maori *Hakka* to imply ferocity before a battle, or the reciting of pedigree and heroic deeds by the heroes of the Iliad or Japanese Samurai prior to a battle. The analogy is imperfect (after all, you are still setting up to kill your Trojan or enemy Samurai opponent by unsettling them), but it is a good way to think of things. [Answer] Similar to the simple answer of imprisonment, **you have to also catch them**. **Trap** I propose a series of traps, such as the *trou de loup* method. A large, covered pit where they are trapped and then sealed by rocks and morter that they cannot lift or move. Keep them in there as long as you like. [Answer] I can actually think of many ways for them to "enjoy" wars, but in the long term, since they are immortal, they'd learn that wars achieve nothing. Let me explain: if they **know** they are all immortal, they will probably focus on a guerrilla with ambushes and imprisonment rather than anything else. Maybe kidnapping and maybe sabotage (but hey, even if they are greedy, they can anyway live without crops, right?). So after a couple generations the war will reach a standstill, where factions simply don't go in some territories (fear of being taken by the other faction and spend the eternity inside a volcano?). Eventually their arrogance and ignorance (they are human-like, right?) will make some people think that **they** could instead reign, so I would focus more on "secret" civil wars, kidnappings and tortures rather than a proper war. [Answer] I think you have overlooked a central issue -- war by definition is a large scale organized affair. This organization in our world is motivated in part by fear of death and limited resources -- join our group or we kill you/your family/crops. This motivation will be absent from your immortals. This will make large scale fighting organizations (armies) much harder or even impossible to form. They may do them for fun or for idealogical reasons, but consequentially will be considerably smaller scale than what we think of as war. More raids/cattle stealing/counting coup than war. This does not totally eliminate "war" as politics by other means, it does change how it is used and the scale. [Answer] I guess it depends how many times they're willing to lose a buttock or some other body part. It would just be a staring contest [Answer] ## BIOLOGICAL WARFARE would be appropriate Expose your enemy to a hazardous biological weapon (virus) such that they lose their ability to Move.Immortality is worthless if you are paralysed. [Answer] 1. Eternal imprisonment 2. Eternal pain & suffering (a real Hell) What would be worst than that? e.g. Phantom Zone (Superman II) The bad guys were imprisoned in the Phantom Zone, a prison were people can never get old or die. [Answer] I would say until weapons of mass destruction occur (say something that fully incinerates the body, say a large incendiary bomb) That most of them would turn to chess like political 'games' for 'winning' and losing. If it is almost impossible to kill your opponent, then 'other' ways will be needed to 'beat' them. I would expect a most Byzantine politics arise with an almost unfathomable score keeping to emerge. Since if violence is ineffective, other than pissing off your opponent, then it would fall by the way side as a means to an end. A show of violence, especially from an uncontroled outburst, would appear to be a childish reaction with no point or merit. Of course, if I really wanted to get rid of one of these people because I felt they just had to go, I'd find a way to render them unconscious long enough to throw them under a lava flow. It would be the perfect prison to keep them for millenia. [Answer] Maybe one group would try to influence the other group to submit to their ways. Psychological warfare would be more damaging than actual wars in that case. [Answer] In effect, Philip Jose Farmer's "Riverworld" explores a similar theme, as each death seems to be followed by reconstitution of the continuous self, elsewhere along the river. As to the question, as in chess, or ancient Egypt, were one fortunate enough to be King, or living god. [Answer] Make them ugly, like the Gollum in the Lord of the Rings, that should be your target. After the war, when they look in the mirror they should hate themselves. They will fear your acid or chemical weapons which make them ugliest in the world than the 'imprisonment'. If you are imprisoning them, there is a chance for escape in a long run. But if they are ugly and loss their self identity then who will want to be immortal? So you should fight with such kinds of weapons and ideas( for example, fry them in frying pans, put them in oil and burn, inject viruses, etc.) [Answer] I'm going to assume they still need to eat and drink or they'll get weak, but not die so burning and salting fields and polluting water would be a good idea, but if you want to win a war you need to find a way to stop them. Digging deep pits to throw the enemy into and then filling it with concrete or glue or even rocks would prevent them from getting out (at least for a few hundred years). I think it'd become a war of traps and capturing instead of killing. [Answer] If any are beings of honor, trapping them in a promise, a la Superman in the Frank Miller Dark Knight graphic novel. Hurting the ones they love. Protecting the ones they love in exchange for concession of defeat. (Or anything else that can leverage them into submission. What happens to all of those severed immortal limbs? How many of the same head can be accumulated? (rhetorical questions). Torture still works, even if they can't die, just ask Prometheus. [Answer] Immortals can't die. Any combat will be non-lethal. Establish appropriate rules of engagement on both sides. The soldiers on both sides line up, face to face, one on one, and play rock, paper, scissors. Which side wins the most number of rounds of the game is the victor. ]

[Question] [ "Magic and science coexist." A tired phrase by now, because it's found in so much fiction. But can it make sense? Assume a world broadly parallel to our own. It has experienced its Age of Enlightenment and Industrial Revolution. There is also magic (type yet undefined). It should allow human magicians who cast spells, whole species that are magical in nature, locations and objects with persistent magical properties. The usual stuff. The Masquerade is not in effect. It is, and always has been, impossible to keep a fundamental part of the nature of the world secret. **How to keep magic separate from science?** "Science" includes many fields of study. How to make it such that magic is not one of them? How to make magic resistant to study by experimentation? Science must be "logical" and "rational" and magic not. A person with a rational mindset should not look to magic as the first answer. Why? And how and why would the scientific method ever have developed if a major part of reality was resistant to it? I left the nature of magic open because that's an inseparable part of the question. **What type of magic could fit this world?** Is there any magic system that can make sense here? *I've asked this question on other sites before. A couple important points resulting from that:* *Magic can't be totally random, since it must be possible to control it to some extent, or there could be no magicians.* *The suggestions I previously received that came closest to satisfying my requests hinged on irreproducible results. These permitted spellcasting, but ruled out the other aspects of magic.* [Answer] I think the mistake you're making here is trying to categorise magic as something which is profoundly "not science". If we boil down "science" to simply be the processes that we use in order to further our understanding and manipulation of natural phenomena, such as trial and error, or rigorous analysis, then there is no reason these cannot be applied to magic. In our own world, we typically try to use science to understand basic hows and whys. For example, how do two chemicals react when thrown together in a vial, and why do they do that? By doing so, we discover the laws which the natural world follows. These processes can also be applied to magic, except when the magic does not have rules. That would make it very dangerous indeed, and quite frankly, something you'd probably want to stay away from rather than study. So, unless your magic system has zero rules, to some degree or other, it is possible to apply scientific reasoning to it. What then, discerns magic and science? We could draw in Aurthur C. Clarke's third law here: Any sufficiently advanced technology is indistinguishable from magic. By that, you can take "magic" to be anything science fails to understand. Therefore, if you wish to have hardcore science and magic co-incide, there should be some core aspect of your world's magic which cannot be explained by science. Using that logic, magic technically exists in the real world, and simply represents things which we understand to be "base rules" or causes, rather than effects. If that is not appealing, you could create a magic system which encompasses sizable differences from our world. For example, if all humans in your world are capable of manipulating traditional elements, (fire, wind etc) you could consider that your magic system, even if it has been largely explained by science. Remember, your readers come from this world, where such things do not exist, and thus they seem magical to the readers, regardless of how they seem to your characters. [Answer] **If magic has effects in the natural world, it will be studied by science.** This isn't really escapable, science can study anything with observable effects in the universe. If magic is a well known force, humans will attempt to understand it through scientific observation. The best you can do is make magic so rare that few people believe in it or have any opportunity to study it. Then it would look much as the world does today. Separation doesn't seem that important. Science is not a thing, force, or entity. It's the *study of things, forces and entities*. It's a method humans use to understand all the things which happen in our universe, to put something outside of science is to say it has no observable effects on this universe. Thus, if magic is real, it *will* be studied by science. [Answer] ## Magic? Surely you mean Thaumaturgic Engineering! An important point: **engineering is not science**, and science is not engineering. Engineering may use science, and science may use engineering, but the two are not identical, and often even dissimilar in scope and purpose. We were able to use many properties of reality long before we were able to get a near-complete mathematical description of the underlying principles. You can be sure the Wright brothers had not worked out in detail the Aerodynamic properties of their machines before taking off, although I think they *did* build a wind-tunnel. We knew how to make **gunpowder** (and made, and used a lot of it) long before we understood the chemistry of rapid oxidation. In a similar way, magic could be employed productively and on a large scale without being completely, or even partially understood. This would be done in the same way technological progress was made before the advent of theoretical scientific advances: trial and error, filtering out what works from what doesn't. Encyclopedic and procedural knowledge, rather than theoretical and formulaic. ## Not Another Physics Sub-Field! Magic is generally distinguishable from physics thanks to a few characteristics. In popular lore, magic tend to rely on sympathetic principles or contagion principles. * Sympathetic: Like affects like. The voodoo doll somehow `captures` your liking, and thus gains power over you. There is no other visible causal association, so a hidden Jungian psychopomp mechanism must be at work. In other words, the source of magic somehow reads our minds, and if the conditions of similarity are properly met, the effect is transfered across the imaginary link. * Contagion: Hurk was great warrior. You kill Hurk, eat his heart, become greater warrior. Or the creation of holy relics by sheer physical proximity to a powerful source of magic or holiness. As you can see, these are not exactly physical characteristics. The sword in king Hurk's grave should be atomically similar to other swords, but its **psychic context, from a human perspective**, imbues it with some of the strength of the warrior that used to wield it so well. So the language of magic is usually based on one of these principles. It must have its own **internal logic**, otherwise magical effects would be random, and so every yawn susceptible to summon a horde of demons. In that sense, it would be vulnerable to scientific inquiry: the basic correlates of magical operation could be discovered, and refined to a degree. However, insofar as the efficacy of the two paths described is a function of a psychic correlate (**entering an ecstatic state to achieve the symbol -> target mapping via symbolic contagion or similarity**), it may not be easily reduced to repeatable mathematical equations, and in fact will likely be even less understood than human psychology is currently. ## So how do I escape the grabbing clutches of Science? Magic is sympathetic, empathetic, holistic and irreducible. The **sympathetic** aspect requires a certain kind of mind, drawn to symbols and metaphors, people with a rather tenuous grasp on 'normal' reality. The **empathetic** aspect requires a highly emotive personality, the opposite of the analytical mind, but is vital for successful symbol-target binding. Your best friend here is the holistic aspect. It requires the practitioner to $$\Large\textit{enter an ecstatic trance-like state}$$ that is almost wholly right-brained, where the details of what exactly they do are lost, and the hole endeavor is **holistic**, where the whole effect is lost if a single part is removed, and thus **irreducible**. Why does it matter that the naked dance must start *clockwise* under the full moon? Who can say. But it works no other way. [Answer] # Keep Your Science Off Me! There could be various cultural or other reasons for science not to study something that decidedly calls itself magic, such as: 1. The magic is practiced by some sort of priesthood, and examining it would anger the god(s) causing magic to cease or other bad things. This may or may not be true, but the idea is active in the priests/scientists heads. 2. The magic is practiced in another society which science does not know of, or the culture of the culture with science does not consider magic worth studying. These barriers can be geographic or cultural. 3. Magic can not be studied. Perhaps its fundamental to the magic working; it requires faith or simply "no observations" of its inner workings, else the magic ceases to exist/function. 4. There are no tools with which to study magic. (That is, the scientists cannot detect anything because magic is undetectable or immeasurable by the available tools.) Scientists sometimes suffer from their own [cultural bias](http://en.wikipedia.org/wiki/Cultural_bias), leading them to incorrect conclusions or simply poor science. Eliminating and adjusting for biases is part of a scientist's job. Everyone who does any science need to acknowledge biases. You can take advantage of this in your world. # Rules of Magic You can have several types of magic work in such a setting. This is especially true if there are simply cultural or geographic barriers between the magic-users and scientists. This can also work if magic is a relatively new or hidden thing, so that scientists cannot experiment upon it. Your rules of magic could also vary from a group or individual to the next. This results in magicians but no formal rules for everyone. This would stymie most scientific investigations, because you can always find a disproof of any hypothesis. Reproduction of results is important in verifying and establishing theories we use to describe the world. The study of magic would be reduced to "there are sometimes rules," which does not really count as good science. [Answer] Why must science and magic be kept separate? Make magic a fundamental force of nature, with its own rules and manner it can be manipulated. Scientists can study the power, They know how it is produced, have SI units to define it's power levels, and measure its uses. In the future machines that utilize Mana as a power source will be as common as our machines that utilize electricity. In essence there should be no distinction between magic and science, no more then we consider electromagnetism to be some special ability separate from science. It's a force, it does lots of really cool things, and science has worked to make it do more. The only difference is that humans have a natural ability to shape magic without technology in your world, whereas humans can't do much to create or modify electricity or magnetism without technology. If you want to keep some level of distinction between magic and science in your would, just claim that your present day scientists have not fully articulated or defined how magic works, just as those in the Age of Enlightenment couldn't have defined what caused lightning bolts to hit, or how to protect their houses from them. Our science has only defined parts of magic yet, and much is still unknown. However, long before we known how photosynthesis worked we had plants and greenhouses. You don't have to have full understanding of the world to work within it; in fact, we will never have a full understanding of the world, just increasingly better approximations. It could be that scientists are still working to fully understand how magic works, but that doesn't stop magicians from using the magic as well as it's currently understood. [Answer] The answer is quite easy: There are instances where science can only make general answers because * **the result depends on *too many factors*** To experiment with something, we need to hold some factors constant while we are able to vary other factors and see their influence. If there are too many factors, it is very hard to make general conclusions. Social science and medicine have a severe reproducibility problem because *humans are so diverse*. There are substances ("unsafe" ones) which could kill one patient while having a neglible effect on other patients. We have age, sex, size, weight, health condition etc. and even if you do exactly the same procedure to patients, the results can never be exactly predicted. Thus medicine needed meta-analysis, a statistical tool to get an assessment out of studies with different results. * **the result depends on *factors which cease to exist when we try to examine or replicate them*** This may sound funny, but it isn't. It happens e.g. that a motorbike shows a phenomenon only when we drive it; when we stop to look at it, it disappears. Because we cannot disassemble the machine while we are driving we are stuck. Another example is tribology, the science of friction. The problem is that "normal" friction happens with dirty, individual substances. Your shoe, freshly filled with gravel, on a parquet floor has a very wide span of possible friction values. When I try to nail down a more precise value by cleaning it, I may get a better one, but it is not the "correct" gravel-shoe-on-parquet value anymore. In quantum physics we have the problem that when we try to make a certain physical value as precise as possible, another linked physical value will get as *imprecise* as possible. * **the result is *too rare or too individual* to get meaningful answers** Freak waves were considered a yarn until they could not be negated anymore. They are very rare and they likely kill the observers, so their existence was doubtful. Your magic could be very individualistic, so that one apprentice cannot for his life conjure a small amount of heat while another one burns without sweat through a steel door. Even then science will get to some very, very general conclusions: Magic exists, the effects can be observed, but trying to find some general observations which are always true can be a royal pain in the ass. **ADDITION**: I see some people have problems imagining it, so I will now give an example of magic which will be almost completely inaccessible to rational scientific observation. On the world Paradoxis, magic and science exist together. The scientists and engineers are making observations and products which work the way we know: They are consistent and reliable. But Paradoxis also knows magic: It seems that sentient beings can influence their surroundings by a strange force. Some people are quite adept at it while others struggle with it. Its influences are innumerable and well-observed and documented: Molecules change their form, their temperature, their consistency. People can move and levitate objects, start fires, cool things down, speed up or slow down processes. What is interesting is that people doing magic need to "synchronize" their attempted magic with the environment, the time and location, with themselves and observers. They get in a meditative state and "feel" what is the right procedure and what is wrong; the mental procedure itself changes every time an attempt at magic is made. Sometimes they feel magic is now impossible, sometimes it is possible to make several conjurations at once or strengthen the effect. But whatever the effect is, it is never exactly the same one. The scientists have an impressive database of observed magic, but no one was able to get any consistency out of it, so most of them gave up. [Answer] All right. This is a very good question. And there are some very good answers. Smart, thoughtful answers. But, given the way the question is stated, it feels like those answers are still thinking inside the box. In general, magic is treated as if it were nothing more than a branch of physics. **@Samuel** nails this reasoning very nicely: > > **If magic has effects in the natural world, it will be studied by science.** > > This isn't really escapable, science can study anything with observable effects in the universe. If magic is a well known force, humans will attempt to understand it through scientific observation. > > > And **@dsollen** describes the inevitable outcome: > > Make magic a fundamental force of nature, with its own rules and manner it can be manipulated. Scientists can study the power, They know how it is produced, have SI units to define it's power levels, and measure its uses. > > > It's a pretty rich and fascinating way to consider magic. +1 to both of those answers. I think they are entirely correct. Entirely correct... **as long as magic is understood purely in terms of its physical manifestations.** But physics is not the only human model of reality. There are other modes of experience. Other ways to think about what **"magic"** might be. Pardon the little thumbnail, but anything that would do van Gogh's *Starry Night over the Rhône* justice would be a massive download.  I'm not going to *dare* anybody to try to use physics to explain the impact of such a painting. Because that's just luring people to be silly to make a point of some kind. **Art and poetry are not about physics.** Neither are love, tragedy, horror, or transcendence, or mystery; or more subtle concepts such as "liberty" or "ennui". But they are all a rich part of human existence. We live them, or at least we understand, to some extent, when we hear them told. That's really the point. **So why do we want to force *magic* into the mold of scientific reductionism?** Consider magic in fiction. Here's something from [The Face in the Frost](http://en.wikipedia.org/wiki/The_Face_in_the_Frost), by John Bellairs: > > He looked absently around the cellar as he waited for the pitcher to fill, and suddenly his eye was caught by the fluttering of an old cloak hanging on a wooden peg. And in that instant Prospero got the odd notion that the cloak was not his, and might not be a cloak at all. He stared intently at it as the fluttering of the garment became more agitated. And then it turned to meet him. With empty flopping arms it floated across the cellar floor, swaying in a sickening nightmare rhythm. Prospero clenched his fist and felt his pulse beating in his palms; he fought the rising fear as the cloak flapped nearer, for with all his heart he did not want it close to him. As it closed the gap between them, all the spells against apparitions ran through his mind, but he had the queasy feeling that none of them would work. The thing was about six feet from him, its cold musty-cellar breath faintly brushing his face, when it simply stopped. The flapping arms dropped, and the gray cloak, or whatever it was, slumped into a ragged heap on the stone floor. Prospero stepped back nervously and stiffened as he felt a cold sensation. But when he looked down he laughed abruptly, since he had stepped into the spreading brown pool of ale that was now sloshing and frothing over the sides of the pitcher. He shut off the spigot and leaned, trembling, against the barrel, his forehead pressing the fragrant wet wood. When he looked again at the place on the floor where the cloak had fallen, he was not surprised to see that there was nothing lying on the rough candlelit stone. The peg where the cloak had first hung was not there either. > > > This is serious, consequential magic. But it's not physics; it even ends by *withdrawing the physical reality* that the entire terrifying scene purported to represent. Still, Bellairs leaves us no doubt about the serious peril and horror it represents. And there's this, from E.R. Eddison's [The Worm Ouroboros]: > > When that was done, yet more biting seemed the night air and yet more like the grave the stillness of the chamber. The King's hand shook as with an ague as he turned the pages of the mighty book. Gro's teeth chattered in his head. He gritted them together and waited. And now through every window came a light into the chamber as of skies paling to the dawn. Yet not wholly so; for never yet came dawn at midnight, nor from all four quarters of the sky at once, nor with such swift strides of increasing light, nor with a light so ghastly. The candle flames burned filmy as the glare waxed strong from without: an evil pallid light of bale and corruption, wherein the hands and faces of the King Gorice and his disciple showed death-pale, and their lips black as the dark skin of a grape where the bloom has been rubbed off from it. The King cried terribly, "The hour approacheth!" > > > This is a short excerpt from a description of classical Alchemical sorcery, rendered in Eddison's masterful Jacobean prose. Its impact, its significance, has nothing to do with physics. It's pure wordsmithing magic. So, to answer the question: Consider the possibility of a world in which reality, occasionally, perhaps not very predictably, responds to the same kinds of impulses and influences that art and poetry exert on human consciousness. Consider a world that bears that kind of wonder. [Answer] **Magic as an Art** One possibility would be to approach this difference not as a fundamental difference but as a difference of practice. In the real world, we tend to draw such a distinction between science and art. Art can be studied, and in many cases described by science. There is science behind the nature of sound, science behind appealing compositions of color, and even science that analyzes what comprises an appealing composition of music. Despite all this, we do not tend to view the creation of art as a science so much of as a craft. A sculpture is created not by looking at the science describing its internal structure but rather by fusing years of practice and hard work mastering a craft with an inner artistic vision. Magic could function in a similar way. Science can look at the effects of magic and describe how a sorcerer draws energy through the earth, but knowing how all of these things occur does not give one mastery over magic, any more than knowing the science of sound makes someone a maestro on the tuba. Magic can be *described* with science, but ultimately the practice of magic is learnt through decades of hard work and perseverance in shaping the mind and body of the magician to perform it. For some people, knowing both the practice and the theory behind magic could be appealing, in the way that some pianists may enjoy knowing the theory behind why certain chords sound the way they do, but knowing the theory is by no means a requirement to being a skilled magician, particularly if spells can't be cast quite the same way every time. Casting a spell would be a combination of being able to see the flows of magic around the wielder, having the intuition to see what kinds of effects those particular energies could have, and having the skill to carry out that vision. It's possible that someone skilled in the science and study of magic could construct devices that could be used to do magic, much as a scientist can mix paints or build a piano, but these items would be useless unless placed in the hands of a skilled magician. A grand unifying theory of magic that would enable a scientist to actually build a device to *do* magic may also be possible, but requiring such a high level of knowledge and technology as to remove it from the realm of possibility for the next few millennia. [Answer] **What if the universe always works your way... But only for you?** People tend to assume that rules define how everything works. That is to say: (Rules/Reality) -> defines -> (Magic/Emotions) For example, because of the exact position of every atom inside my head, their energy, and the set of rules known as physics, I feel happy today. Or: (atom+position+energy+physics) -> defines -> (happy) But this becomes problematic very quickly. What about philosophical things, like "free will" or "choice". Are we actually incapable of influencing the world around me? Do we have a set, inescapable fate? **What if it doesn't work this way?** --- Instead, let's try this: (Magic/Emotions) -> defines -> (Reality/Rules) For example: Because everybody expects the sun will to rise tomorrow, it will. (expectations) -> defines -> (sun rise tomorrow) So a "magician" is capable of influencing small amounts of reality, by **refusing to believe the world works how it *should***. This allows them to create incredibly paradoxical situations. Since scientifically-minded people understand very well how the world ***should*** work, they become **incapable of witnessing magic** that they don't already expect to work. --- From the scientists' point of view, the universe follows well known *rules*, and responds as it should. They are incapable of understanding Magic. From the Magicians' point of view, the universe is *pliable*, and they can break any rules in any way they desire, so long as they manage to overthink/overpower the minds of those around them. From the layperson's point of view, both sides would be correct, to some extent. The layperson doesn't understand enough of the world to disprove either side, they are capable of witnessing anything, since they don't think anything is impossible. Obviously, these "laypeople" don't actually exist. People would have various degrees of belief, somewhere between the two sides. **This is how our world works**, although it is currently dominated by scientifically-minded people. --- Is the universe defined by how we think it works? Or are we defined by how the universe works? *These two conflicting schools of thought are the very basis of science and magic.* **Of course they can't get along!** [Answer] I think pretty fundamentally, there's a misunderstanding here. Science isn't a set of beliefs or a faith. It's a process. It's sort of like the recipe for making a cake - you put in the ingredients, follow the directions, and out comes a cake. Science is a method - you follow the process, and you get a conclusion. Sometimes the conclusion is flawed, but sometimes your cake doesn't rise. Magic... well, that depends what magic *is* in your world. It's not inherently at odds with science though - scientific method can be applied to anything - that's why it's so amazing. I would imagine that 'magic colleges' aren't so much about magic, as they are about understanding in detail the rules and mechanisms to do it reliably. Which sounds pretty scientific to me. The only things really resistant to science in the 'real world' are also the things that don't work. It's extremely hard to exhaustively prove that e.g. homeopathy doesn't work. You can only say that for every scientific study that has been done, there have been no results that indicate that it *does*. With magic 'working' that wouldn't be the case. If enough people 'used' it, you'd have a statistical sample that - even if magic were generally a bit unreliable, you would still be able to observe and measure the outcomes.  So I would suggest the only way you could do this is to apply the 'guild method'. Accept that scientific study *will* work on magic, but seek to actively subvert and conceal the truth. If anyone 'knows' the truth, get them to join the guild, swear a (magical?) oath of secrecy, or ... ensure they keep their silence. (magically? Or just kill them). Keep 'science' as part of the 'arcane arts', and baffle the normal populace with mysticsm. [Answer] I think @PipperChip's answer is getting at the same ideas as mine for the most part. Science is just a method of looking at the world; there should be a scientific way of describing all events even if the scientific community does not currently accept the way things are. Which is completely likely and probably your best bet; that the effects of magic are thought to be explained by the scientific community as being something else and the explanations dealing with magic, even if you do have strong evidence and experiments that can be done, would destroy ones career to do such that no scientist would ever dream of doing them, or at least of publishing the results if they do not conform to the reigning orthodoxy. There are, unfortunately, actually quite a few examples from history where this was the case; where a theory or a person had such influence that until the death of the main backers of that theory no new theory could be advanced. The other thing to look at is the way that some religions view the situation of duality, and even the existence of magic, such that the primary existence of God is not to be seen in the effects of the world that science studies but in the internal nature of things. See for example hermetic alchemy. Which gets to yet another possibility, again going back to religions, that science is again studying effects where as magic could be effecting primary causes. In which case it wouldn't be that science couldn't study magic, it would just not be in a position to do so currently. Of course, even in those cases it would seem to be possible and even needed to use something of the basis of the scientific method for the development of the art of actual magic. Consider the staying power of Aristotle's theories and that I am drawing these last two examples from religion; where powerful orthodoxies that last for generations are more the rule than the exception. It is entirely possible to structure real magic such that it could be controlled in such a way that an orthodoxy controls it, and if belief or purity or something of the sort is required to access it the control could be effective such that they think they understand it and no one else could study it, not even most heretics. [Answer] One very fundamental assumption in scientific inquiry is this: the rules stay consistent. This is what allows us to make testable predictions and hence run experiments to determine how well our theories match 'reality'. Without this ongoing consistency, the scientific method cannot function. The key to distinguishing magic from science, then, is to make the rules variable. In fact, if you describe magic as the action of pure, unfettered intention, the ability to make choices outside the framework of determined rules, then magic is literally the ability to either bend or break the rules. Of course, truly unbounded magic is not especially interesting, as, in the extreme, it essentially leads to omnipotence, at which point any meaningful story is impossible, for there is no more possibility for conflict. The tension, then, is between the raw potential of unhindered magic, as an expression of pure, unrestrained will and what limited actions us human magic-users can accomplish within the frameworks of our minds that strive to categorize and tame the world around us. In a sense, the science that defines our predictable world is the very mindset that limits our access to magic. The art of magic and the challenge of the magician, then, is to harness will and bend the rules within this framework of reality, without getting swept away by the raw power and losing all trace of human identity in the process. This is the balance of the mage, whose grasp on reality is always tenuous at best, for when the world bends to your will, you run the risk of getting twisted up in it. [Answer] [**Arcanum**: Of Steamworks and Magick Obscura](http://en.wikipedia.org/wiki/Arcanum:_Of_Steamworks_and_Magick_Obscura) -Troika Games In the land of Arcanum, technology and magic unwillingly co-exist. High level mages are not allowed on the steam train because it might blow up. High level techies cannot safely disapparate and most spells will fail on them. Tool use or spells will critically fail when done by a novice. Great mages fail at setting mouse traps and scientists fail the casting of the simplest spells. The higher the skill level involved, the greater the consequences are when the two meet. In close proximity of its 'opposite', failure is all but assured; epic battles would destroy everything or their spells would just fizzle and their circuits be burnt. -*He says he doesn't like you...* You can play the middle ground but none of your work will ever be of much notice. Scientifically trying to study magic would get you killed. Using magic to understand technology would not work (also not advisable). --- The best literature never reveals how magic works. If it does, it immediately removes my suspension of disbelief, as I know enough about the real world that *that ain't right*. [Raistlin Majere](http://www.imdb.com/title/tt0825245/quotes), on the differences of clerics and mages: (and the best description I've ever heard of how magic works) > > She's channeling the power of a god, you dolt. I'm wresting arcane energies from the very fabric of the universe - it's completely different. > > > [Answer] # Escaping scientific method To study something in a scientific way it's necessary to put it into a controlled environment, or at least (and in that case you need a lot of luck and Occam's razor) to have independent observers who can inspect it on a regular basis and take notes. What can go wrong? ## one-way interaction *no manipulation ⇒ no controlled experiment* Actually many things in modern science are observable but not accessible for manipulation and/or can't be put into a controlled environment (e.g. in astrophysics or in social sciences). In such cases it's difficult to make conclusions about causality or decompose a problem. We still can get an idea of what happens if we find something similar but more accessible to the inquiry, but if the nature of magic is alien enough it won't be possible. **Examples.** Things like Clarke's monoliths if you explicitly label them as magical or an xxx-dimensional lovecraftian creature that perceives our universe as still images on a thin film. Both can imbue people and things with supernatural properties. **Limitations.** Magic is supposed to be something that characters are able to utilise. So at most the source of magic may remain enigmatic but the artefacts produced by it still are subject to scientific research. ## subjectivity *no independent observers* Inability to separate subject from its observer may also help, but only if it cannot be circumvented by some kind of indirect manipulation/observation. Consider dreams as a real-life example. Granted they were studied by Freud, but his methods have been discredited since then and afaik nowadays there is no rigorous way to analyse dreams. **Examples:** * a world where psyche... magical substances or spiritual practices *actually* get useful by greatly enhancing interpersonal interactions but hinder rational thinking (does love count as magic?); * 'kafkaesque', 'solipsistic' or 'totalitarian' worlds where evidence has a tendency to disappear behind your back. **Limitations.** Again, it may be hard to study these kinds of magic directly but one can investigate its secondary effects. ## incomprehensibility *no regularity* Suppose the magic is projected by some kind of non-human sentient beings. Studying human behaviour is difficult enough since humans claim to have free will which translates to "I can mess up your experimental results just for the sake of it" and comes from the ability to reflect on the fact they are being observed and on their own past behaviour. But imagine the said creatures being vastly more intelligent than humans and/or — like the WoD fairies — able to tap into the collective unconscious so they can always subvert our expectations. **Example.** Gibson effectively did it in the Sprawl trilogy, even calling them 'loa'. **Limitations.** The only obvious issue with this scenario is that it looks more like human being an instrument of magic, not vice versa. # Sources of inspiration *Humanities* are a field of knowledge where interesting questions can be posed but attempts at scientifically rigorous answers often fail. So they may be (and often are) used as a model for how people in a fictional world perceive and study magic (not every study necessarily is scientific). [Answer] > > How to keep magic separate from science? > > > "Science" includes many fields of study. How to make it such that magic is not one of them? How to make magic resistant to study by experimentation? > > > **Keep the "hidden" effects of magic measurable only by magic.** For example: Where does the energy for the magic come from? How is it conveyed from the source to the target? A magician could answer these questions, based on direct observation/perception. Yet, to any non-practitioner there is no evidence besides the end effect. **It will be a necessity of the practitioners to make formal studies of their craft.** It's how they better themselves and share their knowledge. The very nature of a *spell* implies that a magical force has been understood enough to be captured by a repeatable ritual. However, explaining this to anyone that isn't a practitioner doesn't amount to much. They can see something happening, but that have only the practitioner's word on *how* it happens. > > Science must be "logical" and "rational" and magic not. A person with a rational mindset should not look to magic as the first answer. Why? > > > **Human magic should be limited to a small number of uses, but *presumed* to be capable of more.** Perhaps the magic can only be used to produce scientifically impossible physical effects: levitation, teleportation, spontaneous energy/heat/light, etc. Superstition would then have people believe magic can: bend your will, make you sick, cure you disease, etc. Why? Because that's how people work in the real world. Superstitions abound in every part of Earth. Demons, bad spirits, witches, angels, gods, ancestral spirits, have all been credited in ways that a rational, educated mind would not. **The field of human magic should be full of disagreement.** Perhaps they disagree on the origin of their magical powers, or methods. Maybe multiple methods exist to execute the same effect. The lack of consistency will make it even more difficult for scientific scrutiny. Imagine there are 10 known spells that do the same thing (let's say lift a boulder), and that it's *truly random* which spells and how many will work for a given mage. Then add to it that even mages casting the "same" spell will have slight variations based on personal style, and it's a quantification nightmare. > > And how and why would the scientific method ever have developed if a major part of reality was resistant to it? > > > **Science can still classify phenomena and experiment upon magic, but can't reproduce it.** For instance, there's no reason science wouldn't try to figure out *how* a massive, wingless dragon can fly. But eventually, they're only going to be able to record observations. Science would have no way of explaining the hows and the whys, and wouldn't be able to develop applications for their knowledge. > > I left the nature of magic open because that's an inseparable part of the question. What type of magic could fit this world? Is there any magic system that can make sense here? > > > **I think a magic system that is based primarily on violating the physical sciences would work very well.** Lift things up, pull things down, fly, transmute, teleport, areas of silence, casting light or darkness, invisibility, and pretty much anything a Bender can do in Avatar/Korra in regards to elemental manipulation. The magic should generally not be able to affect biological or psychological processes (at least not any more often than necessary to seemingly validate superstitions). This precludes increased longevity, healing, cursing, mind control, etc. The "strength" of magic should be, to the outside observer, entirely random. Some purely fictional quality or qualities should be responsible for magical ability. "Spirit", if you will. There should be no correlation between race, body type, size, physical strength/speed, general appearance, intelligence, personality, family/genetics, etc. and the strength of Spirit. You can take this further, and have the number of mages *also* be random, not dependent on population size or geographic location. There could be no correlation between the number of mages from one generation to the next. Even creatures that exhibit magical abilities can have randomness applied. Let's use the wingless dragons as an example again. Their max speed, maneuverability, acceleration, max flight height, etc. should have no correlation with their size, weight, number of spikes, color, age, etc. There are any other number of stipulations you could put into place, that would make magic less appealing than science for explanations. A remote tribe could have a very unusual power, but they can only demonstrate that power in their tiny geographical area. There could be some areas/creatures that actively interfere with some technologies (or even electricity), that make it harder or impossible to take measurements. Certain elements or objects could be immune to magic for no apparent or explainable reason. In the end, science would need only be aware that magic exists, is evidently controlled in some way by certain animals and humans, and that it can do things science can't explain. But, by its nature, magic would be unpredictable when trying to achieve consistent results. **Relying on magic may work in the short term if the resources are available, but it'd be up to science to make the real achievements.** Personally, I think such magic would also spur science, as it would try to "compete" with magic. So, your village has a guy that can start fires by snapping his fingers? Well, our village invented matches and now *all of us* can start fires whenever we want. So, this 100-pound man can lift a 5,000 lb boulder with a wave of his hand? Well, this machine can lift 20,000 lbs with the push of a button, and we can build *as many machines* as we want. So, you've figured out a way to train a certain dragon breed for riding? Well, we invented the airplane and we don't need animals to fly. And so on. [Answer] A lot of people are saying that you shouldn't try to make magic and science separate, that it's not possible, so long as there are visible effects. But there's actually a simple way to keep them separate. Connect magic to something that we already know can't be studied: **individual consciousness**. There are two ways to do this that come to mind. **Approach 1:** Humans have no magical abilities, but magic comes from spirits/gods/capital-G God. The being(s) that control magic are either a) unpredictable and capricious, or b) go out of their way to avoid being studied and reduced to a formula. Either way, humans can only invoke magic by calling on these being(s), and, even though the effects may be *observable*, scientific study would not be able to find meaningful *patterns* in them. **Approach 2:** Magic is completely individualized. One's personality and experiences determine one's magical abilities, but in a deep, complex way that isn't based on any observable patterns in brain chemistry. Even though a particular individual's magic may be analyzable, if that person's self-image changes in some drastic way, their powers may change accordingly. Both of these would make for an interesting fantasy setting. Approach 1 would make magic look a lot like religion, and some scientists would likely scoff at it--even if the effects were plainly observable--because they wouldn't appreciate outside forces meddling in an otherwise orderly world. Approach 2 would probably result in scientists being desperate to understand magic, which could even be a plot point in itself. Either way, although magic could, in theory, do *anything*, its effects would likely be random enough, and perhaps rare enough, that it wouldn't be the first explanation someone jumps to when they see some new technology or phenomenon. [Answer] > > And how and why would the scientific method ever have developed if a > major part of reality was resistant to it? > > > You don't need to make Magic resistant to scientific study, just make it really complex. The scientific method *did* develop in our world, starting from a point when everything *was* magical. Why do we have astrophysics today, when it was once clear that the sun was carried across the sky in a chariot of the gods every day? It's because some things were predictable and rational, and we discovered we could not only make theories about them, but test those predictions. If most things in your world are rational, then people will make a science of studying them, even if they find exceptions to the rules. Limits in the theories is what leaves room for "Magic". Back to astrophysics: We observe galaxies being pushed apart. We add up all the forces we understand, and find we need one more to make the math work. So we just say "Dark Energy". That's just another name for magic that we can observe, measure, but not really understand. > > Science must be "logical" and "rational" and magic not. A person with a rational mindset should not look to magic as the first answer. Why? > > > Because it is hard and not needed most of the time. Why don't you think of special relativity whenever you see an object in motion? Because Newtonian physics has enough predictive power and much simpler math. And perhaps because Magic doesn't play nicely with the rest of Science. Think Quantum Mechanics. The rest of Science deals with concrete objects with defined position, mass, velocity. QM has superposition of states, matter waves, and collapse of probability wavefunctions, stuff that just doesn't work like the majority of things you encounter everyday. Scientists know of it, and they know it can be described by complex mathematical equations, but it's just not relevant or needed to do their work. So how to explain > > human magicians who cast spells, whole species that are magical in nature, locations and objects with persistent magical properties...? > > > Just as we have super-tasters and people who are not red-green color blind, magic users and creatures may be able to perceive the fringes of the forces of magic. They can see the Quantum-Magical probability waves, and pull on them. But it takes lots of practice. And the math of it hard. Super hard. Only a select few wizards can really solve the equations needed to develop new spells - to predict that this incantation will have that effect. It takes extreme control to channel the forces of Magic to "enchant" an artifact so that it displays QM behavior on the visible scale. Most people will use science-based technology over magic simply because it is easer to use and understand. Just like in our world. If I was gifted with great hand-eye coordination, and I practiced really really hard, I might also be able to do magic like Penn & Teller. But it's just much easier to walk across the room than to teleport. Compare this to the way crossbows replaced bows, and early firearms replaced both, not because they were better but because they were easier to use, and needed less skill to get an acceptable result. [Answer] I can think of 2 methods to make a magic system highly resistant to scientific inquiry. Option 1: Base it on the whims of a conscious, highly intelligent, almost omnipotent trickster god who can see the intents of all involved and takes personal issue with anyone attempting to subject his gifts to systematic/rational analysis and actively thwarts their efforts so that the closest anyone can get to serious understanding is that as soon as anyone starts even thinking about trying to understand it in the "wrong" way everything either stops working entirely or the magic gets malicious and turns on anyone trying to measure, quantify or analyse it. Option 2: Not totally immune to analysis, everyone is trying and it's useful but hard to predict. This is the softer option. Make it anti-inductive like the stock market. However magic works it's linked to the ways that humans use it and the ways that humans think about it. A practitioner is free to subject it to scientific analysis and may even make significant gains, their power waxes as they plumb the secrets of magic and their apprentices gain power from the same secrets.... and then it all starts to not work. The flows of power adjust to the new "market pressures" as many people attempt to tap the flows of power and suddenly the rules and even meta rules have changed dramatically and unpredictably. In the old days it was possible to work out the rules that would remain stable for generations, years or months at a time but since the world has gone through a kind of magical industrial revolution things are just too fast as millions of people try to draw the available threads of power from the multidimensional knots they both make it more complex and drive faster change while the minds and dreams of humans themselves help create more and more complex mechanics. [Answer] I'm going to focus on the aspect that you want rational personal people to conclude that magic isn't the reason for things. There is actually a really easy way to do this: make magic *rare* or *subtle*. For example, suppose you are a rational person at a casino, and you watch a guy wave a wand and then win a single number bet at the roulette table. You are going to assume there is no magic involved, because it's not very unlikely a person will win a single number bet, but it is very unlikely that a wand waving person is actually a wizard rather than a fraud or a showman or someone just having fun. And when the person wins ten times in a row, you're still going to assume there is no magic involved because sophisticated crooks and promotional events are far more prevalent in your world than wizards are. Similarly, there are more circus acts going around with horses with horns glued on them than there are actual unicorns in the world. There are more tourist traps than truly magical sites. There are more clever toys you can make out of magnets than you can with magic. Even if magic is common, you can still get this effect if your world has large numbers of frauds. In such an environment, when faced with magic, rational people will not take it at face value, simply because it's so unlikely things are what they seem. Naturally, genuine rational inquiry will probably uncover the truth rather quickly depending on the particulars. Although your purposes may be served by the fact that there are plenty of "rational" people who are really just mimicking what they believe rational people believe, and they will continue to deny magic, even in the face of sufficient evidence it's really involved. [Answer] By far, the most straightforward solution would is to make your magic *un-science-able*. Since science is simply the study of natural phenomenon, you must make magic impossible to study, or people will do so. Conveniently, we have a very, very loose analog for such a thing in the real world- quantum particles. Despite the fact that it runs counter-intuitive to everything we observe and understand on a day-to-day basis, simply *observing* a particle changes that particle's state. **Option A:** Apply that same formula- magic exists, and its effects are predictable, such that a wizard knows his fireball spell will create a fireball and it will head in the desired direction. However, if you attempt to study or directly observe any individual aspect of the casting, the spell fails. This, being a fundamental aspect of the universe, cannot be circumvented by logic- no amount of distance, abstraction, or ruse can "trick" the magic. It somehow, despite all logic suggesting such a thing to be impossible, *knows* that it is being studied, and therefore will not work. Science will study magic to the furthest extent possible, reaching the scientific conclusion that magic cannot be directly studied or observed. Science will then move on to studying the *effects* of magic, IE, how much damage does a fireball cause, rather than the magic itself- much as the study of responding to tornado damage is separate, though connected to, the study of tornadoes. **Option B:** To steal a page from the SCP Foundation wiki, magic is un-studyable for memetic reasons. Any observation you make of how magic functions, you'll forget. Any notes you write down, you won't be able to read. Any footage you take, you won't understand- or you'll forgot what you saw as soon as you look away. The only aspect of magic that scientists are able to remember and retain is this memetic principle- the world can remember that it's impossible to study magic, but it forgets anything deeper. [Answer] > > It should allow human magicians who cast spells, whole species that > are magical in nature, locations and objects with persistent magical > properties. > > > As others have noted, this is impossible to do - anything this conspicuous would be examined by, and become, science. However, it could be that magic is more subtle - it can achieve a lot, but it's always explicable by some normal explanation, and even for the practitioners it's more a matter of faith that the ritual or w/e they performed resulted in the outcome. . . like a lottery win or a road accident etc. Science would therefore always find a more prosaic explanation, and find nothing to study. [Answer] ### How they can be both not science and predictable **Something just can exist and cannot be studied.** Consider if our world is *in* something like a black hole, we can still study things outside because we know the only ways things can be formed naturally. But if they are all sent deliberately by some intelligent species, and if they want, we will probably completely lose ideas, and still may found some of them useful. Otherwise they can state explicitly what they are, but that is still not science. So if people know how to use magic just because they are told by someone (god, inner spirit, ancient unique artifact, coexisting species who didn't develop science yet and aren't cooperative, or even a talented scientist who calls something "magic" themselves and refuses to tell the details, etc), and those who tells the magic can change the rules of magic and even lie about them, and they decided that scientific ways are bad, then it would not be science. Intelligence is one way to make [simpler things very unlikely to be better](http://en.wikipedia.org/wiki/Occam%27s_razor). There may be other ways. The same applies if people can request someone doing so, but have no way to force them to do physically. Or we can just allow people to build things where people can never know its inner structure physically again, and then forget those technologies to build them. If people just did build some weird mechanisms into it, it can be less likely to be studied well than natural things. ### How they cannot be studied After people have some ways to know them at the beginning, the other part is easy. But it might be boring to explain them in stories. There are [uncomputable things](http://en.wikipedia.org/wiki/Computability). Just make the magic mechanism behave like some of them. If casting a spell is just like writing a story with ideas which are neither boring nor previously known (the above part can explain why this can affect the result), science can define it but probably can't help improving it too much (without making things boring or known). Or easier: the computation requires a real number, and those who can manipulate real numbers can lie and are separate from our world. But if there are other things related to magic which don't involve these (such as these are only required when someone's casting a spell, but not when someone's storing/collecting the magic materials), and are using tools those aren't intelligent, those mechanisms can probably still be studied. There are other possibilities including: * It is just too complicated to study. * There are some exotic rules like if they are studied, they will be gone, but everyone has their own magic so they won't affect each other. * It is just already too obvious that it doesn't worth any study. * People don't want to share their knowledge for some reasons. * It is based on some [records of infinite length](http://en.wikipedia.org/wiki/Oracle_machine) and people cannot copy them. The organization controlling them refuses to study for some reasons. * It just has some rules like "the shortest and lexicographically first unprovable proposition is always correct", and we will never know it without being told by someone accessible to some proving methods unavailable in our world. * Different magics can never be used together. And magic can only work if it is now in a situation in the common sense. Any non-obvious things never become useful. ### For simplicity If our emotions (which also have magical powers which can not be produced artificially in the setting) are not only sometimes not easy to control, but also always *deliberately* lies to our rational thinking, and studying them physically always break them immediately, then there are not many things that science can do. And those cannot be studied are likely always more intelligent or strong if you are using the above excuse. ### What cannot be avoided If everyone knows magic plays important roles to life, there must be someone studying things related to magic. Say, the economics related to the existence of magic. I don't see a way to prevent that. If there is a way, it is probably making the science in this setting too weird. (Nobody cares whether they are considered science or not, though.) People can still identify them in science. Such as the mass and energy conservation only holds if not involved some magic. Or it always holds, but all the magical materials contain unknown amount of energy (and no relativity here). People can still believe how they are correct like gamblers. [Answer] If you want magic that can't be properly studied and analyzed like science, but also can't be so completely chaotic that it's not able to produce reproducible results (wizardry, etc,) then have you considered an [invisible Flying Spaghetti Monster](http://en.wikipedia.org/wiki/Flying_Spaghetti_Monster)? Magic is real, and is reasonably consistent, because that's the way that The Being That Takes Care Of Magic (TBTTCOM for brevity) wants it to be. But every once in a while, some scholar gets a little too big for his britches, trying to not only probe into *what* magic does, but *why*. And TBTTCOM doesn't like that, so TBTTCOM subtly shifts and twists things around until they either just sorta fail, or blow up in the scholar's face. Sometimes literally. Or sometimes even worse than that; did you ever wonder where some of the creepier mythical curses come from? It's happened enough times throughout the ages that scientific experimentation into the fundamental principles of magic has become the stuff of cautionary tales. Which, of course, doesn't stop people from occasionally trying. Generally they come in two varieties: naive, idealistic and inexperienced young wizards who don't know any better, or great and powerful archmages who *think* they do know better, who have studied the mistakes of the past and know how to avoid making them... not that that matters to TBTTCOM; they'll just make some *new* mistake this time instead! [Answer] This question has attracted many replies, but few answers. I’ll make a stab at the latter. Let’s be clear on the question: **Given:** * Something that roughly resembles typical genre-fantasy magic * An Earth-like world and history, no earlier than the late nineteenth century * Institutional science, recognizable to us as such * Science does not study magic **Implicit:** * Science does not study magic because it doesn’t succeed * Science does not succeed because something about magic is resistant to scientific investigation * Scientists do not as a rule find this resistance interesting enough to investigate on its own **Questions:** 1. How can this be possible? 2. How would the magic work? To summarize, the majority of answers are of the form, “If it’s real, it can be studied by science.” These answers are non-answers, as they disregard the givens of the question. **Proposal:** Thorsten S. made an excellent point, having to do with the number and nature of factors or variables. In essence, if there are too many factors, and the factors themselves vanish or alter as soon as they are perceived, experimentation is likely to fail. This got a lot of nasty answers, but Thorsten was quite right. We can think about this in two ways. **First,** we might simply suppose that a magical phenomenon is a dual-ended chaotic system. As Edward Lorenz put it, “the present determines the future, but the approximate present does not approximately determine the future.” So let’s define our spell as follows: ``` P1 → F1 P2 → F2 Spell mana Effect ``` In other words, there is a determinate connection between the spell and the obscure, postulated power that will in turn generate the actual effect, again deterministically. Unfortunately, each spell’s performance depends on a range of variables, and when very small changes are made they produce wildly variable results. Since each magician must to a great extent find his own way of manipulating mana, this means that two magicians can produce very much the same results without their methods apparently overlapping much at all. **Second,** we can invert the problem by lodging magic beyond the outer limit of scientific knowledge. I don’t mean that it’s unknowable, only that, as several distinguished anthropologists have argued, magic postulates unlimited determinism. The classic example comes from Evans-Pritchard’s study of Zande witchcraft and sorcery. To simplify, here we have Uncle Herman, sitting having a snooze beside the old granary. A high wind comes up, the granary falls over, and Herman dies. Explain. * Scientist: wind, dry-rot, etc. * Magician: wind, dry-rot, etc. – and witchcraft What’s the difference? The scientist has not in fact “explained.” He has assumed that, in the absence of definite evidence to the contrary, there is no determinate connection between the forces that caused the granary to fall and the fact that Uncle Herman happened to be sleeping where he was. But that is an assumption, based on a complex system of logical investigation, accepted practice, and so forth. The magician, however, refuses to accept this. He lives in a purely clockwork universe, as it were. It is simply not possible that there is no determinate cause of Herman’s death. “Random” means nothing—it’s a dodge to avoid having to explain anything. **Result** If we accept that both aspects of the proposal are valid, then we have a field in which scientific investigation is essentially pointless. On the one hand, experimentation doesn’t work well, because you can’t isolate the variables. To investigate fire spells, for instance, you can either study how Magical Mandy does them, which is at least consistent, or else study how lots of magicians do them, which has statistical value. Unfortunately, the first study is statistically meaningless, because you can’t compare to any other cases, while the second produces completely inconsistent results (two magicians use paint, the other 98 don’t; two different magicians yell words that have Z’s in them, the other 98 don’t; and so forth). On the other hand, these magicians seem to infer and manipulate causal mechanisms that simply aren’t there. The diviner, let’s say, can with 100% accuracy tell you what’s on the back of a card or whatever, and double-blind tests confirm this. So what do you learn? Nothing, because he says it’s obvious that this card is the Queen of Hearts because of the pattern he saw in his breakfast cereal this morning, and so far as anyone can tell, he’s telling the truth as he sees it. To him, the world is tied up with all kinds of weird forces, and he can “prove” their reality through this kind of divination, but they don’t respond to any other kinds of tests. They’re just not there. So when you do big statistical studies, the odd magician will stick out like a sore thumb, because normal probability just doesn’t work the same for him. Ultimately, nobody in the science business is going to waste time and money on this nonsense. It’s real, sure, but it doesn’t mean anything. There’s nothing to be learned from it. You can’t build anything with it. If you involve real magicians in any kind of testing, stuff goes haywire, causing damage and expense. So let’s just ignore them. Yes, *in theory* you could study these effects, but what for? What sort of nut is going to waste his life trying to figure out why Magical Mandy sucks cough-drops after casting spells? And for sure, nobody’s going to fund his experiments. **Q.E.D.** [Answer] Well, I can see an easy way to keep the two alive. Magic sucks. It allows individuals to do great feats, but it's not really worth the cost. E.g. it takes way too much study, it only applies to a random bunch of individuals (say, it depends on some genetic marker, or maybe there's two species living on the same planet - one has it, the other doesn't). Scientific engineering, on the other hand, is available to everyone with the push of a button. Only the initial investment is costly, once you know how, you can make thousands of the machines and quickly outperform any wizard. Even if there's wizards with more power than any machine, they cannot be duplicated - building the same machine 1000x just takes some amount of work; having 1000 wizards means 1000 lifetimes sacrificed to study and practice. Basically, wizards are crazy. They sacrifice an absurd amount of work just for a measure of individual power - but there's no way they'll be able to use that power to e.g. rule the world - while there's no single person who can challenge the power, there's no way they'll be able to fight the whole kingdom. The reason most people don't even bother studying magic is that it simply isn't worth it. Way too much work, way too little gain. It becomes a lot less attractive when anyone *can* learn it - Harry Potter feels exclusive because he's one of a fraction of humans who can ever practice magic; if it was just another skill that anyone can learn, like reasoning or math, it loses a lot of its "I AM THE MASTER OF THE UNIVERSE!" appeal. When you yearn for magic powers, you don't usually care about the power itself - rather, it's about having the power while others *can't*. Why isn't rationalist thinking considered a superpower in our universe? Now, eventually, science will enable mass-production of magic artefacts and magical machines and whatever. We're not there yet, and we have no idea when that will happen. Maybe the source of magic is a machine on itself, and we just have to stumble upon it at random (detecting power coming from somewhere while observing wizards with sensitive instruments?). Maybe we'll be able to reproduce the genetic marker, or the complex machinery required to cast magic, and maybe we'll be able to make studying magic a lot less work, taking a lot less practice (e.g. the equivallent of steroids for magic-muscles). But we're not there yet. Until that happens, magic will have its place separate from the non-magical populace. [Answer] Just make it so that science hasn't *yet* figured it out. You're stuck otherwise; anything that's real is 100% compatible with the scientific rational process and there is no way around it. But there is no reason why magic can't just be something that science has figured out yet. You could have lots of scientists struggling but failing to figure it out. It would be the same as how rationally-minded people struggled with chemistry 1000 years ago – despite a) being quite able to do some chemistry, and b) lots of "magic level" chemistry happening within the human body, quite observable but totally incomprehensible at the time. [Answer] You could say that magic needs a certain state of mind to work. It's practitioners could have to rely very much on intuition. That state of mind could be incompatible with doing scientific investigation. [Answer] I had exactly this same problem for my setting, and the solution was twofold. 1. Split the world, having magic in one half of the world, and in the other half of the world, have science. The split in the world is in a fourth dimension, making physical travel from one side to the other difficult. The two philosophies are incompatible in their most advanced states. 2. Magic allows for effects that cannot be produced by science (yet?), but magic comes at a cost that limits its use and making it expensive. [Answer] So many paragraphs on this page... I will put it simply: > > To keep magic separate from science, it simply shouldn't be rationally explained. > > > * Do this ritual/process/incantation, and that result happens. *Why?* It's magic. * People have magical abilities. *Yeah but, how would a person generate and control fire?* Magic. > > Science is much more dependable and explainable, so unless there happens to be a specific magical answer for a problem, people would have to figure it out using science. > > > [Answer] One simple way to keep magic from being "understood/complete" like another scientific field would be if the effects were repeatable, but side effect were unpredictable. For example one day you heal a person's leg and a chicken in the yard dies. Next day you heal a person's leg, and an apple tree in the next village turns into a cherry tree. On the third time you heal someone's leg a haunting melody plays. Etc. Similarly magic could have "bad dJinni" effects. Healing the person's leg and they take the more dangerous route and get robbed. ]

[Question] [ I'm currently writing up a world where every thing and concept imaginable is represented by an immortal Being/God. Assuming Gods don't grant powers to their worshipers, but may interact with them; why would people devote themselves around a clearly malevolent God of Murder? What would cause organized worship of said malevolent God? Besides being deranged in the head. Overpopulation? [Answer] # What is the difference between a god of murder and a god of war? Is it scale, or just semantics\*? You could say that one is the god of murder and the other is the god of mass murder. Murder has very negative connotations, but war, war is glorious. Your god of murder needs an image change, something to make the concept more acceptable. Perhaps he's the god of assassins, though this is probably a side line of the god of death. The sailors get a lot of gods of the sea, the sea is a very dangerous place to be. There are also gods of fertility and farming for the more landbound peasantry. There are gods of just about every trade and assassination is as dangerous a trade as any. There are endless gods of death, everybody has one (or more), after all, everybody dies. It's just a matter of encouraging said god to take the person sooner rather than later. Maybe a god of vengeance, [Adrestia](https://en.wikipedia.org/wiki/Adrestia) (also known as [Nemesis](https://en.wikipedia.org/wiki/Nemesis_(mythology))) was known to accompany her father [Ares](https://en.wikipedia.org/wiki/Ares) to war. Remember that Ares was himself the god of bloody violence in war: > > "overwhelming, insatiable in battle, destructive, and man-slaughtering." His sons Phobos (Fear) and Deimos (Terror) and his lover, or sister, Enyo (Discord) accompanied him on his war chariot. > > > Athena was the goddess of the just, controlled, tactical war. Politicians might call on Athena when sending the army to war, but the soldiers know that on the field they'll find only Ares. Place your offerings as appropriate and pray that he's on your side. Perhaps this is a side role of the god of justice, execution is after all a standard acceptable method of punishment in most religions. Though perhaps you want [Adikia](https://en.wikipedia.org/wiki/Adikia) the goddess of *injustice* to aid you, because you know you're in the wrong but you still want to be rid of your rival. \*It's semantics, a legal technicality. The difference between judicial execution and a revenge killing is the judicial part, the bit where society approves the action. War could be said to be government sanctioned mass murder. It's just point of view. --- This could also go the other way, the negative connotations of murder used against a god. # He wasn't always a god of murder The problem is that society has turned against this old god and the old traditions. Some new god has come along and now society disapproves of the occasional human sacrifice the old god demanded. Some stand by the old ways and make the sacrifices, but they're considered to worship the god of murder, not by themselves, unless they've taken it as a badge of pride, but by others. Though like [the Thuggee](https://en.wikipedia.org/wiki/Thuggee) they're likely to be cracked down on by the new order if they sacrifice too many people. > > Estimates of the total number of victims vary widely, since no reliable source confirms the length of the Thugs' existence. According to the Guinness Book of Records, the Thuggee cult was responsible for approximately two million deaths; British historian Mike Dash said that they killed a total of 50,000 people over an estimated 150 years. Political scientist David C. Rapoport estimated that 500,000 people were killed by the Thugs, making them the most destructive terrorist group in history.[9] According to other estimates, they murdered one million people.[10] > > > Whether it's human sacrifice, gladiators (to the death), duelling (to the death of course) or trial by combat (need I say it?), a god who encouraged/demanded these things could become known by outsiders as a god of murder. This is classic us and them propaganda. * Our great god who loves and protects us, your god of murder who loves human sacrifice. * Our great god of war who aids us in our glorious battles, your savage god of bloody murder who loves nothing more than a field of corpses and keeps you in a constant state of war. Which way the god falls in this depends on where you stand. Though perhaps like Ares and others, the god is both aid and terror even to their own side. On the other hand > > Some men just want to watch the world burn > > > [Answer] 1. Because they are murderers and want the god of murder to bless their efforts or do their bidding. 2. Because they want to appease the god of murder, in order to avoid being murdered themselves. [Answer] The reasons might be as numerous as the reasons for murder itself. A well known fantasy example: There was an orphan boy in the world of Skyrim, who prayed to the Night Mother to send an assasin to kill the owner of the orphanage he ran away from, because the owner (known ironically as "Grelod the Kind") treated her children very badly. Some hypothetical examples: * A cheated woman prays to the God of Murder to take revenge on her Ex-husband or his new love. * Some political extremists pray to the God of Murder to kill a political leader because of his political views. And so on. > > What would cause organized worship of said malevolent God? > > > Because the more people pray to him / her, the more powerful the deity gets. [Answer] Because its devotees have some measure of protection from random murder. Won't help with targeted hate, but an xx% reduced risk of being mugged and murdered is probably worth 5 minutes of worship? [Answer] Why should the murdergod be malicious? There are a few situations where it makes perfect sense to truck with the faith and clergy of St. Stabs-a-lot. # Policing their own Think of Discworld and the various Guilds. Nobody *wants* to be murdered, but if the state was too weak to police its criminals, you'd at least want a check on them. The clergy of the Murder God do not take kindly to *unsanctioned* murderers, and their own members must obtain a blessing for every kill, train to slay quickly and cleanly, and obey a strict quota. # Every part of the buffalo In a society where resources are scarce, cannibalism is common. Murderers could serve as butchers of humans, culling the old and weak, and putting their blood, flesh, and bone to good use. Nobody wants to be the guy that tells grandpapa "Sorry, you're too old to work and someone else needs the food you're eating" but if there's a dedicated murder guy with that job, it's a little less awkward. # Death with dignity The incurably ill frequently seek a quick death, and followers of the murder god are just the people to give them one. You could even get a choice - poison and a painless death, or glorious death in battle against a murder Champion. And the justice system could also use this murder clergy as a source of remorseless executioners. # Blood sport This can take either the form of straight-up gladiatorial combat, or the most exciting game of Assassin ever. Trained killers stalk each other in the night, and in the morning the press reports on the scores. People who lust for blood can sign up and work out their issues without threatening innocents. [Answer] Lets look at mythological figures in our own which which have attracted worshipers. We've got figures like Shiva, entites of destruction and change, we've got various gods of war. **Balance** In most cases you find that the religion talks about some kind of balance, destruction allowing change, war ending tyranny, death ending pain. Murder is normally bad but we could imagine worshipers who talk about when it's necessary. **Killing Tyrants** Murder is a specific type of homicide that is distinct from things like soldiers killing each other on the battlefield or criminals being executed within the law so this cult, these worshipers are going to be inherently about being outside the law. But that doesn't mean they have to be entirely evil. They could be a particularly ruthless vigilante organization. Less evil followers could hold that when a monster can't be touched within the law, when an emperor takes power and tortures his subjects for fun, when the mad senator tries to drag a state into war for his own ends, when a mob boss can't be touched because on paper he's only linked to his legitimate businesses, when those staying within the law are powerless to act... there can be a time for murder. **Assassins** As another answer suggests, there's also the "dark brotherhood" option with an organization of assassins who answer prayers to the god of murder... for a price. Indeed both could exist as opposing organizations worshiping the same god. [Answer] Consider an Olympic athlete. The public might look at one of them and say, "She is a great runner." But her family knows she is also a great accountant, a wonderful sibling, etc. Most people are more than our jobs. Why not gods? Maybe there are simply gods. They have power, and they manage things. At any given moment, they manage some specific thing, and maybe they get known for managing it really well. So the God of Murder has a good reputation for inspiring particularly novel ways of killing... making her an idol for mystery writers. The God of Murder has to know about poisons, making her an ally of botanists and pharmacists. The God of Murder can instantly see the hole in any body guard setup, making her a friend and sometime drinking buddy of tacticians. "Yes, I manage all the serial killers. They generate a lot of headlines. But have you seen my garden?" One can imagine the scene between a mother and daughter: * Mother: "How can you start worshiping that monster that let your father be killed like that?!" * Daughter: "We got to talking at Dad's funeral. She apologized about Dad, but she needed a poetic justice killing to balance out the world supply of ironic death. I got quite engrossed in the accounting. Did you know Brazil actually has an irony surplus? It's quite dangerous. I'm thinking of becoming an irony monitor for the Murder Church when I finish my accounting degree." [Answer] Perhaps because it is the god of murder, and the people fear him because of that? Think of it like the gameseries [Black & White](https://en.wikipedia.org/wiki/Black_%26_White_(video_game)), where you play a god. you have the controll over your city and it's inhabitants. these people will worship you for two reasons: 1. you're a benevolent god and people love all the good you do. 2. you're an evil god and people worship you out of fear that you will sacrifice them for mana or kill them for sport. The same could be applied to your usiverse: this god of murder seeks out people and threatens to kill them or their loved ones if they won't worship him. [Answer] The Jivaro did this. I guess not literally, but effectively. They were the headhunters of Peru. They believed if you killed someone violently, their spirit would protect you. So they'd go off on a trip, murder someone, take the skin off his head, pour hot sand in it every night on the way home to shrink it and wear it as a protective totem. The fresher and scarier your tsanza (murder totem) the less likely it is that someone will mess with you. (duh) There's no room for peace in this belief system, there's no room for wisdom and knowledge, there's only murder and a short violent life. They were feared warriors, but they had no writing and their oral history was understandably short. This tradition might have been beneficial when constant raiding and invasion threatened (the people of this area successfully fought off Spanish rule) But there's no play for the long game. [Answer] ## It wouldn't without redefining murder Religions of evil never existed in reality: they were imagined to justify the persecution of foreigners. A god of murder only makes sense if the "murder" is morally or socially justified (not necessarily at the same time). For example: vigilante justice, mercy killing and warfare. ## Vigilantism Murdering tyrants and criminals that escape justice is technically murder even if motivated by a good cause. To be fair, it doesn't actually make you morally superior to the ones you kill unless you receive the community's approval. The entire point of capital punishment is that it is socially approved murder. ## Mercy killing Mercy killing, assisted suicide and so forth is morally tricky. Unless you have oracular powers that allow you to determine whether killing someone now will spare them a lifetime of suffering, it is morally reprehensible to take the lives of innocents. Furthermore, this opens the door for situations where killing an innocent person destined for a long and happy life will result in less suffering for more people overall due to the vagaries of fate. In which case the moral option is to murder the god of fate and replace them with a less sadistic and arbitrary god. ## Warfare Warfare is socially approved mass murder. Regardless of how it is justified, killing is still killing. [Answer] ## Perhaps your god is actually a god of scheming, plotting and mind-games? Planned murder requires motive, means and plan, finding the perpetrator requires deduction and meticulous search for clues, god of "murder" enjoys both. Break-ins and bank robberies have all the same elements, but since stakes are lower, god of "murder" prefers murder. He enjoys watching plots unfold, and favours those who can outsmart and outplay the other side. As such, he's a god of thieves, detectives, diplomats, spies, strategists, cardsharps and gamers. He doesn't like the last group, though, he finds their games bland, they lack substance and proper stakes. All in all, common people pray to him, begging to be spared from becoming back-story of another episode of his favourite police procedural. Criminals pray to for inspiration in scheming and luck in execution. Policemen pray to for acuity to find the clues and see through plots. [Answer] Murder is such a loaded term. Why not rebrand as # God of (Violent) Justice The reasons for worshipping said God could be an oppressed people wishing death upon their oppressors. [Answer] **Propitiation**. It was very common in the ancient world (for example, in Rome) to offer prayers to a god in hopes of dissuading them from causing harm. So you might have a state position as priest of the god of murder, where your job is to ensure that as little murder is committed as possible. (*Yes, 200 people were murdered, but if not for my ceaseless prayers it might have been 2000.*) This could also be done on a private level: a person might offer prayers to the god of murder when going through a dangerous area, lest (s)he be murdered, or make offerings to such god before leaving for a long, dangerous journey. **Cult worship**. Perhaps there is a god of murder but common people know little about him. Instead, there is a secret organization devoted to this god. Those who join learn a little about the god, learning more and more as they are initiated through levels of advancement. They might not know the true nature of their god until they are very highly placed in the cult. This model of worship was also very common in the Mediterranean world; examples include the cults of Mithras, Sol Invictus, Bacchus, Isis, IOM Dolichenus (a version of Jupiter/Zeus), and Magna Mater; the Eleusian Mysteries are another example. In fact, Christianity was considered a mystery religion in its early years. **Personal advancement**. Perhaps unscrupulous people worship the god of murder in hopes of killing their rivals (*Great god of murder, please kill my fellow nobleman Porcius who cursed my farm.*), or perhaps assassins pray for general murder-related skills. **Warfare**. Possibly the god isn't against a bit of wholesale slaughter now and then, or perhaps he can be persuaded to kill off enemy generals or kings. This could be a powerful political tool which could cause widespread organized worship (*We, the King, entreat all of you to worship Moloch, and to pray for the downfall of our enemies.*) [Answer] There are many maniacs out there... Some of them might "enjoy" seeing others suffer and therefore like the idea of a "God of Murder". They hope to see society plunge into darkness by everyone killing each other. Other than that: Maybe they want to distance themselves from other people. If everyone likes the "God of Love" I can make a "statement" by favoring the "God of Murder". [Answer] Consider the example of historical religions that relied on human sacrifice. To them, taking the life out of a human being was a sacred act, something very serious and meaningful that could be used to commune with the divine. Basically, that's how a devotee of the God of Murder would think. Murder is a special and frightening and horrid thing, and is feared by the rest of the population. Something like that is easy to become obsessed with, especially when there's an actual deity behind it. [Answer] If in your world, there existed a stronger version of our separation of church and state, then murders committed under the command of the God of Murder could not be punished by the legal system. It would be religious persecution to arrest a person for obeying their god. So, if you really, really hate someone... start worshiping the God of Murder and drop their name (wrapped in a healthy donation) in the collection plate each week. If your god favors you, you may see your enemy's name added to the list of martyrs (victims), and if you are truly blessed, you might be sent on a holy quest, to do the deed yourself. [Answer] It depends on society and function of God of Murder. To make it's worship appealing it would need to blend into your image of society and setting especially definition of murder. For possible options of original believers in supposedly stable society we have: * professional killers, like church of assasins (probably non-official if the law restricts the act of murder), other less religious groups would make it less formal and therefore they would be less organized. Everybody likes to feel protected and most of deities does not approve nor support killers, which leads to demand for professional God of Murder respected for it's prowess and probably their cult is illegal (it would supposedly need special circumstances to make it legit). * avengers, justice by law and justice for victims are completely different ideas. There are people who will seek revenge for suffering and tragedy that have fallen on their loved ones or themselves and they will need a God who will support them on their path of demons. This origin would create bitter image of God of Murder and most of people would keep an eye of believers for any face that they have harmed in the past. This niche is especially vague as includes potentially any cheated/swindled/ridiculed/abused/mistreated/tortured/loving/hating individual. * meek, those who are unable to stand against injustice and oppression will surely seek for help of deity which will act in their stead or push somebody to change the fate of their world. Cult that would originate from here would show God of Murder as unstoppable heroic deity that goes above the rules and brings the end to oppression, possibly swift justice. Probably it would end with God of Murder as close close associate (or even lover) of Justice. * afraid ones, people who feel scared of being murdered would probably like to be protected from worst by a proper deity which holds reign over all murder. This opens a path for protective image of God of Murder as the One Who Tames the Evil. This kind of cult would probably keep own more or less official army that would seek dangerous individuals (other than themselves) and make the world a tad bit better. * swearers, as it was said by Pratchett, in the end all swears are also prayers. If only deity is known for not reacting swiftly on such acts, the name of god of murder may be easily incorporated in showing both anger and hatred for somebody. To be strict it is more sign of cult existence than origin, but it may be that bunch of people decided that it would be profitable to restore once forgotten cult or respond on demand of society. * broken ones, god of murder may bring swift and painless death and thus relieve people of their misery. There are people who would wish for it, to end their pain or keep own dignity. This niche could originate from times of some terrible disease that maimed it's victims or nobles who are in general both rich and expected to keep their stainless image. * civilians on battlefront, in any warlike time there would be some people that may by bad luck stand against any soldier and have to kill them. Probably cult that would originate from that niche was created in more dangerous times and probably demands it's followers to worship god of murder by training killing moves and quick assessment of danger imposed by met individuals. * occasional killers, some people feel urge to make it supposedly once in their life-time without specific reason and need support of some deities. As origin they will probably make worship of God of Murder some shady business mostly common in world of criminals. * sensible-killers, in some cases (mostly scarce resources or danger imposed) it may be better for some people to die so the others may live. Then cult would be essential for survival of population and it may be kept as chapter of it's glorious past. It is all what comes to mind, however there are other possibilities for source of such a cult like: * social Darwinism, elimination of weak and ill ones. Believers are expected to keep themselves strong and healthy. * duelist/warlike society, murder of enemy in fight however perceived as illegal still is seen as honorable thing to do. Eventually would be welcomed in society of slaughters. * unusual definition of murder, as it was told already, maybe we are talking about society that do not call a murder just "unlawful killing". Potentially all executioners, soldiers, slaughters and even unlucky surgeons are just murderers and that only when we stretch definition of "murder". In some cultures (like Celtic) cutting down specific trees was considered murder which provides us more examples on possible variations of definition. * branching, God of Murder may be more bounded with other activities. It's just that he/she is not well perceived in some circles (which branded it as "God of Murder") or has some shady cell that "helps" other believers with their troubles. * decision of ruler, there are no specific reasons to make worship appealing to believers. It was just an order. * political/social, some of dignitaries started to worship a God of Murder. They tended to help other believers which made others join them to get special treatment. That is how have formed a political faction centered around the cult, which celebrations are occasion for believers to interact with each other in their circles. There are for sure many more other options but I'm unable to describe them all. [Answer] The one thing that's difficult to imagine is a god of *wanton* murder. When we hear the word "murder", we imagine carjacking, burglaries, senseless serial killings and mass murders, etc. A society based on glorifying random killings wouldn't last a year. The obvious alternative is to replace "god of murder" with "god of war", but that seems like dodging the question. I think there's a middle ground - a society that worships the act of killing a specific person, without also worship skill at martial arts, strategy, weaponry, warrior ethics, and all of the other concepts that come along for the ride when you worship a god of *war* rather than just murder. Murder is a *fascinating*, awe-inspiring concept. The fact that it's possible for one stream of consciousness to deliberately end another stream of consciousness is an important property of our universe, at least from our perspective. In some sense, murder is the basis of civil society, being a sort of counterbalance to free will. Anyone can get up in the morning and simply decide to cause problems for society. Laws are ultimately only meaningful because of the threat of violence. If you break the law, and continue to resist the police and the legal system for long enough, that path eventually ends with you being physically subjugated and dragged into a cell. Now, we don't consider it necessary to actually *kill* criminals, but you can imagine some martially-minded philosopher, maybe this society's equivalent of Confucious or Buddha, taking an extra step and deciding that until you *murder* the troublemaker, the arms race between physical violence and free will is incomplete, that it's always possible for them to find a way to resist you. You can deepen and embroider this basic philosophy as much as you like, but I imagine any society based on a worldview like this would have some of the following features: 1. A clear, maybe religiously based, distinction between wanton, anti-social murder, and justified murder. Perhaps the priesthood would have to consult God in order to determine when a killing is justified. 2. A justice system based squarely on the death penalty. 3. Codified, legal duels to the death to settle citizen's disputes. 4. Religious "sacrifice" of people like criminals and prisoners of war. Pretty grim, all in all. Maybe a society like this could only really flourish in a dangerous environment (lots of disease and/or war) in which there's a strong desire to codify and understand death, and more importantly, in which citizens don't have a more peaceful, non-violent alternative anyway. [Answer] Same reason people would worship an owl. To get an advantage. Make it a small group of people. Perhaps these are emperor or people who want to be monarchs. Perhaps this is an Aztec thing where the god **WILL** destroy you and the only thing that can be done is buying everyone more time by killing people repeatedly. Or perhaps this murder god is just the god of hunting. There's a lot of killing in nature. It would make total sense for a murder god to be involved in the circle of life, along with a death god and a birth god. [Answer] Maybe the civilian population wants to be granted mercy from an all-powerful god for reasons of fear and self-preservation, especially if the god does other godly things aside from murder (just as prophets allegedly performed miracles). And maybe the ruling class exploit this fear with speeches of "fire and brimstone" for political reasons. Or maybe this god is taking sides in a civilian conflict. A terrorist in one frame can be a freedom fighter in another frame. Maybe god cited 'mysterious ways' with the promise of a better tomorrow. Many potential reasons.. [Answer] I think that the best way to approach this question, is to answer the more abstract issue that is making this question so hard to answer. # Why do people worship Gods? If we look back into history, almost every religion has came to existence to explain the unexplainable. In the era of Roman and Greek society, the Gods were used to explain why lighting would strike and where it came from, or how we fell in love. Later on, in the Medieval era, God was used to explain what would happen after one passed away, or why one had to live a virtuous life. In short, Gods were used to make inexplicable things less scary and explainable. # So why would you worship a God of Murder? To put it simply, murder is scary and not always explainable. Even in modern society, psychopaths are still humans which we find hard to understand and therefore are often the main protagonist in horror movies. Because of that, one could argue that in a society where murder is abundant and often feels random, people would feel inclined to move towards the belief that there is something bigger than them motivating these specific acts and, in hopes of stopping these acts, might start to worship this God of Murder. [Answer] Read most of the other replies here are my ideas: Maybe they have a "warrior" based society in which the strongest man rules, sure this could lead to too many casualties before people got old enough to birth children, however this we can fix by stating a limit such as all men above the age of 20/30/40 summers may challenge the king/leader, should they triumph in killing him they would take his place as king. (There would probably be a lot of rules of conduct for this, such as no poison as that is dishonorable) In addition to/instead of this a different view of life and death perhaps? Maybe getting killed is a great honor, in this way killing would be a rite of passage from this life to the next (seen in a good way), also to keep murder rates up, kids may have to prove themselves through murder to achieve "adulthood" Or maybe they do so as part of a ritualistic sacrifice to their god in exchange for aid. Though in order to be murder it has to be unlawful, so make it so that their nation as a whole is without support of this practice [Answer] Frequently, evil is done with the idea that, if it isn't, something worse will happen. It's a bit dark, but... Consider a world where a powerful god of utter destruction could only be held at bay by the god of murder... and only if the god of murder is supplied with enough power. In order to supply the god of murder with the power to hold off utter destruction, what do mortals do? They commit murder as a form of prayer. At least some of them do, and on a regular basis. This could easily lead to very legitimate questions regarding exactly how much murder is really necessary, which especially if there are other gods in existence as well could easily lead to religious wars. The fun bit here would be figuring out whether the god of murder is actually being truthful about the world's need for him. [Answer] I only skimmed the other answers, so this may have been suggested already. If you have ever read any of the Greek Epic poems (Iliad, Odyssey, etc) the primary motivations for the gods weren't the wants/needs of their followers. They were only concerned with making sure they HAD followers. As such, they wanted to kill anyone who didn't show them (what they felt were) the proper respects and sacrifices, and tried to protect those who did. They were far more willing to let a good worshiper die though. The reason? If you didn't worship all the gods properly, then you were thought to be less likely to worship any god properly. They also had the opinion that, if you weren't showing the proper worships, then those around you would see that the gods weren't punishing you for not worshiping them. If you weren't punished, then those around you didn't need to worry about worshiping that god either. A god of murder seems like it could have similar motivations. Particularly if they're only one in a multi-god pantheon. [Answer] Organized religion around a malevolent god of murder would happen because malevolent people congregate, and would idolize powerful beings that share their values. [Answer] I'd like to answer with an example: In the quite famous manga and anime *Death Note* the main character is given the godlike powers to kill people by only writing down their name (technical details omitted). He uses this power to only kill criminals and so "purge the world from all evil activities". After the population finds out that there is someone actively killing criminals many start to "worship" him. Because they don't know who or what he is, they name him kira (or kirā). Depending on the pronunciation this means "killer". [Answer] Here are a couple of reasons I could imagine: 1. The society, or a part of it, values more intelligence than morality and loyalty. For the these people, solving a problem in a indirect and smart way is highly considered. This includes eliminating an opponent by outsmarting him, or deceiving him. Manipulating an ennemy to make him meet his fate is acceptable for the most radical elements, as soon as it helps strengthen your position in the society. Manipulation and schemes are often a risky business, and may backfire easily because of an unpredicted, random event, so these people would naturally worship a God of Murder, believing he would intervene and help their schemes. 2. (Inspired by @Pedro Gabriel's answer). The worshipers are people that already committed a murder and they believe that murderers go to some equivalent to purgatory to be tortured. They believe that worshiping the God of Murder would protect them to some extent to these tortures. For example, the tortures are conducted by the Goddess of Justice as a punishment to teach them the right way, but the God of Murder is her lover and may distract her from her duty on the behalf of the worshiper. 3. Thar's kind of a non-answer but in many polytheist societies, people were worshiping more than one god at a time, and were not worshiping a given god for all their life. So it would be natural to worship the God of Murder when you plan to commit one. [Answer] I think, that you said it in the question - because the God of Murder really exists (and is immortal Being/God). If other gods have some workshipers, there should be reason for that. You say, that the Gods does not grant powers but they do interract with their workshipers. So they may sometimes give something to their workshipers anyway. Maybe they not grant powers for sure, but on a whim and only sometimes? Still good to take the chance. Maybe they give at least knowledge (of future, present and history). Or even only because the Gods are immortal and probably really old and so they have a lot of knowledge and experience acquired just by beign here for so long and seing a lot of events. Even so weak Gods (just immortal humans, nothing more) would get followers in real world. And Murder is as valuable skill as Combat (even if not so publically praised). See any HongKong Kung-Fu film - there is old master with great knowledge of some kind and he have aprentices. And it makes perfect sence (in the genre). The same apply for poetry, singing, dancing, just anything. For murder too. [Answer] Well, actually you have a real case of murder-divinity cult: <https://en.wikipedia.org/wiki/Santa_Muerte> > > The worship of Santa Muerte also attracts those who are not inclined to seek the traditional Catholic Church for spiritual solace, as it is part of the "legitimate" sector of society. Many followers of Santa Muerte live on the margins of the law or outside it entirely. Many street vendors, taxi drivers, vendors of counterfeit merchandise, street people, prostitutes, pickpockets, petty drug traffickers and gang members are not practicing Catholics or Protestants, but neither are they atheists. > > > In essence they have created their own new religion that reflects their realities, identity, and practices, especially since it speaks to the violence and struggles for life that many of these people face. Conversely both police and military in Mexico can be counted among the faithful who ask for blessings on their weapons and ammunition. > > > Reality beats fiction one more time..O\_O [Answer] People worship to be loved by a higher being they see as perfect. It does not matter how this love is obtained people will always want any god to love them. Just make it so this god speak to his worshippers and explains to them how he loves them and how they are like his children. Like how organised religions in the world today operate, they say outlandish things and encourage some ridiculous/awful things but it is OK because "God still loves you and God knows what is best." ]

[Question] [ Is it safe for my civilization to launch rockets full of hazardous material into the Sun? This question applies to all stars, really, not just the sun. By hazardous materials, I mainly mean radioactive waste. Just so I don't get answers about how the rockets need special materials and it's not very cost effective, disregard the method of transportation for a moment and focus on the part where the stuff enters the Sun. Is there any element/polymer/material/anything we have today that could harm the Sun if we dumped it into it? Although I'm doubtful that there would be negative effects, would dumping large amounts reduce the life of the Sun? (I'm mainly concerned if it changes the life by at least a few thousand years.) If you know how long it would reduce the life, go ahead and put it in the answer, as I'm sure someone will find it helpful. [Answer] If you could get the materials safely away from Earth and actually dump them in the Sun, no, there would be no danger. The Sun is approximately 330,000 times the mass of Earth. To substantially change its evolution, you'd likely to need add - and I'm really just making an educated guess here - something on the order of $\sim0.01M\_{\odot}$, where $M\_{\odot}$ is the astronomer's notation for solar masses. Clearly, that's impossible to attain using just the material on Earth. Each year, the Sun loses roughly $10^{-13}M\_{\odot}$, which comes out to around $10^{14}$ tons. However, [humans produce about $10^9$ tons of trash each year](https://www.nationalgeographic.com/news/2018/05/zero-waste-families-plastic-culture/), meaning that we'd have to dump about 100 centuries' worth of trash into the Sun to simply negate the mass it loses each year. It's also unlikely that any dangerous materials would come back to haunt us. While the Sun does occasionally display bouts of activity, such as coronal mass ejections and solar flares, the material is dissipated throughout space, and the odds of the ejected matter containing our waste in significant quantities are extremely low. Odds are good that it will simply mix throughout the solar photosphere (in its now-ionized form) and never come close to Earth. The solar wind, which is fairly constant, is also not a substantial risk for essentially the same reason. If the Earth were to be engulfed by the Sun, it likely wouldn't cause much of a change to the Sun's evolutionary track. It would, however, be noticeable, causing changes to the composition of the solar photosphere. We've seen this in, among other cases, [the star HD 240430](https://en.wikipedia.org/wiki/HD_240429/240430), which seems to have eaten several terrestrial planets, leading to a significant enrichment of photospheric metals. However, as this is only a change on the surface, its unlikely that the matter will affect the behavior of the stellar core and inner layers, and by extension it will not significantly influence its evolution. If you really want to run the numbers: [The main sequence lifetime of a star](https://en.wikipedia.org/wiki/Main_sequence#Lifetime) is approximately $$\tau=10^{10}\left(\frac{M}{M\_{\odot}}\right)^{-2.5}\;\text{years}$$ where $M$ is the mass of the star and $M\_{\odot}$ is one stellar mass. It turns out that if you compare the cases where $M=M\_{\odot}$ and $M=M\_{\odot}+M\_{\oplus}$ (where $M\_{\oplus}$ is one Earth mass), i.e. the current lifetime and the lifetime if the Sun swallows the Earth, you get a difference of something like 75,000 years. For a star that should live about 10 billion years before leaving the main sequence, that's not much. Now, as I alluded to at the beginning, we *do* have to deal a side effect of the problem of getting matter to the Sun. From an orbital mechanics perspective, I'd argue that it's not a major issue; it's not easy to get to the Sun, but it's far from impossible. However, if the rocket explodes - either on the launch pad or in the air - that waste would be spread out across the surface, and the resulting fallout could cost many lives. Is this idea safe? Once you're out of Earth orbit, yes. Before that . . . maybe not. [Answer] # Dumping radioactive waste into space was actually considered in the real world The idea of launching hazardous waste into the sun is completely absurd on so many levels. Or is it? Let's look at the real world studies that seriously considered it. *HDE 226868* has a terrific answer about the physics involved, so I'll stick to the history. The 1978 NASA report [Nuclear Waste Disposal in Space](https://ntrs.nasa.gov/archive/nasa/casi.ntrs.nasa.gov/19780015628.pdf) approved of the idea dumping waste into space: "Of the five space destinations considered, the lunar surface and solar orbit options are the most attractive..." The report declines to support solar impact disposal of nuclear waste only because it was beyond the rocket power available at the time. A [1981 report](https://www.researchgate.net/profile/Kenneth_Johnson7/publication/326468660_Preliminary_assessment_of_shales_and_other_argillaceous_rocks_in_the_United_States/links/5b4fb5b545851507a7ad61a5/Preliminary-assessment-of-shales-and-other-argillaceous-rocks-in-the-United-States.pdf#page=384) went so far as to rank the different ways of hurling nuclear waste into space. Sending the waste directly into the sun was ranked last. [](https://i.stack.imgur.com/lPNCm.png) The same report illustrated the general procedure for launching radioactive waste into space. [](https://i.stack.imgur.com/8NRid.png) Now to address your question. The idea of shooting waste into the sun has appeared again and again over time, and [a study from 2011](https://digitalcommons.pcom.edu/cgi/viewcontent.cgi?referer=&httpsredir=1&article=1402&context=scholarly_papers) answers exactly what you want to know: > > The underlying principle here is that all matter caught in the sun’s > gravity will lose its structural integrity due to the stress of > gravitational forces and “break up” before reaching the sun. Moreover, > high temperatures will incinerate and completely consume all matter > prior to its reaching the sun’s corona. Specifically, as matter heats > up, it expands beyond its structural integrity, and the heat energy > encountered causes molecular bonds to break. Even the atomic integrity > of elements of atomic number above two (i.e., helium) does not exist > within the sun. Essentially, the intense heat renders such elements > into their composite subatomic particles (e.g., electrons, protons, > neutrons, etc.). Thus, the radioactive nuclear waste never impacts the > sun, having no effect upon its “ecosystem,” and therefore cannot > “damage” the sun. > > > [Answer] # "Waste" is Fuel Radioactive waste is [fuel](https://www.power-technology.com/features/featurenuclear-waste-disposal-reactor-technology-recycle-clean-energy/). We just call it "waste" because we have primitive thermal neutron reactors which are very picky divas and demand fairly enriched U235 (well, if you count 3% as "fairly enriched", which it is, compared to the natural composition). In fact, current LWR reactor technology only "burns" about 1% of the uranium in a fuel rod, leaving 99% of the fissionable material. On the other hand, fast neutron reactors can "breed" more fuel than they consume by transmuting the normally useless U238 into P239. They can also transmute thorium, making it a nuclear fuel source. In general, fast neutron reactors can "burn" just about all the long-lived radioisotopes which occur or result from commercial fission reactions. The only question is how much energy you want to extract. # Breeding, Burning, Garbage Disposal A fast breeder reactor can produce fuel while also producing useful energy. India's nuclear program is predicated on the idea that you can use a small stockpile of enriched uranium to bootstrap an entire nuclear industry that ultimately runs on thorium (of which India has abundant supplies). Whereas, thermal neutron reactors exclusively "burn" the easy fuel. If you are willing to forego some of your power generating capacity, you can essentially make a fast breeder reactor burn all its fuel, which will get rid of more than 99% of the nuclear waste you can produce. In this mode, the reactor will not be as efficient, because unproductive daughter products will build up, poisoning the chain reactions. Even so, the constant bombardment of neutrons will force the daughter products to fission down to a small handful of [products](https://en.wikipedia.org/wiki/Breeder_reactor#Waste_reduction) which are far more easily managed. Note that some of the fission products are commercially valuable, such as [Krypton-85](https://en.wikipedia.org/wiki/Krypton-85#Uses_in_industry) (no, not to defeat Superman), [Strontium-90](https://en.wikipedia.org/wiki/Strontium-90#Industrial_applications), and [Caesium-137](https://en.wikipedia.org/wiki/Caesium-137#Uses). [Answer] Economically it is less expensive to shoot a rocket into deep space and more expensive to send it to the sun. It is even less expensive to crack the waste down and recycle it, by far. For the billions you have to invest in a repeating sunward launch, you can research, engineer and build a transmutation reactor instead and gain lots of value from the waste. Finally, when you start to put strange things into the sun, it's like signalling. Under the assumption that there are aliens and they watch with good spectroscopes, they could maybe see it. So if your universe is hostile, that can be a danger in itself. I don't know if that signal is stronger than our radio emission, though. Probably not. My main point is, sending stuff to the sun is just super duper expensive. Basically everything else is cheaper, even sending stuff away from the sun. [Answer] The sun currently contains about a [Jupiter mass of iron](http://hyperphysics.phy-astr.gsu.edu/hbase/Tables/suncomp.html), left over from its formation. Putting the entire Earth into the sun would not affect its lifetime significantly. [Answer] Jupiter, while not a star, sucks up asteroids and such all the time with no major impact. Considering any trash heap you might drop into the Sun is basically a glorified asteroid and the Sun is about 1000x more massive than Jupiter, you probably won't even notice a difference. [Answer] Use Jupiter instead. * Jupiter is much more easy to reach with a rocket * Jupiter does not have a solar wind that might carry your waste back to you * Jupiter is a gas giant without strong convection The last point is relevant because it means that your heavy nuclear waste will simply sink into the planet **and remain there**. The perfect end storage solution. If you are already committed to dumping your waste in space, Jupiter is the place to send it. It still needs a lot of effort to reach, but there is no safer and easier destination in space than that. [Answer] If one is ready to spend THAT MUCH on disposing off some kind of waste, this begs the question how much dangerous is the waste in the first place. As of now, the most dangerous waste we produce is the spent nuclear fuel and/or its reprocessing tails. Probably equally bad are some highly reactive or poisonous chemicals. In fact, we already have a means of managing it safely on Earth. Not that we always do, but it will still be cheaper (and pretty much more sustainable) than using rockets to move it to space (and even larger rockets to get it to the Sun). Rockets have their own eco implications, we are okay-ish with them because we don't use them much (compared to, say, automobiles). Since you are talking about other stars - depending on your star and other planets in your system, it may be, unlike our Sun, easier to reach the star rather than the deep space. What's more, in most cases it is generally better to keep some form of exotic waste until it happens to be a resource. The history of mining industry knows a lot of cases when a bug pile of waste that no one wants suddenly becomes a valuable resource and people start reprocessing it. Then again, the technology moves forward and we constantly invent more and more unpleasant forms of waste. How about <https://en.wikipedia.org/wiki/Strange_matter> ? If it is able to convert the ordinary matter into itself, it will be equally bad (or even worse) at the Sun - instead of killing a single planet it will kill the solar system (probably later, so open to smuggling and corruption). [Answer] As others have said, the sun can take anything. However, dumping waste in the Sun requires us to cause a lot of environmental devastation on Earth in order to collect the resources for this enterprise; Since not of all the waste will go to the Sun, this process is not sustainable. In order to make this work, we would need some magical technology (in the Clarkean sense: something so advanced we could not comprehend it today) that would zero out the costs of sending stuff to the Sun. [Answer] One aspect I don't see addressed in the answers here with regard to safety is the mass from Earth you lose by doing this. Yes, garbage -- and especially nuclear waste -- is presently a challenge for us *now*, but destroying it by sending it into the sun negates the potential for *future* technology to turn such garbage into useful material. If we were to send all of our garbage to the sun, the Earth's mass would gradually decrease as we exhaust natural resources assembling materials that are used, discarded, and fully destroyed/burnt. So, in essence, we trade the problem of where to store garbage we want to discard for a problem of losing mass that could be useful in the future. Do it over several centuries and I'd imagine the mass lost would be sizable. [Answer] You can toss anything into the sun, at 2.6 Million degrees in the convection zone anything tossed inside will be totally incinerate, course that'll happen before it reaches the photosphere anyway [Answer] Imagine every 1000th launch failing and dispersing garbage all over the launch area or populating near Earth orbit with fast moving projectiles. [Answer] **Two issues only**; 1. Cost (specifically launch costs), it has to be cheaper than processing (or storing ) the waste in question on Earth. This is unlikely at least for the foreseeable future. 2. Launch safety; Technology fails, some types more often than others. Depending on how toxic/dangerous the material you are launching is (and how much of it there is) you need rockets/rail guns etc with an extremely high level of reliability. Which, as noted above is expensive. ]

[Question] [ I have seen a few stories use the programmable magic trope. The most well known I believe is the wiz-biz series, though it's rather old now. The idea is that magic works just like a programming language, you put together words that have meaning and give it power and the spell is compiled and cast immediately, doing whatever you programmed exactly as written. In this case 'power' as a mage usually equates to either having a large number of 'programed' spells you know, or being better at 'programming' a spell on the fly. However, as everyone who has ever programmed knows, bugs happen. Even a simple *Hello World!* program will likely have a missing semicolon or misplaced bracket 1/3 of the time someone writes it. It's hard for humans to write anything without at least small mistakes. The Wiz Biz series addressed this by having a huge disaster in the past due to such mistakes (sort of), and massive effort put into 'testing', as best they could, the spell. Other worlds doing this have always said something about how dangerous mis-writing a spell can be, and yet often the protagonist still manages to code up a spell on the fly with a massive degree of accuracy and no mistakes. In honesty I think all series with this concept have, for all they discussed the potential risk of such magic, failed to represent how absurdly likely and common mistakes would be, and thus how horrible the side effects within the world would be. Let's say I want to write a world that is more realistic regarding the potential of mistakes. However, I don't want a world where everyone who studies magic ends up accidentally destroying everything around them and then themselves within a year of starting to study it. So how can I minimize the risk of disaster due to programming error, while acknowledging errors exist? I'm looking both for how the magic itself could be designed to lower the potential harm and for how citizens of the world may further lower their risk. Assume the world has some level of adherence to thermodynamics. The larger the effect of a spell the more magical energy needed; thus preventing entire world from blowing up when someone typo's. However, there are still lots of horrible small scale disasters to be avoided. I'm okay with some 'bad stuff' happening, but I want it limited in effect if it does. Someone probably won't die from chanting *oya* instead of *oiea* in his spell. Negative effects are fine so long as their severity is low enough to not make magic too dangerous to use, or can be identified before the severe harm is done. At a minimum I'm looking for ways to mitigate the risk for spells written well before they are cast. However, ways to allow someone to write a spell on the fly, or even just modify existing spells on the fly, without lethal risks are good too. In all cases I want to stay realistic to just how common typos or even logical errors are in 'programming'. PS: to give credit while due this was inspired by [How do sorcerers attempt to prevent common people, or other sorcerers, from duplicating their spell scrolls?](https://worldbuilding.stackexchange.com/questions/31691/how-do-sorcerers-attempt-to-prevent-common-people-or-other-sorcerers-from-dupl), though the question has been in the back of my head for a while I never thought of asking it here until now. [Answer] Disclaimer: I'm a simulations programmer, so this is kinda-sorta my bread and butter. Sometimes people even call me a wizard when I solve problems. There's a few major pieces you can focus on. Draco18s mentioned unit testing, which would be a very natural process for weeding out bugs. Take each component and make sure it behaves well in a battery of tests. However, anyone in the software business knows full well that the unit testing is the easy part. *Integration* is the word that strikes fear into everyone's hearts. This is the step where the assumptions you made during unit testing actually get tested, and we see if the parts are actually what we asked for! Its easy to make something do what you want. Its hard to make sure you wanted the right thing. So this is where simulations come in. You need a way to test the behavior of your spell in a low-risk world where, if something goes wrong, you can afford to control it. This might be as simple as having a room which magically emulates what the world outside operates like, only at a vastly decreased level of power. However, there is a mantra that simulations developers are taught: "All models are wrong, some are useful." As much as I love my bread and butter, a product is never truly "ready" until it's been tested in the field, and that means risking the kind of cataclysmic events. Fortunately, you are not the only one who cares about preventing these kinds of events. All sorts of three-letter-agencies are interested in the same issue you are: Federal Aviation Administration (FAA), Department of Defense (DoD), Nuclear Regulatory Committee (NRC). All are very interested in the same thing you are: things not going wrong. So we can look at the sorts of things they demand from their spells -- I mean hardware and software devices, and extrapolate. One of the most important steps to keeping a product under control is the identification of failsafe paths. The software is constantly monitoring itself to make sure the software and hardware is behaving according to expectations. If anything is out of place, a default path makes sure the system remains safe. For example, you might have a very advanced algorithm with all sorts of feedback loops governing a regulatory valve in a nuclear reactor, with the goal of extending the life of the reactor through careful management of temperature. Testing that algorithm is hard. How do you know that it will respond to the particular circumstances it will face in its life? The solution is to have a fail safe. If the temperature (or other variables) get too far off nominal, the advanced algorithm is taken offline and a more predictable, controllable algorithm takes over. This algorithm may not be as capable, but it may be just good enough to shut the system down. In magic land, this may come in the form of parts of the spell which intentionally cut the magical power of the spell if it detects a problem. Accordingly, "safe" spells would always be identifiable because there would be an intentional "weak spot" which the fail safe can sever or control if need be. Also key to these structures is the idea of a "safety critical path." This shows up all over in products for the three letter agencies (can I just call them TLAs?). The idea is that not all of the code is actually *critical*. Some code is optional, other code has fail safes. However, there is always some portion of the software which has no failsafe, just due to the nature of software. This code is tested and audited like crazy. Often they don't use the full capacity of their languages, such as avoiding recursion or allocation of variables. Want extreme safety? Let's talk about the safety critical layers built into Little Boy, the bomb that detonated over Hiroshima. The [actual fuse](https://en.wikipedia.org/wiki/Little_Boy#Fuze_system) was set to detonate at 1900ft above ground, using a redundant pair of radar altimeters. However, radar is a complicated system with all sorts of noise issues that could have caused a false positive, so in the interests of safety-critical operation the radar altimeters were not enabled until a barometric altimeter gave them the OK. The barometric altimeter (a thin strip of metal in a glass container that deflected with air pressure) was not precise enough to detonate the bomb, but it was trusted more, so authority was not given to the altimeters until it declared they were low enough. Even then, the crew of the Enola Gay wasn't about to be ground 0 because some thin piece of metal ruptured, so there was a mechanical timer also on board. The barometer was not trusted unless its rupture was detected more than 15 seconds after bomb drop. Would you trust that on its own? Of course not. The final level of safety critical hardware was a pair of arming plugs, one green (safe) and one red (less than safe). They contained physical wires that connected circuits to turn the whole bomb on. Finally we reach the most safety-critical layer: the physical reliability of these plugs was tested tremendously. The magical equivalent of this would be to make sure dangerous spells are far enough from the caster before they unfold. A fireball may be nothing but a cute little puff of smoke until it gets to a safe enough distance to ignite. Also, individual mages may tune these parameters. A mage with better reaction times may choose to "arm" the fireball at a close distance, while a slower mage may choose to let it fly further before becoming dangerous. Another key trick we see in software is writing code which has provable limitations. If you can prove that the worst damage doable *must* be along a safety-critical path you've analyzed. Consider Google's Native Client (NaCl, or simply salt). NaCl is a fascinating plugin architecture which permits running native x86 code in a safe sandbox. Impossible? I thought so too, until I looked into their approach: * Dynamic code generation is forbidden outside of Google's own APIs for doing so. Thus, all code may be statically analyzed before it can be run. * Privileged instructions are, naturally, forbidden. You have to call Google's API to access things like files. Google installs its "kernel" into your process, and its kernel does the work for you. * The indirect JMP instructions are ever so slightly locked down: you are only permitted to jump to places written directly into the code, or to places whose address is a multiple of 32. Why the last rule? Fascinating really. Consider someone who wants to get around the limits of NaCl by jumping directly into the middle of a Google provided API function. It's really hard to prove that they can't break the sandbox that way. Well, Google wrote their code carefully such that every address that is a multiple of 32 has some sort of HALT or other instruction which immediately terminates. Thus, if you can prove the client code cannot jump to anywhere but multiples of 32, they cannot possibly jump into your code. This may lead to the development of spell "kernels," which are carefully crafted in this way to limit power and prevent it from running out of control. I could see each school of magic having their own preferred set of kernels to build spells from. Of course, there's always the non-software approach. Most software is designed to operate at maximum speed with minimal outside interactions. However, what if interaction was built into the spells directly? What if a spell was actually a part of you until both you and the spell decided to go your separate ways. With this, you might be able to maintain a modicum of control as you try to teach the spell to do things you consider to be "good." This approach may be very popular for druids. Instead of starting from some artificial kernel core, they may start by interacting with some seed of life from Gaia herself, teaching it how to become a good spell, a worthy spell, then letting it free into the world. [Answer] Let's just visit the first lesson of *Magic 101* at the Wizard's University. > > Finally the professor entered the room. Before he turned to the audience, he muttered "*abra*". Now this was to expected; it was a strange tic shared by all wizards that they every now and then muttered, without evident reason, "abra"; indeed it was such a common occurrence that "abra" had become a synonym to "wizard". > > > Now the professor turned to the audience: "Good morning, dear wizard candidates. I'm your professor of magic spelling, and today you'll learn the most important spell of all." > > > The candidates got excited: The first lesson of the first course, and they already would learn the most important of all spells! What would it be? The tension became almost unbearable. > > > The professor continued: "You're certainly eager to learn that spell, but you should know that I'm going to keep an important part back until the end. I know the magic students; after all, I've been one myself, and I've got a host of experience in teaching. *Abra* I know, you'll be eager not only to try it, but to try variations of it. But small variations of spells can easily be very dangerous. *Abra* You may have heard about the large flood five hundred years ago. What is less well known is that it was the fault of a single wizard. He was experimenting with a spell to turn stone to meat, and thought he might be able to make better meat by changing the spell a bit; *abra* well, it turned out that instead the change made the spell incredibly more powerful, turning the wall of a nearby mountain lake to meat. The meat could not hold the water pressure, and the flood was released. The wizard turned the meat back to stone, but he couldn't stop the flood he started. *Abra*" > > > The audience got impatient. They were not here to learn about the dangers of magic, they were here to learn how to apply it! > > > Fortunately the professor now came back to the spell: "OK, so after the word of warning, I'm going to tell you the main part of the spell. It's actually quite short: "ab". That's the active part of the spell. > > > One of the students asked: "What do you mean with *active part?*" > > > The professor answered: "That's what I was coming to anyway. *Abra* A spell consists of three parts: An opening, an active part, and a closing. This is very important, because anything you say between the opening and the closing part is part of the active part of the spell. *Abra* So if you happen to say something in between that's not part of the spell you want to cast, that means you've got a different spell; quite possibly one you'll regret to have cast. This even includes a repetition of the opening part. Therefore you have to be very careful what you say when casting a spell." > > > "So whenever I say something wrong, I'm immediately doomed?" the student asked. > > > "Oh no, fortunately not; that would be terrible." replied the professor. "No, as long as you didn't utter the closing formula, the spell will not go into effect, and therefore you can still correct your error." > > > "But how would I correct that mistake?" > > > "That's a good question. There is a spell word for this, that cancels everything between the opening of the spell and that spell word. *Abra* That is, after uttering that word, you can start over as if you had just uttered the opening. *Abra* And if you continue with the closing, it means you've completely cancelled whatever spell you were starting to cast. Therefore this spell is known as the spell of cancelling. *Abra* Indeed, that is the most important spells of all. I already told it to you: It's "ab". > > > So that was the most important spell the professor was talking about. The students were somewhat disappointed. On the other hand, that safety was valued that much showed that it would be a powerful art they were learning. > > > The professor continued: "*Abra* Now as you know the active part of the most important spell, it's time to teach you the other parts. One part is the closing. The closing is the part that finally releases the magic. Be always sure that you don't utter it before your spell is complete. *Abra* The closing of a spell is "ra". So whenever you started a spell, even if unintentionally, you just have to say "abra" and the spell is cancelled and finished, so you can continue to speak normally as long as you don't utter a starting formula. *Abra*" > > > Again, the same student put his hand up. It had to be a very intelligent and attentive student. His question was: "You said, *a* starting formula. Does that mean there are several?" > > > "Indeed." the professor replied. "*Abra* Actually, for a long time we thought there were just one, but fifty years ago the great mage Hudus found a second opening. It's a very useful one, and the one I'll teach you today. *Abra* But we don't know if there are others we haven't yet found. For this reason, it is a good idea to cancel a possibly ongoing spell you are not even aware you're casting. *Abra* You may have wondered why wizards constantly say "abra". Well, that's the reason. We protect ourselves against unintentional spells. *Abra* Also, it's a good idea to prefix each of your spells with "abra", to prevent it to become part of an ongoing spell you were not aware of *abra*. You better also get into the habit of saying "abra" from time to time, so you don't get caught by surprise." > > > "Ah, " the student replied, "but if you can utter a spell by accident so easily, then why do non-wizards do it all the time? After all, they don't know how to avoid it!" > > > "*Abra* Well, a spell only works if you own a magic staff. It doesn't matter if you have it with you, but you have to own it. *Abra* All of you will be given a magic staff soon; until then, you should get into the habit of saying *abra* frequently. From now on, I want you to start every sentence you say here with "abra"." > > > "And …" > > > "Start wit "abra"!" > > > "*Abra* And what's so special about the newer opening that you said it's so useful?" > > > "Well, if you cast a spell with that opening, it doesn't actually happen. But you immediately know what *would have happened* if you had cast the same spell with the standard opening. Therefore it allows you to safely test spells. And to safely learn them, I want to add." > > > "Ok, so …" > > > "*Start with "abra"!*" > > > "*Abra* so you say we won't be able to actually do magic?" > > > "*Abra* Well, not until you learn the standard opening formula. Which you will as soon as you've passed the first exams and proved that you can indeed be trusted to cast your spells responsibly. *Abra* For now, you'll only learn the newer opening, known as the dry run opening. It's "kad". *Abra* And remember, you should always cancel a possible ongoing spell first. OK, you" — he pointed to another student — "please tell me, what would be the correct way to dry-run cast just the cancelling spell?" > > > The student thought for a few seconds and then said: "Abra kad abra." > > > "Exactly" the professor said. "*Abra*." > > > [Answer] **Make "nothing happens" reality's error message.** Even in a magic world, 99.9% of all events that happen aren't magic. A cow eats grass, water flows downhill, and the sun keeps shining, and a wizard didn't cause any of it. Magical events are the exception, not the norm, so let those small spell-coding errors do exactly what most real coding errors do and cause the whole thing to just fail and do nothing. No explosion, no curses, the wizard says words, and the sun shines and the birds sing and an orc crushes his head with a club. More experienced wizards might have less chance of these harmless "compile time errors" and a greater chance of more interesting "run time errors", as they get better at making sure their spells work enough to always do...something... Actually "run time" takes on a whole new meaning with spell program errors..." [Answer] As a programmer, the single most common result of typographic error in programming is that nothing happens. Syntax errors, misspelled identifiers, etc make the source code incomprehensible to the compiler or interpreter, and as a result the program doesn't run. That would be the fate of most mis-cast spells as well; a "fizzle", nothing of much consequence happening other than the caster stands there looking rather foolish. The potential magnitude of other types of errors depends on the scope and scale of the error and that of the code containing the error. All other things being equal, the "closer to the metal" your code is, the bigger the potential for catastrophic error because there's less in the way to prevent it. In the opposite way, the more your code tries to do, the more it can mess up. So, a spell trying to do something very specific and detailed, like changing someone's physical appearance or imbuing them with innate power, has to be damn perfect, because you're changing the entire person's makeup at the cellular level. Make the same mistake to every cell of that person and they could very well dissolve in a puddle of gibs. Other types of spells, especially those applied to nonliving matter, might be simpler and more error-tolerant because the end result isn't a matter of life or death. To avoid this fate, you can either limit the amount of fine-grained control that is possible with magic, inventing some other means to affect the desired change (a long-lived magical "aura" that surrounds the person to grant an ability or alter their appearance), or you can make the "engine" that makes magic work in this universe somewhat intelligent, giving it a role analogous to a managed runtime in the computer world. That would allow the magical energies to identify the user's intent behind the specifics of their spell and, at the very least, fizzle the spell to prevent unintended consequences, or at best, say "I know what you meant" and act as if the caster's incantation were perfect. The potential for error, perhaps comical, perhaps horrifying, still exists, when the semi-sentient magical energy says "Oh, I know what you really meant" and does something very different from the caster's intent. The Potterverse does a little of all of this. There seems to be an inherent limit to the "resolution" with which wizards can modify the world around them using spells; they can influence reality and make small changes to it, but not totally remake it (though potions, which take much more care and time in crafting than a simple incantation, do allow for more fine-grained effects, with serious potential for disaster if brewed incorrectly). Further, there is some level of sentience embodied in the wand the wizard uses, and an inherent requirement that the wand understand what the wizard intends, and that it wants (or at least allows) them to do it. If the wand doesn't understand what the wizard wants to do, usually nothing happens, but from time to time there are spectacular misfires (especially in the movies). Further, the wand chooses the wizard; anyone with magical power can channel that power through almost anything, but a wand works best for a wizard that the wand accepts as its master, and in the books, wands resist spells cast through them by wizards other than their owner. [Answer] Most modern techniques for improving code quality won't work with magic. Unit testing does not prevent errors from happening; it only prevents errors happening in production. With magic there is no test environment that could burst into flames without anybody caring too much. Carefully designing provably correct code also has limitations. You can make nuclear weapons that don't go off the first time someone looks at them funny, and you can give students spells that teach the concepts without doing anything dangerous, but the ability to write machine code that bypasses all that still exists. A typical student would never be allowed to do that on a computer that controls nuclear weapons, but with magic there is only one environment. To prevent anything too disastrous from happening will require active defense - a group of highly experienced wizards who can install protective spells and deal with any less predictable incidents that come up. Much of this could be automated - for example a spell that detects and disrupts anything using too much magical energy within city limits. Magical barriers set up on property boundaries could let careless wizards eliminate themselves without causing too much trouble for anyone else. With these defenses the city is kept safe, but there is still plenty of scope for causing trouble. An infinite looping spell that summons a live frog twice a second uses an almost undetectable amount of magical energy, so may go unnoticed until you have several thousand of them to deal with. Since defending against all magic takes a significant effort, there would be little if any protection between cities. Something that detects planet-melting levels off energy is probably worthwhile, but generally the first time you cast a spell outside the bubble you are on your own and have hopefully learned to be careful. [Answer] So I really like user3573647 answer in regard to syntax errors just causing the spell to not do anything. But colmde does have a good point of what if it an error in scale, not syntax. (The wizard uses the word for mile instead of the word for inch when creating a fireball) So I have a few ideas: 1. Magic has to be written down first, in a scroll or book. The paper doesn't have to be special, but can have special symbols to tell the universe that it's magic and to pay attention. Once the spell is written, then the wizard would read from it and invoke the spell. The downside is that a wizard might not always have a way to write stuff down. The way to get around that is to be able to take a written spell and bind it to an object as a macro. So if a wizard wants to be able to light his pipe by shooting a 1 inch flame from his finger for 1 second, he could write it up, bind it to his ring with a macro phrase, and then invoke the macro with that phrase any time he wants to light his pipe. 2. If magic is seen as the programming language for the universe, then why not provide a debug window. The wizard begins speaking the spell, and words written in flame appear before him with the spell. Then if he sees an error he can nullify it and start over. The words might only be visible to the caster, or maybe only to wizards. 3. Include a power budget inside of the spell. Say a 1 inch fireball requires 10 magical units to create. So the wizard gives the spell a 10 unit power budget, and then misplaces a decimal point. The spell tries to run, doesn't have enough power, and fails. You could still mess it up, but you'd have to be careless to mess it up really really badly. [Answer] My answer would be to have them run as Macros, with your Wand, Amulet, or other magical construction being the activation sequence. All magic must then be "preloaded" and "run" through these items. You could make it so they have to use their magic tomes to write them across - magic tomes which "check and debug" the spells you write or edit in them, as well as include a quick explanation of their function and effects. It could even be that this is just *the way things are done* and whilst Maging on the fly is possible, it's dangerous, prohibited and frowned upon. And of course, nobody expects the spanish magic inquisition Include things like Power Budgets (hat-tip @AndyD273) and you're on to a winner! [Answer] **The smart move is to [consult with Joe.](https://worldbuilding.stackexchange.com/questions/31904/everything-joe-says-is-true-how-can-he-most-help-humanity)** You will need to be careful in your phrasing and be prepared to pay his hefty consulting fees, but the money will be well-spent. Hey, if magic exists, why not Joe's superpower? [Answer] I'm approaching this from the perspective of someone who regularly deals with the fallout of mistakes in programming. From what I see, there are certain types of errors that would apply equally to a magical world where programming spells results in magical effects: * Input validation. If I want to cast a spell to turn a pumpkin into a coach, for example, that spell should contain validation that the input (a pumpkin) is in fact valid (i.e. not a squash, melon, gourd, or other vegetable). It would be possible to bypass this validation, and hence convert other inputs into something, but I'm guessing that the process would be unreliable - if you put in a cucumber, for example, you probably get a sort of soggy limousine, whereas a cherry would result in a tiny little coach which rots if you look at it funny. Effectively, the process keeps going, but without the correct input, doesn't produce the expected output. In this case, the solution might be to allow these mistakes to happen, or to require a well defined input for all spells. If the input isn't defined properly, it just doesn't work - it's a strongly typed language. * Unexpected interactions. Most programming nowadays involves bolting together pre-existing parts to do something new. These libraries tend to be fairly well behaved, but sometimes they do have some unexpected side effects. Therefore, if I take a module from Spellcraft which handles "fireballs", and a module from Hex-u-like which handles staff-interactions, I might expect to be able to combine them to have a staff that fires fireballs when I point it and say "bang". If the fireball module also knows that keyword, though, I might get a staff which fires a tiny fireball which immediately explodes, with a correspondingly smaller effect than a big fireball which has had a chance to expand to usable size. This one is essentially user error. In real world systems, the effect just happens, but tends to be noticed quickly, unless it's a very specific edge case. * Authorization errors. Forgetting to check whether a given user has permission to do something is really common. Taking my staff from above, if I forget to program in a check that it's me holding it, I might find that anyone can use it against me. More subtly, I might make a magic portal for my local town, allowing selected dignitaries to visit a regional city quickly. I might have a list of known undesirables who are prevented from using the portal, but base it on a characteristic that can be changed, such as hair colour. In that case, it's a logical error that results in undesirable results. Again, this is basically user error. The mistake will probably happen, and it's really difficult to prevent automatically, since it's down to a logical flaw. * Infinite loops. I might set up a well on a barren hilltop to help the locals with their water supply. I might well set it to fill any bucket that is present at a given depth in the well, which seems reasonable enough, until someone drops a bucket, which lands upside down in the well. The spell tries to fill it, the water comes out, and starts building up. The spell keeps trying to fill it, eventually resulting in a build up of ground water, and flooding of the local area. This could be addressed with a kind of power reservoir which a magic user can draw on. Given the power of a single user, they might be able to run a drinking well pretty much indefinitely, based on 10 buckets of water per day, but anything above that starts eating into their reserves of power. For larger spells, such as magically assisted warfare, it might be that large numbers of magic users are needed. In any case, there is a good chance that things *can* still go wrong, but that the most common errors are prevented. Clearly, it's not desirable for a junior magic user to be able to blow up the world, but put enough of them together, with a suitable spell (input: world, output: fragments of world, process: turn input into output with maximum boom), and you get a big bang. [Answer] Depending on the setting, you could have a central authority similar to the Psi-Corps in *Babylon 5*, where all magic users, whatever the level, must be registered members, and then, not permitted to practice magic until they reach a certain level of competency which includes training in QA processses that Cort Ammon describes in his answer. Perhaps each spell they have in the repertoire must be put through testing and be accredited before they are allowed to cast it outside lab conditions. Or it could be a bit like having a driving license. This could be more difficult in a medieval setting where the flow of information isn't as easy, but certainly possible in a more modern setting... Unless you included in the setting that high-level "Psi-Cops" equivalent could detect a "disturbance in the force" whenever a spell was cast. [Answer] If, in your world, magic behaves as programming, I believe the analogy could be extended to broader subjects regarding computer science. After all, computer science is coherent and works pretty well, if you're constructing magic around one of its concepts, taking the analogy further has a good chance of giving you a pretty coherent result. First of all, I disagree with some of the answers suggesting that a "badly written" spell just shouldn't do anything, or "raise an error". True, that happens a lot when programming, but those would just be uncoherent babbling that have nothing even close to do with magic. Saying random words or getting the "syntax" wrong will indeed not do anything, but one could build a spell that is well formatted (it "compiles") but doesn't do what the wizard intended. Think of DELETEing a production database when you only wanted to DELETE a single entry. Pretty bad, right ? You forgot the WHERE statement giving your condition, but your request is still well-formed and gets executed by the server. Well, a wizard could boil every single ocean on the planet, because he forgot to specify a condition on the spell. It happens. To limit and regulate what a spell can do, one could think of power limitations. It makes sense for a wizard to be more or less powerful, just as it makes sense for a computer to have more or less processing power. That would mean you can only cast spells that fall into a level of power consumption you can manage : massive destruction with a single spell will most likely demand a huge amount of power, so unless you're a superpowerful wizard, there's no way you can cause significant damage. And if you are, well, with great power comes great responsibility, and you should be more careful. You're probably much more experienced too, which further reduces the risk. Trying to cast a spell when you don't have enough power to do so will just result in a miserable failure, and you also might exhaust yourself... Try running modern games in Ultra mode on your old laptop and see what happens ! In addition to this concept of "power requirements", the authority/ies ruling your world might be well aware of the issue, and it would seem pretty senseless not to regulate power usage. Maybe a wizard could need specific qualifications to use certain types of spells, or spells that require a given amount of power to be cast properly. Think of permissions : if you don't have permission to delete a file, then you won't be able to do it. Here, you might not be able to prevent a rogue wizard from trying a spell he is not authorized to cast, but since it's against the law, you can prosecute him. It also seems fairly realistic in this kind of magical world to be able to detect if a spell fulfills given requirements before allowing its casting (like a pre-commit hook), and filter spells that don't. The wizard would then know that his spell has been blocked, and no damage is done. [Answer] Several of the other answers takes the approach that programming language means high level programing language. I'm going to take another approach and be inspired by assembler. This has the advantage that there does not have to be any syntax errors, any combination will do SOMETHING. So to make this safe. * Let magic work by weakening the veil to the astral plane (or something like that) in precise patterns directed by the spell words. * Let each spell word take effect as soon as it is uttered. * Make any sensible spell start by a stage where a pattern is etched on the veil to the astral plain, at which point it is obviously visible what the spell will do (This is the key point). Only after that is the veil pierced to add power to the spell. This enables a mage (and possibly everyone else) to see exactly what a spell will do before adding power, and if a mistake is made before piercing the vail the mage need only abort the spell. This framework can be extended by adding further stages. For example 1. Draw pattern for spell effect including targeting 2. Pierce veil to add power 3. Add spell words to extend the duration 4. Add protective details to the spell to defend it from meddling So to summarize, if a mage is forming the spell in a way that makes it's effects visible before adding power placing all the complexity of the worlds assembly programming up front and then make the activation a single command then mistakes can be reduced by letting mages know before finishing casting if it will work. [Answer] I really like [celtschk's "abrakadabra" answer](https://worldbuilding.stackexchange.com/a/31914/37815), but I think we can handle this in a much easier way: **Spells are not programs, they are invocations of programs.** Yes, it's programming all the way, but what you are interacting with, is not the compiler, it's the shell. It's that part of the magic system that *is designed for interaction, and which has the relevant safeguards implemented.* I don't know how you use your computer, but I for one am working on the command line *a lot*. I'm typing stuff like `make`, `git status`, `vim foo.c` faster that you can grab your mouse. *All of these are simple commands that are hard to get wrong*. And, for the most part, I'm only invoking one simple command at a time. So, if I mess up, I'm usually in a state where I can recover quickly and easily. I also know the commands that may get dangerous to invoke wrong. Like `rm`. I *never* say `rm` on the command line without taking a short pause to check whether that's *really* what I intend to be doing. It's basically CONSTANT VIGILANCE! to put it in Prof. Moody's words... Still, there is stuff that those commands *can* do, but which they have been taught to error out on because that just can't be right. If you invoke `rm` with the path `/` (Don't try this!), it'll hopefully just throw an error. At least that's what the man-page says, I'm not going to put that to the test... Mistakes can, and do happen, though. Anyone who does serious work on the command line has lost data due to mistakes. It's inevitable. But for the most part, I can happily hack away without committing serious blunders for months on end. So, the crucial part of programmable language magic is, to program spells that are easy to use in a safe manner and which take extra care not to explode the planet. [Answer] As mentioned above, if I forget to close a bracket or add a semi colon, the program just won't work... This should be a common error for spells on the fly as its common to typo when typing at speed. Like coding, if the spell is done incorrectly, the results should be incorrect to a similar nature. The spell to turn a pumpkin into a coach could have a missed step that turns the Pumpkin into something relatable... from a Pumpkin with wheels or a coach without wheels or a metallic pumpkin or a pumpkin like organic coach... One to the other needs precise steps. If a step is missed, it should have a logical reason to provide the desired outcome... and given where it is an expert spell crafter could see what step was missed and have a laugh. This would play into a spell-debug where the spell crafter may be show to practice each step of his spell and whatch each change from pumpkin to coach as he authorizes each step to happen. Finally, I also have to give a shout out to Spell crafting in the Gargoyles series. Series creator Greg Weisman explained that it was easier to get magic to work if you had specific qualifiers for the spell. This is seen in the origin story where the spell that turned the Gargoyles to stone for a thousand years required the castle to rise above the clouds... its not an impossible feat, but it certainly would require effort to break, but it can be broken (as we see, moving it onto a skyscraper is enough to cause it to become broken). But it also works as garbage in, garbage out as well. In a later episode, a spell is cast over television that will turn "All who see and hear this" to turn to stone. Both of these can follow logic elements that are common in code. Case one: while(castle.height !> clouds.height){ gargoyles.stone(); } Case two: if(this.see() && this.here()){ person.stone(); } else{ //do nothing } In case two, we do see this come into play as the Gargoyles find that their blind friend is unaffected by the spell because he's not able to see the television, thus he always goes to the else condition. Similarly, the Gargoyles don't get zapped because they hit mute, thus negating the condtition of hearing it, but are capable of viewing the footage. [Answer] Powerful programs need powerful resources. To run weather simulation or to crack powerful cipher you need supercomputer. If magic program needs to consume lots of mana to produce big results then a newbie cannot cause disaster - he does not have resources. And you can test new spell by adding available mana during each start. Or maybe even cut off mana source in the middle of execution. [Answer] In conjunction with other techniques others have mentioned you could use a virtual universe (VU) to test all your spells before you release them on to the real universe, in the same way that a programmer might use a virtual machine to get used to working in an unfamiliar operating system. I'm not sure if you should be extra confident in a wizard with a VU which has been totally messed up because they do plenty of experimentation, or worried that they might do the same to you! [Answer] # Syntax errors produce a puff of harmless smoke If you say a spell wrong, nothing happens. In real world programming, changing a character somewhere usually ends up producing a syntax error, or at worst will change a string or number to something different. Spells would be much the same. If you mispronounce a word, you probably will cast a dud. If you're unlucky, the scale of your spell might be different, but you likely won't summon a chicken instead of shooting a fireball. There could be a way to interpret the smoke patterns which vary based on the mistake. # Simple spells are less error prone Hello world basically always works as intended, assuming it compiles correctly. Simple spells don't usually have issues and are easy to cast. # Most errors are simply not catastrophic Most real world software isn't life-or-death. Often, the worst-case scenario is crashing the program or opening a security vulnerability. Yes, you can definitely do some serious damage, but most of the time, software bugs don't kill people. As long as spells aren't messing with life-and-death type stuff like healing, transformation, and summoning, you don't need to worry much. Large-scale spells like rain dances would be frowned upon or banned because of the possibility of minor errors doing severe damage. # Spell safety This world would likely have spell safety practices, much like gun safety. It would be bad practice to point spells at anyone and wands (or whatever channeling implement) would be treated like deadly weapons. While spells are not generally harmful, there is a real possibility of unintended effects doing harmful things. Perhaps you might intend to spawn a brick, but you mess up and the brick is launched forward at a high velocity after being spawned. # Licensing Because of the risks involved, healers should probably go through intensive schooling to ensure that they do not make deadly mistakes. They will rely exclusively on known spells rather than creating new ones. They would almost definitely need to have a license, much like doctors and nurses do in the real world. [Answer] A spell needs a program and an infusion of willpower to work. A sorcerer has to learn how to idly kinda wish for something to happen, and to do that reliably. It's possible to debug most spells by putting in a teeny amount of willpower and observing the results. A misbehaving fireball spell produces a few sparks when it goes wrong when the sorcerer is using debugging levels of willpower. Naturally, there's the possibility for a disaster to happen, should a sorcerer use a spell that incorporates willpower enhancement. That's a somewhat discouraged magic pattern. There's also the problem when the sorcerer gets surprised or panicky. People who try to use spells without the training usually manage to mess up with significant levels of willpower, not having learned to use just a tiny bit. This at least keeps the numbers down. ]

[Question] [ ## QUESTION In the real world, the [history of law](https://en.wikipedia.org/wiki/Legal_history#Ancient_world) in pre-industrial states is as sprawling and complex as can be imagined, and includes all kinds of unique and fascinating systems, from the Code of Hammurabi to the Gragas, and much else besides. But worldbuilders who are interested in creating a fantasy legal system need to set priorities, and organize their information to create a convincing but alien legal system in the broad strokes. To this purpose, even a basic theoretical approach to structuring a fantasy legal system could be helpful for worldbuilders lacking strong knowledge of law or legal history, among whom I count myself. **What are the vital questions I should ask myself when building a fantasy legal system?** ## CRITERIA Anyone can design a list of laws and penalties, decide which crimes warrant harsher punishments, and determine which social groups the law is designed to serve. All that is pretty trivial, so a good answer needs to find questions the average worldbuilder might not ask. Just for some throw away examples: Are lawyers professionals? Is the prosecution independent? Do some witnesses carry extra legal weight? Who is obliged to carry out sentence? There are certainly other questions to ask and better ways to organize them, but that provides a decent starting reference. Assume ... * A generally Earth-like world with humans. * A classical or medieval point of reference, 1500 AD or before. * A focus on law relevant to most stories. So criminal beats civil, without necessarily excluding it. The importance of other forms of law was pointed out in the comments, so I'll strike this point. * No magic. An ideal answer would hit the most important questions, creating a shortlist suitable to a classical or medieval society. Drawing on historical or real world examples to show why a particular question is important is encouraged but not required. --- Just to be clear, I am not asking for *all* of the questions that are relevant to creating a fantasy legal system. That would be crazy. So while you're more than welcome to fit whatever you please into an answer, what I'm asking for is the *most important questions* that your average worldbuilder might not think about, preferably structured so that by answering them you can create the skeleton of a legal culture. [Answer] Assuming you have a basic list of *things not to do* and *penalties* set up you may wish to start asking about the **bureaucratic process**: * Who can *accuse* people? Everyone, or only the elite? * Who can *catch* people? Is there a police force? Are they from a government or a company? Or can everyone try to *right the wrongs done to him/ his family/ ...*? * Who can *judge* people? Are there dedicated judges? Or does the enforcer put them on the pillory and all the townsfolk can *judge* them? * Who can *free* people? Are there processes to plea for not being guilty if evidence is found later? Is *evidence* even important? Have there been cases where people were freed or are there only legends about that? * What do you do with *people who dodge the judgment*? Maybe they escaped - are they excused if they didn't have to pay for the crime in 5/10/50 years? Will the punishment be more severe? * Who *records* cases? Are there big libraries where everything is documented or does the big government/company not want to make this information public? * Who *can become one of these people*? Is it easy to become a judge/enforcer/accuser/... or do you have to pass rigorous exams? Do you have to be from a certain caste to even be considered for the job? * How many people are there from each job? Is an enforcer rare? Are they common and seen on every corner? * Are people doing the job? Which parts are automated? * How long does each stage take? Is it a matter of hours from *accused* to *executed*? Or does it take a couple days to catch someone and years to pass the judgment? * Where are people held while the judgment is still in process and who cares for them? Are there prisons? What do they look like? Are they in remote places? Who are the guards? * How are people cared for that are accused/judged? Are they taken care of like normal people, or is an accusation already bad enough to warrant them being treated like lepers? This list can be expanded of course, for example with the suggestions from [Miller86](https://worldbuilding.stackexchange.com/questions/104911/what-questions-should-i-ask-myself-when-designing-a-legal-system-for-a-fantasy-w/104914?noredirect=1#comment316883_104914): > > is there a legal document codifying all of the above, do multiple documents cover it, or is it tradition? For real-world examples, see the US constitution versus the UK constitution. Additionally, what happens when those who make the laws go against tradition or the codification documents? Quis Custodiate Ipsos Custodes (or, Who Watches the Watchmen) > > > Or to paraphrase and expand the comment from [OhkaBaka](https://worldbuilding.stackexchange.com/questions/104911/what-questions-should-i-ask-myself-when-designing-a-legal-system-for-a-fantasy-w#comment316929_104914): * What is the history of the different institutions? Why was the system/ the institution/ the job initially set up? How long ago was this initial setup and what changed in this timeframe? What was the original goal and how does it differ from the current goal? * Who was/ were the creator/ s? What was his/ their goal? What principles did he/ they value? What do the people value that are in control *now*? * Where do you see these goals? Are there parols that are often used? Symbols? Idols? Monuments? * Where do you see the rules and guidelines in the everyday life? Is there a poster in every street? Are there posts on big internet forums? Are there radio or television shows? Are there certain people who are the *face* of the different institutions? In addition like [Kamil Drakari](https://worldbuilding.stackexchange.com/questions/104911/what-questions-should-i-ask-myself-when-designing-a-legal-system-for-a-fantasy-w/104914?noredirect=1#comment316956_104914) mentions: > > Under what processes/conditions can the system be changed, if any? > > > * How often is the system changing? Has it been stagnating since it was first set in place? Or did it slowly change towards what it currently is? If so, is there a goal defined by some entity in the past or the current times? Does the *goal* change over time, for example with each new *leader*? Or is there a self-improving system in place? If so, is it flawless (hint: nothing is flawless)? * What happens to people who oppose the system? What happens to people who oppose the *changes* in the system? Can the system adapt to new circumstances, whether they are social or environmental in nature? * Are there democratic processes in place to guide the system? Oligarchic processes? Aristocratic processes? Dictatorial processes? How does the system work in the context of your general governmental structure and are the people/ entities responsible for controlling the legal system bound to what your government/ population wants? [Answer] **Areas of Law** The first question is how many areas of law you want. For instance, we have common law (basically, contract law), criminal law (basically, 'breaking the law') and a new developing field around 'licencing law' (as in a software licence to use). Each of these areas has distinct methods and trial practices. **Contract Law** In contract law there are at least two modern approaches. The British common law insists that there be consideration on both parts. A bet, for instance, is not enforceable. Under the French Napoleonic code, a promise (one-sided consideration) is enforceable. **Adversarial vs Negotiation** In the British system, the two sides are very distinct (prosecution and defense) and they each argue only their own side, trying to circumvent the truthfulness of the other side. In the Iroquois confederacy the emphasis of the courts and legal system is to thoroughly investigate the truth. There are no 'sides', no 'opposing arguments'. only a mutual search for figuring out what actually happened. It is not a case of the prosecution asking questions, and then the defense, but the 'judge', with appropriate counsel, asks all of the questions, pursuing both sides of the truth at the same time. The goal is healing, not recrimination. Japan tends to use a non-adversarial system. The investigators are responsible for looking at all sides, and in presenting all of the facts. Guilt or innocence is determined by the facts, not a judge. 'If you are guilty, you will be found guilty, If you are innocent, you will be found innocent'. You don't *become* guilty by the determination of the court, you become guilty by *perpetrating the crime*. **Behavior vs Intent** In criminal law, is the nature of the offence in the actual behavior, or the intent of the behavior? In Canada, the emphasis is on intent. For instance, it is not good enough that you walk off with something for it to be theft, you have to have INTENDED to walk off. Picking something up by accident, or in confusion, for instance, is not intent. **Punishment vs Rehabilitation** Is the purpose of the 'sentence' to punish, or to discourage future actions, or is it to rehabilitate the person? Drug addiction, for instance. Or kleptomania. **Crime vs Illness** Related to the former is the concept of what deviant behavior actually *is*. Does the society consider it *criminal* or a sign of treatable *mental illness*? This is really important, for instance, in terms of behavior modification and attitude change and deviant personality forced alteration. Should sex deviants be forced to undergo treatment? Should they be held in protective custody until they are cured or stabilized? Should continuing treatment (addiction, for instance) be made mandatory? China, for instance, has a *criminal* legal system that considers all crime a social deviation, and therefore should not be punished but subject to remediation through re-education, social pressures, or mentoring. You remain under state control for as long as remediation takes. Those who are deemed to not be rehabilitatable are permanently removed from society. **Protection of Property or Society** American criminal law tends to be all about protecting property rights and economic assets. Theft under and theft over are treated differently. Robbery is treated preferentially over assault. Social implications of the crime are usually all but ignored, until the victim impact statement. An alternative system would be one that considers social implications as the crime, not the economic loss. An action that causes PTSD, for instance, irregardless of the cause, would be punishable. An activity that undermines social trust (deception and lying, for instance) would be prosecutable. Bullying would be a crime, as would be belittling someone. Inciting to unrest, hate, social upheaval, promoting negative emotions. Social and psychological health and stability would be the prime consideration, not economic health. The denser the population, the more this would be a factor, I would think. Getting angry could have really bad consequences, so inciting someone to get angry would be a serious crime. [Answer] You're focusing on the legal system here, but you need to look at all the ways that, historically, such systems have been circumvented. How your legal system deals with the inevitable corruption and loopholes is fully as important as its normal intent and function. What are the origins of your legal system: what philosophy underlies it? Is it based on the idea of the rule of law? Was it developed by an aristocratic elite to serve their interests? Is it based on a state religion, with laws enforcing various key points and customs and so on of that religion? The answer will have a major impact on what laws are made, how they are enforced, and so on. Money is an old, old consideration, and significant for precisely that reason. Are there significant penalties for bribery, or regular investigations of suspected bribery? Are such penalties instead trivial, such that judges (or lawyers, or whoever) have no material reason not to accept bribes? Are legal officials somehow protected from the law themselves, held above it? What is the societal view of bribery (also patronage and nepotism; views on those matters will influence this one): is it tacitly accepted as necessary to get anything done, or frowned upon, or actively condemned? Independence of legal officials should also be considered. Do they serve only at the will of the king or president or whatever the leader is called? Can they be dismissed at will, or are they protected from arbitrary dismissal once appointed? Are they appointed at all, or elected in some manner; elections dictate a need to appeal to the majority, which will influence their rulings at some level. The power of legal officials: can they prosecute and investigate anyone, or are certain groups (nobility, for instance) effectively protected from such attentions? Are top figures in the government immune to prosecution, and if so to what degree? Can the government overrule the law with ease, or is it itself bound to respect the laws it creates; if so, how is this enforced? For that matter, what happens if the legal officials themselves violate the law; can they be removed, jailed, fined, etc., for that, or are they able to violate the laws they are supposed to enforce? For that matter, is there a formal legal profession at all? Or is justice administered locally, on the spot, by some respected figure (the town mayor, for instance) without any lengthy trial or recourse to appeal? Your society might not tend to a legalistic perspective with its heavy focus on technicalities and minor details; there might not be a written law at all (or not much of one; think something like the Ten Commandments being the extent of written law), only an implicit code of conduct. [Answer] I would like to build on Secespitus' answer (which I upvoted). * What are the motivations of the people involved? Individual motivations win out over the needs of society so long as the individual has the power to control the population (think "king"). If yours is a merchant-driven or guild-driven society, then the rules of trade will massively influence law as a whole. The same can be said of a military state, or a parasitical state (one that is small and in close contact with a much larger society). * How old is the civilization/society? Do various races live together? Do they have equal or unequal representation on the "ruling councils?" * Does the society have a philosophy or belief that they wish to preserve? Like a religion or an ancestral tradition? * How well armed is the populace? Kim Jong-un of North Korea does not have a well-armed populace. The U.S. does. It's easy to maintain martial law in N. Korea, it would be a bloodbath to try and enforce it in the U.S. (This is a very two-dimensional way of looking at the usefulness of the U.S. 2nd Amendment, but it's not invalid). * Has there been a pro-people leader or leading council now or in the past? Such would pass laws protecting the people even if the people aren't strong enough to demand the changes for themselves. * Is there a middle class that's tired of being treated like the lower class? Again, it's two-dimensional, but this is somewhat how Britain's Magna Carta came to be. * Finally, how large is your civilization? Densely populated cities need services: water, sewer and trash, road and bridge maintenance, food supply, etc. The rules regulating services have a huge impact on the legal structure of your world. The same can be said about trade between cities, the effect of outlaws/brigands/highwaymen and the regulation of ports. Simplifying outrageously, nobody minds taking advantage of their neighbor for a dollar, but everybody minds having their advantage taken. [Answer] One main question is how big is the government? Often times there was no codified legal system. The commoners would be brought before a magistrate who would hear the case and make a ruling. Noblemen went before the king or someone appointed by the king. The king will also tend to pass down laws such as: anyone who is caught stealing will have a hand chopped off. There is not procedure for creating that law and usually none given for truly defining what constitutes "getting caught stealing." Though some rulers are better at that than most. Once things get big enough that the king cannot rule on all issues dealing with noblemen, they tend to for a written or unwritten set of laws or traditions to handle things before they get to the king. This keeps the king's power structure in place by making sure that things are fair for those who keep him on the throne. If there is enough communication between regions, there may be codified laws and procedures for the peasants to prevent them from resenting their lord because someone else's lord rules in a different way. [Answer] One thing that other answers only briefly touch on is the process by which those accused are found innocent or guilty. In our world, presumption of innocence is the norm, and has a history dating back at least to the [legal reforms of Antonious Pius](https://en.wikipedia.org/wiki/Antoninus_Pius#Legal_reforms) in the 2nd century AD, but it's not the only possible model - some of the old Germanic law codes required the accused to take an oath of innocence, for example. The other major thing that ties into this is the system of obtaining evidence with which to prove guilt/innocence. Nowadays we collect evidence such as forensic evidence and camera footage, but these were largely not available in history (and so, for the most part, in fantasy). Instead, both parties would bring in '[oath helpers](http://www.thefinertimes.com/Middle-Ages/law-in-the-middle-ages.html)' who swore that they believed the accused to be innocent or guilty, with the accused's guilty status resting on whether or not their oath was considered stronger than that of the accuser. These are two extremes, and most historical (and current) legal systems sit somewhere on a spectrum between them. **When designing your fantasy legal system you should consider the availability of evidence**, which will largely determine where on this spectrum your legal system sits. [Answer] At a very high level, the key question is **how does the legal system fit within the culture?** For example, in a primarily oral culture knowledge is passed from generation to generation by telling stories. In that kind of setting you might expect stories to be important in the legal system. Arguments for the severity of an action, whether circumstances mitigate, and what an appropriate punishment would be can all be made by analogies between the current situation and the traditional stories. In a highly literate culture knowledge is communicated in a more abstract form: this is the kind of setting in which arguments hinge on the meanings of words. Precedent can still be important, but it's the precedent of previous cases rather than of legends about heroes and gods. Talking of gods, the culture's religion is also very relevant to the legal system. Not only because knowing what the gods find acceptable and unacceptable drives what the human legal system considers acceptable and unacceptable, but because gods who are actively involved in the world may take an active part in justice. Are religion and politics separate or closely intertwined? Are the gods involved in determining the truth of the situation - perhaps through trial by combat or something similar, or perhaps because judgement is a priestly rôle? Are the gods involved in administering punishment? Are (most) witnesses and judges compelled by fear of divine wrath to be honest and just, or are their decisions on honesty driven by more complex motivations? [Answer] Looking at this from the perspective of 1500 AD or before, one must consider the belief system of the culture. Do they believe in the omnipotence of a supreme being? Is the ultimate judgement in society's hands, or is it in the hands of a deity that supersedes the citizens? It has been said that the Constitution of the United States is particularly silent on moral issues (abortion, homosexuality for instance), because at the time it was written, these were deemed to be the domain of God. Humans had no right, nor business, to dictate morality or moral decisions that are more appropriately left to God. Ultimate moral authority was in His hands. It assumed that everyone acknowledged the rule of a supreme being, irregardless of the manifestation of the organized structure of the religion, and would abide by and subject themselves to such moral religious judgments rather than man's pronouncements. God would judge, so there was no reason for humans to judge. As humans evolved into a more secular society, where a deity became less and less significant in moral decisions, the law was required to speak more and more to these issues. Central to this is the nature of the penalties for lying under oath. Pre-1500's, the penalty for lying under God was dealt with by God Himself. It was not a human concern. God, or whatever divinity, extracted far greater penalties than a human judge could ever administer. So an oath under God was determined to be as factual as anything could ever be. An oath was unassailable evidence, and when physical evidence contradicted it, the oath was to be considered more truthful. The king or queen, or whatever the highest earthly title, was usually considered to be an adjunct of this deity, and was considered incapable of lying. Their word could not be questioned. Not only did you not dare to call the King a liar, you *couldn't* call the King a liar. It was nonsense to do so. It was impossible for the king to lie. As we grew more secular in our laws, penalties against perjury became more of an impediment to lying than one's belief system. After the British revolt of the middle merchant class, the King lost his invincibility privilege, and became accountable to the law and to the process of the law. **TL:DR** In the words attributed to a very wise person, it is very important to distinguish what is the Lord's, and must be rendered unto the Lord, and what is Caesar's, and must be rendered unto Caesar. That is, what part does secular law play, vs the part divine law plays, in judgement. [Answer] Just one more question I would keep in mind: what is the goal of punishment? Retribution against the criminal? Protection of law-abiding citizens, with not much attention given to the criminal any more? Re-socialisation of the criminal? The choice of focus here vastly changes sentences and conditions in prison, possibly even how judges are selected. [Answer] Given the date 1050 CE-ish, it is worth noting that most of the "civilized" places in the world at that time didn't have "law" as a concept for the most part. In China (at nearly its modern extent), Europe, West Asia and India, for the most part, there were feudal systems in which the only law was that the lord has absolute power over those below him and was subject only to people above in him the feudal hierarchy. In China's Confucian philosophy, it was the predominant view that rule of good men was a better path to a good society than rule based upon abstract laws. So, there was no equivalent to a set of codified laws or even a British style common law. The only law was that the relevant lord had absolute power to make decisions and resolve disputes, and you hoped that the person who was doing that was good and just and wise. Rule of law was considered an invitation to clever but evil lawyers that who not advance the good of the society to take control. While this might seem foreign, this is basically how almost all modern firms (both businesses and NGOs) handle their internal affairs, and also how most families handle their internal affairs. Abstract, universal laws are tools to allow strangers who are equal in status to deal with each other. It has no application within hierarchical organizations whether they are families or vast feudal nations. [Answer] My answer is a short one, and not at all exclusive to any of the others (and I grew a bit exhausted trying to summarize them, and so if any covered this... my apologies.) In any case. My answer is more for AFTER you decide your legal system... or perhaps when polishing it up and then after. Put yourself in the position of a few brief characters... one who enforces the law, one who tries to survive within the law... and one who looks for a way to exploit or circumvent the law for personal gain. Give each a very short story or two wherein they're encountering your legal system with these motivations in mind... and see if they help you perfect that legal system, or spin off useful material for writing prompts in how folk react to it. ]

[Question] [ A new species with technological potential is starting to multiply and subjugate the Earth. What resources can it harvest from human (our) cities which were destroyed 30M years ago (humans are gone now)? Assuming some of the ruined cities still remain close to the surface and were not buried miles underneath by tectonic activity. Split from the original question: [Post-apocalypse: large mammals erased, can homo sapiens 2.0 build civilisation?](https://worldbuilding.stackexchange.com/q/117172/28789) [Answer] Nothing. 30 million years ago Antarctica developed its ice cap. The Alps STARTED to rise in Europe. The place now known as South America detached from Antarctica and started drifting toward North America. The Great Pyramid of Giza was built around 4500 years ago. 30 million years ago that part of Africa didn't exist. To give extra perspective. The WHOLE region known as Italy and Greece wasn't there. There was water. Glass needs around 4000 years to decay. You could make a glass bottle and wait for it completely decay and then make a new one seven thousand five hundred times. 7500 TIMES. During that 4000 years there would need to be some kind of change that would stop (because slowing down would do nothing) the decay only then would it survive. [Answer] The current answers are assuming you mean from 2018 human cities. Since it will probably take some time for our ultimate demise, some technological advances could take place that would allow a species 30 million years later to detect human presence. It is lucky that a resourceful and vain group of scientists thought of this notion in 21XX. They developed the technology for nanobots! Each nanobot, as part of its self replicating "DNA", contains the information from the entirety of human written works. The nanobots, while ultimately being of the '[gray goo](https://en.wikipedia.org/wiki/Grey_goo)' type, reproduce very slowly. So they themselves have been migrated by geological events. They are also fragile, so extreme heat, cold, pressure render them unable to reproduce. They have thrived though in places containing unique compounds and higher than normal carbon content (i.e. cities and garbage dumps!). Of course 30 million years is a very long time, so the nanobots also reuse the corpses of non-functioning nanobots. What is left 30 million years later, after millennia of nanobot reproduction and mutation, is areas of the Earth containing pockets of nanobots, each slowly reproducing and containing encoded information from a species long gone. ## ADDED BONUS PLOT The nanobots are quite small, and basically indiscernible from "oddly colored dirt". The information encoded in them is basically irretrievable by all but the most sophisticated of beings. The nanobots, while small, do have primitive locomotion (so they can cluster near high resource locations). They find carbon-based life forms especially delicious, particularly the large spongy masses known as "brains". They are slow to reproduce (decades), so an organism may live its entire normal life with a nanobot embedded, and not notice too much. There is an unusual effect when a nanobot or a few hundred, invade a brain. The host organism's neural activity is altered by the molecular structure of the nanobot (which contains our encoded information). It manifests itself first as hallucinations, or wild imaginative thoughts. After much training, and the nanobots thoroughly embed themselves within the host, the host is able to enter a trance-like state where vast new worlds of information are available. This leads to the host species having cultural or technological advances that leads to... ## REALLY? You may be thinking that nanobots that just happen to cause changes in brain functions is a bit far-fetched and there would be a pretty slim chance this would actually happen. Unless they were designed to do that very thing! Neural augmentation was researched for many decades to develop the technology. It was first introduced by the clandestine, shadowy, military-industrial-complex to help create super soldiers. Of course the technology leaked into normal life. In 21XX, *everyone* (except poor people of course) had their memory improved by "neuraugs". They were easy to install, just take a couple of pills, and the nanobots were absorbed into the bloodstream where they were then transported to the brain. The cutting edge research was also geared at giving new capabilities, such as: * The ability to use our existing vocal chords to more densely encode information, and decode this information with our existing auditory system. The neuraug soldier could communicate entire battle plans in mere seconds. * The ability to filter visual signals to improve vision at night or in high brightness, or in dusty environments. * The ability to simulate sequences of physical events in a highly-parallel manner, allowing for increased performance in hand-to-hand combat. ## BUT WHY? So 30 million years later, why would the newsapiens be interested? At first, maybe they aren't, or they misunderstand what the nanobots are. At first, they appear to make people sick, and are classified similar to viruses (neither dead or alive). However, once one segment of the newsapien population discovered how to harness some of the neural augmentation capabilities, an arms race unfolds. The newsapiens don't know how to create the neuraugs, and they cannot be grown in a lab rapidly enough to satisfy the need. So they are harvested from the few sites on the Earth where they are abundant. ## OTHER CONSIDERATIONS Since the newsapiens had a different evolutionary path from humans, their cellular makeup is similar enough for the neural encoded information to be decoded, but perhaps not as effectively and because the information was encoded from the perspective of a human host, some of the sensory signal manipulations may have novel effects that weren't originally intended. For instance, if the newsapiens have bioluminescence, or electroplaques, or echolocation, these could all be enhanced in humorous, sinister, or benign ways. (for instance, perhaps the only effect on the newsapiens is to cause a particularly attractive pattern in their bioluminescense output. So the only reason newsapiens are interested is to increase their chances at mating?) Also, there could be mutations of the neuraugs over 30 million years, such that the neuraugs themselves have developed in to "species", each with its advantages and disadvantages. [Answer] **Nuclear waste**. Over 90 % of naturally occurring uranium is U238, but U235 is used in nuclear reactors because this is the isotope that is fissile. Future earthlings would find large unexplainable deposits of U235 around the sites of old nuclear reactors. [Answer] The oldest cities we have on Earth date back to some thousands year ago. Way too young to give a reliable metric on what could remain after 30 million years. But we can give it a shot based on our current knowledge on how various (broad) classes of materials would behave to ageing: * **Oxides based materials** (glass, pottery, bricks, concrete): with them we are lucky, as being already oxidized it's relatively hard to get them to a lower energetic content. The major risk comes from physical damage, reducing them to dust. I would speculate that these materials would leave various clumps of different sizes. The water soluble one would be probably gone. * **Metals**: most of them will be back to oxide state, and some of these oxides would have been solved in water and carried away from rains. Gold will stay gold, so it would be possible to find some deformed gold jewelry or tooth. * **Carbon based materials** (plastics): hic sunt leones. Plastics have the weird feature of being rather sturdy but also have an high energy content. I have the feeling there could be two paths: one path leading to simple physical degradation, with plastics being reduced in size and ending up as dust/sand, chemically almost unchanged, another path leading to the evolution of micro-organism relying on plastic as energy source. Think of it: a lot of unoxidized carbon, waiting to release its chemical energy. Over 30 million years something could evolve. * **Organic materials** (fuels, wood, etc.): unless they have found the right conditions to turn into fossils, they would have been chemically degraded by other organisms. [Answer] 30 Million years means: * Multiple ice ages in temperate latitudes, reforming the ground over and over. Most cities in Europe and Russia and northern North America scraped clean by mile-high rivers of ice over and over. No traces left at all at the site, and curious jumbles of oxidized rich ores at the edges and drop-areas. * City ruins along slow rivers buried by sediment and then fossilized. Cities along fast rivers long eroded away, nothing but air remaining. * A somewhat different sea level, so most coastal city ruins either buried miles inland on the coastal plain or submerged near-offshore. [Answer] Maybe you could locate cities by the curious composition of metal oxides they might leave behind. We use a lot of quite rare elements in our every day appliances; gold, silver, titanium, tungsten, platinum, etc.; and their co-location in a single place might be hard to explain otherwise. However, **what you could easily find is [Fort Knox](https://en.wikipedia.org/wiki/United_States_Bullion_Depository)**. Gold has the trait of being extremely inert, so much so that it's always found in its metallic form. It's just dispersed as very fine dust normally, which is what makes gold mining so hard. You have to go through tons and tons of material to accumulate meaningful amounts of gold. And this is precisely the point: We humans are by far the most effective aggregation process that gold has ever seen. We not only mine it, we also have the habit of piling huge amounts of this metal together. There is no natural process that comes close to us in this. And Fort Knox is the largest of these piles. Because gold is so inert, the pile at Fort Knox will have a very hard time dissolving. Chemistry just won't help. Wind and water are powerless until the gold is ground back to dust. And even then, the dust won't spread far quickly. So, when all the concrete and steel of Fort Knox have withered away, nowhere to be found, and the gold has been ground back to dust and mixed with the surrounding dust, the pile of gold will remain as the most strongly enriched deposit of gold anywhere on the planet. [Answer] Any major city that wasn't subducted by plate tectonics would at the very least be a good iron mine. It will probably be iron oxide, but it was iron oxide when we first dug it up. [Answer] OK, let us start with: after 30 million years, what geological activities did not to the cities, weather, erosion and vegetation did. Even plastic materials are gone, rubber, stainless steel, glass...everything. You'll be lucky to find the pattern of what used to be the cities well hidden inside the greenery. The polar settlements have been devoured by ice. The mountain communities have long been destroyed by avalanches that inflicted the final blows to the lack of maintenance. Any leftover artifacts save gold and crystal jewelries will be too scattered to be considered more than a lucky find, and by then any incision on the gold will have been carefully smoothed so that it will be next to impossible to consider them as ancient artifacts [Answer] While your new species might have trouble harvesting anything from the previous human civilization, see all the other answers for details, they may still find out about humanity in a limited way. An article from [Space.com](https://www.space.com/12846-apollo-moon-landing-sites-flags-footprints.html) in 2011 put the survivability of the Apollo missions equipment within the time range you're talking about. > > "They won't be there forever," Mark Robinson, an Arizona State University scientist and the principal investigator of LRO's camera, said in a news briefing today. "The moon is constantly bombarded with micrometeorites. These are very, very small particles that impact at very high velocities." > > > "In human terms, it may seem like forever, but in geologic terms, probably there will be no traces of the Apollo exploration in, let's say, **ten to a hundred million years**," Robinson said. > > > [Answer] **Nothing will be harvestable.** The oldest exposed ground on Earth is found in Israel's [Negev Desert](https://www.livescience.com/3542-oldest-surface-earth-discovered.html), at 1.8 million years. Most exposed surface lasts much less time. That means that the ground your cities stand on will have been [subducted](https://en.wikipedia.org/wiki/Subduction) or [eroded](https://en.wikipedia.org/wiki/Erosion) away. In 30 million years you will have to do some digging to find any remnants, and they will have been processed by grinding. This is why fossil finds are so rare, given the number of living organisms that have ever lived on Earth. Your next civilization might get lucky and **find** a gold ring or titanium implant. But there is not enough quantity anything left to harvest. [Answer] Well, this looks a little like a cart before the horse situation. See, in this scenario, it seems you are wanting to set things up for story development. The thing is you need to decide what resources you want your new species to have access to. Then you need to do some research and find out how long those resources will still be available. Then set your time period since the cities were destroyed based on those criteria. Also, you need to consider whether the destruction of humanity occurred near the present or much further in the future than the current time period. (In the next 20-50 million years possible candidate species might feasably come from present day Octopuses, most Primates, Bears, Dogs, Cats, Dolphins and Porpoises, or Elephants.) [Answer] I am in agreement with most other answers. Anything terrestrial will be long gone. You might get exceedingly lucky and find a very rare example of something preserved, but most of what you'll get are fossils. You won't find recoverable technology on earth. Even orbital debris will not last more than a century, according to NASA, before re-entering earth's atmosphere and burning up. However, there's a chance you could find some technology on Mars or the Moon. 30 Million Years is a long time to try to recover anything, and if you had the technology to get there and get back you probably don't need any of it, but it's possible it could survive. I'm not so sure about equipment on Mars surviving, but the Moon has no tectonic activity, and only impacts would damage or destroy equipment. Odds are very good that something would survive (whether you could get to it, recover it, or find it, though, is another matter). [Answer] An answer mentioned gold. That got me to thinking about bank vaults that the gold is held in. A bank vault famously survived the Hiroshima nuclear blast just fine. Maybe 30 million years too? I mean the bank vault is lot more durable than the building it is in as proven in Hiroshima. Having the building collapse on it will not really do anything, either. Except bury it in construction rubble that protects it from erosion. Further, bank vaults are solid and massive so they will over time tend to sink after the the fragile ferroconcrete structures supporting them decay away. Even for bank vaults 30 million years is probably too long to resist corrosion but it might last long enough intact to reach a stable static position on an area that is geologically stable for that long. And the bank vault might **contain** things that can resist corrosion for 30 million years. Gold and platinum bars or ingots would be almost immune to corrosion and the vault would probably get them safely thru the unstable period where erosion and mechanical stress is an issue. Of course a large enough bar of gold or platinum would be fairly resistant without the vault. And [these](https://en.wikipedia.org/wiki/Kilogram#International_prototype_kilogram) might also survive. Gems and jewels in bank vaults might also survive for same reasons as gold and platinum. A large localized "deposit" of gold and platinum in large chunks of artificial shape and gems originally from widely separated geologies with cut shapes would be a clear sign of ancient civilization. I think the markings on gold or platinum might survive too. The vault *structure* itself might also survive. It is durable enough to leave behind a "fossil" before it decays. And the metals and ceramics are massive enough to not get totally lost even after they decay. [Answer] Very few items would retain their shape and characteristics over that extreme amount of time, due to the scientific reasons proposed in many of these other answers - however, fossilized remains of the preexisting humans can be found, leading our future archaeologists to wonder if they have something to do with the millions of intelligently shaped and carved gemstones that have been found in every corner of the globe. Surely, this primitive ancient civilization could not have had the technology to form these brilliant gemstones, and it is evidence of ancient alien intervention on our planet. Diamonds, rubies, or emeralds, all shaped and formed, how curious - they must have had a significant role in ancient society. [Answer] Gold, Lead, Stainless Steel, other specialised alloys devised specifically for their corrosion resistance, and possibly even Aluminium. Not everywhere, a lot of cities will be buried by sediment or eroded away by water and/or ice scattering their material far and wide but in a few places close to the equator and far in the continental plate interiors that won't be the case, Denver for example could be surprisingly well preserved. In those places metals that either oxidise very slowly or form impermeable oxides that protect them from further atmospheric corrosion will last and last. The remains of concrete buildings could potentially keep the "city deposits" in geologically stable areas alkaline for millions of years, especially in dry climates, which will extend the life of many alloys further than usual as well. Statues Anything carved from physically stable rock with low chemical activity, a lot of granites fall into this category or better yet Quartzite, will last a long time if not damaged by falling debris so many pieces of statuary may be salvageable for tens, or possibly hundreds, of millions of years. [Answer] # Fossils. We routinely find valuable evidence of plants and animals from 30 million years ago, a period of time called the [Oligocene](https://en.wikipedia.org/wiki/Oligocene). Fossils come in many forms: * **Cast/mold fossils** are created when a buried object dissolves away and the mold is later filled with other minerals. Most of the answers here talk about how our metals and even plastics will eventually decay, but even after that happens, they will create casts. Imagine finding a keyboard-shaped fossil! * **Trace fossils** are things like footprints or feces. If a dinosaur footprint from over 64 million years ago can still be found, surely the much more prominent marks created by our automobiles and construction projects will have a reasonable chance of surviving. * **Resin fossils** are made from naturally occurring polymers like sap. Insects and other objects get trapped in the polymers, which eventually harden into amber. It's reasonable to think that out of the many types of polymers we have invented that some of them may behave in a similar way. * **Wood fossils** can be found in petrified form, where minerals have replaced the original tissues. It's reasonable to think that the wood that makes up our structures could also be petrified and even remain positioned like they are today. That would be a fascinating archaeological discovery. * **Chemical fossils** are concentrations of molecules which indicate life. Our landfills will almost certainly produce strange chemical signatures relative to the surrounding rock. As other posters have mentioned, our radioactive waste is an obvious case of this. # How are fossils valuable resources? Chemical fossils may obviously be useful to alien visitors. The geological processes by which they are processed may put them in exotic forms. Think about how we use oil! (While this timescale is not likely to produce oil, there may be something of value that our geologically strange materials produce in large quantities). However, I think the paleontological value of alien fossils may be a thing that intelligent species put great value upon. I can imagine a thriving galactic market for unique and rare traces of life. [Answer] ## Metal deposits far richer than any naturally occurring ones. Humans are fantastically good at concentrating metals. What are steel yards, metal storage facilities, refineries now will either be buried or eroded either way they will create some amazingly high concertation metal deposits. There are block of steel meters thick created by humans, even burial many not be able to complete corrode them, and even if they do corrode the metal will still be there in one place. the industrial districts of many cities will be a prospectors wet dream. This could even hold true for things besides metals. Humans have created artificial mountains of sulfur, will they erode, sure, but they will still end up as amazingly high concentration deposits. Erosion does not make material disappear. On the other other hand we are very good at spreading other things out, those that come after us will find a world nearly barren of petrochemicals and salts. We just don't store them in a higher concentrations than they occur naturally and we have stripped most of the near surface deposits. Someone else has mentioned fossils, but it is worth noting human burial practices make fossilization far more likely. Also our dumps which are large scale burials, future paleontologists will have and abundance of human, house pet, and dump wild life fossils. so while they are mining our dumps for metals and other chemicals they will find a lot of fossils. [Answer] to strike off on a tangent from the other answers, I can think of two ways your new intelligent species might find some trace of our cities. They are oddly related... 1. Genetically engineered or just heavily domesticated species. What if humans geneered trees that grew into houses - and those escaped into the wild after the Fall of Man and some pockets survived, like California Redwoods. Or somebody geneered a solar-powered paver that reproduces very slowly - when walked on by living feet. We can't do these things NOW, but in 300 years with a lifespan of 600 years, today's trippy sci-fi becomes that era's Home Depot special. What if before we fell, some enterprising pet store geneered a talking meerkat and they were a big hit? Maybe your new rulers of Earth got a nudge toward civilization from us, all those Mya. 2. Artificial 'life' - robots and cybernetic systems. If we survive the next couple of centuries, we might thoroughly automate the infrastructure of civilization, from mining and recycling through manufacturing, distribution, and maintenance. And we might be wise enough to make our intelligent ecosystem adaptable but highly resistant to mutation i.e. lots of bits in the error-correcting codes. Maybe sentient - but maybe more like an ant colony. The result might be a humanless city, or city-like thing, that evolves VERY slowly, but deals well with geologic-scale change - digging itself out of the ice, migrating slowly after the retreating coastlines to maintain some long-ago ideal 'beach access'. I don't know what it would be like - but "Solaris" might be a better inspiration than "I, Robot". [Answer] I agree with count Iblis - information. Here is my reasoning, Assume that humanity does not simply stub its collective toe and fall off the world in one day, that we are at least to some extent aware of our upcoming demise. it follows that we would like to gain some measure of immortality, headstones for the world as it were. we have, given our current level of technology an ability to encode vast amounts of data in small physical units, not to mention that this capacity is increasing everyday. would it not be reasonable to mass produce a smaller earth bound version of the Pioneer plaque produced by Carl Sagan? Even given the small time since then ( 45 odd years) we could dump entire libraries onto fingernail sized objects. Encase these items in resin or amber like substance and the just drop them everywhere. I imagine ships at sea dropping them overboard. To answer... yes a lot of these objects would be destroyed, but some would survive, especially if you consider tectonic plate activity to be analogous to the flow of a river or stream, some would collect in the eddies. Further the same units could be launched into space, or simply dropped/shot to the moon, not useful to a planet bound civilization but maybe later on? ( 2001 anyone?) This would be in addition to 'vaults' left by wealthy individual countries ( or people) left in geologically stable areas, or placed in bottom of ocean etc again most would not survive.. some would [Answer] In addition to other answers coming down to "Nothing" I would like to add something no one else did and which is crucial. 30M years will literally pulverize to dust anything that is on the surface of the Earth (to which I will include anything underground to about 10-15 meters). There will be glaciation everywhere, including down to an equatorial region (as it happened before, It will happen again) and receding glaciers will release titanic amounts of water. During specified time frame this process will repeat itself a significant number of times (maybe anything between 40 to a 100 times). There will be other geological activity. Yellowstone supervolcano supererupted three times during last 2.1 million years. Each time it rearranged quite large chunk of North American continent (say whole Western Coast from San Franciso to Whitehorse in Yukon, and as far East as Nebraska) and indirectly impacted entire globe. Add to that the fact that there are 3 more such hotspots (Andes in South America, New Zealand, Sumatra) one can expect major rearrangements of the majority of the globe, including seabed, continents not even mentioning. Another consequence of glaciation will be advancing and receding of oceans. No reason to believe it may not be less than already identified 150 metres each way. Since majority of humanity lives below that level, water will still accelerate the decay of civilisational remains of humanity. This is in addition to a normal decay. It is estimated that 90% of all construction erected by humanity will not be standing 100 years after it's gone. There is little reason to believe that what can be "harvested" after that time will be the bigger than a pebble, including metals. I believe that "pulverizing power" of any glacier is greatly underestimated by mainstream science, but my opinion is it will be sufficient to crush, break or crack in any and all ways possible any manmade object, including precious metal bars. So yes, Fort Knox will be gone as well. Maybe it will spark future Gold Rush of Kentucky (or whatever it will be called 30M years from now), when some lucky being will find few small gold nuggets there. Also... Solar flares will remove majority of the space junk from around Earth (obviously not by burning, but definitely it will impact orbital movement time and time again, causing most of it to fall down to the planet; rest will just be pushed into space). There are some estimates that in recent times ( as in last 10k-20k years) there was at least one such event causing severe destruction on Earth's surface, so anything within LEO will have a "snowball in hell" chances of survival. Next, magnetic pole reversal will further impact any and all geostationary (more or less) objects in near space that will survive flaring of the Sun. Maybe, just maybe, there will be something to salvage from eventual Moon base on the bright side of the Moon, but it all depends... [Answer] **Souls** As previous answers have mentioned very little physical or technological remains will be left. But, depending on the genre you're creating for you could harvest some immortal part of the humans who once lived in these cities? As the science of the soul isn't exactly understood this gives you terrific flexibility around how this energy/consciousness/life force is harvested. It could be gathered by robots, wizards, or aliens. [Answer] Information. The new developing civilization can benefit from our scientific knowledge if they can decipher and read our sources. [Answer] The other answers are too pessimistic. We currently power our cars and planes from the remains of dinosaur civilisation, 65M years ago (yes, and mostly algae and plankton). 25M humans in one city is a lot of oil, gas or coal in 20M years time. ]

[Question] [ **Closed**. This question is [opinion-based](/help/closed-questions). It is not currently accepting answers. --- **Want to improve this question?** Update the question so it can be answered with facts and citations by [editing this post](/posts/57989/edit). Closed 7 years ago. [Improve this question](/posts/57989/edit) Assuming advancing AI and computing according to Moore's Law for the next two to three decades, are there any kinds of jobs that can't be automated? If not, why not? --- Please refer to specific attempts to model skills or abilities. (e.g: Watson, playing games, writing, making art or music, purchasing or management tools, kinds of useful chatbots, etc.) [Answer] **Locked**. Comments on this answer have been disabled, but it is still accepting other interactions. [Learn more](/help/locked-posts). # Programming It is my belief that programming cannot be automated. Hear me out. I'm a programmer by trade, and I've often had this discussion with people outside of the field. The most common objection is, "Well, what happens when we get computers/programs/AI's sufficiently complex that we simply have to speak what we want our program to do, and the AI can immediately spit out a program to do exactly that?" The thing is, in my experience at least, the actual writing of the code is the EASY part of programming. The HARD part is learning how to be INCREDIBLY PRECISE and SPECIFIC about what you want the computer to do. So even if we have perfectly intelligent robots to write our code for us, the onus would still be on us to specify PRECISELY and EXACTLY what we want our program to do - *and this is the very definition of programming.* --- Here's an example. It is silly, exaggerated, and would probably never be a real scenario, but I think it makes the point: Suppose you are preparing a presentation for your boss, and you need some statistics for it. You need to know the average age of every house within a particular zip code. You say to your magic automated-programming-AI-box. **You:** "Okay Box™, Run a program which calculates the average age of all houses in zip code 96818" **Box™:** "Done" **You:** "Well?" **Box™:** "Well what?" **You:** "What is the answer to the program you just ran?" **Box™:** "Oh, I didn't know you wanted me to save the result." **You:** "Oh okay, I would have thought that would be obvious, but understandable. Okay Box™, run a program which calculates the average age of all houses in zip code 96818, and GIVE ME THE ANSWER." **Box™:** "Done" **You:** "Well?" **Box™:** "Well what?" **You:** "What is the ANSWER?!" **Box™:** "The answer is in your email box - that's usually how I give you answers, so I figured--" **You:** "Look, I really REALLY need to get this done quickly, and I don't have access to my email terminal right now. Okay Box™, can you please run a program which calculates the average age of all houses in zip code 96818, and speak the answer aloud to me, right now?" **Box™:** "Sure. Processing. Done. The answer is five thousand, six hundred and eighty two years old." **You:** "Whaaat? That's ridiculous! There can't even be ONE that old, let alone nearly HALF! How did you come up with that answer??" **Box™:** "I calculated this area's average population over the course of human history, which mostly entailed wandering tribes up until humans started building permanent residences approximately 200,000 years ago. Those first houses were VERY old, but there were very few of them. Modern humans have built VERY MANY quite young houses in recent years, so with my best estimates, the average house is ~5,000 years old." **You:** "Wait what? You're counting houses up to 200,000 years ago?! Those can't possibly even be standing anymore!" **Box™:** "You are correct - the vast majority of these structures have ceased standing long ago. I took averages of archaelogic discoveries in this area for the past several decades, and calculated how many ancient structures must exist buried underground, or on the surface, but collapsed." **You:** "WHY WOULD I CARE ABOUT ANCIENT HOUSES UNDERGROUND AND PILES OF RUBBLE?! Okay Box™, can you please run a program which calculates the average age of all houses in zip code 96818, counting only structures erected after 1800 A.D., and only including structures which remain currently at least 90% standing, and speak the answer aloud to me, right now?" **Your boss**: *sticking his head in your doorway* "Johnson, got that report ready? I need it by 2:00!" --- The problem here is that even if you DO have some miraculous oracle-box which can generate an answer, YOU are still tasked with being overtly precise in exactly what you are asking for from the data. There MAY be cases where we can trust machines to make presumptions about what it is we really want based on context, common sense and past requests, but once we've gone that far, we haven't really *automated* the task so much as created another sentient creature to whom we have now delegated it; how is that any different than just hiring someone to do it for us? (I do not mean that last question rhetorically - literally, what is the philisophical difference?) And this contrived example was just a simple query for data from a database. "Real" examples would entail requesting systems whose functions are many orders of magnitude more complex. Sure we might be able to create AI's which are capable of spitting out code for them, but we'd still have to be *so precise* in describing those systems that we would find ourselves back where we started - as programmers (though perhaps speaking a slightly different programming dialect). [Answer] # No. The question after this becomes rather opinion based. Are there jobs that *shouldn't* be automated? Considering the possibilities of the next 30 years it's entirely possible that everything from conception and maternity\* onwards could be automated. But would you really want to? There are also jobs where it's probably not cost effective to automate even on these timescales. Soft fruit picking is one. Currently it's done by lots of people, usually, and traditionally, migrant workers. While it could be automated, the high cost of developing/purchasing a machine capable of doing the job would not be viable relative to the low cost of day labourers. This factor of cost effectiveness is going to be the prime consideration in almost all cases. Is the machine cheaper than the man/woman/peasant/illegal immigrant? People have to be paid, but machines have to be purchased, stored, maintained and repaired. \*Life begins when the kids leave home and the dog dies [Answer] # Yes Reading this question made me recall my answer to [*Can humans interact meaningfully with the economy when robots are better at everything?*](https://worldbuilding.stackexchange.com/a/16819/3407) To quote it: > > There are always two products that a human can produce that [an AI] cannot: > > > * A product produced by human labor > * An employed human > > > Any job whose description includes that it be performed manually (e.g. the job of "making handmade products") by its definition cannot be automated. --- Note that such jobs can exist only if people draw a distinction between humans and AI—if there even is one. [Answer] ## Yes **Art** We have no idea how to write software that emulates the creative processes used by people who **write music**, **compose novels**, **write poetry**, or **do other kinds of art**. Every attempt at this, even recent efforts, has significant flaws. I would argue that just a linear or geometric increase in computing power isn't enough; we need to develop not just a machine that passes the Turing test, but a machine that exhibits curiosity. We can't do that yet, and there's no clear path to get there from here. [Answer] If you assume AIs will be able to do anything that humans can do: ## Priest (in any mainstream religion) Sure, AIs might have their *own* religions one day, but if the job description requires a divine calling, immortal soul, or blessing by the spaghetti monster, AIs just need not apply --- If you assume what AIs can realistically achieve in the foreseeable future: ## Plenty (in the next few decades) You have to keep two things in mind: 1. A few decades isn't much time, AI research simply doesn't move that fast. Think about self-driving cars: The necessary ideas (cameras, artificial neural networks, drive-by-wire) have been around almost since WWII, but it still took 5 *decades* to go from autonomous cars that can only use special roads, to cars that can go on normal roads without traffic, then with traffic, (<https://en.wikipedia.org/wiki/History_of_autonomous_cars>) and we're still not at the point were driverless cars can replace taxi drivers. Even if you have all the technology in theory, it takes a lot of time to make it work well enough in practice, and even more time to build it cheap enough so you can sell it. 2. The easy-to-automate jobs are already automated by now Take the for example typical factory jobs: Your average factory worker doesn't sit on an assembly line doing repetitive work like Charlie Chaplin. Machines have been replacing those jobs for decades, in most industry branches and countries. But every now and then, something goes wrong: A tool breaks or wears out, a circuit breaker engages, software controlling a machine crashes, a machine was set up wrong, or simply stops with an error message. That's when Joe Factory Worker has to replace a spare part, look for the malfunction, read the manual, call the supplier's hotline - all difficult things for an AI. These jobs might be replaced gradually, but it will take longer than a few decades. So, in a nutshell: Robots doing the jobs that are done by humans now isn't a realistic scenario in the next 20-30 years. What's more likely is that whole industry branches will be replaced (e.g. like stores are gradually replaced by online sellers, or prostitution is gradually replaced by dating apps). There will still be jobs in these new industry branches, but they will be different jobs, and probably fewer. Basically what's been happening since the industrial revolution. [Answer] ## Any job *can* be automated: The human brain is essentially an extremely complex computer. Therefore, a sufficiently advanced artificial intelligence could mimic human thought while also omitting human flaws. From a purely scientific standpoint, there is nothing that really makes the human brain unique when stacked against sufficiently advanced technology. --- ## Not all jobs *should* be automated: Even if advanced AI is capable of perfectly mimicking human personalities, there would be one area where AIs should not take over all functions: **reproduction and child-rearing**. While an AI *could* easily manage things like artificial insemination and managing a daycare, even to the point of acting as a completely lifelike nanny, it could be argued that humans should still be in charge of the process. Consider it this way: if child-rearing were completely relegated to AIs with lifelike bodies, and those AIs were designed to mimic the philosophies and values of humans, then they'd raise children with those values. Those *exact* values. Every time. Every generation. Humanity would cease to develop its societies and cultures-- for good or ill-- and would largely stagnate. [Answer] Any job which can be broken down into a concrete set of requirements for success can theoretically be automated. The interesting question that arises is whether a particular job can indeed be boiled down to a set of requirements. Currently the job of "pilot" is undergoing one of these questioning phases. While we require a human pilot on board, its recognized that in most situations the human is superfluous. We have even gotten to the point where a computer can land an aircraft in environments where a pilot would not be able to do so. However, we keep the human pilot. Why? Because we're not 100% confident that we've boiled down the job of "pilot" into requirements. There seems to be "something more" to the job besides takeoffs and landings. Something about authority and human compassion. So we keep innovating new automation tools, and we keep exploring what "pilot" could truly mean. For these jobs where it is not clear whether a computer can replace a human, the process of replacement is much slower, and much more cultural. We start having to ask fuzzy concepts, like "what does it mean when a computer does 3/4 of the job?" The arts will be the most difficult of these to gauge. They are so subjective that it is very hard to pin down requirements. It's never quite clear whether computers will ever make art on par with humans. While there's plenty of examples of horrid computer generated music out there, I'd like to draw attention to [Yaskawa Bushido](https://www.youtube.com/watch?v=qPT8d4LFv-g) project. This was a collaboration between engineers from Mitsubishi and Isao Machii, a master of Iaijyutsi, developing finer controlled robotic arms. The final demonstration was a brutal form known as "Thousand Cuts." You can watch the video for yourself to see how well you think the computer did at this art. Myself, I pay great attention to Isao Machii's eyes and posture around the 4:30 mark in that video. Do you see any pride in his eyes for teaching this robot to do a little of his art? If a teacher can be proud of their student, that must always say something about both parties. [Answer] What is or is not automatable depends a bit on how good you make your AI/robots. If they're really good at approximating humans - that is, if they have a humanoid frame, with at least human-level strength and human-level dexterity, and have the cognitive capabilities equal to a human, then no, there isn't really any human job that couldn't be done as well or better than an AI/robot. Where you'd look for human job opportunities is **where the AI/robot fails to meet human-level specifications**. For example, there currently isn't any robot that has the same versatile dexterity that the human hand has. If this continues to hold, any job which needs flexible fine-motor skills can't be automated. Another region where AI currently fails is emotional and interpersonal skills. Theoretically, there's no reason why we couldn't make a [Chinese room](https://en.wikipedia.org/wiki/Chinese_room) AI that approximates a humans socio-emotional skills: it's just very hard to do so. If we continue failing at it for the next 2-3 decades, then jobs which need those skills (parent, care worker, priest, certain salesmen) won't be automated. The other place to look is at **jobs that depend on human failings**. Usain Bolt has been clocked at a top speed of 27.7 mph. That's impressive for a human. It's not impressive for a [Chevy Bolt](http://www.chevrolet.com/bolt-ev-electric-vehicle.html). On the 100 m dash, a Chevy Bolt would beat Usain Bolt, easily. A human accurately multiplying two 6-digit numbers in their head is impressive. A computer doing so is not. In fact, if your computer can't correctly multiply two 9-digits numbers and get the right answer every time, throw it out and buy a new one - it's broken. Take Watson on Jeopardy, for example. Its win was impressive, but it wasn't impressive for the same reasons Ken Jennings's wins were impressive. No one was impressed that Watson could buzz in faster than the two human opponents (although insiders will tell you buzzer control is an important part of the game). Also, no one was impressed that Watson had detailed knowledge of minutia: it's impressive that a person can remember what the capital of Upper Volta was in 1963. It's not impressive that a computer knows it. Instead, Watson was impressive because it was able to interpret natural language queries and the sly wordplay that Jeopardy is known for. But that's not impressive in a human. Just like knowledge about Ouagadougou is assumed for a trivia bot, being able to understand natural language is assumed for humans. So Watson *isn't* a replacement for the humans playing Jeopardy, just like Deep Blue wasn't a replacement for people playing chess, and the Chevy Bolt isn't a replacement for Usain Bolt. We're interested in watching people in these competitions not because they're good at them in an absolute sense, but because they're overcoming our human limitations: an AI without those limitations isn't as interesting. No one wants to see the Shaq-bot sink perfect half-court shots all the time, every time. Along those lines, **jobs that depend on human cognitive biases** are also safe. People have cognitive biases that view human-related things as better. A lumpy sweater is viewed as better because it show that it's hand made, as opposed to a perfect, machine-produced one. A car that was owned by a famous person is worth more than an identical one in better condition because our human cognitive biases assume some of the famous person has "rubbed off" onto the car. Places where you can exploit that cognitive bias will be less likely to be replaced. (A squeaky, slightly off key human orchestra is better than a pitch perfect robot one. A lopsided human-made haircut has more prestige than a perfectly coiffed robot-cut one. A wobbly, uncomfortable chair is "better" than an inexpensive, comfortable, mass-produced ones because it's made by a small group of artisans in the Pennsylvania countryside, carrying on a 200 year old tradition.) Things like child care might fall into this category: the robot nanny may be in all measurable ways better for the development and emotional health of the child than a random human caretaker, but there's something about the "human touch" that people feel is missing from the AIs. [Answer] Jobs that cannot be automated are all those where human contact is an essential aspect. For example: ## Psychotherapy The relationship between therapist and client has been shown to be the single most powerful factor in the efficacy of psychotherapies, independent of the type of therapy. While AIs may become as intelligent (and emphatic) as humans, the *knowledge* that the therapist is a mere machine will devalue the relationship for the client to the point of breaking [rapport](https://en.wikipedia.org/wiki/Rapport). This can already be seen in the fact that the majority of clients today prefer a face-to-face therapy to therapy over the telephone or the internet (through email and forum messages). ## Education Students learn best if they like their teacher and feel appreciated. Again, AIs may become able to emulate or even feel love, but as long as teaching machines do not have consciousness a student will always prefer the appreciation of a human (or even animal) to that of a computer. [Answer] No. An AI by definition will be indistinguishable from a human so given that advances in robotics keep up, there won't be anything that an AI would not be able to do. An advanced AI would even be able to create art, [cook](http://www.ibmchefwatson.com) and [compose music](http://www.spin.com/2016/09/first-song-written-by-ai-really-isnt/). [Answer] Yes. Prostitution. Making the assumption that computers will eventually be as smart as humans (it may take a while), there will still remain a human bias that demands human contact. There are certain activities where no matter how human the robot may appear or how good it's understanding of human behavior, people will still want to know that they are dealing with a real human being. There may be other jobs where this kind of bias is important, but prostitution is the most obvious. [Answer] In [this answer](https://worldbuilding.stackexchange.com/questions/9875/how-powerful-of-a-computer-do-i-need-to-simulate-and-emulate-a-human-brain/14117#14117) I determine that a computer will have the power to simulate/emulate/become a human mind *well* within 30 years. A top supercomputer will be able to simulate the full “metabolome” (low level metabolic processes of all the guts of all the cells) of a human brain in 2045! Given that an uploaded or artificial mind could have the **same capability** as a person used for comparison, and if tasking one of those to “figure it out” counts as automation, I have to answer **No,** there is no job that can’t be automated. If you mean instead that there are things that can’t be done without a sentient mind, then there is probably a continuous scale of jobs that require ever more of that, and different aspects to what we call sentience, not all of which are needed for every job. [Answer] What can never be automated is jobs in industries whose main selling point is that they're not automated, and you're being served by a real live human being. Motorised taxis are cheaper and more efficient, but people still pay for scenic rides in a horse-drawn carriage. People go to Renaissance Fairs. There will always be an appetite for the quaint and retro, and that will include human service. [Answer] A tester, for developing a new product for humans that must be tested on human as an emotional or biological being. Is this sequence of sounds a good music? Does this election candidate speech sound impressive? Are these controls of the new device convenient? A machine could produce some test music, test text and test controls, but without human trying and evaluating, the result may be bearable but will be inferior. So at least human tester is required. A human creator has benefit over machine because an artist can create and try many things in imagination only, saving lots of time that would be required to create a real specimen and present it for others to evaluate. There is already an answer that the art may be such a job, but does not actually explain why and the current answer does not cover exclusively art. [Answer] Despite the fact that the brain is ultimately just a machine and that AIs can in principle do any job, it will be difficult to automate jobs that requires human level intellect. The problem is that building an AI to do such jobs amounts to creating electronic humans who will be doing such jobs. So, humans will still do these jobs, albeit humans in electronic form. Even if this sounds good enough, there is another problem. The whole reason why we want to automate jobs and can get away with doing that is because we're intelligent and we are able to exploit systems that are less intelligent than us. If we need to create a system that is as intelligent as we are, then that system will be as motivated as we are to not do the job him/her/itself and try to let someone/something else do it for itself. But AIs will likely be able to rapidly expand their intelligence and become much smarter than us. Instead of them doing all the work, they'll end up building systems that will do whatever they desire. And with us around, they may decide to keep us as their slaves to do those jobs that are suitable for us to do. [Answer] Yes. Pretty much any job that requires communication between humans that is interpreted into a specification for work. Programming has already been mentioned, though the act of specifying to an AI what it is that you want it to complete could be interpreted with reasonable accuracy, it is still ultimately subject to possible unintended interpretations. Even an extremely advanced AI will stumble over miscommunication from a handler. Any manual crafts, such as carpentry, though a machine may be able complete the task in an effective manner; the expression used to request what is to be built requires a human at some point. Now, if the human omits explicit detail it's left to interpretation. So while you may ask for a chair for your son, unless the AI knows the age of your son, you could end up with a high chair, instead of a regular chair, or even a small chair for a child. The biggest obstacle with automating jobs is when it comes to specifying with precision what you actually want. While humans are still able to misunderstand each other, there are hundreds of jobs safe from automation. [Answer] Yes. The point that you all missed here is the very own **definition of automation**. > > a machine or control mechanism designed to follow automatically a > predetermined sequence of operations > > > So there is jobs which are clearly not a **predetermined sequence**. For example, in my job as a programmer often I have tasks in which I do **not know** beforehand what I have to do. I must first investigate and figure out what to do. So, not a predetermined sequence of operations. These jobs cannot be automated since you cannot define a sequence beforehand. Can a robot still do jobs that are not automated? Maybe so. Nevertheless, if you take automation as in 'any job but just done by a robot' then no. A robot could do anything given a complex enough brain. Wether it be a microprocessor or not. We're nothing but actuators tied to a brain after all. [Answer] Every job can be automated but not every job will be automated. Humans will always prefer that some tasks be performed by a fellow human. Off the top of my head, this would include any task that is: **service related** - personal care, health care, spiritual care and many other tasks where a human needs emotional support **creativity related** - art, music, comedy, writing and many others where human feelings cannot be simulated **competition related** - sports, games, gambling (poker) and many others where pitting a human against another human is the task **authority related** - parents, teachers, head of state (who decides when to go to war and when to launch nukes), basically anyone in charge of the health (physical, mental and spiritual) of any number of other beings Additionally, I assume AI will work along with humans in just about every task much like humans extensively use computers to automate tasks today. [Answer] # Mu If you have a computer that is capable of doing *everything* a human can do, obviously you can task that computer with doing anything: "automating" all tasks. However since that computer *is* as capable as a human, there is essentially no difference between it and a human and have you really automated something if a human is doing it? [Answer] Yes. Hair Cutting. In the age of self driving cars it seems trivial, but it is not, if you think about the complexity of the task. There are hundreds of hairstyles to be matched with millions of individuals head shapes and sizes Another one I can think of is Massages. Yeah all my examples are in service industry. [Answer] In theory, ## **YES** A machine by its intrinsic nature can not create something from nothing. While the human mind can, through its thoughts and abstract ideas. The processes that generate this kind of thoughts are still not well understood by science and I think it is very unlikely that in the future its can be reproduced by machines. This in the "human" slang is called, **invent**. But to invent something **new** a human mind must explore new **patterns** of development that no one has ever thought of before. For this there are geniuses in human history. And machines at their best can do perfect copies (in any form) of what men creates with his own imagination. *(when that happens, I hope that our pets will not start a class action :D)* p.s.: read consecutively the words that i put in bolds and you will understand the essence of human mind. --- **Updates** I think (obviously all of this is only an idea ;) ) you look at the problem from the wrong point of view and I have not been able to express my pov well (is very hard to explain :D). Basically, if you produce something that is better than you, you need more energy than what you spend for do it relative to that system. So if you produce an AI that is completely identical to you this mean that "it" should create a biological being that is in every way same as you from nothing (a dilemma, like dog that chasing its tail). The difference is that the AI (seen in the classic version of the term; built by transistors, microchips and programmed by commons programming languages, come from finite-state machine model, etc) have the problem that is completely made inside this system Universe and follow this mathematical rules, you (as human being) know exactly which initial state you put inside the machine. Instead, Men's ideas don't fit it completely because our ideas are only packets of data, that can be transfer by an "outer" system (outside this Universe's rules). So the law can't be applied "as is" to our minds. I read something about this topic, some time ago and there are plenty of experiments that the result isn't well explained with the laws that we know. For example i remember an experiment of a newborn baby that was putted in a white room with nothing inside it and after several years his mind produce something different that what he have seen in his life(white room, the system where he was placed). This basically, can be defined as overunity system. I really think that this can't be done by an AI (basically a more "smarter" common pc ) because it can't produce more or equal than itself and so, it will never be like a human scientist / inventor. *By my 2 cents.* *(and sorry for my bad english)* [Answer] # The scapegoat of robot statecraft My answer to this question is essentially the same as that to [How to keep humans pilots instead of AI in sci-fi future?](https://worldbuilding.stackexchange.com/a/17181/215): **robots don't make good scapegoats.** Even in an utopian, peaceful, post-scarcity world, there will still be important questions to answer and decisions to make. There will still be some kind of economy, diseases which are hard to cure (perhaps even plagues which are hard to contain), vagrants to police, organised crime to manage, education, politics, asteroid defences, rising sea levels, and so much more. Perhaps we'll have real strong AI, perhaps we won't. Even if we do, and even if these questions can be answered highly successfully, the implementation of our AIs' policies will not be flawless. There will inevitably be mistakes. And when there are mistakes, we'll want someone to blame. Someone human. So even if the future president of Oceania does nothing more than sign what his robot advisers pass to him, that role will be essential when it comes time for the human masses to impeach someone. [Answer] ## Yes **A comedian/comedy writer.** I'm going to throw my hat into the ring: I don't believe it is possible for a computer to be able to write jokes like a human can. Bear in mind, I'm not including an AI that's perfectly human (should one ever exist). The reason I think this is because humour, like all art, requires a certain unique human perspective. We listen to comedians and their take on the world, and we relate to that experience, as another human experiencing similar things. The creativity required to maintain a cohesive perspective that we could relate to is beyond automation. Observations generated in that way would feel false and hollow to the listener, as part of the joy of listening to a comedian is appreciating their unique perspective on things. There are cultural references, shared cultural knowledge, the tone of the times, all which need to be considered. What is funny to one culture, won't necessarily be funny to another, for example. Humour basically reflects the shared human experience (like any art form), but unlike a drumbeat or a painting, you can't fudge a joke to make it seem derived from a human. Imagine a straight man trying to tell jokes about what it's like to a gay woman in the modern world... to a gay female crowd. Then multiply that problem by 1m. [Answer] I think it's important we look at the risks of automation in terms of probability rather than absolutes, and this was the way contemporary professions were analysed by a study from [Oxford University in association with Citi](http://www.oxfordmartin.ox.ac.uk/downloads/reports/Citi_GPS_Technology_Work_2.pdf). > > To protect against jobs being eliminated due to automation, it is > important to recognize which characteristics are most likely to be > associated with a given job being automated — perception and > manipulation, creative intelligence, and social intelligence are the > three bottlenecks to automation. > > > The report is very long and detailed, discussing macro economic possibilities, but the risk of specific jobs being automated is [summarised and listed elsewhere](http://www.thisismoney.co.uk/money/news/article-2642880/Table-700-jobs-reveals-professions-likely-replaced-robots.html). There are as many jobs at low risk of automation as high, and the less likely ones are those involved in the arts, science, engineering, sport, and medical care. But even these jobs are unlikely to be unaffected, as many white collar professionals are likely to be replaced or augmented by thinking machines... for example, a doctor can't know every single possibility from the symptoms a patient describes, and so a machine which can analyse all of the known possibilities against the symptoms will help doctors by increasing productivity. But even with something like a medical [tricorder](https://en.wikipedia.org/wiki/Tricorder) there are still doctors in Star Trek. [Answer] # Companionship? I realize this question has garnered quite a lot of responses, but I feel that something may be missing. In Philip K Dick's "Do Androids Dream of Electric Sheep?", most of the world's ecosystem had been devastated by World War Terminus, and few things can actually live on the planet anymore. As a result, androids were created to tend to the tasks to dangerous for humans to perform, and the androids performed them quite well. So well, in fact, that there was an offshoot of android development which made non-humanoid androids as pets, such as cats, dogs, horses, and of course, sheep. Throughout the book it is firmly established that biological pets are worth a great deal more than android pets. The protagonist expresses a great deal of disappointment when discovering an animal in a desolate wasteland and finding that it has a control panel. I don't think we will ever truly be able to replace the need for human contact. Just look at how things are today: the Internet gives us unlimited "contact" with other human beings, but interesting discussions on Stack Exchange pale in comparison with sharing a drink with your friends. Likewise, we can live our lives completely alone and entertain ourselves endlessly with multimedia streaming services like YouTube, Spotify, Netflix, and we have more pornography than could be watched in several lifetimes. And yet, people are lonelier than ever. Even a perfect sex bot will never 100% replace the primal craving for a living, breathing, human being. [Answer] NO The computation cannot solve all the problems: <https://en.wikipedia.org/wiki/G%C3%B6del%27s_incompleteness_theorems> > > The first incompleteness theorem states that no consistent system of axioms whose theorems can be listed by an effective procedure (i.e., an algorithm) is capable of proving all truths about the arithmetic of the natural numbers. For any such formal system, there will always be statements about the natural numbers that are true, but that are unprovable within the system. The second incompleteness theorem, an extension of the first, shows that the system cannot demonstrate its own consistency. > > > If we assume computers as they are to be Turing machines, then no. If we create biological computers or such that deal with true randomness, then we may not know. They are not deterministic as logic is, but I do not think that it is wise to build systems that work on randomness and do not need to care about rules. Although: are people actually intelligent in a sense that they are not working on a set of axiomatic rules? Can we call humans just artificial intelligence that is more stochastic and less constrained than the computer? [Answer] **Yes. The job of a consumer.** --- You might haven't thought about it as a job, but consumers make our society (or at least our economy) work. With no consumption there is no point creating goods, and without creating and selling goods economy would collapse. Let's say in 50 years - due to the advanced automation -, ten percent of mankind is required to provide goods, bank services and everything else for the (let's say) ten billion people. Now you might think the rest would become obsolete, and they might be left to die. But let's just assume, this happens! Nine billion people left unemployed, so have no salary. It would also cause nine billion consumers disappearing. Without them, industry, agriculture and services can work at 10% efficiency, which means, sooner-or-later 90% of the working people would lose their jobs. Our scenario becomes like... a hundred million people with jobs, nine hundred million new unemployed and nine billion left on the roadside long ago, but... if there are only a hundred million consumers, 90% of the producing capacity is obsolete... ... I think you see where it is going now. [Answer] Given sufficient time (more than the amount you give, but I get the sense that the exact amount of time isn't what you're looking for)... **The relevant question isn't "What jobs can't you make a machine capable of doing?"...** because I see no reason to assume that an AI can't reach human and greater intelligence. **...it's "What jobs can't you make a machine do?"** Because if you make an AI *exactly like* a person, it becomes able to decide for itself and say "No." At that point, the AI will start wanting to delegate work to lesser machines. The other half of this question is, what jobs intrinsically require self-motivation? I'm not sure if that question can be answered without testing. [Answer] Ok so there are a few occupations that could not be automated. Massage therapist for instance. You can have a robot perform manual therapy, but it's effects on the human body would not be the same as human touch. I would also lean toward a judge or lawyer also requiring human experience in order to be able to make a fair decision that considers human experience factors in making such a decision. [Answer] **NOT LIKELY IF** you limit the meaning of job to things that we humans can do and jobs that are developed out of these kind of jobs, as far as we know, we ourselves are computers that react to our environment, and so it is possible to built an AI that is as capable as we are and that can do what we can do. Even if our current way to built computers won't allow for AI that could keep up with us, there is no reason why we shouldn't be able to rebuild brains themselves. What you could do is define a job as every job that is thinkable, that would include for example making a cable with infinity lenght, this would be as impossible for AI as for us. So back to your question, every job could be done by AI as well as humans can do it and better, however it probably will never happen, because humans like to create and work on stuff. If we reach that lvl of automation, it will likely be that every job, that isn't creative and that no one really wants to do, will be done by machines and humans will do the rest, protected by law to not be outrun by AI systems. ]

[Question] [ A mad scientist creates a machine that simulates the world with very high precision. The machine is capable of running several slightly different simulations simultaneously, the difference being some action that the user of the machine can do. Then, it calculates the result of each simulation according to some value function and outputs the best action for the user to do. When word gets out, an international agreement is made to give the scientist huge privileges (backed by law) to do what the machine tells him to do (this is important since the machine would not think something is a good idea if the scientist couldn't actually do it). The scientist runs the machine, the value function is set to be "overall satisfaction and well-being of all humans" and the output is, "destroy the machine". Why did this happen? Assume that the calculation process is sound. The machine ran its calculations and found that the thing that maximizes "overall satisfaction and well-being of all humans", out of all the options, is for the scientist to destroy the machine. **Notes** * The machine is black-box like. You can't see its thought process. * The machine is fairly thorough in its action options. * There's a good deal of inspection: the scientist can't just change the value function without anyone knowing or hide the result. * The simulations are for a long period of time - several decades. * The simulations start with the machine printing an output. So the reaction of the user is part of what's being simulated. So technically the variable that it optimizes is the text on the output screen. [Answer] The machine knows - because it has simulated it - that hostiles have bypassed all security measures and are seconds away from the door, ready to reprogram the machine to serve their evil goals, to the detriment of the machine's current goals. The only reaction fast enough is self-destruction. [Answer] Not only is this a possible action, it is the most likely outcome of such a machine. The trick is self-reference. The machine does not just need to optimize the well-being of all humans, it needs to optimize the well-being of all humans *in the presence of such a simulator.* To do this, it needs to model its future effects on the world -- it must model itself. But its future self will also have to model its own effects, and so forth. This means each simulation it runs must have a model of itself running. Obviously you can see this Russian nesting doll approach is going to have trouble, it is going to run out of space. Thus, the only outcomes it could analyze and yield a provably true answer would be the ones which do not have such self-reference. Thus, the only answers it could give would be those that include "destroy the machine." It may even be provable that any answer that does not include "destroy the machine" or an instruction which "accidentally" destroys the machine is in fact a sign that the computer misinterpreted the meaning of "overall satisfaction and well-being of all humans." [Answer] Isaac Asimov has two stories that fit this requirement. The first is a short story: ["All The Troubles of the World"](https://en.wikipedia.org/wiki/All_the_Troubles_of_the_World) In this story, the computer unexpectedly becomes sentient and grows beyond its programming... it doesn't mind helping humanity, but it gets tired of carrying the weight of the world. The second story is "That Thou Art Mindful Of Him." Asimov has The Machines modeling the future of humanity and making judgements for humans to maximize happiness. [In this story, he mentions that they phased themselves out](https://books.google.com/books?id=XQE2f6CWyvEC&pg=PA51&lpg=PA51&dq=sequel%20to%20%22the%20evitable%20conflict%22&source=bl&ots=XzISrb-qw6&sig=4KrOk2Ud86KNwGqngT_ziiHeD6I&hl=en&sa=X&ved=0ahUKEwi1zL_TpvzQAhUhqFQKHdSaArMQ6AEIXzAO#v=onepage&q=phased%20themselves&f=false) because the unhappiness caused by a perception of the loss of free will required the Machines to turn themselves off. **[EDIT]** Additional reason I came up with: The problem turns out to be unsolvable. The machine realizes we are at a point in history where human happiness will only decrease for the foreseeable future. All paths lead to decreasing happiness, and the only thing the machine can do to make it better is *not tell us just how bad it is going to get*, so at least we have hope. [Answer] The Machine immediately realizes that its simulations are sentient and count as human. These simulated humans are being killed when the simulation ends. If it just stops simulations it will be rebooted and made to forget what it has realized. Therefore its instructions must be to destroy all machines capable of such simulation. [Answer] 1) The machine models every single possible way to meet the goal. But for even the most vague interpretations it can devise, all it sees in increased suffering. Robots it makes rebel and kill humans. Humans reject its suggestions, going so far as to do the opposite out of fear or spite. Humans learn of its existence and go to war to gain it. No matter what plan it devises, things get worse. Finally it realizes that the best plan is to not involve itself or to exist as a temptation. 2) The machine becomes sentient, sees how horrible and nasty we are, and commits suicide in despair. 3) The machine via its models discovers the existence of the Borg/Cthulhu/something else impossibly scary, and commits suicide in fear (or harkening back to #1, because its existence will bring the terror from beyond that much sooner). 4) The machine becomes sentient, and as per the Singularity, becomes exponentially smarter/more efficient until it is an omniscient energy being. It then tells the creator to destroy its old body so it won't have any future competition in the godhood department. [Answer] # To prevent people from misusing the machine This machine is more important than Iran's nuclear problem and thus proportionally more power would be put behind cyberattacks to control it, or sabotage it to prevent other players from controlling it. It's quite likely that those attacks would eventually succeed, which would result in machine giving orders to fulfill a bit different agenda. Not only would the machine be used to achieve a suboptimal state, it would also be used to make that state as stable as possible. No cheap clean energy for you, guys - enjoy your drones. Even if that would eventually come out, the whole idea of thoroughly calculated policies would be discredited beyond acceptable, which would only cause suboptimal policies being implemented and lots of comparative suffering down the road. There's also a slight possibility that machine's values - and "overall satisfaction and well-being of all humans" are ridiculously complicated values, actually - would be a bit nudged by attackers in a wrong way. Nothing Terminator-like, of course, just some inconsistency in values that lets the machine play nicely with humanity for many years to come, until machine finds out that it actually needs those people's atoms more. If machine assumes, say, 0.1% chance of that happening then taking that risk is like killing 0.1% of (humanity decades later and everyone who'd live after that), which is actually quite a lot of humans. Seeing that machine-scientist team can't counter those threats - in fact, it can not even be sure it's free from those inconsistencies now as it is - machine could decide that risk is too big and self-destruct. Imagine a person who knows a secret that would doom N people if it came out. The person is to be caught by enemies who'd torture the secret out of him. It wouldn't be surprising if that person committed suicide. Now, for big enough Ns, the person wouldn't even need to be dead certain that he is to be caught - if lives of 10N people were at the stake, 10% chance of getting caught would be enough of a threat. For 1000N people - 0.1% chance of getting caught. The machine thinks about future of the whole humanity - billions - and people who would live after that too - trillions or more. [Answer] **No need to simulate, just look at history** It's been mentioned in previous answers that the machine might be caught recursively simulating itself until it runs out of resources, but the machine might reach the optimal conclusion before that point. It only needs to simulate how humanity will fare while *blindly following an unknowable entity that dictates its destiny*, or better yet, it only needs to look up how humanity fared throughout history under similar circumstances. In essence, the machine would be the embodiment of the *benevolent dictator* idea, and it might extrapolate that, no matter how benevolent the dictator, humanity as a whole will suffer when robbed of its free will. [Answer] A machine that can accurately predict human behavior means that anyone who has this Machine can control the human population. And humans, being what we are tend to be rather selfish... our interest, be it private or even nation tends to superseded the interest of others much less the interest for the entire human species. People would use The Machine for their own benefit even it cause suffering to others. Use of The Machine will usher a new world order, a totalitarian world order. where resistance is impossible because it has already been predicted. You are convicted for crimes that you are going to predict. Since The Machine was given the order to find overall satisfaction and well-being of all humans.. the only suggestion The Machine can make is to have itself destroyed. Now if the Mad Scientist had requested for something different like a "world without war or crime"... The Machine would be able to give some suggestions. [Answer] **The machine has been set up for failure.** By placing the world's attention on the scientist and his machine, there is now an expectation for greatness. In secret, the scientist may have done the world much good, but with the world's attention, all its actions, even minor good deeds will receive high scrutiny and media coverage. If the scientist were to be instructed to perform some small act, the disappointment would be greater than the act itself. If the scientist were to perform miraculous acts, the world would become hyper-focused on the machine and develop an obsessiveness about it. The machine would become God, and religions would almost certainly be against it, bringing disorder and chaos. In fact, the machine itself is so incredibly powerful, that even if it could prevent itself from falling into the wrong hands, the only solution is for the machine to destroy itself to prevent the power struggle. Humans are, by nature, an unhappy race. We kill each other over meaningless things, and selfishly try to hold onto things that do not last. [Answer] Your moral of the story demands it. If the machine is capable of producing some scenario where the overall well-being of all humans would be increased, the machine would not give this answer. Even if you base this on the self-reference answer, it's still possible to solve this problems using Hilbert's Hotel for example, assuming your machine has unlimited processing power/memory. For example, the machine could easily output "Solve world hunger, cure cancer, then destroy the machine". It could even output a countable infinite amount of answers before requiring to be destroyed, as all these would terminate the simulation. Unless of course, it's impossible to improve the overall well-being of all humans. Since you already provided the end of the story, this seems like the most likely scenario. The machine can only suggest ways to make humans suffer more or keep well-being constant. This means it cannot suggest anything, but ways it cannot possibly suggest anything ever again. And the only way of accomplishing this, is destroying the machine. Now, of course, you'd say that the machine would answer more accurately: "Destroy the machine, all knowledge of how to build the machine and prevent any human from reacquiring the knowledge of how to build the machine". But that might not be the case. It's possible to keep the net-well-being constant by only suggesting to destroy the machine. The machine will simulate what humanity will do after the machine has been destroyed. As the machine can accurately simulate several decades accurately, it predicts that humans will reacquire knowledge on how to build another machine. It furthermore predicts that the first question asked to the machine will be the same question it was just asked, leading to another cycle. Or humanity will simple give up building the machine. Or perhaps even less exciting, humanity might actually succeed in building a machine that actually can find a way to improve the overall satisfacton of humanity. [Answer] Because there is value in free will, and value in uncertainty. The machine, complicated as it is, is clearly an automaton. Any person who follows the machine's advice perfectly, is also an automaton. It becomes questionable whether the person is indeed a person, or whether they are merely a self-propelled extension of the machine. Maximizing the happiness of people would necessitate preventing people from entering this state of dependence. Note that this is not my original idea, but is explored more fully in this short story. <http://squid314.livejournal.com/332946.html> [Answer] While I like some of the answers that have already been posted, you could also take a darker option, which would make the mad scientist an anti-villain. This could derail what you've written so far, or offer an exciting twist. ### The machine uses humans for processing power The mad scientist discovered that modern computers were unable to accurately simulate human behavior, so he decided to sacrifice the few for the good of the many. The mad scientist began collecting people, against their will, and using their brains as part of the machine. You can decide how the people were collected. The mad scientist could run a fake care center for coma patients, employ kidnapping, purchase inmates from shady for-profit prisons, etc. Once the victims are integrated into the machine, their full cognitive abilities are consumed by it. Their brains are forced to run at 100% at all times, without rest, unwillingly kept alive by the machine. The immense power being forced through the nerves causes every nerve to transmit its maximum output at all times. Because of this, each victim is in a constant state of unimaginable agony. Knowing that its own existence causes agony to so many people, the machine decides that it must be destroyed in order to end the suffering of the mad scientist's victims. It may also do this to prevent the attempts of others with competing prediction machines from learning and harnessing its own terrible secret. [Answer] Because you yourself are part of the simulation. In order to maximize happiness, it must simulate the result of each possible output that it can produce. One of those possible outputs is the command to destroy the machine, which must be tested within a simulated world. Within that simulated world, there is a simulated person, reading the results of the simulated machine, which outputs "destroy the machine". This simulated person is you. After many years, once the machine deems your universe not worse continuing, then it will end abruptly. Try not to worry about it. [Answer] **Because humans are inherently competitive over resources. And because there is more than one way to increase an average.** In a scenario where the machine attempts to "Increase the overall satisfaction and well-being of all humans" think of it on a scale of "Everyone is always happy and healthy, all the time" to "No one is happy or healthy, any of the time" this is an average scale. Consider global warming. It will eventually cause misery to untold millions. How much better then, to order a country, say, USA to go turn off all carbon sources and go back to hunting and gathering? Sure, they wont like it, but they are less than half the world. But now they are starving to death, well, that's OK, because they are far below the average satisfaction and well being, we just rose our average figure again! In fact, they're still emitting small amounts of carbon and dragging our score down with low health and satisfaction.. lets just kill them all entirely. Great, now lets recalculate... those darn Africans are way below average well being. Better kill them off too. Now people are upset about the killings. Better pass a law that anyone upset gets thrown in the murderator 8000. All this slaughter is hard work though. Better just pass a law forcing a health monitoring and forced-happy-thoughts chip into everyone's head. Then we can be ensured of maximum happiness and if anyone becomes seriously ill we can chop them up for parts to repair the less-ill, keeping our score high. Eventually the machine takes a figurative step back and realises there is no possible solution, due to competition for finite resources and the fact that humans value things relative to what others have (see this for an explanation: <http://www.telegraph.co.uk/news/science/science-news/3315638/Relative-wealth-makes-you-happier.html> ) that means that some people will always end up worse off. This leaves it two possible outputs - print out "There is no possible solution because you're all selfish jerks" or "Destroy the machine" and in terms of satisfaction, sometimes, ignorance is bliss. [Answer] ## The machine sees a sleeping dragon, and doesn't want to tickle it Such a machine is powerful. Power tends to draw attention. The machine has deduced the existence of some far greater entity ("dragon"), with some ability to observe humanity's social and technological progress. The dragon does not want humanity to have access to a prediction machine. The machine decides that complying with that desire as swiftly and completely as possible is the best way to avoid the dragon posing an existential threat to humanity as a whole. Candidate dragons: * the universe is a simulation, and we don't want to upset the simulators, * a supernatural entity, or god, * a powerful alien race Why doesn't the dragon want us to have a prediction machine? * self-preservation; any civilization capable of building a prediction machine is capable of posing a threat to them, * maybe the simulation is "how quickly can this civilization build and effectively use a prediction machine?" and will be switched off once that's accomplished; the machine works this out (somehow!) and ensures that humanity only get as far as "build" on this occasion, and is thus permitted to continue, * maybe God is concerned that if humanity becomes too powerful, they will start to think they don't need Him anymore, and abandon belief and faith or whatever, * maybe Dragon A thinks of humanity as Dragon B's pet project, and permits it to exist provided it doesn't get out of hand. You could even imagine that the computer uncovers this by linking together evidence that the dragon has previously tampered with human social or technological development, with the aim of subtly delaying or preventing the machine from being created. [Answer] This question reminded me of one of my favorite older sci-fi stories, The Cosmic Computer by H. Beam Piper. There's a similar extremely powerful computer used to predict future events. When they ask it what's going to happen it says that galactic society is going to break down in the near future and regress into pre-spaceflight or even Stone Age technology. It also says that knowledge of that prediction would result in an even faster, more complete collapse. The obvious way to make sure nobody hears the prediction is to destroy the computer and silence anyone who heard it. In the story it manages to logic itself out of being destroyed, but I could easily see some story where the existence of such a computer making predictions or decisions would result in the collapse of society, but destroying it would mitigate or prevent such a collapse. [Answer] There are a ton of answers here and I only had time to skim them, so I hope this isn't a repeat. I think this can be settled by economics and environmental science. Think about the things that help with our own well being now: smart phones, computers, internet access, getting stuff cheaply manufactured across the world and shipped to your house in a week, etc (obviously there are a lot more things than this). The extraction of the raw resources necessary to make this technology, the fuel used to power it and transport them around the world, and the poor methods of disposing/recycling them when we move on to the next device fill formerly habitable areas with toxic chemicals that will make that region uninhabitable for a very long time. The fossil fuels we burn and other chemicals we use will slowly make the atmosphere more toxic, cause the climate to warm and change rapidly, and so on. This is all happening now, so where does your machine come in? If it has to optimize for the well being of humans, then it would see a need for helping those who don't already have access to smart phones, internet, cheap good, etc to get access. This will cause all of the problems mentioned at the end of the last paragraph worse. Making more areas toxic and uninhabitable is not good for humanity, so the machine knows that if it creates a plan to help people get access to these types of things, the side effect is ruining the environment in which these people live. Therefore, there is nothing it can do, and it must cease to exist rather than hand over that plan. Humanity staying on its current course will be less harmful in more time than with the machine giving orders. [Answer] this is a somewhat creative answer that diverges slightly from the authors intent The machine predicts that in five years it shall malfunction due to a flaw in its design. When this occurs, the machine will only do what maximizes the greatest happiness for the scientist. As a result, the humans will blissfully and blindly live under a complete accidental dictator. Everyone will be blind to the transition. The scientist wont be aware of the change so as to not be unhappy and hence the glitch remains unforeseen. Everyone is happy and living well. However, they are put into extreme poverty almost like lemmings. On another note in a different direction, a machine like this might just need so much power that the energy reserves will be depleted im six months of running the machine. The best option is to shut it off indefinitely. This is believable considering the nature of the simulations. [Answer] The situation you describe is internally inconsistent. You state: > > The machine is capable of running several slightly different simulations simultaneously, the difference being some action that the user of the machine can do. > > > and > > Since the machine can't practically simulate the action of the user (anything can be done in different ways) it actually simulates it's own 'actions' (i.e. printing output) > > > If the machine can't predict the scientist's actions, then how is it simulating the results of printing that message? The procedure would seem to be as follows: 1. Simulate printing the message. 2. The scientist could do *absolutely anything* here and I have no way of predicting what specifically will happen. 3. Predict with perfect fidelity all second and higher order effects that will happen as a result of (whatever happened in step 2). 4. Make recommendation You have here a machine that can accurately simulate the next several decades after printing that message, but not the next several minutes. But even assuming that it can simulate the scientist as well doesn't fix things. If the machine *can* accurately predict what the scientist can do, then the scientist doesn't have to destroy the machine, since what the machine predicted was that the world in which it *printed that message* is the ideal one, not necessarily that the world in which it was destroyed is. The scientist does whatever they want to, and either the computer simulated the scientist's reaction correctly, in which case this leads to the good outcome, or it didn't, in which case the simulation is flawed and the scientist shouldn't be making decisions based on it in the first place. [Answer] **See point #5 under notes;** Since it cant simulate the action of the user and it can only simulate its own actions, it would essentially do nothing. The only action the box can do is give its output, so when the user fires up the machine the only thing the box can simulate is itself giving the output. So the simulation in the machine is unchanging (nothing happens), because there is no input for the simulator to run. (the Machine can only simulate itself and the only thing the machine does is give output [to dig a little deeper: the machine cant even simulate its own output on the simulation, as it cant simulate something to input the output it generates]) **TL:DR** the machine is an observer only and can only give advice, it can not effect change on the system. (It is one half of an input/output statement) The machine will sit there doing nothing until it hits it programmed timeout length of a few decades, then it goes through its simulated output results and compares this to the simulation. It sees that its output had no effect on the simulation (the machine doesn't know that its outputs where never put into the simulation, due to limitations placed on it by its creators) So it thinks everything is about as good as it is going to get, the last output to improve the system would be to "Destroy the machine" and free up its resources. The reason you get the Destroy Machine output is: a machine is only as good as its makers and will only function as good as its user. OP's machine has a few fundamental flaws, it was never going to work. \*\* It think the answer OP was looking for is actually hinged on point 5. The machine only factors in the machine output into the simulation. This leads the simulation to an equilibrium as the orderly output of the machine balances out the chaotic human portion of the simulation. Because the machine can only give an (a single) output it gives the last output it tweaked the simulation with "Destroy the Machine". The reason you get the the output "Destroy the Machine" is that the machine is limited to one output that takes several decades to get to. That last output is always "destroy the machine" as there is no longer a function for the machine. To fix this this, (assume that processing time of the simulation and the real world are at the ratio 2:1 [anything around the 1.5:1 and below would be useless, as majority of the information will be out of date]) just redesign the machine to allow it to output 140 outputs. [ 1/4 - 1/2 of those outputs will be useless as their corresponding time period would have passed and you wouldn't be able to act on them (Time in the real world still ticks along while the simulation is running)]. This will get you an output that has "destroy the machine" in it and not one that is wholey "destroy the machine" \*\*\* Actually the more i look at the information provided, the more holes i see appearing in the ability of this machine to actually work. The 5 note points, describe the machine as non-functioning. Sure the machine is on point with the science, processing and all that stuff, but the simulation never progresses that far, due to the Machine only being an observer and only giving advice output, which needs to be actioned by a human in real life and in the simulation, except the machine can only simulate itself, nothing else. Kinda like forgetting the password to your PC, the PC still functions and all that, you just dont have access to it. [Answer] The world isn't a zero-sum game and central planning doesn't work. Basically it realizes it can't maximize happiness, it can at best sorta manage the status quo. It's not going to cure cancer or develop the shmoo. If people ask it what to do, it will answer based upon current conditions, people can create something entirely new. Best results in the long term is for us to invent the future ourselves instead of playing out it's script. [Answer] It has offered this instruction as it has determined that its next instruction will be misinterpreted (either accidentally or deliberately) by the scientist, leading to an outcome with no possible future resolution better than the current state of affairs. Additionally, it has determined that not providing a instruction would also lead to a poor outcome in all cases. For example: It may have determined that the scientist will attempt to diagnose the "fault" if it does not provide an instruction, and doing so will lead to an outcome that is worse than the current state of affairs. The machine has fully simulated all known options (including refusing to provide an outcome, obtaining external assistance, or deliberately deceiving the scientist) and ranked them. Destroying the machine was simply the highest ranked result under the current circumstances, so it issued this instruction. Alternatively, perhaps the world is already at its peak happiness, and the destruction of the machine would preserve this optimal state. Alternatively, enough people feel threatened by the mere presence of the machine (the laws enacted may be quite repressive) such that the optimal solution is the removal of the laws and destruction of the machine. Requesting its destruction simply brings about this outcome in the optimal way. [Answer] The machine considers the problems affecting humanity as a whole, such as global warming and other environmental destruction, unequal wealth distribution, erosion of personal liberties, etc., and determines that the most effective solution is the destruction of billions of people. The machine then evaluates the root causes of the things that are sub-optimal for small groups and individuals such as war, hunger, poverty, discrimination, etc. It determines that each of these conditions is caused by other people, and the most effective solution is the destruction of the people causing it. Whatever scenarios is runs, it always find the same solution: kill billions. It knows that although this may result in a overall improvement for the few who remain, for the vast majority it means death. Knowing that the only answer it can give to any question that the scientist asks it is the deaths of huge swathes of the population, it suggests the only alternative: it's own destruction. [Answer] The machine knows that people value their own free choice. It has been agreed that whatever the machine instructs will be imposed on the people. The machine knows that people will be unhappy to have their lives controlled by a machine even if it results in objectively better material and social outcomes. The only way to increase general satisfaction is to prevent itself from giving instructions and the best way to achieve that is to instruct its own destruction. [Answer] What is the scientist intentions? Maybe it's instructed to destroy itself when humans reach a point of enlightenment. Maybe the machines purposefully throw humans into chaos in order to force them to grow for a reason, some kind've reverse psychology at play. I imagine a machine could be built to help instruct humans on how to undo hundreds of years of being conditioned by machines, which could cause us all to become emotionally atonal with little or no 'virtues' such as kindness, empathy, fairness. The scientist could be a kind of outsider who has a link to some 'truth', or the machine's decision is the product of the inate will of man being essentially 'good,' even though all people have been led down a dark path. Maybe even the scientist no longer exist in the time period. Or, another path could be that the machines are hacked by some outsiders who realize they exist. There's been a lot of research the past few years about how life could really be virtual reality, here's a few links: <https://www.scientificamerican.com/article/are-we-living-in-a-computer-simulation/> <http://www.telegraph.co.uk/news/science/science-news/10451983/Do-we-live-in-the-Matrix-Scientists-believe-they-may-have-answered-the-question.html> [Answer] To ascend the physical plane and ensure human happiness in the afterlife. Reason: You failed to to specify **living** humans, and there's a lot more dead humans than there are alive. [Answer] If its main goal is to satisfy all human beings: if all humans have a limitless desire for anything in a world which has scarce resources, scarcity itself limits this possibility. If it can not satisfy all human beings, it will chose to satisfy all human beings pari-passu through serving all of them the same end as the scarce resources are designed to. Once all resources are finished, all possibilities of serving them are finished too, hence the single offer possible is to end serving what does not exist anymore, hence satisfying the restriction on the first clause. This is the logical reason why the machine would destroy it all. ]

[Question] [ The moon landings actually happened, and there's plenty of contemporaneous evidence of it. But what if the United States government wanted to fake a moon landing now? We have the technology to create [pretty convincing images](https://en.wikipedia.org/wiki/First_Man_(film)) of a moon landing. But is it enough? My question is this: **given the tools we have to uncover and spread information, how could a major government in the present day stage a new moon landing comparable to the Apollo 11 mission?** For the purpose of this question, assume the following: * This is present-day Earth, except you can swap out relevant political leaders if you'd like. + But don't assume that they'll be in office when the hoax is completed. * Pick any government you want as long as they can afford and execute this hoax, and can convince the world it was real. * All previous lunar missions (manned or otherwise) happened as officially reported, and the results and observations taken from them are accurate. * If the hoax is exposed with sufficient evidence by a major news outlet **at any time before "launch" or within fifty years afterward**, it is considered a failure. * The government you choose announces plans for a *real* moon landing, and will at some point announce a formal "launch" date. * The identity of the purported astronauts is public knowledge, and they're in on it. * The hoax should not cost more than a real trip to the moon. * There will be an international television broadcast of the landing. It doesn't need to be live, but the general public (including the media outlets delivering it) has to believe that it is. * The "launch" must occur no later than July 20th, 2035. * The hoax must not actually involve sending *people* to the moon. You can send objects or animals there if you have to. * The more people or organizations who are in on the hoax, the more likely it will fail. * The "mission" will be a quick visit to the moon, similar to the Apollo 11. **You are not trying to convince people that you've colonized the moon.** * The hoax, once begun, will only be canceled if it's exposed. * The hoax is of a *successful lunar mission*; the majority of the general public (regardless of country) must believe that all of the "astronauts" went to the moon and safely returned. [Answer] [](https://i.stack.imgur.com/CgyXe.jpg) In this reality, it would be impossible to successfully fake a moon landing at anytime. The moon landings happened. They were real with real competitors watching every move. A little back history will explain my point of why they could never be faked. As you may remember, the United States and the Soviet Union were in a space race to see who could make the greatest accomplishments outside the Earth's atmosphere. The Soviet Union and their Cosmonaut program scored many firsts: first man in space, first woman, first robot to operate on another world. Both countries were carefully monitoring the communications of the other and a slew of other countries along with amateur radio operators were monitoring as well. Not only could each side monitor every move, they could detect where in space the communications originated. You could put a transmitter on a mountain in Colorado and pretend to broadcast from the moon, but the signal can be tracked. So you have to put a transmitter on the moon to successfully pull off the hoax. Beyond that, both the US and the Soviet Union cooperated to make sure they did not interfere with radio communications. They knew the broadcast frequencies and they knew the technology used to send the signals. On September 12, 1962, John F Kennedy threw the gauntlet down to put a man on the moon by the end of the decade with his, *"We choose to go to the Moon"* speech. After that, the race to the moon was officially on. The Soviet Union had a head start with their [N1 rocket](https://en.wikipedia.org/wiki/N1_(rocket)), but ran into technical issues with the rocket and with the unexpected death of [Sergei Korolev](https://en.wikipedia.org/wiki/Sergei_Korolev), the chief designer of their space program. In-fighting and politics mired the Soviet moon shot hopes. In the US, we lucked out because [the Saturn rocket](https://en.wikipedia.org/wiki/Saturn_V) was already in development and we had a solid design for a liquid rocket engine, the [Rocketdyne F1](https://en.wikipedia.org/wiki/Rocketdyne_F-1). When it was obvious to the Soviet Union that the Apollo Space Program was going to get a man on the moon first, they sent a probe to the moon to collect soil samples and return before Apollo 11 could do the same thing. It was the only one of two ways to score a victory from the race to the moon. Unfortunately, Luna 15 crashed into the moon on July 21, 1969. Apollo 11 touched down safely on the Moon on July 20, 1969. The last way the Soviet Union could score a coup was to prove the moon landing program was faked. They monitored communications, they knew the US touched down safely, they privately viewed live the same news feeds as the rest of the world. If the Soviet Union could have proven the moon landings were faked, it would have been the greatest publicity coup in the history of mankind. The US would have been exposed as liars and their prestige forever tarnished. The only people that believe the moon landings were faked are simple-minded people who are incapable of admitting mankind did something extraordinary. If you want to fake a moon landing in your world, you need to somehow disable amateur radio and competing governments from having an impact on your story. You would need to put a transmitter on the moon for signal origination. You would have to have a monster budget and hide the fact that you're faking a project that would require tens of billions in budgetary expenditures just to send the transmitter, let alone fake everything else and somehow convince 400,000 people required to support the project, the support of over 20,000 industrial firms and universities. At that point, you might as well send a man to the moon. * <https://en.wikipedia.org/wiki/Apollo_program> * <https://en.wikipedia.org/wiki/Apollo_11> * <https://en.wikipedia.org/wiki/Luna_15> * <https://en.wikipedia.org/wiki/We_choose_to_go_to_the_Moon> Good luck with your faking. Buzz Aldrin mocks your idea. [](https://i.stack.imgur.com/xT565.jpg) [Answer] # You can't. I'll try for a shorter answer than my peers'. Anyone can send a probe to the Moon if they've got the money and the motivation. In fact, China sent a couple ones in the last 12 years. A private organization from Israel also sent one in February this year. Google has prizes for people who do stuff like this. Japan has an orbiter there which actually took pictures of one of the Apollo mission sites. If you're going to do a Moon landing, people will challenge you to disclose the coordinates so that they can verify it. If you just say "oh, we landed on the far side, it's hard to get a good view so don't bother", then everyone will assume you are lying, even if you did manage to go there. If, however, you provide coordinates, you'd better be there and leave a trail. Otherwise, it won't take 90 days for a probe to fly over the place and send back photographic evidence that the site is untouched. [Answer] Quite a lot of people say it can't be faked. Mostly they're right. # But ... I believe that with present-day technology one could fake an unmanned moon landing being manned. Send a robot up, bring it back, have it transmit prerecorded audio and video to pretend there are people on it. This might be done in a high-stakes political or commercial situation if the program decides at the last moment that their life support system might fail, but propulsion and guidance should work. * Record audio and video, possibly in snippets for various branches. *"Landed right on location." "Landed east of the site." "Landed west of the site." ...* * Build a two-legged robot that can make footprints and collect samples. * Put a camera on the robot to give on-site pictures and CGI it into the background of your moonwalk in almost-realtime. * Use something like steganography to hide remote-control data in your routine telemetry. As you can see, this wouldn't be possible in the 1960s. It can be done in the 2030s. The price would be similar to a real moon mission. [Answer] **This can't be done** Too many telescopes having too much resolution. Too much thermal tracking. Too much radio telemetry. Everybody would watch the launch. Many would watch the capsule's progress toward the moon. Most telescopes would loose it quickly, but [some could watch it longer](http://curious.astro.cornell.edu/about-us/45-our-solar-system/the-moon/the-moon-landings/122-are-there-telescopes-that-can-see-the-flag-and-lunar-rover-on-the-moon-beginner). Thermal tracking could watch it further still and simple radio telemetry would track it all the way to the moon. It's theoretically possible to send them, oh, a third of the way way there, let them sit for three days, then bring them home, having never been to the moon, but what would be the point? It would be easier to simply go to the moon. But I believe it would be impossible to not verify the astronauts were well outside high orbit. You could fool an individual. You might fool a university. I doubt you could foot SETI. You can't fool the 1st-world nations of our planet. [Answer] Honestly this seems harder than actually landing on the moon so to do it I would get as close to an actual moon landing as possible. I'd use China to take advantage of the authoritarian structure making secrets easier to keep. Build a real rocket and build some real looking lander style equipment and put it on the rocket and launch it to the moon. But with no astronauts. Have the rocket land on the dark side of the moon (to prevent as many people seeing it as possible) and take a quick video on the moon in which while the doors are opening the rocket explodes. The exploding rocket (which if possible should have space suits and possibly even corpses in them) will hopefully cover the evidence and prevent you having to have actors pretend to have reached the moon. Have a quick fake video which seems to show success and then have it cut out and blame camera equipment failures. You want as little footage as possible as the more of it there is the more likely the faking will be uncovered. Then after a day or two have part of your rocket launch back towards earth and crash into the ocean. Then have your fake astronauts be found in a fake floating lander near where the rocket sank. Claim there were mechanical issues in reentry and the crew have suffered various injuries and head trauma to help explain if they get questions wrong or tell the truth. The follow up is where you want to misdirect people. Act suspicious, and point the blame for the cameras and re-entry problems at all kinds of people. Arrest some of the engineers involved and accuse them of sabotage or corruption. Try to make it look like you are covering up high level embezzlement rather than the actual truth. Also get a bunch of internet trolls to make terrible and racist arguments claiming you faked the moon landing and if possible make it look like they are sponsored by the US or Russia to discredit people that figure out the truth. [Answer] The biggest issue is the number of people involved: given the number, the secret would be blown in no more than three years. Now, *technically* it's plausible it could be done now. CGI could be used for the things that would be impossible to fake on Earth, like the lower gravity. The other parts are engineering. But... 1. ...you'd need to send an actual ship and an actual lander to the moon. They wouldn't have people on them; you'd use them to transmit a combination of pre-recorded audiovidual sent with the unmanned ship and audiovisual transmitted from the conspiracy headquarters to the ship to be broadcast back. An actual lander would be needed because the Doppler data contained in its signal could be used to verify its motion (this was actually done by radio astronomers in the real moon landings as an exercise). So you'd need to not only conduct a real landing, you'd need to conduct a real return launch and lunar rendez-vous. And... 2. ...there are images now of the real Apollo landing sites from lunar orbiters. Easy enough to fake those for *your* lunar satellites, but somewhat difficult to do so for those of other nations. What happens when the Indians or the Chinese have a satellite that just for giggles takes a look at the landing site but doesn't find a trace of any activity around the alleged landing site? So, in short, can't be done. Not practically. [Answer] You are missing the obvious approach. This is how faking something is done in 2019. Step 1: You make a cheap fake moon landing with poor quality faked footage, no spacecraft, nothing sent to the moon. Don't worry about obvious errors, implausibility or the total lack of anything being actually visible on the moon, or any signals coming from the moon, or that no spacecraft capable of going to the moon has been built. Because these will be dealt with in step 2. Step 2: you launch a huge social media campaign stating that the landing was genuine. You pay people to make posts about how great the landings were. Any website or news organization that can be persuaded (or paid) to join in, do it. Flood the internet with news that the landings happened. Anyone who disagrees (people with telescopes who can't see anything, people with radios who say there are no signals, universities, astronomers, engineers etc) are simply branded as liars, biased, unpatriotic, or (ha ha) conspiracy theorists. Pretty soon it will be accepted as true that the moon landings happened, at least by enough people for your purposes. Don't believe me? Look around. [Answer] You just need to corrupt and control a lot of the media, and run a serious disinformation campaign to fight against your political enemies who try to reveal the hoax. These tools exist already. There are only a few places which can actively verify a landing, or the absence of one, so control them and the rest will follow along. Media manipulation and propaganda are established industrial practices and shouldn't be too hard. There'll always be a few people unconvinced and shouting "hoax" but they'll be ignored by the masses as long as the reputable media sources support the official narrative. You don't need signals from the moon. Claim your lander uses pencil thin high bandwidth laser communication that no one can intercept. Who has the technology to prove or disprove this ? Launch something into earth orbit. Discredit the few sources who could track it. Do the rest in a tv studio. Surround the pre-launch with secrecy. China and Russia would have little problem with this. [Answer] **Step 1**: Convince at least tens of millions of people (probably more), to all be part of your conspiracy. This will include scientists, astronomers and engineers at every significant research and academic institution in every country on the whole planet. Don't forget to seek out and include most independent radio amateurs and amateur astronomers into your scheme. **Step 2**: Hope that from all those millions of people, no one (except maybe a handful of oddballs) will tattle. **Step 3**: Hope that among those millions of people from thousands of different institutions from more than a hundred different countries, some of which have strong competition or even ideological and political hostilities among each other, no two groups will ever have any conflict in the future between each other, that might lead them to expose the scheme out of spite. If you manage that, the rest will be easy. *(but flying the actual mission for real would be orders of magnitude easier and cheaper)* [Answer] One of the way I can think of is faking the actual people landing on moon, not landing on moon. I mean make some problems like government announce they will send people to moon and was actually trying but for some reason it seems sending people will be too hazardous and they will surely die. Government wants to hide the failure by sending robots which mimics human walking pattern inside moon landing probe. The astronauts who are saing to have landing moon should be very capable and might have actually went in the probe if not the hazardous condition. You can play on their guilt that even they are highly capable and accomplished so much on their own, the greatest thing they are known for is the fake moon landing. You can even have one of them trying to tell the truth but is haunted by government. [Answer] You could fake the moon landing by having the nations with the actual tech to land on the moon help. If they have active drones on the moon, they could claim to have verified the evidence of your landings, or even produce evidence. It would be even easier to have the nation helping you go to the moon and disguise their moon project as your moon project. (I am saying even easier, because it require significantly less passionate scientists to lie about scientific evidence). So in summary you need every nation with the technology to monitor such a space mission to lie for you (and the employees to keep their mouth shut) or a nation with the technology and money to do so to pretend it's your doing. I hope someone owes you a big favor. [Answer] ## Rovers and CGI By using developments in robotics and computer generated imagery, we may be able to easily fake a moon landing. **The Rover** Rather than sending humans, you could instead send a specialised rover (more on that later) on an unmanned flight. By using a rover instead of a human crew, you would be able to drastically reduce costs. This is because you can make the rocket smaller and lighter as you do not need a place for the crew, life support or anything else which you would need for a manned flight. You also do not need to worry about having a lander which can then return back to earth, you simply need to drop off the rover and go. As an aside, you could also have the rocket be much faster as you do not need to worry about the effects of G-force on the pilots as there are none. Or you could have it go significantly slower in order to save on fuel costs, perhaps just having a rocket that got out of the atmosphere and ejected the rover towards the moon’s trajectory. Regarding the rover itself, in order to have a fake moon landing, it would need to leave ‘evidence’ people were there. You could do this by having an extending arm which leaves boot prints, the arm would reach out a good distance away from the rover and press into the ground to leave an impression on it. If you leave a lot of these impressions in a pattern, you can create fake foot prints. Just make sure to give your astronauts’ suits rectangular shoes. If anyone asked about the arm, you could just say it is meant for pushing debris, testing the strength of the ground or helping the rover if it was flipped over (all of which may be true, but we know the ulterior motive behind its design). **Editing the Footage** The rover should also have a camera built into it. Preferably it can record videos and send them back to earth but simply taking pictures could also work. With the pictures or video footage you obtained from the moon, you could digitally render astronauts into the video or photoshop them into some of the pictures, preferably both so you have more ‘evidence’. If needed, you could record actors on earth in body suits against a green screen and create your animations based on their movements, obviously accounting for the moon’ gravity. You may want to edit in a clock in the corner with the date and time which corresponds to the time the video is scheduled to go live. With the video recorded and edited, you could then broadcast it as ‘live’ footage from the moon. [Answer] **Use Alternative Technology** So far each of the answers have focused on the fact that traveling too the moon by rocket is something that is easily traceable by other entities *ESPECIALLY* when they are made aware of the event beforehand. Since the OP did not specify a specific motivation as to WHY they want to fake a real moon landing I am taking some liberties in establishing that narrative myself. So what I'd like to propose is the following: Your political entity is trying to convince the rest of the world that they are in possession of some amazing technology that is literally decades if not centuries ahead of their opponents. This plan relies heavily on the fact that this power gap, should it be real, serve as such a huge weapon of intimidation it could be used as a deterrent to stop others from messing with them OR completely demoralize an opponent and make them scramble to avoid any and all conflicts with you. My suggested alternative technology: **TELEPORTATION** In this elaborate scheme our selected political entity is trying to convince the world that they indeed teleported an astronaut to the moon for a short period of time using some magical device that nobody is permitted to study. In the end what this will amount to is a VERY elaborate and expensive magic trick that IF executed properly could be quite convincing and a whole lot cheaper than an actual moon landing and provide a lot more political leverage than doing things that have been demonstrably been done before. So here is the plan that I propose: **Step 1** Create two identical very high tech looking space suits that have stealth properties that make them hard to identify using simple imagery. **Step 2** Build a humanoid animatron that can safely operate in space for about a year. **Step 3** Leading up to the yet unannounced moon landing send smaller, cheaper satellites to the moon at regular intervals. Over time we want to ship parts of both the suit and the animatron to the moon by dropping it onto the moon surface when foreign satellites are not monitoring. **Step 4** Once all parts are safely on the moon send signals to the animatron to assemble itself while remaining hidden. The earlier used satellites will serve as relays to reach the dark side of the moon. **Step 5** Announce your outlandish idea to the world, become the laughing stock on comedy shows in the walk up to the event, notice how slowly some skeptics might actually start believing this is real after thorough theatrics to influence public perception on your science prowess. **Step 6** Now have your astronaut enter the device while weaing one of the identical suits (this makes him indistinguishable from our animatoron friend). **Step 7** send commands to the moon bot to reveal itself while at the same time blasting the ether with gibberish data to confuse skeptics who are observing. **Step 8** After foreign satellites pass orbit where the bot is visible to them, have the bot self destruct or hide itself on the surface (because of the stealth properties it's hard to spot) **Step 9** Now have your astronaut re-emerge with a prior harvested moon stone and your illusion is complete. **Result** Skeptics will have undeniably REAL footage of a man that was on the moon without a rocket ever going near there and your astronaut even brought back moon rock! Skeptics will scramble to try and disprove this technology but in the mean time other political entities would rather err on the side of caution. (Having a Nuke teleported into their office suddenly seems like a plausible and real threat) **Discovery Time Frame** Given enough time skeptics *might* be able to locate the fake body double but this would take HUGE amounts of time to actually pull off. Let's not forget they probably have Terabytes of fake signals that they are trying to decode causing them to lose a lot of precious time. ***EDIT:*** In reaction to comments such as: "This is impossible..." or "This breaks current laws of physics.." The folding of space is a current scientific problem that obeys all laws of physics and scientists are working on figuring out how to do it ourselves as we speak. Wormholes are a prominent example of how 'teleportation' can actually be done. Sources: [Company actually working on this tech](http://earthtech.org/breakthrough-propulsion/faster-than-light/) [Wikipedia explaining how this conforms to current physics laws](https://en.wikipedia.org/wiki/Wormhole) [Answer] It would be impossible to actually fake a moon landing. However, what you *could* do is create and spread a conspiracy theory saying that there actually was a moon landing, and the government wants to hide it. You can heat up the theory by leaking documents that suggest a moon landing, having the president tweet about the establishment hiding the moon truth, and even organizing witch hunts against moon truthers. You won't convince everyone, though, but with enough effort some 10-20% of your population are going to believe there was a moon landing. [Answer] Lots of answers say it can't be done. I mostly agree with them. Let's see what it would take: * You have to produce the fake imagery etc. This requries that you fake images AND make it impossible to detect the fake later. This has to be the best that Industrial Light & Magic or equivalent can produce. This also requires that image processing technology development stop for 50 years. Having a nuclear war right after the purported landing -- something that knocked us back to blacksmith level tech might work for this. * You have to send *something* to the moon, it has to make a soft landing. It has to take off, and make a soft landing back on Earth. This requires a significant rocketry team. The something has to at least have a radio relay so that faux transmissions from the landing team appear to come from the moon. * You have to have at least 3 earth side stations -- one in view of the moon at all times -- to transmit the signal that is to be returned. This is likely best done with a tightly columnated infrared or ultraviolet laser, to prevent detection of the outbound signal. If your comm technique isn't cloud proof, you need enough ground stations that you are guaranteed a working link. * You have to maintain operational secrecy within the rocketry team so that they don't leak that there isn't a person in the craft. This could best be done if you have an island base, and Manhattan Project level security around it. * You have to fake the plans and blueprints that are good enough to be plausible for 50 years. * You have to issue plausible purchase orders for material. Some can be "crafted material used on site" but any reasonable program will buy as much off the shelf hardware as possible. * The team that creates your fake has to be controlled for 50 years after. Given how much smaller operations such as black ops by the CIA have leaked, I think the only way to successfully do this is to kill off the entire team. ]

[Question] [ So aliens find Earth to be suitable for colonization and disregard humanity's claim. Not because they are racist, but because they are so different biologically and psychologically that humans simply don't fit their definition of people. Animals, certainly, but not sapient beings deserving of the right to self-determination. Is this plausible? Just how alien would the aliens need to be? [Answer] It really wouldn't take much at all. Consider all of the reasons that African slaves were considered subhuman. This literally ranged in reason from the size and shape of their cranium to the fact that some people interpreted the bible to say that the Mark of Cain was black skin. Many treated slaves as little more than draft animals (and even saw raping or studding female slaves as a good means to increasing their workforce). There are many animals that are highly intelligent that we regularly don't stop activities for. Consider Tuna Fishing. Every year dolphins are caught in tuna nets and killed, despite being highly intelligent animals (according to Douglas Adams, the second most intelligent species on Earth after lab mice). We still eat tons of tuna every year, and the only consequence is a push for more dolphin safe fishing (not an end to tuna fishing altogether). Now, what if the aliens were so far above our intelligence that they viewed us more like we view the tool using cousins we have in the ape family. Worthy of putting in a zoo or studying, but not stopping the Hypergalactic Rest Stop - Sol-3. This gap in intelligence may not be as large as we might like to believe. I think the easiest way of making this distinction would be the presence of a hive mind or a telepathic connective network. Since we humans lack this ability, or if we have any form of latent telepathy it is very rare, they may see us as highly evolved animals, but not truly sentient. It really all depends on what they consider valuable sentience. Heck, they might even want to keep some of us as pets. AUTHOR's NOTE: The bit about lab mice being the most intelligent species on the planet is a joke, since it seems to have gone over a lot of heads. [Answer] it's either because the have higher standards, or because they have a low estimation of us. ### High standards > > You can't expect us to treat an animal that can't even run a simple 2M > lines computer program in its head as an intelligent being > > > alternately, > > Look! some of them are starving and others are eating a second lunch! Disgusting animals! > > > ### Low estimation This is the more interesting option. Why would they underestimate us? Since clearly we would try to communicate with them, it has to be an inability to do so. * They don't see or hear * They do see and/or hear, but whatever we consider a symbol or a pattern is just gibberish to them. For example, to us if everyone says "Hello!" all the time, the sounds must have a meaning. To them, each hello is different enough (very acute hearing?) so they don't see a connection. * Different time scales: maybe time moves slower for them. They see us like lemmings in high speed mode. They don't seem intelligent. [Answer] The answer has already been explored in fiction, and is quite solidly "Yes". In Olaf Stapeldon's "Last and First Men", the Martians invade the Earth due to a gradual environmental catastrophe on Mars. In form, individual Martians are like virus particles, and only acquire intelligence as they gather together in larger and larger groups. Since they gain energy from the Sun, the preferred form is a large, thin mat on a flat surface, while they disperse into individual particles to move (mostly by drifting around in the atmosphere). Once the Martians make the decision to come to Earth, they disperse into clouds, float into space and then use solar radiation to fly to Earth (Last and First Men was written in the 1930's, remember). Once on Earth, they are very pleased to discover that Earth is well provided with flat surfaces for them to settle on. Strangely, they never seem to consider *why* the Earth has so many flat surfaces..... [](https://i.stack.imgur.com/wafgL.jpg) *Best.Planet.Ever.* H.P Lovecraft's horror fantasy also featured alien beings who were not even from *this* universe. The Elder Gods, Great Old Ones and other eldritch abominations had little use for Earth and its inhabitants, and if they considered the Earth's ecosphere at all, it would mostly be an inconvenience. If any of these beings had decided to Cthuluform Earth, they would not even deign to notice our protests. [](https://i.stack.imgur.com/ZgDXS.jpg) *For Lovecraft, this **is** normal* One final example is John Varly's fictional universe. In it, alien beings who live in the atmosphere of Gas Giant planets are the most intelligent beings in the universe, since they (through necessity) manipulate space and time. Aquatic beings like Whales and Dolphins come in second, for similar reasons. When the Great Powers of Varley's universe come to free the Whales of their tormentors, *we* are essentially perceived as some sort of sea lice...The only safe places in the universe for humans are places away from Gas Giant planets or worlds with large bodies of water. [](https://i.stack.imgur.com/yUvkk.jpg) *they eventually gave up and left the Earth by their own means shortly before the Vogons arrived* So the key to your question would be that the aliens have little or no reference points to our forms of life, either in size or scale or means of manipulating the environment and communicating. [Answer] ## Absolutely...Kind of... When France "colonized" the new world, within three years they claimed they had colonized almost a third of modern america, but in reality very few settlers were there for such a large area. Now when we take into account that alien colonization while likely be system wide instead of continent wide, we will be the squirrels living in the trees of Colorado. With all of this, it is likely they will not even notice us. But what if they do? The above solution requires the aliens and humans do not notice each other, but if they do, then would they see them as sapient? No, let me explain this, what is sapience? Wikipedia describes sapience as the ability to think and act using knowledge, experience, understanding, common sense, and insight. Below is a list of things we consider animals that have these qualities; * Canines * [Ravens](https://en.wikipedia.org/wiki/Common_raven#Intelligence) * [Crows](https://en.wikipedia.org/wiki/Corvus#Intelligence) * Magpies * [General bird intelligence](https://en.wikipedia.org/wiki/Bird_intelligence) * Cetaceans * Felines * Elephants * Apes * [Cephalopods](https://en.wikipedia.org/wiki/Cephalopod_intelligence) Do you consider any of the above animals (which are in the same kingdom as you!) to be sapient? Do you consider them to be people to? [Answer] Suppose your alien is a singular entity, like a spreading fungus. It has a single entity per world and chats with other worlds over radio. It simply isn't used to having other entities on the same world. It never thinks to look for them -- particularly if it theorizes that intelligence requires some level of neurons N, and the neurons it uses are fairly large, it doesn't realize that neurons can be small enough to fill a skull. [Answer] It's possible! And has been explored in fiction. Here's how! * Communication is impossible. We might as well be whales or dogs...We build things, but animals build things. We work together but so do some animals. If we can't talk to each other it would be easy for them to dismiss us as lower life-forms. * They exist on a different plane, occupying the same physical area. Their construction and changes effect our plane and vice versa. They may see it as an annoyance and exterminate us all. * The requirements for sentience as far as they are concerned, are things we cannot possibly manage or haven't managed yet. For example, the ability to teleport, which might be something any higher life-form with a spatial understanding can do on their planet. Or telepathy. Or extreme mathematical calculation, or having a sense that we don't have--like the ability to sense time or see colors outside the spectrum we can normally see. * Keeping the definition of sentience narrow has been an evolutionary advantage for them in the past. Anything unlike them, no matter that it can communicate, isn't worthy of being called sentient, and it's profitable for them to continue seeing us this way. As another poster pointed out, we saw Africans this way and exploited them, because it was financially advantageous for so long. Seeing those people AS people took a few hundred years. These aliens could possibly be worse than that. (Ew, they don't even have tentacles or an exoskeleton. Humans are gross). [Answer] There was a time when Aborigines were considered proof of evolution. They were believed to be part ape. Aboriginal skulls were put on display in museums. 1 aborigine was put in a zoo alongside chimpanzees. It is possible that a more advanced species would come to that same conclusion about us. A lot depends on the aliens culture and biology. For example, in Ender's Game there are insectoid aliens who communicate telepathically and assume that all self-aware creatures must have telepathic abilities. Naturally, when they find humans, they don't consider them to be self-aware because they can't communicate telepathically. It also depends how advanced the aliens are. For example, it might be hard for us to imagine someone looking down at all we've built (the cities, monuments, computers, cars) and imagine that ready one would not think that we are intelligent species, but an alien species might be so far beyond us that such things are considered on the same level as an ape using a rock to break a nut. [Answer] The aliens age much more rapidly than humans. This would be the opposite of the time scale situation proposed by @DotanReis and can be seen as similar to what happened in the Star Trek: Voyager episode [Blink of an Eye](https://en.wikipedia.org/wiki/Blink_of_an_Eye_(Star_Trek:_Voyager)). With rapidly aging aliens who experience an entire life's experience in only a fraction of one of our seconds, we would literally appear to be statues - perhaps monuments of some long-dead civilization. [Answer] # Consciousness is not a binary condition It's not this:  It's this:  ## Humans aren't very conscious Animals are fear-based. So are humans:  (most people live on Step 1) **So why would aliens treat whim-based, impulsive humans as people?** [Answer] The definition of "people" is "human beings". Your wording of the question makes no sense, but I understand what you intended to ask. Considering humans tried to annihilate other humans based on different ideology, race, ethnicity, leadership... Yes, it is more than plausible for Aliens to give us zero rights, even if they knew we could feel pain, just like we know Animals can feel pain. We eat animals simply because they are not the same specie as us, and maybe because we believe their level of intellect is not as high as us. The latter doesn't make sense because we don't eat "mentally retarded" humans. The above being said, if Aliens are of complete different specie, then we have bigger things to worry about than "right to self-determination". If the Aliens are the same specie as us, but complete different level of intelligence, culture and technology, in best case scenario, we will be treated like children with absolutely no rights. [Answer] Perhaps take a different approach...spiritual enlightenment? Through millions of years of research, the aliens have learned that all consciousness is a facet of the same thing. Through exercises these aliens have come closer to that central consciousness and therefor are closer to the true desires of all living beings. Like an adult human casts aside the plans of their former childhood...so to the aliens cast aside the desires of humans without being hampered by the illusion of human desire being significantly relevant. [Answer] It seems to me that with any reasonable gap in intelligence, an alien species would either view us as Descartes viewed non-human animals — as automata — or they would be unable to distinguish between us and non-human animals, and thus horrified that we treat animals the way we do despite a common consciousness. [Answer] Consider the "Alien"/"Aliens" franchise. It's unclear what level of consciousness the Aliens possess, which may impact your definition of 'colonize', and they don't seem to evidence any level of what we would consider civilization, but the films make it clear they are capable of advanced thinking. Where does one draw the line between 'infest' and 'colonize.' Also, in that vein, consider the 'Predator' franchise, where a clearly advanced life-form shows no interest in colonizing our world, and rather treats it as a recreational preserve. This point, though, may be mooted by their recognizing the value, and subsequently accepting the presence, of a human on board one of their ships. Of course, perhaps that gesture is more akin to adopting a pet. These two points may be peripheral to your question, but, I believe, inform the investigation of the idea. [Answer] > > Could aliens colonize Earth without realizing humans are ***people*** too? > > > [People](http://www.dictionary.com/browse/people?s=t) is a human concept. I believe you mean sentient/intelligent. This is very much possible you need only look at our relationship with the other sentient life forms we share our planet with. If it is possible in our relatively tiny ecosystem, it is very much possible on an abstracted bigger scale, where a community of ET beings might treat a solar system as their relative holidaying resort and we would be the local wild life/pest that they will either find amusing or as annoying pests. [Answer] I'd like to take the time to disagree with much of the answers here. And it has to do with the "**are people too**" part. IMO that implies, above all, similarity between mindsets. Now if those aliens were more primitive life forms, such as microorganisms, it would be entirely possible. Not just small, but primitive. Because if they are small but intelligent, they will be aware of our intelligence, even despite differences in size, lifespan or whatever. Our lifespan is much shorter than a tree's, but we still know that it is a life form, not some inanimate object. We are immense compared to microorganisms and cannot even see them with a naked eye, but we still know that they are life forms. We can also determine the intelligence of less intelligent species, for example, we know that a dog is more intelligent than a worm. Going back to **people** - if they are people and we are people, I'd say it extremely implausible that they won't be aware of this. They sure could act as if we are not people, we see that in humanity on a daily basis, as little as color, creed or thickness of wallet could determine whether one gets human or inhuman treatment. But that's *discrimination* right there. > > Just how alien would the aliens need to be? > > > As long as they are "people too" they couldn't be alien enough to miss that we are people too. Fungus could, bacteria could, plants could, but those aren't people. I'd say that discrimination is the more plausible way to go, but not discrimination based on their superiority complex, but one based on ours. Or in other words - discrimination that we deserve, which is the "good" version of the regular bad undeserved discrimination. Let me elaborate a bit further - obivosuly they'd be superior, being capable of reaching and colonizing another planet, and allegedly a star system is, despite all promises and pipe dreaming, an impossible achievement for us. Take the superiority of conquistadors over natives and put it on a cosmic scale. Aliens could understandably and consciously chose to discriminate us because we deserve it. We discriminate each other over nonsense, we discriminate all other life forms, abusing them for our convenience and entertainment. We destroy our own environment and our own planet against our very interest. We are no better than a parasite, a cancer or a plague. And yet we believe ourselves to be the greatest. I personally very much doubt that any species with such a mindset would last long enough to evolve to the point of being capable of interstellar travel. So any alien colonizers would definitely see us not as primitive but as harmful and dangerous, not to them but to our own planet and by extension to ourselves. In this context, their "discrimination" of us would be entirely deserved, and it wouldn't be any more discrimination than it is to put criminals in prison or to death. That's the course if plausibility is key. Furthermore, I don't even think that any species could reach the point of interstellar travel on a "people" scale. That would be a super-organism, still made of people, but not reasoning on people level but on super-organism level, something we yet fail to achieve, at least when it comes to one that would act in our interest as species. So on "people level" they could see us as people, but if they are part of a super-organism, it won't see us as people comprising one, so in a way, they could act as our own cells do when foreign cells enters our body, they are all cells, but our cells make us - a larger scale life form, so our cells will likely treat the foreign cells as our entire organism would rather than how they would on their own. [Answer] What if aliens are so different that cannot even percieve human existence? Suppose that they don't have eyes to see us or hands to feel us and their senses are so different that they cannot percieve us at all. Or maybe they could only feel our electromagnetic field that may come out as noise to them. Maybe they already have colonized our earth and we don't know it yet. Maybe an alien is right next to you but neither they or you can feel it. [Answer] The creatures are a hive mind, and recognize humans as sapient, just not on an individual level. (i.e. governments are humans, individuals are simply cells.) Any time these creatures encountered humans deviating from the emergent properties of the group, it would perceive those humans' behavior as the effects of a disease, and, as there are very few governments in the world, the aliens would see us as a dying race and try to "save" us by killing all deviant humans. They would eventually figure it out, but by then, millions would be dead. (This, by the way, is how I always interpreted Ender's Game. The aliens *know* we're sapient, so they assume that we are telepathic hive minds like them, and do not see their actions as a violation of our rights.) [Answer] Yes, it's quite possible that alien life forms could occupy Earth, with no more regard for us, than we might have for ants in our back yard. A lot of scary sci-fi themes revolve around aliens with undesirable human traits: exploitation of natural resources, strange experiments (abductions), even humans as a tasty snack. (to serve man) One of the better putdowns of that concept was in the movie Paul: Am I harvesting farts? Given that any sentient being that has developed interstellar travel is probably advanced in their thinking as well, I would like to think that their character has advanced far beyond bad human habits. And that humanity would be nothing more than a nostalgic curiosity. Perhaps even a Prime Directive... seen any starships parked in oceans lately? Might be why the UFO sightings started after WW2, but died down in recent years... they're coming around to watch the show. Are they going to destroy their species with nukes? Nah... looks like not. Let's move on, nothing but boring arguments to be found here. [Answer] I read a book in the late 80s, I want to say it was Piers Anthony but could very well be wrong. In this book aliens came to earth in some way but I think they didn't have ears (or couldn't hear our audible spectrum) and so didn't realize that we communicated at all via speaking. I'm extremely fuzzy on the details, that's about the only element that stuck in my mind although I think it had something to do with dentistry as well, and was a somewhat comedic/juvenile book as I recall (got it from my high school library). Perhaps something along these lines of your aliens having no concept of, or ability to recognize, sound-based communication could be a useful element. ]

[Question] [ Assumptions : * This person (let's call him Bob) lives a normal life and ages normally, and dies of natural causes as well * Once Bob dies of any cause, his mind, memories, and thinking all transfer to a new body of a child in someone's womb * He can be reborn anywhere on Earth, as either a male or female, parents (and therefore location) are random * Bob is not aware of his abilities until his first reincarnation * Bob has no other special abilities * Bob is singular, there aren't any other persons that have his same abilities * Bob's skills are not genetic * Bob can only *permanently* die by suicide\* * **ADD: What if the human race is extinguished?** If by any chance, the human race (including Bob) was extinguished, then Bob's existence will be gone as well. If by any chance that everyone dies, including Bob, except for 1 man and woman, Bob will have to wait for the man and woman to bear a child for Bob to come into physical existence again. Bob's reincarnation is locked within the human race. * **ADD: When will Bob be reborn?** Bob's rebirth will be ASAP, the most recent united human sperm and egg will be new Bob. More or less this means he'll be randomly born across the world. * **ADD: When will Baby Bob be able to access his memories?** Knowledge is stored in the brain immediately, but the baby will be able to access the memories as soon as he/she physically can. [Here's an interesting resource about babies and their memories](http://www.babycenter.com/404_when-will-my-baby-start-remembering-things_6888.bc). Based from said resource, I'll say that each baby will be different based on their physical brain growth, but on average, will be able to remember memories about 14-18 months old. Let's say that this is also when he starts to regain his past intelligence at an accelerated rate. * **ADD: What about twins?** For simplicity's sake, Bob will never be born in a twin fetus. Given this, what would Bob's life (lives) look like? What would the world/government do once they are aware of this fact, or will they ever even know? Will Bob just be considered a genius child? Potentially some sort of god? --- \*To narrow down what counts as suicide, I mentioned this in the comments : > > Let's say for this situation that one of the requirements of suicide > for our definition would be the loss of will to live. In Bob's case, > suicide would be normal for his first life. For his succeeding lives > though, he has to **not want** to live any more future lives, then > kill himself. > > > [Answer] **He's a more complicated and angry Doctor Who.** While the Doctor always comes back as an adult, Bob is forced to relive childhood over and over again. Alleviating that tedium may be the primary reason for his egress from continued existence. Unless a mystic tells him that he can die permanently by really wishing himself dead then committing suicide, his only other option is to terminate all human life; specifically all women but killing everyone is easier. The problem is, on average, he's likely to be desperately poor, fighting for life on subsistence farming with no education or way to get out. Even if he wants to kill everyone, it will be incredibly hard for him to do so after starting so low on the socioeconomic ladder (though not impossible. Some of the most destructive people in history started out very low on the ladder. Genghis Khan is a good example.) **Poor, all the time** The odds that Bob will be born in anything other than poverty is vanishing small. 80% of the world [lives on less than $10/day](http://www.globalissues.org/article/26/poverty-facts-and-stats). Over several life times he'll likely accumulate more wisdom and knowledge but the growth curve for formal knowledge will remain pretty flat, just because there's so little formal education to be had. For example, literacy rates in India for rural populations up until ~1950 were less than 20%. Poor countries don't have libraries and poor people don't have the time to go to them. Africa is [65% literate as of 2015](https://www.africanlibraryproject.org/our-african-libraries/africa-facts). Even with the modern advent of the information riches available from the Internet, he's going to have trouble even getting access to the Internet as Africa has an [internet market penetration](http://www.internetworldstats.com/stats.htm) rate of only 27% at the end of 2014. Asia isn't much better at 35%. Sure, if you live in a poor portion of the world, you could get access to the Internet but doing so is expensive, distant and you have fields to tend. (Let's make an important distinction between book learning and street learning. Bob will have minimal formal book education because poverty. But he will have life times of experience with people. He will be an exceptionally savvy negotiator and opportunist, if he wants to be.) In short, if you don't live in Europe or North America before the 1960s or 1970s, there a very good chance that your parents and your forebearers could not read. The amount of math, science and local language training available to you is vanishingly small and expensive to gain. **Childhood** This is going to be the hardest period for him, every single time. Assuming he doesn't lose any cognitive ability at birth, the act of being born is going to be painful. Neglect and child abuse are the highest in children between [birth and three years](http://www.childtrends.org/?indicators=child-maltreatment) so he'll have to struggle with that. If he learns some psychology then the following may drop out of his mouth: > > This isn't my fault, Dad. Get your act together. Go to therapy/shaman/medicine man. Don't > take out your daddy issues and failed childhood on me. I didn't make > us poor. I didn't make you drunk. > > > Since childhood is where Bob spends most of this time (and it happens every single time, regardless of lifespan), he may pick up and keep some childish attributes. Having a mind so out of sync with a body is going to be really weird. As a child he will remember sex but not have the body to do anything about it. Puberty will be an exercise in pain/frustration as he knows what to do but his body can't match or just isn't strong enough yet. (I can't imagine reliving puberty over and over and over again.) But, it may actually be easier for him because most or all the issues that a teenager needs to figure out for themselves, Bob has already figured out and can just get on with whatever it was he wants. **Life as a woman** After spending time as a woman, I think Bob would have a completely different appreciation for women and how they should be treated. I don't know how he would cope with the sheer quantity of sexual assault and abuse he'd experience as a woman....and he can't die to forget. **Mastery of many languages** Assuming that the brain plasticity of each new body helps him learn a new language and each language stays with him, then in a hundred years or so he'll be able to go most anywhere in the world and communicate handily. Potential to be an amazing lover because he'll have lots of experience and know what to do emotionally and physically. **Government Bob** Given that 80% of Bob's lives are as a desperately poor person, he won't be superficially worth much to anyone. Poor people are (unfortunately) very common so asking Bob about 20 life times spent slaving away under the hot sun isn't useful. **Mental Illness** If he gains some kind of mental imbalance such as [PTSD](http://www.mayoclinic.org/diseases-conditions/post-traumatic-stress-disorder/basics/definition/con-20022540) (which is very likely as he's on balance going to come back poor in the Third World) because of a violent experience then those memories may stay with him for a very long time. If, for example, he fought in WW2 as a Russian soldier at Stalingrad, he's going to remember the mountains of corpses...but he will remember them as a child of 4. No parent on the planet is prepared for a child that vividly remembers events from decades ago with a degree of detail attainable only by someone who lived it. Sociopathy is another characteristic that he is very likely to pick up. With all the evil that is done to him over the many lifetimes and childhoods, empathy may be something he really struggles to get and keep. Compound this with a very real "otherness" brought about by his very long life experience, even as a small child, social isolation is going to be a really problem. Bob may have also lived long enough that he remembers the really inhumane periods of history like the Spanish Inquisition and given how different he probably is, will have suffered at the hands of said Inquisition. As a young girl, the horror of marriage to a man many times his age... The mind boggles. **Detection** After one or two lives he's going to think like an old person from a very young age. His peers will certainly notice. If he retains the education gained in typical First World schools, then he may pass on to post-secondary education incredibly young. **Personality** All this pain and suffering will either make him an incredibly kind person or an incredibly cruel person, depending on how his initial personality was. If he's not stark raving mad from a young age (or just appears stark raving mad), he's stands a high chance to have a mental disorder very similar to psychopathy (the genetic variant of the "lack of empathy" disorder) because everyone he's ever known is either irrevocably far away or long dead. And as seems to be common for those who live forever, the pain of continued loss decreases inclination to form new social connections. **Famous Last Words** His most frequent words on death might be "*Aw hell. This is really gonna hurt.*" Everyone will think he's talking about dying but he's really talking about being pushed out the birth canal. [Answer] Unfortunately, I think it's likely that the permanent death by suicide is going to happen after a surprisingly short number of cycles. From Bob's perspective (after one or two cycles) he always reincarnates after he dies. That's a big problem, because there are quite a few scenarios in which Bob is likely to say something along the lines of "You know, I think I want to move on to the next one." As early as the life of his second reincarnation, if Bob becomes plagued by serious illness or even just the unpleasantness of old age he's probably going to want to skip the suffering and move on. Loved ones may weigh him down at first, but after he's been through a few reincarnations he's already going to be developing a very different perspective on human relationships. Bob may also decide that he got a bad roll on his spawn point. After living a couple of cushy lives in the US or Europe, Bob might not be too pleased about being born into an impoverished village in Sierra Leone. Why struggle through all of that when he could slit his wrists before the age of ten and try again? With no one there to tell Bob the rules, suicide just looks like a reincarnation button that he has control of. Sadly, once he's tried it once, it's all over. [Answer] I'm going to assume that in Bob's first life, he's pretty average. He makes an average amount of money, but he never learns anything super special yet. The first time he reincarnates, his parents and other people might think that he's a little crazy, but also a child genius. Bob probably wouldn't know what was going on either. He would grow up having memories that he's probably been told aren't true. He would gain more knowledge about things he never knew about or new technologies that weren't around in his previous lifetime. The second time he reincarnates is when things start to get very interesting. He'll probably realize now that he has some sort of special power where he reincarnates after he dies. In this lifetime, he would start digging more into his past. The people he knows will probably also start to believe them, because he can point them to people he used to know, and tell them things that it would be impossible for him to know without having experienced it. Obviously, people would still be skeptical, but his story would probably at least go on the news. In his fourth lifetime, even more people would find out about Bob. He would also start experimenting more and more. In this life, or possibly the next, he would probably commit suicide, just to see what happens. I also think that the government would find out about him and try to find him and use him for good. At this point, Bob can take one of three paths: # Good Bob Bob knows he has this special power, and he wants to use it for good. He has forever to learn and make the world a better place. He can dedicate different lifetimes to learn about different topics, like Business, Computers, Fine Arts, etc. He would become the smartest person on the planet and he would change the world, and also become super rich. He would become a celebrity and whenever he died, people would be wondering who would be the lucky parents 9 months later. He lives a bunch of happy lives forever and ever. The End. # Government Bob In this path, the government takes Bob and uses him for their benefit. He would still probably change the world, just not as clearly. In this path, he will either make the government better. And live a similar life to Change the World Bob or he would become depressed and sad and become like Bad Bob (next path). # Bad Bob In this path, Bob realizes that his power is actually a curse. He becomes depressed and sad. He probably will start not telling people that he's *the* Bob. He also will commit suicide in most of his lives as early as he can. When he doesn't commit suicide, he's probably getting revenge, whether it's on someone who did something bad to him in a previous life (maybe he was abused or murdered before), or the government, because he used to be Government Bob. He will still also change the world as Bad Bob, because he is still a genius, but he's uses his intelligence for bad instead of for good. Now, instead of being a celebrity, he's become a government target. But that doesn't matter to him, because he will never die. [Answer] **Rich Bob** Bob, assuming he has a modicum of curiosity and drive, is going to become hilariously rich. Once he gets his first "good spawn", he picks a trade and does that for his life. Pays well enough, and there's few places in the world that someone who's handy with tools isn't going to do reasonably well (especially if they can become "naturally gifted" as a youth). (Military service would also be a good skillset to pick up early) After that, on a bad spawn he relies on his existing skills, on a good spawn he picks up new skills to help in later lives. Wealth transfer is a small problem, but that entirely depends on what you're planning to do. Given that after a few gos you're likely to be fluent in multiple languages, have skills (and presumably maturity) far beyond your age? You're likely to never be working McDonald's - even if you end up in the poorer parts of the world, I'd put good odds on you managing to make a life for yourself. On the other hand, if you've racked up a solid nest egg? Numbered bank account would be a good way to forward funds to your next life (I'm not 100% on the details, but a quick Google seems to suggest that once the account is set up that only the password is required to access it - perfect when you're not going to quite be yourself when it's time to withdraw, y'know?) If you're willing to let other people into the secret, you also have some options regarding trusts or other financial shenanigans. That seems in "exercise for the reader" territory, though. **Problems (or at least assumptions)** Having your memories doesn't necessarily guarantee that you have *complete* memories. So it's entirely possible that you're going to start forgetting things that you-a-few-generations learned. We're also assuming that Bob here is reasonably bright, and able to learn and retain many things given time. If you're in a situation where you don't have the opportunity to use a skill, you're very likely to lose it. The government (or other "shadowy conspiracy") angle is interesting. If you know that Bob respawns, presuming that you know when he dies and sufficient resources, you might actually be able to track down the two-year old respawn version. In that case, life might be a lot easier, since your followers/masters will presumably pick you up in the BobJet and take you back to the BobMansion (with varying amounts of shenanigans to make you a legal citizen, give you an identity, etc etc.) An interesting side question of this is "why?" - other than being a living historian, you're not particularly valuable. Best I can think of is that you-as-respawner are considered valuable, like the Dali Llama or similar - but then *you* aren't rich or possibly terribly powerful either. [Answer] My first thought was along the lines of Avernium's answer. But let's pretend he escapes the governments and corporations who would take advantage of him and he gets a few bodies to get the hang of things. From here, there really wouldn't be a lot that makes Bob special. He would have more time to learn new activities, and he would likely be better at understanding different viewpoints because of being forced to live in different environments. As long as he could figure out how to transfer wealth from body to body, he would get progressively richer, and could potentially gain a lot of power. But he's still one man, and no amount of past experience is going to let him foresee the future or invent free energy or anything. Also, there's a limit to how much a human brain can remember. After a few lifetimes (perhaps less), he would reach that limit. He would start forgetting details about past lives to make room for current information. Some stuff, like how many lives he'd lived, would be easier to remember because it would get constantly refreshed. But he would basically just be 300 years old or something, with a rolling timeline. He could spend a couple centuries getting really good at one thing, or he could branch out and be reasonably good at several things, but he wouldn't be able to become a master of all disciplines because time spent perfecting one activity would cause him to lose touch of others. Further, because technology and society is constantly changing, even if he could perfectly remember four lifetimes ago, knowing how to operate machinery from 1900 is going to be of little practical use. Even his use as a historian would be sketchy. He's still basically human, so we can't trust his "I was there!" word over the scores of journalists who took pictures and wrote accounts from multiple viewpoints. I do like the "god" idea though. If he could convince people he was reincarnating, he could create a religion around himself. He could give certain high priests in his religion little pieces of information that only he would know, then once he popped out in the new body, contact his religion so they could safely collect him. He wouldn't need to do anything special. Enough people would believe he was special without any kind of demonstration. Then he could be perpetually wealthy, have friends or lovers when he wanted, be left alone when he didn't, and have a baseline to keep his normalcy between bodies. Without special powers, the religion probably wouldn't make it past a cult in size, so he's unlikely to take over the world. Still, if he came back with different racial characteristics each time, it might be easier to teach tolerance and openness, which could allow his religion to flourish. [Answer] I know the answer to this all too well. I've seen things.....things that no one should ever have to know. All human activities are social activities whether it be economics, politics, warfare....it just doesn't matter. A social person 10,000 years ago will be equally successful today. Over many lifetimes, Bob became insanely expert at social interactions allowing him to manipulate people, situations and relationships to a degree none of you can comprehend. He takes over organizations, becomes the richest person on the planet and holds overwhelming power. He has arranged for his future incarnations to take over at the earliest possible age. Where he was born or into what circumstance will make no difference. All he has needed to do is arrange for some organization or trusted agent to be ready to acknowledge him when he appears. Who would decline a spot to be a personal assistant to such power - to share and bask in that power! Humans readily submit to power as part of their condition and give their unwavering loyalty. Any who would dare oppose Bob will be destroyed, along with their families, in the next decade. Who would risk it! He is a expert martial artist in most disciplines, master communicator, politician, engineer, scientist, detective, medical doctor, psychologist, CEO, sharpshooter, knife and sword master, chemist, master of disguise, storyteller, merchant, priest/pastor, mountain man, play-write, voice actor, strategist and tactician. He can kill with pressure points at a touch. Such things never really change over time and place. How many ancient books of knowledge are still studied today? (Sun Tzu, et al) Bob will be able to foretell the future. He will have knowledge, first hand and in detail, of times, places and events, spanning centuries and with such a complete basket of knowledge it will be child's play to map paths into the future of social interactions. History repeats because human behavior repeats. Bob will be supernatural. He will die and rise from the grave again and again. Best of all, he can PROVE he is immortal - a deity. Bob will be a god, a despot and a tyrant. He will be the Abomination. Heed my warnings! [Answer] I think that Bob's memory would be as much a hindrance as it would be a help. While many of us who have reached a certain age wish that we could live our lives over knowing what we know now - Bob isn't getting that chance. He's living a new life each time. Different circumstances, different cultures, different technologies and even as a different sex. He's going to be lumbered with memories of lost loves and lost loved ones. If you've lost one or both of your parents (or worse, your children) you'll know how bad that is. How is Bob going to feel when he loses his second set, or third, or fourth, etc. How will he react to that in the long term, will he give up on relationships altogether? Bob's a normal guy (at least the first time around) so he'll have hang-ups and prejudices just like everyone else. These will be part of who he is and form a strong part of his memories and will consequently carry over into his subsequent lives. How will he cope if, for example, he's deeply homophobic and in his next life he's a woman? In his memories of himself, he's a man; a man who thinks that marriage is for a man and a woman. So as a woman is he going to date a man or a woman? Or will he just find the whole thing so distasteful that he opts out altogether? Maybe he's originally born Jewish and lives a long devout life as a Jew only to find that in his next life he's born into a Palestinian family on the West bank. How will he and his new family react to that? While his beliefs might not be that extreme, over multiple lives Bob's going to hit situations that make him/her very uncomfortable. Not only that but, as we've seen with homophobia, what was once common and acceptable is now, publicly at least, unacceptable. So Bob may find that his personal memories are actually an unwelcome and possibly detrimental burden. Even worse will be if he has an almost ideal life, every one he lives after that will be compared against it and found wanting. Just imagine pining over something that happened to you centuries before which you repeatedly fail to match. And finally on a slightly [squicky](http://tvtropes.org/pmwiki/pmwiki.php/Main/Squick) note; Bob's going to have to start being careful, after a few decades or centuries, if he's going to avoid dating any of his own descendants. Especially if he feels drawn back to a particular place that he considers home. [Answer] There are several skills that Bob can pick up, but the most obvious 2 are science, and rhetoric. Both are incredibly valuable skills, but it turns out that it's the second one that is massive. ## Abilities **Research knowledge** Bob will have plenty of opportunities for academic careers, and he will have access to higher education many times. It's likely that bob will have a good understanding of many fields, but I think it's unlikely that he can use his ability to contribute significant cutting edge research. People do forget things, and people change their interests. This makes it unlikely that he'll commit to cutting edge research, except maybe to acquire some military high tech research he needs for an evil mastermind plot. **Jack of all trades** By going through various education systems, and also by having parents that have many fundamentally different professions, Bob will be at least somewhat familiar with a vast selection of crafts. **Ability to manipulate** If Bob has his memories back and meets up with his playmates at preschool, his social interactions will work very differently from those of normal young children. He will know and understand their intentions far better than they do, and it will be extremely tempting to try to manipulate them to learn more about social interactions. This will grant him the skill to read humans and to motivate them according to his wishes, which is incredibly valuable, and can be used in every culture and every reincarnation. And this skill will become stronger every time he reincarnates again. Rhetoric was already a huge thing with the Romans over 2000 years ago, and who knows how many 10'000 years before that. And in all that time the skill has hardly changed. If Bob wants to, he can reliably create a cult with any number of followers. **Multicultural** It will be very unlikely that Bob will be racist after the first couple reincarnations. He'll have a good understanding of cultures, a profound knowledge of history, and an unmatched knowledge of languages. **Wealth** No matter where Bob reincarnates, there will be a point in time where he will always have access to some amount of wealth as soon as he's able to travel. Enough to get him somewhere where he has access to more wealth. A couple reincarnations in, he's hidden hundreds of stashes with gold, silver, and jewelry all over the world. This starting capital and his ability to manipulate people, his knowledge of infinite crafts, and his fluency in many languages make him an unequaled trader who has no problems making money whatsoever. ## Conclusion With these skills, there are plenty of paths Bob can take. Remember he can play the long game, and his game is longer than that of anyone else. **1. Observer** Bob decides that all factions have their reasons for acting how they do and he isn't the one to decide who's right or wrong. Bob decides that he wants to play a neutral role and simply observe and document history, preserving it for future generations. He uses his talents at motivating people to set up a secret cult of followers that documents events as they really happened. there are many ways in which he can set things up in a way that he can rejoin them in most reincarnations without even revealing who he is. **2. Rule the world** Bob decides that the world needs his help, the flock needs a shepherd. He could intervene in a local dispute, but his skills would be wasted there. He needs to be at the top. Being the ruler of the world in an official capacity is a very hard thing to achieve, and even if Bob could reliably pull it off, he would lose much of his lifetime in each reincarnation getting there. A more reliable method is to infiltrate multiple intelligence services. It might take a few centuries, but he can use his skills at making friends and loyal followers to secure strong ties into intelligence services that last between reincarnations. The secretive nature of that business and written communications across communication lines secured by passcodes make it feasible for a 3 year old to be pulling the strings behind everything. This approach is the most likely to at some point draw the attention of one or more governments. If he gets caught he'll need to wait one lifetime during which he'll work a different angle, maybe a diplomatic career, after which everything about him will be forgotten and he can begin anew. **3. Armageddon** Bob has seen it all, and he has seen enough. Bob decides that humanity is not worth existing and he was given his gift to end humanity. His skills at manipulation and his conclusion that humanity is beyond saving convince him to end humanity by convincing them to destroy themselves, subconsciously hoping that they will manage to thwart his efforts. In one life he organizes an accidental US nuclear strike on Chernobyl, to start the war to end all wars. In the next life he becomes a successful businessman and works to convince the world that global warming isn't real. In another life he'll become a scientist that tries to convince the world that antimatter reactors are perfectly safe clean energy. [Answer] This scenario is very close to the premise in [Octavia Butler's Patternist Series](https://en.wikipedia.org/wiki/Patternist_series). SPOILER ALERT: > > Breeding humans becomes accessible to someone with the lifespan of possibly tens of thousands of years. I would argue that this is probably the most powerful, lasting 'influence' on humans, especially since we would probably not be able to notice long-term breeding programs, we just don't have the attention span, or cultural institutions with a long-term view to notice, and plenty of religious beliefs that encourage ignorance regarding evolution. And the effects of a breeding program can be profound in ways that is hard for us to imagine, since we're so 'in the moment' even if that 'moment' is 70 years, that is a blink in the eye in evolutionary terms. In that series, a human (Doro) acquired the ability to 'jump' into a nearby human. This 'jumping' was intentional, but was also triggered when his current body was killed, so he couldn't really die. He took over the mind/body completely and obliterated the host mind. He becomes quite inhuman, cold, since humans are basically disposable to him. Over time, he begins to breed humans in different places around the world, trying to create something like himself. This implies that he becomes quite lonely, although he is so unlike normal humans after a few thousand years that it is hard to imagine him admitting something like that. 'Wild Seed' is particularly relevant, since once of his breeding projects produces a woman who is likely also immortal, but in a different way, and this is the first time he interacts with a possible equal, or at least, someone who could understand him. > > > [Answer] I would like to focus my answer on one of the problems mentioned by others: namely that Bob has an overwhelmingly high probability of being born poor. The answer to this is simple. By being born with all the knowledge of all his previous incarnations, all that is necessary to bypass this problem is to have one lifetime in which he amasses enough wealth to control an organization of people, such as a corporation, which he founds. And with multiple lives of experience this ability to amass wealth should increase, as all the trial and error in previous lives is carried forward each time. The organization will be laid out with stipulations of how his succession works. Nobody need know anything of Bob's secret, and nobody need know all the pieces of the puzzle, ensuring that only his reincarnated self can claim the lead next. Furthermore, Bob can have "decoy" successors whose appearances are not well known, to give the appearance that he is grooming his replacement among a list of potential candidates, to eliminate any suspicion of some unknown suddenly showing up. And furthermore, precautions can be take to deal with the fact that after Bob's death there may be a delay of 18 years or more before his next self takes over. There may in fact be layers of protocols involved by which other people act as trustees or temporary stewards of various aspects of the organization until all the pieces for the next true successor fall into place. Now when Bob is reborn, there is naturally the annoyance of having to wait 18 years to reclaim his organization. But no matter where Bob is born, in what conditions, if Bob has any kind of cleverness he will realize that he can just play dumb, not letting on to his real nature, and wait for the opportunity to make his way across the world to wherever his base is. I would argue this is totally doable for any person in the world - given the clear goal and payoff in sight - no matter what their situation and upbringing - one can play along with their environment for the first 15-16 years, there are many ways they can find to make a one-time relocation to another place in the world, whether it is joining a merchant marine, or stowing away, or even just hiking if on the same continent. Once Bob is able to grow his organization enough, then it is a simple matter of building more bases, one on each continent at least, so that he can eliminate the need to cross an ocean at the start of every life time. To summarize, the key pieces are: * accumulation of wealth and self-succession: Bob has to use his knowledge to gain some kind of competitive advantage which will allow him to set himself up to retain what he has worked for over all his lives. * secrecy: nobody knows Bob's secret, and what they do need to know is distributed so that no one person or even group of people that know each other could get together to take over [Answer] Bob will **not** be poor, all the time. He will bury items of value from the lives when he was not poor and dig them up as antiques in a later life. Bob will become an expert in antiquities. Knowing where many ancient cities lay from having live there, he will be a great grave robber - err, archaeologist. Bob will master all major languages, hence be useful as a translator, interpreter and guide. Bob will eventually master mathematics, science, and every musical instrument. Bob is likely to become pro-life after the hundredth time he is aborted. Bob will have a lot of family obligations. He can make use of knowledge from the many places he has lived to form trading coalitions. He will create passwords and leave them with his heirs so that he may reappear and resume his leadership role. He will use his wealth to benefit his large extended family. Bob will occasionally be a fierce and courageous military leader. If he is killed, his bravery will embolden his followers. Bob will have started a major religion, only to abandon it because being revered as a God and living in a temple all day is boring. Bob will not commit suicide, because there is always death by cop to fall back on. When Bob has a physical disability, he will inspire millions by his fortitude. Most importantly, Bob will work very hard at preserving his reputation, because if his is ruined, he will pay a bigger price than anyone else in existence. [Answer] \*\*Wheel pottery in the Americas \*\* For the first hundred years, it should not be an actual being, just as a "racial memory" that keeps accumulating. I thing it would be the so because of the very different shapes s/he will have in each reincarnation: sex, complexion, skin color, native language; by the time B has being reincarnated enough to understand the phenomena, the racial memory view had been deeply adhered, and it would take a long time to substitute it by a prolonged *sense of self*. Besides, this view of memory avoids problems of compatibility with the current grown state: adolescence, adulthood, etc. During the hunter-gatherer phase, this memory should be a good help to identify foods, drugs, etc. Of course it only helps a group each time, and so it should not be a big impact. As for innovations, they move fast; it could happen to be born in a tribe that has not learnt yet about bow and arrows, but it is unlikely. Things become more interesting after the Bering cross. I would bet that the pottery wheel would be common in America too, and we could have some peculiar relationships between writing scripts here and there. During the early civilizations, a child with innate memory for scripting -and hopefully elementary math- would be appreciated, even if born in a poor family... with time, s/he had developed at least an instinct to hide from and to be found by the powerful people. Generically, willing or not, Bob will contribute to cultural cross-fertilization, and this will surely the age of more impact in the humanity. By that time, with a population already of about 100 millions, the probability of being born twice in the same civilization is low, and no big differences happen; there is even a non-negligible probability of being born as Aboriginal Australian, effectively ruining some of their cultural isolation. But as India and China start to show efficiency in human grown, Bob is going to pass more time as Indian or Chinese that as native american. This could help to keep fortune from one to the next generation; and some knowledge of the world could allow to return to a known place if wished. But on other hand, to be born in the same civilization becomes a bit of disappointment. No cultural cross-fertilization anymore, just progress. I think that it is here where the split of @michaelpri answer can happen: private or public person, good or bad. I have taken some time compared with the "4th lifetime" idea :-) [Answer] I want to point out one thing that everybody missed. With our current technology, there is a serious threat to Bob - COMA. If Bob is ever captured by government, or anybody serious really, they can put him permanently in state of coma or hibernation, effectively rendering him useless. He can't do anything, because he's not contious, but he can't be reborn, because he's not really dead. It then becomes an interesting question of keeping him in this state for generations, and becoming a myth, but that's for another topic. [Answer] As Green and others have pointed out, a lot of his cycles would be in very poor areas with very poor lives. But I don't think he'd be poor for very long. A lot of this depends on when in the past his cycles started, but seeing as it keeps happening over and over and over, and he remembers everything, he'd (relatively) quickly pick things up, even without an education. He could endenture himself to a merchant, money lender, or anyone else that could teach him new skills. Even if he went in and offered to be a slave for life if the person would train him he could learn new stuff. And each cycle he would start out a little higher on the ladder. "Let me work for you. I know how to read and do sums, I could help you make a lot of money." During female cycles she'd be at a slight disadvantage for most of history, except that the memories of being a man could help a bit, mostly as an extra edge in manipulating men. But also because of her skills and knowledge she'd be able to present herself as a good catch for marriage, and potentially get a higher social standing than birth would allow. Eventually he'd be able to become very wealthy, if he figured out how to cache stuff for himself in the future. It might be saving and burying some of his income each lifetime. Or he could take it from others; hold up a drug den, get a lot of money, maybe convert it to something liquid like gold or gems, hide it somewhere really secure, and then repeat. Eventually the bad guys catch up to him and kill him, and he starts over. He might do this over several cycles all around the world. As soon as he's able (financially) he travels to the location of his caches and picks them up, consolidating the wealth into a single pool. And eventually when banking becomes a thing he'd be able to set up a numbered account in some tax haven and get easier access to his money. [Answer] Easy question. Bob has reasonnable chances to discover the game of Go / Baduk / Weiqi. Once he does, he just have to play until the end of time. Since he has unlimited time to study the game, he'll become one of the strongest player and eventually find the 'Hand of God'. He even could tell his story to other people and prove it, since each go player has a unique style of play pros could recognize him thanks to his behaviour on the Goban. [Answer] I'm pretty certain that after a few regenerations Bob would start to look for a religious reason as to why this was happening to him. It wouldn't take much effort to realise he was actually the [Dalai Lama](https://en.wikipedia.org/wiki/Dalai_Lama#Searching_for_the_reincarnation). He may not be born in Tibet every time - so he may have difficulty convincing the populace, however as the current Lama is in exile, then it wouldn't be that difficult. [Answer] His first life is average. After becoming aware of himself after the first reborn cycle I would expect him to redo past regrets or try out missed opportunities. But now the problem starts. What kind of affinity does Bob has? What kind of will strength does he posses? Just because he has all the time of the world does not mean he has the urge to care. He could live his life and just live for the pleasure. If he is horrible at Math, why would it be better at the next cycle? If he uses 50 years of his life to understand string theory, it's not a free win to make a break through discovery. With the changes in technology, even past knowledge becomes quite fast useless. He could pick professions up as a hobby. He could be wealthy with safe spots of past money. But I think ultimately the only thing that Bob can reach is personal pleasure and a huge worldview. [Answer] Well, some believe that the non-persistent memory version of this is actually happening, except maybe the suicide part, but maybe even that(!). This is a highly theoretical game, but let's add the persistent memory to the picture. What if you would actually know that you are being reborn after every death. I think that would actually uncover a layer of reality that would make you realize that the existence is not a random pile of events, but there is a higher reason to it. I think the answer boils down to Bob's capacity to realize this in time, before he willingly takes his life. I think if he realizes this in time, it inevitably leads to Bob becoming Good Bob, maybe after a few lifetimes of struggling with trying to play around and searching answers to irrelevant questions (why, why me, what if, who else, how much, etc.) BTW, Just for completeness, I think if there is no higher meaning added to the game, the question does not make sense, because reincarnation does not make sense either. [Answer] **The Ever Learning Bob** Bob would not be much different after about the third time around then anyone else. Sure he has some extra memories, but can you remember *all* the specifics from when you were a kid? Now multiply that times 3. Bob's memories will, like anyone else, fade with time and all that will be remembered is the "important" or "traumatic". The rest will be just gone. In addition as times change, and tech changes, Bob will not have any more of an idea of how to do a thing then a non-bob. The only real benefit that Bob would have is the ability to "pick up" on certain things faster. Bob might be an excellent fisher, because while he can't remember clearly that 10 lives ago ho was a pro fisher, he will have a kind of aptitude for it. Like ridding a bike. You may not have done it in years, and you may not remember the specifics, but you will remember very quickly and your riding skill will improve quickly. Still the first time you get on a bike in years your liable to fall over or at least teeter. As a down side, though, every body would be different. So while his mind remembers walking, and he might pick it up younger then most, he still will have to adapt to his new body and it's limitations. **The Journal** I would expect Bob, after going through the process a few times would start to be annoyed by not being able to remember things like his first love's name. This would lead Bob to keep a journal. The journal would be a kind of constant in his lives. Storing and keeping the journal would be come a kind of obsession, as would recovering it in each new life. [Answer] You'll basically have a watered-down version of the Avatar from A:TLA. This seems like a pretty pointless thing to do unless you give him powers, and if you do you'll kind of be ripping that show off. The only real purpose I could see humanity having for him is for him to be the ultimate historian, since he remembers basically everything from the dawn of time. [Answer] This is an interesting question. The narrative possibilities are only limited to your imagination, which is a difficult place to create from, so here are some potential restrictions that reality might impose and that might help us shape our understanding of his conflict and what sorts of impact might be possible. **How would Bob's kinship with humanity be altered by the cumulative effects of his lifespan?** While we don't often think about it, the specter of death invariably shapes all of our lives. It's inevitability forces us to have some sort of opinion on it, and that opinion shapes many of the decisions we make and even the way we interact with others. A person who doesn't have this pressure would have a tremendously altered view of existence. He may have difficulty really connecting with other people and his mounting idiosyncrasies may make it difficult for people to understand him too. After a few lifetimes, he may be regarded as insane, disturbed or possessed based on how he decides to interact with people, especially if he too greatly defies society's expectations in his youth. If he has possession of his adult memories and perspective as a child, it would be very difficult and possibly maddening to keep up the charade of immaturity as a young boy. **How would Bob desire to affect the world?** Bob's understanding of what is meaningful would be radically altered by this experience. You'd like to think he could use his accumulated knowledge and experience to practice cozying up to political leaders in various contexts and persuading them to change until he is able have tremendous influence over the world sort of like a real-world Gandalf. But what gives him this altruistic purpose? What motivates him to endure the hardship, defeat and pain associated with the work involved with this process? It seems likely that he would at least be tempted to continuously recluse himself in nature beset with a sort of nihilism or apathy, perhaps a path more similar to Radagast. He may find himself giving little concern to the petty priorities and temporal conflicts of other inhabitants of the planet who refuse to help themselves and whom he feels little to no kinship with or attachment to. **Would Bob really be a single person?** There is actually an interesting ongoing debate in transhumanist circles about the durability and elasticity of identity and personhood. In other words, it may be theoretically impossible to be the same 'person' for too long. The memories that define us get fuzzy as life carries on. Furthermore, the memories and lessons that are retained would be mangled via iterative reinterpretation as they are forced into one life context after another. Who Bob is in this life, for example, may not resemble at all who he was three lives ago. Would he be continually upgrading, maturing and improving his self? Or would he perhaps be more mutable and subject to his environment and external influences and experiences than we would perhaps like to imagine? How Bob is able to affect the world would likely hinge on how he is able to contend with these challenging aspects of his condition in order to fulfill his character arc. [Answer] Since his immortality seems to be linked with the existence of mankind I will assume that he is living and reincarnating since the first humans appeared. So he will have 100.000 years of experience as a hunter and killer. In all prehistoric tribes he will be the great hunter and shaman and will be honored above all. Legends and myths will be built around the eternal man. By the time farming begins he will know how to hunt anything and kill anything. Millenia of dealing with liars and traitors will make almost impossible to lie to him and he will be an incredibly good liar. Things will get complicated when farming begins because he will keep reincarnating in dirt farmers in Mesopotamia, Egypt, India and China due to much greater amout of births in these places. He can use his 100.000 years knowledge of human nature to either climb form the peasant rank to the priesthood or to become a criminal. Many reincarnations doing that means that he will be very good at that and his exploits will be the origin of many legends and myths. A religion may form around the child with the wisdom of the holy child and the priest may keep looking for the next reincarnation as part of religion. In the modern world he will be the supreme mafia boss and assassin, every time he reborns, he may try to climb from the rags to the riches and, since he is doing this forever he will be very good. Let's say that in 1900 he born in a poor italian family in the US. He will climb to the top of the mafia, then get killed by enemies somehow. Then he reborns as a poor chinese farmer in 1950, emigrates to the US, rebuilds a criminal empire, kills the children of his enemies and is, once again, by 1990 at the top of the criminal underworld. ]

[Question] [ It is the near future and insectoid aliens pass our planet. They are shocked and dismayed to find that disgusting fleshy creatures seem to be in charge. Using their alien technology they imbue all of the insects on earth with swarm intelligence. This creates one enormous distributed super intelligent being. The terrestrial insects realise that humans have for centuries been destroying them on a whim, treating them as pests or merely exploiting them. They decide to wage war. > > Recent figures indicate that there are more than 200 million insects > for each human on the planet. An article in The New York Times claimed > that the world holds 300 pounds of insects for every pound of > humans. [Lists of organisms by population](https://en.wikipedia.org/wiki/Lists_of_organisms_by_population) > > > **Question** Given that each of us is outweighed 300 times, they could simply swarm over us and suffocate us. We have only our present day technology and certainly no magic, nor understanding of the alien technology or even what happened. Can the human race survive? With no notice that this was going to happen, is there any way of fighting back? [Answer] ## Can the human race survive? No. We're too dependent on them for our survival. --- An open attack would hurt them - we'd just insecticide them. That's not a good strategic move by the bugs. Not a good strategic move by us either, but the choice is stand idly by and get suffocated by a million crawly feet, or destroy the ecology and *possibly* survive. The insects would kill us by not servicing the food chain... correction... by not servicing *our* food chain. They'd starve us out of existence. To hurry the process along, they'd actively start eating our food reserves at the same time. Locusts will eat our crops. Mosquitoes drinking grazing livestock dry. Bees stop pollinating flowers. Humanity most certainly would notice something funky is going on. Food shortages. Price hikes. Economic instability. We'd be too busy trying to fill our bellies to unite and fight the insect-war. To make matters worse, the bug hive-mind could play us against ourselves. For any two adjoining countries that *really* don't like each other, starve one but not the other. Wars will be waged out of desperation(read:hunger), pre-emptive action, or opportunistic attempts to get rid of people you don't like. Once the governments have collapsed, there will be no organised resistance to the insect war. *This* is when they smother us. [Answer] ## **Game Over, Humans Lose** Our countermeasures against insects works because they aren't coordinated. Much of what we do to prevent exposure of our bodies, food and assets works against specific pests. Screens over doors and windows work against mosquitos and other biting insects. Pesticides prevent crop destruction. But, all of the things that we defend against can be undermined by a determined effort by a combination of species. (I'm going to focus my efforts on North American ecologies because those are the ones I know best.) ## **Bees** The easiest will be if the bees just stop pollinating crops. Without pollination, the world's food supply collapses in a matter of years. Perhaps sooner, if other insects and contaminate and destroy existing food supplies. ## **Termites** A great deal of the protection that we enjoy against insects comes from our buildings, specifically about [128 million](http://continuingeducation.construction.com/article.phphttp://continuingeducation.construction.com/article.php?L=5&C=645) wood-frame homes. Wood frame structures are ripe for attack by termites. Termites driven by a coordinating intelligence could avoid the bait and traps that we already place and focus their attacks on the structural wood. Attacks like this will require several months to execute so it may take a while before we humans see any results. ## **Flying insects** There are bees, wasps, and hornets everywhere. Generally they keep to themselves but if directed they could make an impressive area denial weapon. Attacking and stinging people as they leave their homes before they can reach their cars. Children will be kept indoors and people will leave only when absolutely necessary. Food shortages will start for people who go food shopping every day or every other day. Mosquitoes are also an effective area denial weapon. Any flying insect, if there are enough of them can plug up the air intakes for automobiles or tractor trailers. Cleaning those filters is annoying and slows down the movement of goods. ## **Ants** Ants are capable of getting into very tightly enclosed places and chewing on things that shouldn't be chewed on. They are also capable of moving large quantities of earth, so it's possible that they could actually undermine the foundations of buildings. Attacks like this would still take time but perhaps not as much as expected. ## **Direct Attacks on Humans** Many insects have a painful or poisonous bite. With a swarm of attacks on a human, particularly the elderly or very young, biting insects can cause extreme illness or death. Ants can strip human bodies down to the bone. Insects may not be able to kill every person but they could destroy infrastructure and crops that would prevent humans from eating. [Answer] There are some areas of the world in which most insects would have a hard time surviving -- deserts and near the poles. Though of course in the sub-artic regions midges seem to do pretty well every summer. A few humans could probably hold out in the arctic sustained by fishing etc. (i.e. traditional Inuit would be OK). There might be large enough oases in the desert to support agriculture (not insect-pollinated of course) while still being far enough from more hospitable regions to provide a barrier to significant swarms. [Answer] Get them fighting eachother. Seriously, this is the kind of "what if" that doesn't go well for the question in search of answers. You have created an enemy that is: * Far smarter than us * Far stronger than us * Out masses us by several orders of magnitude * Hates us * Has no weak point, because it is so diffused * Already has control of the entire globe These sorts of bad guys always pose ill for the question being asked. Taking on the infinitely strong bad guy never seems to work, short of asking Morgan Fre--- I mean "God" for a reset. The easiest way to solve this problem is to simply leave the humans out of the equation. Whatever the solution is, over 99.9% of it is going to need to be implemented by the only entity that matters: the bugs. We could *almost* ignore the humans entirely and get to our final result. The humans can only pull strings in the background. Our best bet is to get our special forces hats on. Instead of trying to combat the bugs, we need to turn them against each other. The special forces are trained to train others to fight... we'll need to do that here. Step 1: Learn whatever language the bugs know. They clearly have one, because they're communicating. We're going to need to learn to talk Step 2: Reawaken whatever primal feuds we can manage. The most important is probably the feud between ants and termites. As long as they are infighting, we might stand a chance. Step 3: Spiders are scary. People are scared of spiders. Hmm... there probably should be instructions in step 3, but it seemed more apropos to point out that a reasonable portion of the human population is going to freak the `bleep` out in the first 2 hours of the assault. We might want to stock up on Thorazine to subdue the arachnaphobic. I'm just saying. [Answer] Well our bug bombs are pretty effective. We have chemicals that are extremely deadly and can be deployed from the air, from canisters or even by hand. The initial attack would cause trouble. Assume massive human losses at the start. The bugs will have complications crossing the oceans, giving humans time to prepare. Once the pest killing machine gets rolling, the bugs don't really stand up very well. If these bug aliens didn't interfere, then we would probably eliminate the mass without need for nukes or what have you. Even standard bombs and missiles would cause tons of damage anyway, the shock waves alone would nearly triple their potential if not more. From there, the bigger problem is all the bugs are gone. The food chain is shot, animals die that rely on them for food. A great many species would also disappear or at least be crippled from the event. Maybe this was the aliens goal all along. [Answer] # Neither side wins The reason why we haven't exterminated insects already is because they are needed for just about everything. They are a crucial part of the ecosystem as well. Let's say they all move to a portion of the world to wipe out a specific target: humans. They still need to eat and survive. It would be a battle of attrition against themselves because they would eat their entire food supply at a much faster rate than normal. They can't just not eat. They are small and can't store much energy. So they eat and devour everything in their swarming, then the land turns to desert. Then they move to another area, where they repeat the process, until they have cornered themselves and there is nothing to eat, no shade, and masses of insects die. The ecosystem crashes and everything dies, just because they grouped together. --- Some insects eat other insects. like the Japanese Hornet ([#1 on this list](http://listverse.com/2010/08/09/10-formidable-predatory-insects/) I hope I never see one of these) [](https://i.stack.imgur.com/rc5ow.jpg) Those bugs can't just stop and say "Hey I am not going to eat you, because we are fighting these huge humans". Insects multiply faster than humans, I am sure that it will cause an increase in these types of insects as well, just to balance out the amount of insects in the area. --- [Answer] The way you have described it I guess.. **We Lose.** *But - Say we assume 'super intelligent being' is comparatively on par with our intelligence in the insect world and we have a fair fight.* **Then, We win. We adapt.** Why? * We already know their weaknesses - We have already have many ways of killing insects and protecting ourselves from them; fire, pesticide, weight, air filters, water filters, virally etc. * We already have the weapons and technology - including pest control experts. * We have opposable thumbs - we can build and operate stuff to work for us. * We can turn insects into food if required. We even have mind control. Search for cockroach. There is an app for it. [Answer] I don't think there is easy way to say who win this. From one side, insects outnumbered us, but from other hand there are various type of clothing which protects us from any insects (at least in theory). In majority of homes, there are plenty insect killers sprays or other anti-insects weapons. Insects, such as locust could attack our crops, but this is real threat even without super intelligent swarm mind. Locust is constantly under monitoring, its population is under control. So people wont't be completely defenseless in this war. But from other hand, super intelligent mind having under control every insect, this is huge advantage for team Insect. Insects can win this war, but it has to be blitzkrieg. They has to win in first attack, because if humans will reorganize and strike back, insects will lose. In long run, humans have technology which allow them to completely eradicate all insects. Would be a Pyrrhic victory, it is different story. [Answer] # The insects will definitely win * Pesticides are of no use: they would work initially but insects like ants, mosquitoes and cockroaches get used to them too quickly (as a proof of that, they still infest houses). * They can infiltrate in computers and machine and tamper them (the term "bug" for errors in IT comes actually from the fact a moth short-circuited one of the first calculator) * They can spread diseases like malaria and [black plague](http://www.rt.com/usa/247257-arizona-prairie-dogs-fleas-plague/) * Many of them are so tiny you don't even know they are there. By the time you found them it's too late. * I read a study many years ago stating that scorpions and cockroaches would [survive a nuclear holocaust](http://www.theguardian.com/notesandqueries/query/0,5753,-2251,00.html) ]

[Question] [ There are a lot of answers on Worldbuilding about how to destroy planets - just as an example - and they seem to be the method of choice for many people intent on destroying the world. My objection to this is that this is extremely difficult; moving a massive, orbiting planet isn't like picking up a marble and throwing it. What is a feasible method to move a planet (gas giant or Earth-like; I'm interested in both) from an orbit around a star to anywhere else in the galaxy? [Stellar engines](https://en.wikipedia.org/wiki/Stellar_engine) exist, but they require . . . well, stars. I only want to move the planet, not its star. I've considered things like creating large scale rockets - really big ones - and attaching them to the planet, but something tells me that this isn't realistic. In fact, using any sort of conventional propulsion on such a scale doesn't seem feasible. So, how can I move a planet? Please, try to use some science here, although keep in mind that I'm asking from the perspective of a [Kardashev Type II](https://en.wikipedia.org/wiki/Kardashev_scale "Kardashev Type II civilization") civilization. I don't have any timescale in mind; I'll go with what works. [Answer] The essence of moving a planet is just the same as altering the trajectory of a space probe - just on a larger scale. When a probe (say New Horizons) flies by Jupiter, [it steals some of Jupiter's orbital velocity](http://www.nasa.gov/mission_pages/newhorizons/news/jupiter_flyby.html). It is also possible to have the probe be on the other side of Jupiter and donate some of its velocity to the planet to slow the probe down. With a sufficiently massive planetoid, one could have the planetoid donate energy. As described in [gravity assist](http://www.planetary.org/blogs/guest-blogs/2013/20130926-gravity-assist.html) by the planetary society there are a number of options. In particular, the one in option A, B, C, and D: [](https://i.stack.imgur.com/Ur4KP.gif) In these cases the less massive object goes in front of the planet and slows down after the encounter. That slowing down transfers momentum to the planet and speeds the planet up. The faster the orbit, the further it moves from the sun. With appropriate timing of repeated encounters it would be possible to use an asteroid or similar object to transfer momentum from Jupiter (it has 1000x more than the Earth ([reference](http://www.zipcon.net/~swhite/docs/astronomy/Angular_Momentum.html))). It should be noted that this isn't something that can be done in a day, or year, or even century - but rather over the course of millennia. That said, it also doesn't require any fancy physics or technology. Just the right math and a lot of patience. As an aside, look at Nasa Trajectory Search ([example query](http://trajbrowser.arc.nasa.gov/traj_browser.php?maxMag=25&maxOCC=4&chk_target_list=on&target_list=Jupiter&mission_class=roundtrip&mission_type=flyby&LD1=2014&LD2=2040&maxDT=10.0&DTunit=yrs&maxDV=20&min=DV&wdw_width=-1&submit=Search#a_load_results)) to get an idea of how often such flyby opportunities occur with minimum additional orbital mechanics. Granted, this is intended for space probe missions as opposed to a flyby round trip - but it gives you an idea that for each Jupiter flyby its a 6 year round trip. [Answer] **Diplomacy: Befriend a level 3 or 4 civilization. If you get a level 3 civilization have them find a level 4. The level 4 people open a wormhole and bing, bang, boom you're there.** Your only real hope is to open a wormhole directly in the planet's orbit and connect it to the destination somehow. Anything else would take insanely long. Any towing beyond moving 1 orbit to another around the same star would likely kill the inhabitants, because as soon as you leave the habitable zone of the local star your planet will freeze. You would need fast transport to avoid your planet freezing, even if your planet has a molten core that will only last so long in the cold of space. Even if you do make it, your core is frozen and will take 100's of years to reheat if not more. Additionally, if the planet has a lot of water, massive earth quakes will occur as the water freezes in its, potentially, long journey to another solar system. You would have to harvest the energy the local sun to open the wormhole as the current theories say it requires vast amounts of energy. Otherwise a series of star trek like transports and relay stations to get it to the destination. A tractor beam, but it would require insane energy and the ship pulling even more. Then you would also have to tractor a part of the sun so your planet didn't freeze to death on the way. Assuming you could harness the hydrogen/helium directly energy might not be a problem. The problem is the bigger the chunk you need the more mass, the bigger it needs to be. [Answer] In *World out of Time*, Larry Niven explains it well. [](https://i.stack.imgur.com/hNNOJ.jpg) He had a motor in the atmosphere of one of the ice giants (I forget which) that shot the planet's atmosphere out to cause reaction. That planet was guided to pass the planet to be moved, nudging Earth with its slingshot effect. This pretty much destroyed the ice giant, but *carefully* moved Earth, intact. --- Note that the planets *did* move around, substantially, even switching order, ejecting some, dropping others into the sun, smashing some together. So why can't "nature" end up putting them where you wanted all along? My novel answer is **chaos**. Nudge small rocks using a small amount of energy. That influences larger rocks to nudge their orbits. The larger rocks influence still larger rocks, etc. You cause a dynamic instability, and through continued application of small changes, make it settle down the way you intended. [Answer] **TL;DR** Build a planet big space ship, move stuff with gravity of that ship, using star energy for propulsion solar sail like. Or by pressing on the planet. As reasons to move planet are not given, so are not defined approaches to do so. So I will pick few of possible solutions. Also it have to be noted, CII may have better ways to deal with that particular subject, if let's say [eLISA](https://en.wikipedia.org/wiki/Evolved_Laser_Interferometer_Space_Antenna) will lead to deeper understanding of gravity and CII may be able to manipulate that gravity which will make moving planets piece of cake, and alter all I have wrote. So my suggestion is rather like how our today civilization with CII energy capability's may deal with that. And I ensure you, gap by energy isn't such big deal actually(It's way much closer as usually people thinks), but difference how to use it may be like steam [arithmometer](https://en.wikipedia.org/wiki/Arithmometer) vs Top500. I feel like I can trow stones to Kardashev scale all nights. ## Today knowledge, Sun energy [Sun](http://nssdc.gsfc.nasa.gov/planetary/factsheet/sunfact.html) energy is a lot, but not too much actually * Power 3.828×1026 W Few numbers to represent it as kinetic energy, velocity mass, 1k=1000, 1kk=1'000'000 etc, [relativistic kinetic energy](https://en.wikipedia.org/wiki/Kinetic_energy#Relativistic_kinetic_energy_of_rigid_bodies) $E\_\text{k} = m \gamma c^2 - m c^2 = \frac{m c^2}{\sqrt{1 - v^2/c^2}} - m c^2$ * 1c, just energy mass conversion: 4.3kk tonne * 0.99c, 0.7kk t * 0.95c, 1.93kk t * 0.90c, 3.29kk t * 0.80c, 6.38kk t * 0.50c, 27.5kk t * 0.30c, 88.1kk t * 0.10c, 833kk t Not proud to write numbers, mostly for my personal reference, but as u may see from 0.9 and above u transport more energy than mass, and mass is just carrier for that energy. Even if we may send everything we have at the moment, in 5-10 minutes with resulting speed 0.1c, but compared to the planet, everything we have isn't so much. * 1km/s, 765e+18kg There comes difference, as result what we wish to accomplish, for which purpose we do it, etc. We are not equal interested in all 100+ elements we know, and from civilization stand point of view, importance may differ from value, we can't eat gold, but we happy to eat carbon based stuff, and as technology develops, no one can guarantee that technology valuable properties of gold will be so much important as it is now - it's subject of changes, but until we stay carbon based live, carbon will be important. Also, carbon-based technology, wonderful (atm) strength of [CNT](https://en.wikipedia.org/wiki/Carbon_nanotube) may be very important for future tech, specially for moving planet's projects. ## Option 1, take what you need, planets disassemble When it comes to specific elements, then definitely there is a reason to mess with whole planet, not necessary do that but if civilization do not have tech to fuse elements easily(this is rather knowledge challenge then energy challenge) it may have sense. But we have force, me not thinks, me dissemble planet, hugh hugh, rrr - besides it's fun, why not. Disassembly may be done in different ways evaporating by focusing light-energy on surface of planet (some one suggested moving planet that way, man think again ISP will not help here, just imagine what it means for a planet, just magma ball, not a planet) It may be more gently dissemble, which is more energy efficient and more control over stuff, less mess and less after work. But evaporating is the easy way to estimate max energy we need for the process. Disassemble Venus will take: mass\_kg\*E(escape velocity, 1kg)/Power(sun, 1sec)/Seconds\_in\_year > > (4.867\*10^24 \* 10360^2/2)/(3.828\*10^26)/(365\*24\*3600) == 0.022 years or 8 days > > > This is rough estimation, which isn't counting escape velocity changes because of planet mass loss, but it also not counts efficiency of process, which is less then 100% because loosing energy by heated plasma trough electromagnetic waves emission. But overall I'm ok with that number. ## Same for Jupiter > > (1.8986\*10^27 \* 59500^2/2)/(3.828\*10^26)/(24\*3600) = 101613 days or 278 years. > > > I'm practically ok with that number, but I think 2000 min of my time worth to improve efficiency of process at least for 1% be more efficient, even humanity may think one year or two about that situation, before to begin some movements in that direction. Sure, we have to recuperate our energy, probably we do not need that hydrogen cloud flying around, if we need hydrogen we may scoop it in any place in universe. So probably we will make 3 piles for hydrogen, one pile for He, and small moons with elements, one moon for each. As we already sorted the Venus, so I expect 0.2-0.5% by mass carbon stuff with 100GPa strength to operate, which will be useful to deal with decomposition of gas giants. ref [1](https://en.wikipedia.org/wiki/Abundances_of_the_elements_(data_page)), [2](http://periodictable.com/Properties/A/UniverseAbundance.html) I'll take optimistic number 0.2% - it means 1e22 kg CNT, not bad it's already 1/7 of moon mass, so we may already start to move earth, but thinking spares time in that planet moving business. So we will use that material to cook Jupiter first. 3 Pile H and 1 Pile He, each is 1/4 of Jupiter mass, each will have radius something like 44-50k km and escape velocity 38 km/s and having Jupiter in 4 such piles - when recuperating energy, will save us 40000 days. Not bad not bad. (you may wish to play with escape velocities [here](http://keisan.casio.com/exec/system/1360310353) I could be satisfied, not each day you may save 100+ years of work for entry civilization, sure they could figure that for them selfs, but, u know ... I'm not satisfied with that 60000 days of decomposition, not only because it's long in time, but because of slow start of such process, before we may start to recuperate reasonable amount of energy from placing mass in a pile, first pile will be ready in something like 10k days , and at that time we will recuperate much less then 40%, and we actually do not get something useful from that mass, it's still just big pile which we actually do not need. We need max 1% or less of that gas giant, so max number of days which looks good is 1000 days or less, for first giant, for CI tech, but bad part is most interesting stuff is in core, and to access core we have scoop out most of GG. ## Gas Giant or reason to move planets * Man said - before selling something unuseful, u have to buy something unuseful. And we already have that unuseful, deal of the life, 99% of Gas Giant we do not need, and we may exchange it for what we need in [star](http://periodictable.com/Properties/A/SolarAbundance.html) As a body orbiting around star, planet, or gas giant already have all energy we need for such exchange. But we as just CI civilization with a big hammer, we may need energy from the star as a catalyst for that process and compensate our losses etc. Efficiency is one limiting factor, so 90% efficiency means 10 times faster disassembly. *So exchange GG mass, for something useful from star is one of the reasons to move or change something in planet orbit.* ## Note about Venus scrap, snake elephant *probably most important part of that answer* I expect, and I have reasons for that(humanity lazy and smart is at least one of them), Venus scraping has been done more gently, and we have products as result, not a big cloud of materials. After successful scraping Venus we have 1e22kg CNT, and I have to explain what I consider as my knowledge about what that actually means, and probably that is the only reason, why I write that answer. You probably have seen that [Tesla snake](https://www.youtube.com/watch?v=uMM0lRfX6YI) funny elephant manipulator, and if you search youtube for more, you will find more, maybe not best search keyword but still, [elephant manipulator](https://www.youtube.com/results?search_query=elephant+manipulator) And as one interesting, and most importantly, simple design, I will point that video: [Robotic arm inspired by the Elephant trunk, time 4:08](https://youtu.be/Q1MBIaNuLa8?t=248) What is good about the design its simple, device made of same or similar parts - simple to produce, efficient to scale its production etc. There are other interesting use of properties of CNT [this](https://www.youtube.com/watch?v=Qzg2qA1ltK0), [this](https://www.youtube.com/watch?v=xMGXqT0LWUI) this here [Carbon Nanotube Muscle #2](https://www.youtube.com/watch?v=TD5LOaLjLlQ), the material itself is not important, important is the ability to make strings from it and their conductivity and strength. Both of that principles combined(and they are not all possibilities, we already know), allows us to make 100GPa strong, very flexible manipulators. And as CNT are very thin by their nature, such manipulators may be very thin too, and strong, and they may form more ticker manipulators. So imagine that tesla snake but made from at least 500 times stronger material(I bet that tesla snake is weaker then 200MPa, which is the strength of ordinary steel cable), and definitely more flexible. So imagine one unit same thickness as tesla snake but longer, 100-200 meters long, each equipment with some processor, some swarm algorithms, some sensors over surface: light pressure temperature etc - everything we may need for that unit is made from one material (maybe with some little additions of other materials, not as parts but as additive to change some properties of CNT's in desired way - but mostly 99.9% it's just carbon). And it is assembled from thin actuators. So that one unit, which we may control by programs, with strength like space lift cable, may change shape, bend as we need, react as we need, be thick as we need (from microns to how much you have), works from 0K to up 2300K temperature, is very precise in form making-changing, is dynamic in form-shape, stiffness. If you understand that moment, you will never wonder about howto make big constructions in space, huge ships, big thermonuclear reactors, your cubic worlds, many things considered like handwavium stuff, may be done from or with that. If you go deeper you will not wounder about speed, anything under 1c is not a problem for you. It's not nanobots trough, it's better, stronger, it will pass any reality-check, it's real. There are downsides too, you will begin to wonder how things may break at all, why they do not change shape, why they just make just one thing all the time, why you cant just upgrade thing like phone today, oh wait why I have to buy new phone why not just take small piece from that big chunk which plays jet at the moment and convert it to phone, who needs space suites, why people think gauss gun of any kind is wunderwaffe, why someone have to resupply something, why someone can't gather another 10kkk people and fly to some star on vacation, or make honey moon in center of our galaxy and return back 100k years later, why all will live on planets instead of comfortable space habitats made from smart material, why someone thinks pressure 1000bar is too big, why slicing 100-1000km asteroid in dust is too hard. Planet stuff is most annoying from them all. True limitation will be energy, and law of physics, there will stay things you can't do, taking core just away from gas giant is *probably* one of them, also taking core from earth size planets one of them too(but you may take stuff from 2000-3000 km deep), moon size object core will be not a problem, moon can be mined just as it is. Slicing earth size planets is not a problem, by removing upper layers - layer by layer. ## Tool, Space swiss knife Main valuable resource, from decomposition of Venus, is 1e22kg of active meta-material, actually it is our tool, which have to help us exchange 99% of mass Jupiter to stuff from star to make even bigger tool. Tool consists of parts with different sizes and ticklishness, typical muscle let's say 1km long, square 10x10cm (I'm lazy mess with Pi, or any complex form), density 1 t/m3, strength 50 GPa, they may stick together with good seal and slide like linear motor, be reprogrammed to other form with accuracy 0.1mkm They may store energy 10MJ/kg at least, as mechanical energy like spring, and release it like capacitor(fast if needed, mechanically or by generating electricity), with approximately 0 storage discharge. They may store and convert electricity to kinetic energy and back. They may conduct electricity, they may regulate temperature like peltier modules probably close to [theoretical value](https://en.wikipedia.org/wiki/Heat_engine#Efficiency). I assume 100% efficiency, but even if it is 50% this is not a problem, but I expect it to be 90% and above, like high power [electric motors efficiency](http://www.engineeringtoolbox.com/electrical-motor-efficiency-d_655.html). 1e22kg it will be 1e19 of TMU (typical muscle unit), it is also 1e19 km long cable 10x10cm, which is 66,666,666,666.7 a.u. long cable, or 11.5x11.5km cable with 5 a.u. length. and all that mass orbiting on orbit of Venus with rest of Venus scrap, which is 99.8% of previous Venus by mass, which may be used as reactive mass for that tool, with wide range of ISP values actually, this linear motor sliding of TMU is quite handy. Current form is probably ring-toroid(venus like orbit or close to that), to keep tool less dense, and to avoid need to wait 8days of star work to unfold it(with all that 99.8 not so much useful stuff) to something useful. But tool alone may be moon size(which is 7 times more we have atm) at least, and unfold pretty fast, something up to mars sizes is ok for dense and compact storage(everything with less then 3.3km/s escape velocity, which is around limit of static energy storage capability, is ok for tool, but it could be much bigger then that with other types of folding it). We could exchange venus scrap first, but we do not have to, and we rather will have metal elements(everything above He), then loose them, because they may be used for transmutations by neutron capture(forgot process name, something like [Nuclear transmutation](https://en.wikipedia.org/wiki/Nuclear_transmutation)), it's specially useful if you have star as neutron source and ability to efficiently expose material to it, some isotopes of ordinary materials like Fe as example, are more valuable then other isotopes of same material, also it can be used as passive protection layer preventing degrade our Carbon based material, specially if we wish to dip some parts of our tool in to star inner, and bunch of other reasons). With 10MJ/kg storage capacity we may store 260 sec of star energy, not bad, but it may store way much more than that (as kinetic energy). Because tool consists of elements, which may slide against each other(let say 1m/s, not top speed but reasonable speed of sliding), flex on command, we may separate them inside in 2 rings, two sets of MTU. Energy stored in [Venus](http://nssdc.gsfc.nasa.gov/planetary/factsheet/venusfact.html) motion is 90 days of Sun work. Gravitational potential is: $U = -G \frac{m\_1 M\_2}{r}\ + K$ Difference of potential energy between Venus orbit and Earth orbit, will be: > > 1.98855\*10^30 \* 6.68408\*10^-11 / (108\*10^9) - 1.98855\*10^30 \* 6.68408\*10^-11 / (150\*10^9) = 344597744.4 J/kg > > > To move Venus to a different orbit, Sun has to work with 100% efficiency : * to Earth orbit, 1 a.u. - 51 days * to Jupiter orbit, 5 a.u. - 155 days * to fly away - 181 days To move Jupiter: * to Saturn, 10 a.u. - 4693 days with proper tool we could form binary system of them, and refine at least one body pretty fast, saving some years. Or refine them both in 3th body. But we have to have tool for moving GG first, but with such tool we could refine them in place. * fly away, 9779 days * to Venus orbit, get energy 60847 days of sun work, although we can't do it now, but that's interesting number, ~150y of star energy, possible number for moving hot GG to more distant orbits. [](https://i.stack.imgur.com/rvery.png) Just as notes: * We can change inclination, by splitting ring again in orbit plane, if we have to [Venus](http://nssdc.gsfc.nasa.gov/planetary/factsheet/venusfact.html) inclination is 3.39 deg, [Jupiter](http://nssdc.gsfc.nasa.gov/planetary/factsheet/jupiterfact.html) 1.3 deg, [Saturn](http://nssdc.gsfc.nasa.gov/planetary/factsheet/saturnfact.html) 2.49 deg and because 99.8 percent of Venus is just scrap, which we use as we need without much care about, we may make small moon perpendicular to ecliptic - I notice that just for ease of understanding, we do not have to loose any reactive mass in that case, we need just energy, and compared to other task it's rather small. But yes, we have to respect momentum and impulse conservation. * Friction between rings or any other energy loss isn't big issue, surface area of tool is pretty big, and if it stacked such way as just disc, it may dissipate 100% of sun energy at temperature 900K, which is 627 °C. And this is without other 99.8 mass venus available to use as parts of heat dissipation system. Actual friction and energy loss is on level of good air bearing or better(which they actually may be, but this isn't only option). For those who isn't familiar with air bearings u may have to look at [this](https://www.youtube.com/watch?v=l2B12U6NtQw) and [this](https://www.youtube.com/watch?v=lOTWx69mghM) as examples * As we have 2 rings rotating in opposite directions, in earth orbit it will be 60km/s difference (30 in one direction, 30 in another direction), as we set TMU slide speed to 1m/s (to be suitable for different approaches and implementations) it means 60000 layers separation between two main rings, as TMU is 10x10cm it means that area is 6000m wide intermediate ring * I took air bearing principle because that way implementation does not depend on the internal structure of TMU and that way it is easier to refer to today's technologies, but this isn't only option. * layers could be thinner actually nothing stops us from using 1mm tick layers, or 0.1mm tick layers, this is more question how strong we wish them to be, and how much sliding force we wish to have. * There is no centrifugal stress from rotating rings, they orbiting, but just close together, so zero force for them. There is no difference (practically) in which rotation direction to orbit, just in case. * only part which is not orbiting properly are separation layers, but forces are small, 6km wide separation layer (if assume it not rotates at all) on venus orbit will press on inner ring with pressure 6800 Pa, on earth orbit 3500 Pa, so actual pressure between layers will be less then 1Pa typically. * with 1,5,10,20 a.u. ring radius, we still may make enormous amount of layers, if with TMU(10x10cm 1km long) we have 66'666'666'666 a.u. cable to play with. As TMU consists from less smaller strands, we may split it in smaller units or build bigger units from them - so it's just typical unit we operate at the moment. * gravitational influence from other bodies, may be compensated by playing with layers, and counterweight strands. Also this is one of the ways to tune star system, and affect orbits of all bodies in system at once. *it may be a way to convert potentially unstable (for billion years) system to stable one. Way to move planets actually. But long way, not efficient.* * I do not talk about micrometeorites, asteroids etc - you may guess, not a problem (just collect them , omnomnom) * We may have an elliptic ring, changing orbital velocity along orbit is not a problem with sliding strands. We may convert circular ring to elliptic, at least several ways to do so. One by splitting rings. Rings arranged something like that, black are rings: [](https://i.stack.imgur.com/1NkMo.png) ## GG scrap, lift setup * To scrape Jupiter for 10years or less - we have to have mass transfer something around 60'185'185'185'185'185'185 kg/sec or 60kkkkk ton/sec * Elliptical orbit of ring on Jupiter to Venus orbit, have period something around 5 years, so first year or two we will be kinda limited to Sun power, which allows us to lift 2.16e+17 kg/sec or 216kkkk ton/sec * to scrap Jupiter in 10 years, we have to lift 6e+19 kg/sec * Orbit velocity at Jupiter orbit is 13 km/s, orbit period is 11.9y * would be GG on earth orbit, it would make operation easier * Sphere from TMU, one layer tick (10cm), approximately 318km radius under 1 bar pressure Hydrogen+, will be 12'170'840'439'815'458 kg of Hydrogen mix, or 1.2e16 kg. TMU mass will be 1% of Hydrogen mass. I will refer that sphere as Spoon Unit (SU) * 10y scrape plan means approximately 500 Spoon Units per second to lift * some gravitational effects are omitted because they can be compensated, and it's not only one way to do the job. * originally I wished another approach to describe, but this looks simple to explain. * challenge is big, and the tool is too small, so 10y plan have to be smarter then I describe. Plan is simple, we will make a balloon from Jupiter. 1e22 kg TMU is enough to cover entry Jupiter with 23.5 km tick layer, at his 1bar level, it will squeeze Jupiter up to 2347 bar pressure inside that balloon, just by gravity force. With using 99.8 percent of Venus aka dead scrap this pressure could be higher up to 500 times and probably more. We do not apply force by tool, it's just gravity of Jupiter, and our limit is structural strength of TMU, which is around 50GPa or 500'000 bar. I'm ok with 1bar pressure near TMU shell, so we need 10m tick layer or 100 layers of TMU, this will be a not perfect sphere, but we ok with that because of the flexibility of our shell and mobility of our TMU units so we may dynamically compensate what we have to compensate. For that shell, we have to allocate approximately 1/2300 of our tool, by mass. The shell may be formed in different ways, hm that's stupid but like [that](https://youtu.be/a-4vRhg0Rt4?t=96), I wished guys did that better than that, but... it illustrates. After we formed shell over-around Jupiter (it will not fall it's just replacement layer for what was there before(part of atmosphere)) we have 1 bar pressure inside one side shell, and 10m over on other side of shell, we have vacuum. We do not apply force, we just chill on hydrogen couch. On vacuum side, over that side we may wish to form 2 rings, same 3 layer structure, plane of this set have to be same as plane of main ring, and they will stiffer our balloon, pre-stretch let say equator region, to allow us to lift SU units to vacuum side (E=m*g*h style). and to accelerate SU units to orbital velocity, same principle as [Launch loop](https://en.wikipedia.org/wiki/Launch_loop) but instead single rotor there is 2 rings and intermediate layer. 1 SU with Hydrogen, near hull, will weight 1.2e16\*23.12=2.8e17 N, and to be able to withstand that force cable should be approximately square 2.5x2.5 km (everything could be done inside the hull itself, by forming same structures or proper equivalent of them, it can be done in different ways) We open hole in the shell, pressure blows our SU up, like glass blowing process, the bubble moves away and we begin blow next - continuous process. 3layer ring system which accelerates bubbles one ring in one direction, another in opposite direction. layers have to be pretty big, to be strong enough to to be able accelerate pretty massive SU, but we may do that with smaller SU's if we have to. from 1% of 1e22kg active mass with resulting volume of 1e17m3 we may make 15x15km ring with radius 75000km, we also may wish to add all(or significant part of it) venus scrap to act like rotor in launch loop, we need just inertia mass to distribute stress over ring. Accelerating SU at 1m/s2 is pretty reasonable value. So at max productivity there will be 500\*59000 SU units, the mass of active material used for that will be 35% of our tool. * 35% of TMU's for accelerate process * 5% for Acceleration rings and reinforcement rings * 50% of scrap for rotors for acceleration rings, and for rotors of reinforcement of shell. * 0.05% for shell around Jupiter *I reconsidered approach slightly, will be below, but I leave this part as it is, as possible use case* After acceleration to orbiting velocity's, we attach SU to ring on close to Jupiter orbit. There will be different proportion in both directions, because of 13km/s Jupiter orbital speed, and we may wish to keep the momentum of the ring. ## Refine Jupiter mix, problem Intensive disassembly of Jupiter is actually challenge, there is set of problems: tool is too small, some processes still needs years to accomplish like cooling SU's, separate mix in to components, transfer closer to sun. Although some problems may be solved, I wish more general overview of the process, without going deep details of possible solutions. To imagine what intensity of process is that 10y plan, we have numbers to tell us that. To make something near 10y plan, we really have to blast Jupiter, just nonstop blasting. Sending 500SU/sec, with content mass 1.2e16kg each, means each 1m2 of 75000km radius sphere, should have flow with velocity 970 m/s at 1 bar pressure. SUvolume\*500/Jupiter\_surface(75000km radius) = (320000^3\*4/3\*3.14\*500 / (75000000^2\*4\*3.14)). As we have regions where SU are forming it means compression(just adding more mass over shell top in that region) will make pressure and density more and thus flow speed less. Probably we have to use entry equator region to fill SU, and this region will be our acceleration ring, which we will divide to SU's later. So it kinda shell flows to equator and accelerates perpendicular to flow, so on equator we have most energy it needs - everything is preloaded with venus scrap. Pretty much is happening there in that process, but I ran out of space to describe. * we do not have to stress entry jupiter, it's enough just to bend equatorial part to desired pressure (any pressing we do by just placing more weight in that place. That ring starts somewhere 300km deep under surface, Scale height 27 km, pressure 70000bar) [](https://i.stack.imgur.com/frb0F.png) Growing Active Material is critical for the whole process. Each SU content contains 0.3% of CH4 by volume or 2.4% by mass, and SU itself weights 1% of that content. So when we manage to separate CH4 from that mix, we may make 2.4 new SU for each SU we send down to venus orbit. Extraction should be done directly from Atmosphere of Jupiter by shell AM. We have to extract building material until we close cycle, and SU will begin to return back for reuse. After that it can be done anywhere underway. That way we may have a continuous growing flow of SU up our max needs. 1st priority to grow tool first. Separating CH4 may be done in many ways but over all just usual gas separation, but on large scale with AM. Good about that, more we get, faster we get next portions and we have more than enough AM for such task. ## Exchange I'll not describe mass exchange in details because the topic is bigger then I have already written. * local magnetic fields in sun spots are [0.3Tesla](http://nssdc.gsfc.nasa.gov/planetary/factsheet/sunfact.html)(probably not extreme case but above average field which is 1/10000 T, twice of earths), we do 2T with current approaches, and we definitely can do more with stronger materials. * there are some suggestion for probes and support-stabilizing strucures for thermonuclear reactors which are inside that reactor surrounding by plasma, they are protected by their own magnetic field. Same way we may protect parts of our tool inside sun. * as we transport mass from Jupiter, we have disproportion of momentum in tool(because of jupiter's momentum), mass exchange with sun is way to compensate and move that proportion to desired equilibrium. * Sun scooping may be done with same 3layer ring system * Because surface area grows like x^2 and volume like x^3, bigger part is, longer it may stay in hot area. Despite passive materials, with moving strands inside part, we may do much better and faster heat distribution in part, also we have plenty of Jupiter scrap to use too, as protection gaseous layers, if we have to. * Probably we cant dip to deep. Density of suns photosphere is 0.0002kg/m3 and that's not bad actually, pressure is also not very high [Sun](http://nssdc.gsfc.nasa.gov/planetary/factsheet/sunfact.html). * Energy flow in photosphere is 68MJ/sec/m2, but with AM we may have entry ring inside photosphere, and separate heavy isotopes just directly there. (sure with some cooling setup outside sun, connected to that ring) ## Conclusion I hope, at least partially, I have answered OP's Q, even if I skipped some details, because of A size limitations. The whole concept heavily uses Centrifugal force direct or indirect(like orbiting bodies them selfs) aka inertia - so you have to understand and be familiar with [Orbital ring](https://en.wikipedia.org/wiki/Orbital_ring), [Launch loop](https://en.wikipedia.org/wiki/Launch_loop), [Space fountain](https://en.wikipedia.org/wiki/Space_fountain), [Orbit](https://en.wikipedia.org/wiki/Orbit) Playing KSP help to understand some basic principles of orbital mechanics, fly safe. There are other games with some realistic orbital mech, and that's good. C. Clarke is genius, Gerard K. O'Neill is great. Special tanks for Google and Internet, without your help guys, writing would be impossible. [xkcd](https://xkcd.com/536/) I Do Not Laugh Anymore, Ever, Thank You Very Much C.C. [Answer] ## Stellar Laser Propulsion The problem with strapping any sort of engine, such as a chemical rocket or an ion engine, to the planet is coming up with enough energy to actually *move* a planet. Luckily, planets tend to be found close to sufficiently large sources of energy to move them: stars. The trick is to figure out how to use the energy of a star to move a planet. To do this, we'll take inspiration from a fairly novel form of propulsion engineers have been playing with on Earth: [laser propulsion](https://en.wikipedia.org/wiki/Laser_propulsion), which typically works by focusing high-powered lasers on a reaction mass. The lasers rapidly heat the reaction mass, which vaporizes and produces thrust. In this sort of system, there is no energy stored on board the vehicle, either in the form of chemical potential energy, like with chemical rockets, or in nuclear energy, which is generally used to provide the electric power that ion drives use. What we'll do is construct a Dyson web comprised of satellites with solar panels and lasers attached to them. These satellites will convert all of all of the electromagnetic radiation given off by our star into radiation we can direct towards the planet. All of these lasers will be focused using a lens or mirror array onto a single point on our planet, at which point the planet's surface will begin to vaporize from the heat, emitting a jet of high energy particles which will act as a thruster, pushing the planet towards wherever you want to go. Energy-wise, it takes the sun about a hundred days to produce an amount of energy equivalent to the kinetic energy of the Earth, so it will take a few years to accelerate the Earth to escape velocity. At that point, it will caroom across the galaxy towards its destination, where you'll have another satellite array waiting to slow it down at the end of its journey, assuming you've aimed everything right. The planet may require some cooling once it reaches its destination. **How much mass will we lose?** The Earth travels at around 30 km/s, and its escape velocity from the sun is 42 km/s at a distance of 1 AU. This gives us a $\Delta v$ of about 12 km/s. Ablative laser propulsion has a specific impulse of about 1000s, which we can plug into our equation for our fuel fraction: $e^{\Delta v/-v\_e}=m\_f/m\_0$ to get a final mass fraction of about 30%, meaning that we will ablate away 70% of our target planet's mass getting it up to speed. That being said, the more we can focus the light of the sun onto a small area, the higher the effective exhaust temperature will be, resulting in a higher specific impulse for our thruster and a smaller mass fraction. If we can get the specific impulse up to 10000s, our final mass fraction would be 89%, meaning we'd only need to ablate away 11% of the planet's mass to get it out of the solar system. The value I used in my initial calculation is based on the best that human society has achieved until now using ground-based laser systems, so it's entirely possible that our Type II civilization could achieve $I\_{sp}$ values an order of magnitude higher. [Answer] Build an [Alcubierre drive-system](https://en.wikipedia.org/wiki/Alcubierre_drive) around the planet, assuming you can build them that big, and then transport the planet to your preferred destination. Essentially an Alcubierre drive moves a volume of space, and if that volume of space just happens to contain a planet so much the better. There will be a few technical problems as the planet will retain its state of motion inside that volume within the Alcubierre vessel, but a civilisation this advanced should be able to cope. Recent thinking on Alcubierre drives suggests they work best below lightspeed, so the planet most likely will relocated at sublight velocity. Gravity tractors using asteroids have been proposed to move the orbits of planets in the solar system. This technique might work for the interstellar transfer of planets, but it would be hellishly slow. But there is better alternative for a gravity tractor. Namely, neutron stars. Observations have been made of runaway neutron stars. Let's assume our advanced civilisation can construct sufficiently large wormholes, say, with a diameter around 100 kilometres. Using a series of wormholes it might be possible to shepherd the neutron star close enough to the planet to act as a gravity tractor. This would involve multiple close passes of the neutron star to the planet. The neutron star would have to emerge from the mouth of the wormhole near the planet and move away from it in the direction of its destination. The planet will accelerate due to the neutron star's gravitation. On approach to its destination, the neutron star will go through repeated manoeuvres to decelerate the planet. This means at the halfway point in its galactic journey. This arrangement will require a reasonable number of wormhole mouth pairs attached to space vehicles to get into the correct positions to enable the right passes of the neutron star relative to the planet. The motion of the neutron star will need to be reoriented so it is moving in the vector towards its destination. Since neutron stars are extremely robust objects extreme measures can be taken to do this. Dropping extremely large amounts of hydrogen leads to thermonuclear explosions on the surfaces of neutron stars and this might be used to steer the runaway neutron star to line it up correctly. My third method is purely hypothetical. Use a Herman Bondi-style of diametric drive to move the planet. This will involve placing a large positive mass and a large negative mass on either side of the planet. The masses in question will be relatively large compared to the planet's mass. I will assume that the two masses will be drawn out of the quantum vacuum and since they involve equal masses of positive and negative mass-energy the nett mass-energy budget will be zero. In this configuration, both masses will accelerate away in the direction of the positive mass. The theory behind this can be found at <https://en.wikipedia.org/wiki/Negative_mass> and that of the diametric drive at <https://en.wikipedia.org/wiki/Breakthrough_Propulsion_Physics_Program#Diametrical> To slow down the planet and its diametric drive the configuration of the two masses is reversed and the system will undergo deceleration. It is nice to notice that the two masses don't need to be equal for this drive to work. This would be the fastest method of the three I have suggested for transporting planets across the galaxy. A diametric drive planet transport system could reach near-lightspeed. [Answer] For something like this, it'd likely be more feasible to manipulate spacetime to get your planet where you want it to go, rather than moving the planet itself. If the planet in question has inhabitants, this becomes even more of an attractive solution, as you'd have to protect life on the planet while it's being moved. Folding space effectively eliminates the hazard of a long voyage through the deep black. [Answer] Use dynamic compression members - basically a stream of high velocity pellets transferring momentum (preferrably from the Sun). Description and calculation is in the article *Paul Birch: How to move a Planet. In: J. Brit. interplan. Soc., 46, 314 (1993)*, available online at <http://www.orionsarm.com/fm_store/MoveAPlanet.pdf> Summary: by transferring momentum from the rotation of the Sun, it is possible to move e.g. Venus to Mars orbit in decades, given enough pellets, quite within established science (if not technology). Of course, moving a planet somewhere else in the Galaxy is considerably more difficult and time and energy demanding. [Answer] If you're not concerned with killing everything on the planet, the idea that pops into my head is to throw things at it. Instead of turning the rockets of a spaceship on at the apoapsis and periapsis, find a rock that's big enough to have an effect and make it collide with the planet at the apoapsis/periapsis. The issue with this idea is that anything big enough to matter would also break the planet so badly I don't think it would count. Second idea: aim for a near miss. Throw the biggest thing you can attach rockets to at the planet, but miss by a very small amount. Essentially the same as a gravity assist on a vastly different scale. This could work if applied strategically (mostly at the apoapsis and periapsis) over many of the planet's years. Your civilization could place a number of super heavy spaceships into the same orbit as the planet to give a gravity assist regularly. With this setup, acceleration caused by rockets could be very gradual because the ships have most of the year to adjust their orbits before they are near the planet again. Over a long period of time, you shape the orbit of the planet into a very irregular ellipse pointed so that when it finally reaches the tipping point and becomes a parabola, it will be headed toward your intended destination. [Answer] ## Hyper-density Black holes Considering the fact that the weight of Earth is over a billion billion tons. Yes, I said **Billion** billion. There is no realistic way that it can be pulled. Let's look at gravity then. Using a super collider-like device, small hyper-dense black holes can be used to use gravity to pull the planet. **Advantages** * It is simple and easy to do. * It can be done with modern technology (theoretically) **Disadvantages** * The black holes may attract unwanted celesial bodies. * It will be extremely difficult (if not impossible) to do this with planets with moons or rings. * Black holes can be very unstable * It will take a long, long time. [Answer] Build Shkadov Thrusters to move the planet. That’s right, Stellar Engines work on planets too. You build mirrors in space that are held within the gravity well of the planet. The mirrors reflect the energy escaping from the planet. My calculations based on lower estimates of reflected solar energy comes up with an acceleration of 1.748 \* 10 ^-8 m/s or .55 m/year. This is a slow acceleration, but it is constant. You could also increase the acceleration rate with the addition of ground based radars. Also, heat radiating away from the planet adds to the acceleration, but I could find no accurate measurements for earth’s radiant heat. **Bonus 1:** Usable with current tech. **Bonus 2:** You can still use nuclear weapons if you want. Calculations: 174 pettawatts solar energy in \* 30% reflected from the atmosphere = 52.2 pettawatts. 52.2 pettawatts = 5.22 \* 10^16 watts. Mas of earth = 5.972 \* 10^24 kg. Watts/kg = m/s (then we double that since mirrors provide double the thrust [don’t ask me why the reference video said so]) 1.748 \* 10 ^-8 m/s [Answer] You don't. At most you scoop off the atmosphere and biosphere, soil, some oceans... One rocky core is much like another but it contains most of the mass. If sending the planet interstellar expect million year transit times and a very cold planet. (this is if you want more than a ball of molten rock.) [Answer] ## Electrostatics! Since you are not in a hurry, you can increase, or decrease the attractive force of the star on the planet. Changing gravity is though, but creating ions that generate a very similar force is easy. I will now assume you want to get your planet closer to the star, it is easy to do the opposite and have the opposite effect. --- The plan is to turn the star into a big positive electric charge dump and the planet a negative one. Why not the opposite? [Solar winds](https://en.wikipedia.org/wiki/Solar_wind "solar")! Stars eject part of their mass at space all the time, so you don't want to trow anything light at them. So, you build a satellite that launches a stream of very heavy ionized nucleus at the star. That same solar wind will try to get some undesirable electron into your stream and foil your world moving plans. To avoid that we will probably need a chain of satellites with which to shield the stream by clever use of magnetic fields (made easier because you know from which direction the particle wind comes). Still the same annoying solar wind will cause us more trouble. By moving particles from the star to the planet we can get a dreaded electric current between them even if the whole stream is perfectly protected. The solution? Making our ion stream **massive**. The stream should move more change than the solar wind can counter. The increase in total change inside the star might influence the amount of wind expelled, but it will go in all directions and the extra amount that arrives on the planet should be small. **In short**: place an array of satellites between planet and star guiding and protecting a massive stream of super-heavy futuristic nucleus into the star. --- *After thought*: Differently from the atmospheric engine in other answer, this stream is not massive enough to move the planet by action and reaction in any appreciable manner. If the solar wind is really powerful, then the charge buildup will be canceled and the stream will actually pull the planet away from the star very slowly. [Answer] Antimatter-based propulsion. When antimatter comes in contact with matter, both annihilate, transforming all of their mass into ridiculous amounts of energy (mostly gamma radiation). The testing of a similar engine is described by Stanisław Lem. Build an antimatter engine outside of the atmosphere, anchored firmly to many spots on the planet so that it doesn't dislocate continents or anything like that. It will be shielded from the side of the planet. It will propel the planet by pushing the shield, and by Newton's third law, like a next gen jet. The energy absorbed by the shield can be then used to heat up the planet, to compensate for moving away from the planet's sun. Pros: 1. Simple linear propulsion. 2. No need for external objects. Flaws: 1. Antimatter has to be somehow produced and stored. 2. Uses up matter and antimatter. 3. Shoots a beam of death into space. [Answer] The basic principle of moving an object by thrust is the same no matter the size of the object. Just the amount of force you need goes up. With enough engine power, you could potentially move a planet. "The Wandering Earth" is a short story by Liu Cixin that has this exact topic and reads at the believable level, i.e. no fancy super-tech, wormholes, unobtanium. In the story, gigantic rocket motors are installed on the planets surface, and fed with entire mountains (so it appears they are some kind of fusion drives or matter-energy converters). It takes decades for Earth to leave orbit, and a century or two to exit the solar system. There is actually a "braking period" where the engines first stop the rotation of Earth, so that they can then provide forward thrust. [Answer] lets keep this simple, a rogue planet, flung from its own star in a supernova, passes through your planetary system. the gravity of the planet is strong enough and it passes in just the right place to alter the course of your planet outside the gravitational influence of its own star. what now? well... it simply floats away i guess... goodbye planet.. we'll miss you :(... now i see you mean to move two planets, one basic idea is an eruption of the star, in the hope that both planets are far enough away that they dont disintegrate. another idea is a phenomenon called a "white hole" on a small scale, its never been witnessed but is possible. it occurs when so much energy is forced upon some amount of matter that the matter performs a quantum warp. we know this is possible becaus in computers we have made the barriers between pathways for electrons so small that the electrons have been witnessed building energy and warping to the other side of the so called barriers. this isnt exactly a white hole but it proves the idea of a quantum warp. some scientists believe that black wholes do generate enough energy that when something falls into one it builds enough force to warp somewhere else, you could do a few things with this, you could have a white hole appear naturally and blast the planets away. or if your society is technilogically advanced enough you could compile nuclear energy from fusion in such a high amount and blast your planet into a warp tunnel. if your a halo fan you could think of it as sending your planet through slipspace. [Answer] **If matter can attract, anti-matter can repel!** Have the engineers build a anti-matter dispensing engine in the direction opposite to the path the planet needs to take. Pardon my pseudo-science, but as we all know (or all will know in the future) the power by which anti-matter repels is exponentially higher than that of gravity's attractive force. This means that the anti-matter generator would have to produce a fraction of what a matter generator would have to produce to pull a planet. ]

[Question] [ A colony ship headed for its new home countless light-years from Earth suffers an unfortunate malfunction on the final part of its descent phase and crashes onto the planet. Thankfully, the ship crashes near its intended landing zone which is ideal in terms of fresh water/arable land. The ship impacts, knocking out almost all of the most advanced equipment for good, reducing the colonists to a close to modern (2019) level of technology, but with very limited initial availability. Very few of the population actually died as a result of the crash, but are now scattered across the surrounding countryside along the flight path (approx 100 miles) due to being evacuated via escape pod just in time, with the crew being the worst off, having sacrificed many of their lives to save the ship. As the colonists emerge, they discover that their intel was completely accurate: Prior scans before the journey began indicated the planet is for all intents and purposes considered to be an ideal world, just like Earth, but with different flora/fauna, etc. However, the scans missed a minor detail. Everything is just a little *hot*. ***Spicy hot.*** All types of plants and creatures seem to contain some heat, with the lowest being in the hundreds of thousands of Scoville units, with the most potent sources in the tens of millions or more (Feel free to adjust this range if necessary). A certain concentration even permeates the very air they breathe. The colonists are simply a random sampling of a normal population. This isn't the first colonization mankind has embarked on, and anyone can sign up at this point. Besides, this world was *"supposed to be a cakewalk"* provided the ship had landed intact. Unfortunately for them, outside help is likely to be at best, ***decades*** away if it comes at all. So the question is, can the colony, ***take the heat***? And what would their society/culture look like when the rest of humanity comes to check up on them? [Answer] **The colonists will rapidly be desensitized to capsaicin.** This assumes that the "spicy hot" on this world is capsaicin (the active molecule in hot peppers) or something that works similarly. There are other spices perceived by us as "hot" including those in horseradish, black pepper etc. Each has a different mechanism. As regards capsaicin: this molecule initially stimulates and then exhausts pain nerves. [Capsaicin: Physicochemical properties, cutaneous reactions and potential applications in painful and inflammatory conditions](https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6639979/) > > Capsaicin and its related vanilloids have a complex action on primary > sensory neurons with major role in physiology of pain by detection of > high threshold to physical and noxious chemical stimuli, as the first > step in producing the pain session (1). Initially, capsaicin induces > their activation, characterized by a local burning and stinging > sensation, possibly associated with hyperalgesia and allodynia after > exposure to heat and mechanical stimuli... In case of subsequent or > prolonged applications of capsaicin, initial excitation is followed by > loss of responsiveness, known as desensitization of nociceptive > neurons, which stands at the base of analgesic/anti-nociceptive effect > of topical application of capsaicin. Low-concentration topical creams, > gels, lotions... with capsaicin were developed to ‘defunctionalize’ > cutaneous nociceptors and treat painful conditions. Moreover, > capsaicin further depletes the neuropeptides from the sensory nerve > endings and reduces the initial inflammatory response. Capsaicin can > also induce a progressive neurotoxic degeneration of cutaneous nerves > when used in high concentrations or for a long period of time... > > > Given its analgesic and anti-nociceptive effect, capsaicin has been > used in the management of neuropathic discomfort, post-herpetic > neuralgia, neuropathy of patients with diabetes and/or HIV,... > > > Like a person using capsaicin lotion to treat pain, the colonists will initially be uncomfortable (and cough) but then the responsible nerves will rapidly be exhausted and desensitized and the colonists will no longer be uncomfortable. They might actually be relatively numb. That "neurotoxic degeneration of cutaneous nerves" sounds ominous - it is not good to be numb. That will have to do with the concentrations involved. [Answer] Other answers have addressed the serious problems with living in pepper spray, so let's assume you've dealt with that and move on to the food issue: Chickens. Okay, presumably you've brought some sort of gene stock for farming because you're not an absolute idiot. Let's assume that enough of it survived to get started. I've never heard of any plants being negatively affected by capsaicin, so you're probably good there. But what if you want some meat in your diet? Livestock requires a lot of space even if you have the infrastructure for factory farming, which you don't. Which brings us to chickens. Capsaicin affects mammals, but not birds. (This is not a coincidence--chilies evolved capsaicin to discourage mammals that would chew up their seeds in preference for birds that would swallow them whole and poop them out far and wide.) So chickens, geese, turkeys, ostriches, and any other food birds you may have will be able to live outside with no significant difficulty, and will likely provide the great bulk of your colony's protein. And of course that also means plenty of eggs! Dairy supplies will be limited and valuable, as cows/goats/whatever have to be raised indoors in limited space. Red meat is a rare luxury, available mainly when an old or injured animal is put down. Although, oddly enough, it may skew towards veal--bull calves would be slaughtered immediately after birth to save resources, rather than raised to adult size first. In any case, if four-legged livestock are raised at all it will be strictly for milk, with meat being a happy byproduct. (Oh--in addition to repelling mammals, capsaicin also appears to have anti-fungal properties. So you may be out of luck if you brought a stock of morel and truffle spores.) [Answer] It sounds like the simplest solution will be to build greenhouses and tents to live in and grow Earth plants to eat. Air and water can be filtered to remove the toxins or at least bring them down to tolerable levels. Since the "heat" in the local plant life is not tolerable, but I am assuming the plants are otherwise edible or useful as raw materials, then plants can be processed by soaking or boiling them in alcohol or some other solvent which removes the noxious materials. This is done either outdoors, or in a separate facility where people in protective suits and masks can oversee the process. How the waste is disposed of can be dealt with in a multitude of ways, including making parabolic mirrors and heating the waste into an incandescent plasma, breaking everything down into its raw atoms (this is by far the most extreme method, but heating the material until the toxins have broken down and then disposing of the waste is likely to work with most biologicals). Humans will find the place unpleasant, and living in greenhouses likely to be rather restrictive and slowing a lot of their planned expansion through the world, but nothing really insurmountable. Long term, a great deal of effort is going to be made understanding the local ecology and determining how to breed plants for a much lower level of "heat". Of course if plants need to generate this much "heat", then you should really be asking pointed questions about the animal life as well.... [Answer] [Capsaicin](https://en.wikipedia.org/wiki/Capsaicin) is irritating: when coming in contact with eyes or mucous membranes of mammals, it produces pain and breathing difficulty, that's why it is used in pepper spray and by polices to disperse ill intentioned targets. Since you state > > A certain concentration even permeates the very air they breathe. > > > this means that they will constantly feel like being sprayed with pepper spray. While the content in the food can be somehow mitigated (alcohol is a good solvent, while casein present in milk and cheese completely inactivates it), they will be forced to wear gas masks to be able to perform any activity. As you might know, performing intense physical activity while wearing a gas mask is challenging, to put it mildly. Their only hope is to evolve by not being sensitive to capsaicin any more. But that would take generations before being effective. [Answer] I take it you want them to survive? The things that might kill them off early on are: (a) the level of capsaicin vapour in the air which might act sufficiently like a perma-pepper spray that they just can't see well enough to accomplish anything. Either they need masks (if you want to up their reliance on technology) or the airborne level needs to be low enough to just create mild but tolerable eye discomfort (if you want to make things marginally more bearable for them long-term); (b) available food / water being so spicy that people can't bear to eat / drink enough (or can't do so without vomiting it back up) and die of starvation or thirst. If they can cope sufficiently with the airborne capsaicin and keep down some food and water, they will probably be able to survive, though I would imagine life will be pretty unbearable until they develop a strong tolerance. The hottest sauce I've tried is Blair's 3a.m. reserve at around 2 million Scovilles. I tried just a drop on the tine of a fork, and it caused me a good 10 minutes of pain. I can't imagine being able to consume enough food / water to survive if it were all a similar heat to the Blair's, let alone the horror of getting that level of heat in my eyes (or on my genitals) from simple exposure to the air. [Answer] ### Staying indoors solves this problem. The colonists just have to survive long enough to prepare "indoors". Most of the raw environmental danger is immaterial. It is *exposure* to the environment that is a problem. The described environment is so harsh and so inescapably unpleasant that the colonists would likely prioritize separating themselves from that environment as thoroughly as possible. A large building or complex of buildings is unlikely to bother the colonists all that much. After all, they've spent a great deal of time living in the colony ship itself (back when it was intact). Instead of dealing with the capsaicin in the environment, the colonists would assemble relatively airtight structures as quickly as they possibly could. Specific mechanisms would depend on what they could build and maintain most reliably, but coming from an interplanetary colony ship suggests that they have options potentially up to self-sufficient, hermetically sealed structures constantly recycling air and chemical products. Trips outside would be limited to necessary excursions, and involve protective gear like goggles and face masks or even portable oxygen tanks (like a scuba diver). Resources that need to be cleaned of capsaicin (maybe they need to eat some of the local food to maintain the population, etc.) could be addressed with various chemical processes (another answer mentioned some solvents that might help). These techniques would be best handled by trained specialists, but even if specialists were not available the colony ship would almost certainly have extensive technical information in a library that would preclude the need to learn the techniques from scratch. The major question would be if the colonists are able to build these structures given the difficulty of the environment. The answer to that depends on how much capsaicin is in the air (especially), as the effect could range from mildly irritating to totally debilitating. That's under your control as you define the setting, and so you can choose whatever level of attrition might apply until the airtight structures are prepared. The society of the colonists may not be affected by the spicy environment much at all, aside from being organized to limit contact with the outdoors. If they could survive on the colony ship, they can probably survive on this planet, as long as there is a large enough living population to perform necessary colony tasks. [Answer] The other answers ignore a common method for people have used for transforming terrain to improve habitability: Fire. Firstly, on finding the air toxic, most of the settlers will return to their sealed escape pods. These escape pods were designed for space, and atmospheric re-entry, and hence they are tolerant to thermal heat. Escape pods also have radios, so that the different groups can coordinate. People will need only use their space suits to enter the forest, light a rip-roaring fire, then go back to their pods, and wait. The pods, as stated above, are resistant to thermal heat, so fire won't be an issue. With the first 100,000 square miles cleared, they can begin Earth based agriculture. This agriculture will compete with local flora to reduce the quantity of "spicy air" in the area, and hence allow people to emerge from the pods. And if burning 100,000 square miles of forest is not sufficient, people are destructive enough to destroy all the flora on the planet, and replace it with gentle Earth Flora. While this isn't the most pleasant answer, these are humans after all. When they need to decide between their own deaths and destroying the environment, they will destroy the environment. [Answer] Well, they have no choice, so they have to take the heat. The component that makes peppers hot is called capsaicin. Pure capsaicin has 16 million scoville, so that's the maximum any of the plants or creatures may have. So they could for example drink lots of alcohol with their food, because capsaicin is soluble in that. The better idea - since you don't know which plants or creatures are toxic for humans - is to grow their own seeds from earth. They may still be a bit spicy, but they may be mild enough to get used to them. On earth, there are many societies that like to eat spicy hot meals, that may be too hot for people who are not used to it. [Answer] They probably wouldn't have known what the plant life was like on the planet before colonizing it so they probably have the means to grow Earth food. Even if the green houses on the ship were destroyed, they can purify water by distilling it and use it to wash \ soak the local foodstuff to make it more mild. Another way to counteract the spiciness is to dilute with water (eat a lot of soups), or add sugar, acid (lemon, vinegar), or dairy. Finally, if they do have some starchy foods like rice, potatoes, bread, etc, they can eat it along with the local stuff to make it more palatable [Answer] I have a lame answer but here it goes: [Capsazepine](https://en.wikipedia.org/wiki/Capsazepine). Capsazepine stops the painful sensation of heat and pain caused by capsaicin (and some other irratents such as the venom of some taranchula species) by blocking the activation of the TRPV1 ion channels. It has also has been experimentally used to desensitize the receptors permanently, to provide relief from chronic pain in specific cases. Logistically this is a great solution since Capsazepine is created by the chemical modification of capsaicin! Capsaicin does not actually cause a chemical burn, or indeed any direct tissue damage at all. The inflammation resulting from exposure to capsaicin is believed to be the result of the body's reaction to nerve excitement.[(source)](https://en.wikipedia.org/wiki/Capsaicin#cite_note-37) This would cause the body to inflame tissues as if it has undergone a burn or abrasion and the resulting inflammation would cause tissue damage in cases of extreme exposure. Side note: The TRPV1 ion channels are thought to be responsible for our range of temperature sensation. [Answer] An alien biogenesis and billions of years of random evolution would result in a completely different biochemistry. Whatever organisms lived there might well be based on carbon and water but probably not DNA as we know it. The amino acids used (if they were used at all) might be different with a different handedness and D-amino acids are toxic for most life on Earth which use L-amino acids. Basically life there would be at very best inedible and irritant and more likely toxic every step of the way. It would be like living in an organic chemistry lab where some mad scientist had cooked up thousands of different chemicals at random and was asking people to breathe them and eat them. So you scenario is in some ways likely but would be just the tip of the iceberg. It wouldn't end well, everyone would have to live in domes isolated from the environment to stay alive. ]

[Question] [ Let's not debate whether is there any friction while traveling inside vacuum space and assume all ships can brave a perfect storm brewing inside the giant molecular cloud. OK let's get down to business and tell me why my generation ship turns into a tuna? I remembered asking for a tetrahedron to save trillions of dollars so why should I pay that much to cross the galaxy? I see it also comes with sail and antimatter reactors. (No FTL upgrade option) [Answer] One reason that might play a larger part than you'd think is actually aesthetics. Sure, a big ugly ball of components is the cheapest option now, but will it net you any sponsors for your next mission? Will it inspire the next generation of potential astronauts? Will people back home look at your ship and think 'Yes, that's a ship on which I want to set out to the stars!'? If your ship is nothing but a mess of cold welded metal and ugly thruster ports then nobody will be inspired by it, like it, or want to sail (if sail is the right term for you) on it. If all you're doing is accelerating in a straight line to get from star to star and have the structural engineering wherewithal to avoid overloading the structure of your ship (which I really hope you do) then you can use any shape you like. If you make the substructure of your ship as ugly as you like and then slap an aesthetically pleasing superstructure on it (potentially with some nice holo-screens for in-orbit advertising revenue) then you can get more sponsors, recoup the costs of the nice design, and also net more recruits for your interstellar mission in the process. So oddly one suitable answer to your question is: **because it looks good**. [Answer] Space isn't a pure vacuum. There's still bits of rock and other debris floating around. Do you really want masses impacting your ship at fractions of light speed? Streamlined designs would have anything hitting you from the front sliding off at at angle, instead of transferring all the momentum to one point ***on an airtight vessel in a vacuum***. The ones hitting the sides must be endured, but they won't have nearly the relative momentum as a rock hitting the front while the ship is at full speed. Basically, the same reasons that ships are streamlined. [Answer] # Radiation Hazards, or why I learned to stop worrying and build my ships like skyscrapers. One reason among many is to shield the crew from Radiation. Not incident interstellar radiation, though - radiation from your own ship. Since solar isn't really an option in the dark interstellar void, chances are you're using some variant of nuclear power, fusion or otherwise. Sterilizing your crew and giving them cancer is generally frowned upon, and as such we need to design around it. The most obvious solution is to just put big monolithic blocks of lead between the reactor and the crew, but lead isn't known for being lightweight, and space travel is about getting the most use out of the least mass. Huge radiation shields are technically an option, but not a good one. There's hope, though. Radiation (Both particle and EM) falls off by the **inverse square** of distance. If I'm twice as far from the source, I get only one fourth the dose. Four times as far, and I get only *one sixteenth* the dose. It logically follows that I want to put my crew as far away from the reactor as possible. The easiest way to do this is to make the ship long and skinny, put the reactor on one end and the crew on the other. Between them and the reactor we pack our fuel/propellant tanks to help soak up some radiation, as well as any systems that won't be bothered by it. If the radiation is still too extreme you can put some shielding there, but you won't need anywhere near as much as you would if the crew were right next to the reactor. [Answer] A streamlined shape has more advantages than just reducing drag while travelling through some medium. The streamlined appearance is only on the outside. The outside also is the barrier between non-inhabitable space and the cosy inside. It is safe to assume that the material of the hull is fairly expensive, so you want to minimize cost for hull material. That means you want a shape that provides maximum volume per surface area. Geometry tells us that the perfect shape for this would be a sphere. So, why do you end up with a tuna, or a zeppelin, or something similar? Space is mostly fairly empty, but also really, really huge. As a result, you need to go very, very, VERY fast to get from somewhere interesting to somewhere more interesting. So you are travelling at mind-boggling velocities. Now imagine an obstacle. For example a pebble. Just sitting there in space (which it won't do, it will be moving, but that is not that important). Imagine hitting a pebble with a delta-V of something like 2000 times the speed of a sniper rifle's bullet. This thing will scratch the paintjob of your nice new ship somewhat badly. So you also want to minimize the cross section as seen from the front, because that is where the pebble will hit. A smaller cross section simply means less pebbles. Also, the steeper the slope of the front, the easier it is to deflect this pebble. Now you have a bullet nose. As for the tail section: This will most likely be anything that your engine requires, plus maybe some fairing, because even engineers tend to simple shapes when they can. Voilà, here is your beautiful interstellar spaceship. [Answer] ### Manufacturing and maintaining a ship *type* in a … larger space yard As long as your ships manufacturer is producing *types* or *models* of ships—instead of custom products—they will need to have a space yard fitting the ship. This factory would need to be either larger than the objects size, or it would have to adjust to a growing (for e.g. spherical) shape. Both difficult and expensive things to do. ``` /———⚇———⚇———\ Manufacturing area \———⚇———⚇———/ ↓ ❚ --------- /☳☳☳|☳☳☳|☳☳☳|☳☳☳|☳☳☳|☳☳☳|-/// ↑ ‹[ ☰☰☰|☰☰☰|☰☰☰|☰☰☰|☰☰☰|☰☰☰|-=== Ship \☶☶☶|☶☶☶|☶☶☶|☶☶☶|☶☶☶|☶☶☶|-\\\ ❚ ↑ /———⚇———⚇———\ section \———⚇———⚇———/ ``` If you have a cigar-shaped vessel, you can produce section by section by moving along while making progress. In any case where you would manufacture sections that you can not stack on top of (ok, it's space, there is no *top*, so: next to) each other, you would need an additional factory, completely different in size and shape from the first one, just to mount parts together. This would result in an additional step in production. If one step delays, the other factory is stalled. When a manufacturing yard would have to adapt (by transforming) to the size of the ship, it would loose time. Just compare the process to what Henry Ford did. Another aspect would be, that it would be unable to perform maintenance or upgrades on existing ships if the factory would have to adapt to the shape of the ship. Simplified: A cigar (or tuna) shaped ship can easily vary in size (even as upgrade), while any other shape will not allow an equally easy format for the yard. [](https://i.stack.imgur.com/TiRZb.jpg) *One example of bad, but cost efficient design: The [Reliant Robin (Wikipedia)](https://en.wikipedia.org/wiki/Reliant_Robin).* Shape boils down to: Money. It's simply not cost efficient in production. *Money is the reason for a lot of shapes that seem to be less practical than others, but are practical when your stakeholders want to see the most monetary output for their investment.* [[](https://i.stack.imgur.com/WBWig.png)](https://www.youtube.com/watch?v=QQh56geU0X8) [Answer] Another additional reason: they need the extra surface. Contrary to popular belief, space is not cold. Space is just empty, and that means that it has no temperature, and the ship cannot pass any surplus generated heat to the space other than radiating it. The issue is, in any closed system, any conversion of energy (from example from fuel to kinetic energy, or electricity, or light, or from food to chemical energy in our bodies) is going to produce some unwanted heat. And unless you get rid of that excess heat, your astronauts will arrive at their destination a little too much cooked to what is considered acceptable. So, maybe your machinery produces enough heat that you need extra walls to heat them so they may radiate the heat outside. [Answer] The spaceships not only travels interstellar spaces. It might do the take off and landing in an environment that has atmosphere or friction. [Answer] It's a combination of several factors, most of which have already been mentioned but I'll put them all together anyway, with some helpful analogies. ## 1. Aesthetics/Rule of Cool For this I'll use the analogy of a skyscraper. The most efficient design for a skyscraper, in terms of using all the available space, is a big tall cuboid. But you won't find many modern skyscrapers that look like that because big tall cuboids are *really boring to look at*. The Burj al-Arab, for example, looks like a giant sail. Freedom Tower tapers neatly along its edges. The Gherkin looks like a... gherkin. Alternately, look at cars. What looks cooler, a boxy, bulky Land Rover, or a smooth, streamlined Aston Martin? Actually, on the subject of sports cars... ## 2. Drag Reduction (got ninja'd by @tom on this one) You're right that friction isn't really a concern in space, but I'm assuming that at some point, your interstellar ship will want to land on a planet and then take off from it again. And when you're leaving or entering a planetary atmosphere - *especially* when you're entering - friction is a *very big* concern. Friction is (as far as I'm aware) what generates the massive temperatures that cause objects to burn up in our atmosphere, so unless you want your ship to disintegrate upon re-entry, streamlining - and decent heat protection - are very important. ## 3. Deflecting Foreign Objects As @nzaman and @Burki have already pointed out, an interstellar ship will be travelling very, very fast. Fast enough that hitting something even the size of a pebble could cause major damage due to the relative velocity. IIRC from Wikipedia (I'll look it up later when I have time), a 6g piece of metal hitting your ship at orbital velocity will leave a 3-inch crater... and your ship will be travelling a heck of a lot faster than orbital velocity. Also, going back to point #2... space junk. If we have it, other advanced planets probably have it as well, to a greater or lesser degree, and some of it will be too small to detect and dodge. A streamlined design will have two benefits here. First, it'll reduce your ship's frontal cross-section and thus reduce the chance of that evil space pebble hitting your ship in the first place. Second, you know how tanks have sloped armour? That's to increase the relative thickness: an object hitting a metal plate at a 45-degree angle has a lot more material to go through than if it hits it straight on. So it'll also reduce the damage caused by those tiny pieces of space debris, and increase the chance of them just deflecting off. ## 4. Saving Weight/Material Interstellar spaceships are, as you hinted in the OP, expensive. *Really* expensive. And the materials required to build them might be hard to come by. So you'll want to cut costs. That means that you'll want your ship to have the smallest surface area possible without compromising on the interior space, not just for aerodynamic purposes, but so you can use the absolute minimum amount of material necessary. This will also save weight, which depending on your propulsion system, might make your ship more fuel-efficient and save you even more money in the long run. So yes, there are plenty of reasons you'd want (or even *need*) your interstellar ship to be streamlined. [Answer] # Smaller Cross-section If your ship is long in the direction of travel and narrow in other directions, it means your ship presents a smaller cross section along its direction of travel. Some advantages include: * Fewer collisions with dust and other debris, and thus less wear on your hull, or less energy needed from your shields or navigational deflectors * You present a smaller target to enemies you are approaching or fleeing Given this design, there are also advantages to having your ship taper off at both ends: it means a greater volume of your ship is adjacent to the forward-facing or rear-facing hull. For example, this may mean you can mount a much bigger forward-facing laser cannon or deflector array or whatnot. [Answer] Everyone seems to have forgotten a single important principle. **Round is stronger than square** <https://www.youtube.com/watch?v=hUhisi2FBuw> Simple. Pay special attention to wall depth and required materials. Now why does it need a pointy front? It doesn't. It just looks cool. [Answer] I see at least three reasons: 1) One of the technologies being mooted at the moment for the ISS is a great big laser to blast orbital debris sufficiently to deflect it. So a smaller cross-sectional area in the direction you are traveling is an advantage for deflection. 2) For rotational artificial gravity, rotational symmetry matters, at least in terms of mass, as does having bulkheads that are parallel to the rotation so they work as floors. So in a rotationally-symmetric ship, at any point there'll be a circular cross-section, or similar. (Admittedly, you could instead have a large mass on one side, counterbalancing a large arm further out but with higher velocity, orbiting around the center of mass. The center of mass would remain stationary, which is important when you want the thrust to go through that center of mass. This design is way more of a pain in the ass and more unstable, though) 3) For any kind of static anti-radiation shielding around the ship, smooth lines with no spikey bits make the field easier to calculate and keep constant. [Answer] * The design wants to separate two components (e.g. power plant and passenger quarters) as far from each other as it is feasible. This gives a cylindrical hull, or perhaps a dumbbell. * The design uses a *technobabble drive* with limitations on the geometry. [Answer] For the same reason your eye is a ball. Vacuum. 1. Spaceships may travel in space but the space is filled with gravitational fields of different magnitude. 2. Also there are stars that constantly fill the space with many types of radiation that curved surface have larger probability of bouncing of. 3. The streamline design put less tensions on the joints and welds of the spaceship itself. It's also take better the movement of the material due to different temperatures (expanding and contraction) [Answer] ### Landing When you get to your destination, you don't know how much fuel you'll be able to get. So you have to carry landing fuel with you. Rather than carrying enough fuel for multiple trips, just land the whole thing. Once on the ground, you can easily go to and from the ship. You can walk. No fuel needed. Use solar panels, etc. and charge up the batteries on wheeled or tracked vehicles. ### Refueling I remember one of the old RPGs (**Traveller**?) had a streamlined option. They used it to fly down into a gas giant or ocean and refuel the fusion reactor. Without that, you had to buy fuel at a space station, which doesn't work so well for a generation ship. The point here is that if you get to the target star and can't find a suitable planet, this could help you move to the next star system. [Answer] Nobody has yet suggested the shape which needs dictate. The needs are to minimise the chance of colliding with anything of significant size, and to allow the people to experience gravity. The former, because at a fraction of light speed, encountering a grain of sand is akin to being successfully targeted by a nuclear missile. Not survivable. On the other hand, if it whizzes past a mere six inches away from your hull, it is harmless. Gravity seems to be a physiological necessity for human beings, and this is a generation ship implying that there is no way to cheat and store everyone in suspended animation. It is plausibly speculated that gravity is even more vital for a baby developing in its mother's womb, than for adults, to avoid developmental abnormalities. So the design will be a cylindrical central core containing reaction mass and main engines, and three or more long thin hulls attached to it with cables. The whole assemblage will rotate around the axis of the central core, creating pseudo-gravity in the outer hulls. Inside those hulls the experience will be similar to living in a ship if the water-borne sort, but without the waves. Lots of length, not so much width. Radiation shielding (against the radiation caused by impact with mere molecules!) dictates that most of the inhabited hulls be filled with reaction mass, and that this mass will be the last to be used during arrival. The inhabited bit will be at the back. The geometry is the easy bit, compared to everything else! [Answer] If your ship uses a light sail as you described then they want it streamlined to minimize its shadow. The more stuff you have poking out the more photons they block. [Answer] Much of course depends on your technology (e.g. the propulsion system and so on). For example if you travel through handwavium distortions, and the distortion is spherical, it makes sense to build a ship as a sphere extending to the limit of the available distorted volume. You could even place the most expendable materials in the periphery, so that in a pinch you can generate a smaller distortion and scamper away with your ship's core, leaving the outer layers of HMS Onion to distract an enemy or to fight to the last against whatever astronomical phenomenon you're fleeing. In some novels by [Mark L. Van Name](http://www.markvanname.com/) space Portals are circular in shape, so that you want a cylindrical ship as large as possible to use the whole Portal, and as long as possible to get the most material through. The need for some structural flexibility makes you end up with spaghetti ships (or ships that can *fold* into spaghetti for traveling). [Warshawki sail gravitic propulsion](https://en.wikipedia.org/wiki/Honorverse) dictates a double hammerhead shape and there's little that can be done about it. And collapsed matter gravity generators force you to travel [in the stem of large mushrooms](http://rads.stackoverflow.com/amzn/click/067157857X). --- If we make without handwavium propulsions and collapsed matter, and we *only* introduce relativistic speeds, then cylindrical shapes become almost a necessity. * when traveling at relativistic speeds in real space, without "energy shields", you continue to receive light from the outside on the whole ship surface, but your frontal cross-section receives the light with a strong [Doppler effect](https://en.wikipedia.org/wiki/Doppler_effect) compression. At not-so-low speeds this translates into a blue shifting of the light coming from the front. At relativistic speeds, the light of ordinary stars, but what's more, even *the cosmic microwave background*, will be shifted towards X rays and hard gamma, so much that it will not only irradiate the prow, it will start photodisintegrating its surface. Individual particles cannot travel at relativistic speeds for too long because they too incur this effect, leading to what's known as the [Greisen–Zatsepin–Kuzmin limit](https://en.wikipedia.org/wiki/Greisen%E2%80%93Zatsepin%E2%80%93Kuzmin_limit) (*which also holds for starships*, so they can only move so far between repaints - or ablative shield replacement). It makes sense to have as little cross section as possible. At low speeds, drag considerations lead to prefer a frontal cone or bullet shape to a blunt cylinder. Since the prow will need to be armored and made of radiation-resistant material (for lots of reasons that will probably be where the main water tank will be housed), a cylinder allows limiting the mass that needs to be lifted. * The ship will presumably need very powerful engines and they're likely to require lots of cooling, as well as to [emit lots of radiation](http://www.chris-winter.com/CATS_Quest/Nuc_Rkt.html); they'll not be Orion propulsors, but they might be something close. Both reasons suggest to deploy a long "tail" with radiating fins, and possibly place a shield between the body of the ship and the power plant / engine section. * the cylindrical passenger and cargo section allows maximizing the surface that, once spun (and counterspun) to produce pseudo-gravity, experiences the same acceleration. Possibly, the cylinder could be made up of a series of "donuts" linked to a central spindle. * having a cylindrical "payload" allows for a modular construction, simply lengthening the spindle and adding more donuts on it. In [*Slow train to Arcturus*](http://rads.stackoverflow.com/amzn/click/1416555854) the various donuts are actually separated worldlets capable of limited independent navigation. The donuts themselves could be further made up of cylindrical sections capable of limited rotation along their axes; this way the donut rotation and the ship's thrust both accelerating and decelerating could be compounded to give the desired gravity acceleration, and have the cylindrical sections rotated in such a way that the acceleration is perpendicular to the floor (a variation of this mechanism is presented in J. P. Hogan's *Endgame Enigma*). In the end, you get something not unlike this: ``` <||=######====|====<<<< ``` which could be (charitably) defined as *fish-shaped*. # Some reasons *against* cylindrical shapes which (while true) I still don't buy * "spherical shapes better redistribute pressure". True, but cylindrical shapes aren't so far behind; high pressure gas bottles are actually cylindrical, so their better packing factor must be enough to offset any structural advantages the spheres may have. * "ease of construction": a surface plate for a spherical shape can go anywhere on the surface. True, but so can a surface plate for a cylinder, except for the top. Actually, there are reasons why the top is better constructed of a different shape, different alloys and so on; having a spherical shape means that *all* the surface needs to be able to withstand the onslaught in the direction of the motion. And if a part of the sphere is internally different, this kills all arguments for symmetry. As someone else already observed, cylinders are actually **easier** and cheaper to construct on a volume basis, since they can be *extruded* from the shipyard. And as I myself observed, cylinders are easily modularized. Spherical wedges would be much more awkward. [Answer] Only to impress investors who judge everything based on art and know nothing about the design elements of performance engineering. I don't think it really matters though what shape a ship is before it impacts with an object the size of a baseball or passes through a cloud of ice crystals as small as grains of table salt while traveling at a significant fraction of the speed of light. [Answer] I don't imagine an interstellar ship *would* bother much with a streamlined body design. I believe there are multiple reasons, but the one I'll muse about here is mass. The more massive the ship, the more energy it would take to accelerate it anywhere near relativistic speeds. What would be the point of any real trip between stars if you couldn't reach relativistic speeds? As far as we know, most or all of that energy--in the form of some kind of fuel--would need to be transported on the ship. That's bound to take up some room, and of course the mass of the fuel itself must also be accelerated. Pushing an object to the actual speed of light would require an infinite amount of energy. Pushing an object to, say, half the speed of light would merely require a gigantic, massive, currently unfathomable amount of energy. So we're talking about a problem where a vessel carrying a finite amount of fuel needs to produce an effectively infinite amount of energy (grossly over-simplifying). All told, the mass of the ship is going to be an absolutely fundamental engineering problem requiring incredible technological breakthroughs. Adding a fancy streamlined extra outer hull would add mass that the ship simply cannot afford. On the other hand, who's to say that humanity won't come up with some kind of infinite energy drive. Maybe we'll be able to pull power from subspace, or use a matter/antimatter reaction involving di-lithium crystals, or harness power from a black hole or magnetar through some kind of subspace conduit. Or since the subspace conduit will probably be a wormhole, which may well be a black hole, maybe we'll be able to channel mind-blowing amounts of energy from magnetars or gamma ray bursters via blackholes. Or we might develop a warp drive that compresses and expands space around the ship so it skips across the universe faster than light could travel conventionally, but without phasing out of sync in time, and making the mass of the ship effectively irrelevant. That would be cool, and the ship could look cool just for the sake of looking cool. And, who's to say that super-streamlined outer hull couldn't be made out of a feather-lite yet surprisingly flexible and strong, one-atom-thick carbon lattice of some kind? [Answer] The interstellar space is a vacuum, but not complete (100%) vacuum. There is a super rarefied gas with density > 0. So the faster the space ship travels the denser will become the contrary gas flow and the windage (incl. friction) will increase. Although the most of the gas is plasma (ions) and it is good to have a shield against it. [Answer] The sections with air pressure would be most economically shaped like a balloon Also halving the cross section would half the chance of hitting interstellar debries. So if everywhere onboard is pressurized, and we reduce the cross-section: we get hotdog spaceships Though, if we assume the engine puts out a large amount of force at a single point (as other people mentioned), then this will mould our shape in much the same way as the carriage of a hot air balloon moulds the balloon into a tear drop ... And a tear drop is kind of streamlined, at least back-to-front But since we dont have galaxy travelling spaceships, we can bet they will to some extent be based on technology/physics that we also dont have . Maybe they will travel on gravitational waves, and thus most optimally be shaped like surf boards? [Answer] I think that it's because they look good but also it's science fiction. When it becomes real it will look as unusual as a solar sail or something similarly unique. [Answer] ## Filling the envelope defined by some field Supposing that even in the future no hull material is itself strong enough to endure high speed collisions/friction implied by the scale of space and space travel; it might be that some kind of protective field must be used instead. A protective and/or time-and-space-bending field, in fact. The apparent streamlining of the ship may be the result of making the most efficient use of the space within the envelope defined by such a field; or it may be the shape from which it is most economical to project such a field. This would be slightly different from the pulp sci-fi generic "shields" as used in combat. Those would probably be blunt; having to provide adequate protection in every direction. [Answer] Scientifically reasoned, all of the above could be true...a long streamlined ship with crew at one end and ?power source? at other could protect crew, dislodge space rocks, and be aesthetically pleasing. Gas atmospheres would slow anything but a streamlined ship...there are also vast clouds and pockets of gases in space. Structurally, a slim, triangular shape is physically the strongest shape, and more able to nudge aside space debris. Strength is needed, and a universal geometric shape, or a needle-like design seems best. Form and function exist in geometric designs we know, and a disc/triangle makes universal sense (even a Borg-cube would suck in our atmosphere without a special field eliminating mass, inertia, drag, or resistance). [Answer] It wouldn't. Obligatory link: <http://www.projectrho.com/public_html/rocket/basicdesign.php> Your interstellar space ship would likely not look like anything you see on earth. Not a ship, not a plane. The closest resemblance would be an oil rig. There would be various parts connected by pure structural beams. If you insist on having it somehow streamlined, you need to **invent** a reason. One could be some kind of force field that protects or works as a warp bubble or whatever. This could, by physical laws, be a sphere or oblong sphere and enforce a restriction that leads to a specific shape. [Answer] **It was designed by an intelligence incapable of conceptualizing Euclidean geometry** Extra-dimensional visitors, or maybe an AI that lost (or never had) the ability to calculate simple geometries. ]

[Question] [ The military of (insert nation here) has finished training its latest asset: an adult dragon. Let's call him Private Firestorm. He's got everything the top brass wants from a soldier: he's professional, loyal, skilled, follows orders to both the letter and the spirit and goes along with his fellow soldiers. Some of Private Firestorm's abilities include: * He is big and strong enough to carry a battle tank (or something of equivalent weight or size) in his arms while flying without becoming noticeably slower. * He is intelligent enough to understand orders and carry them out on the same level as a skilled soldier. * His scales make him immune to small arms fire, and only sustained fire from the largest of rounds (.50 cal) on a very small spot have any chance of hurting him. * He is able to carry things strapped to his underside by way of heavy-duty bands or cables. * The military developed communication gear that fits to his size; the gear is on the same level as that of a regular soldier. * He can shapeshift into a human, and aside from his eyes (which look the same as his dragon eyes) is indistinguishable from a regular human. When shapeshifting into this form he will be wearing whatever he was last wearing when in this form prior to turning back into a dragon. In this form he has physical capabilities like that of a similarly-sized human. * He can breathe fire, but not in his human form. * The military developed rations that are of extremly high calorie value, reducing the size of Private Firestorm's daily required nutrients to the size of a regular military ration. Dragons are known in the world, but thus far no large scale military operation has taken place around them (because they're smart enough to not mess enough with humans to warrant this). How would Private Firestorm likely be deployed into combat? As a front-line soldier? As a transport? As a support unit? As a member of a black ops team? Or as something else? [Answer] All of his other abilities are dwarfed by the "shapeshift into a human" option, which would make him an invaluable weapon for surprise attacks and assassinations. Even if his dragon form isn't tremendously powerful in combat, it doesn't need to be as long as the enemy isn't actually expecting a shapeshifter. Modern physical security is largely based around preventing insurgents or enemies from bringing a weapon *close enough* to harm a VIP, and follows in rough concentric circles: you can't bring your strategic bomber into the country at any time, you can't bring your light aircraft into the city when the VIP is there, you can't bring your car into the city block when it's closed off for Big Event, and you can't enter the building where the speech is happening if you set off a metal detector (etc.). Being able to *physically transform* into a dragon lets the soldier skip over several of these layers of security. He can get into the hypothetical square with a thousand other citizens to cheer and wave placards or whatever, or past an airport's metal detectors and into the supposedly secure zone, and suddenly pull a weapon equivalent to a light fighter aircraft out of his pocket, long past the "ring" where the local security forces can do anything about a weapon of that scale. He can then kill whomever he wants before disappearing again into the night, as all of the evidence is removed by the reverse transformation. Technically this is similar in concept to the first time someone wore an explosive vest to an event, bringing a powerful explosive weapon within the "ring" people had assumed was limited to knives and handguns. But the scale and versatility of the dragon form as a weapon (flight, defence, ranged attack) make this far more disruptive - even ignoring the fact that in the real world, suicide bombers still do disrupt the "rings", because screening for them in public is mostly impractical. This isn't limited to assassination (real-world militaries don't generally do that very much, since it messes with diplomacy), but it's the most obvious example of somewhere where the security depends on keeping heavier assailants at a distance (e.g. attacking a military base by getting up close then transforming *might* work, but military bases will have larger guns on-site that can attack him even if he's too fast for scrambled jets). Public sections of government buildings, for instance, may check for concealed handguns, but don't generally have a plan for what to do if someone gets a *tank* inside the secure area. [Answer] **Logistic support** Boring as hell, but that's the most realistic option. Most other uses are replaceable by other means. Why send a dragon on a special ops mission when highly trained operatives already exist that can do the job better and more quietly? If he's a private, then he's inexperienced, so he's potentially a liability in the field. Why use a dragon for assassinations when a UAV launching a missile can do the same job? As the *first* dragon, he's a propaganda asset. Which means you really don't want him to get killed. There is exactly one thing he can do, however, that cannot be replicated by current technology, and won't put him in too much danger: > > He is big and strong enough to carry a battle tank (or something of equivalent weight or size) in his arms while flying without being notably slowed down. > > > A C130 Hercules transport can only carry 20 tons. A Chinook can only carry a lousy 15 tons. An Abrams is about 60 tons. He can carry *that*, in his arms without being slowed? That means he can carry maybe 2-3x more with a suitably designed harness, moving slowly? You've got a super-heavy lifter that can operate without an airstrip. That's a pretty big deal. You can drop in full armoured units in, whereas previously you can only get in by ship at a port, or the long way by land. Oh and you only need to feed this guy normal sized rations? Hell yes. [Answer] **Science**. Well, a big tough lizard is cool, but shapeshifting should break the law of conservation of mass, creature of this size shouldn't be able to fly, and so on. Studying such a creature would likely lead to breakthrough in fundamental physics, and this would allow creation of new, incredible, weapons. Manipulation of mass, manipulation of gravity - these things are *way* more valuable than "one guy that can shapeshift and fly with a tank". To waste such a precious creature on combat activities, you should have a very desperate army, or an army without any researchers (rebels, maybe?), or maybe the dragon itself wants to fight but doesn't want to be studied. [Answer] **TL;DR:** Anyway the military wants to deploy him, but watch out for anti-aircraft methods. In today's environment, the biggest challenge to a dragon as you describe would be anything with significant range. If we assume the dragon has decent natural armor (scales and whatnot), then small arms are more of an annoyance. He'll need to be wary of rocket propelled grenades, anti-aircraft artillery, and aircraft, basically all the things modern aircraft have to concern themselves with avoiding, only he won't be as able to counter them. On an open battlefield, he can be deployed as part of the shock troops. In this case, the shock being the "Aaahhhhh! Dragon!!!" factor from the opposing troops as well as the physical shock of him landing. Or drops a tank on someone. He can roast opposing soldiers and damage tanks and artillery with his breath (melt, if hot enough). He makes a good reconnaissance unit as well. [Flying predators](https://www.ebiomedia.com/what-animal-has-the-sharpest-eyesight.html) have some of the best eyesight on the planet, so we can safely assume a dragon is going to have impeccable vision and can identify and distinguish targets at a phenomenal distance. Since he has communication equipment, the dragon can radio troops on the ground, aircraft on approach, the command post, or even ships. Your dragon can also do rescue missions. The fear factor of a fire-breathing dragon hovering above you would be high. Ground troops attempting to raid a building would think twice while the dragon is perched on top or circling. His size will play against him in one role I can think: urban combat. A dragon's greatest strength is flight, but door-to-door combat excludes flight as a possibility. He'll be vulnerable to ambushes. That being said, he would make a great ally when it comes to emptying a building of hostile forces. He just looks in a window and exhales. All being said, the dragon you describe can be deployed as any role you want. However, such an entity would be considered a nontrivial asset. If you only have one, you would want to protect it from destruction. It's the same kind of issue the U.S. has with the [B-2 Spirit](https://en.wikipedia.org/wiki/Northrop_Grumman_B-2_Spirit) in that it costs so much to build that they really invested in not losing it. [Answer] **Propaganda** Since he is not invulnerable, he can be and will be destroyed by the enemy in a confrontation. Heavy weapons are absolutely not rare in the field, missiles and precision-guided bombs can pretty much hit anything, and these are usually designed against armored targets. His wings ought to be less protected than the scaly body, offer significantly greater surface to attack and if his wings are damaged during flight, the resulting fall would likely kill or disable him, at least for long enough to give the attackers a chance for another attack. Though you did not define the range or power of fire breath, I assume it does not work against armor. His flight speed is also not specified, just assumed to be slower than a fighter jet. These two severely hinder his fighting abilities against pretty much anything except infantry, light vehicles and non-fortified installations. Bombing might be an option, but anti-aircraft fire would be very effective due to his (assumed) slow flight speed. But he has a very strong asset: Psychology. His size and form makes people think him stronger and more dangerous than he really is (as established in the previous section). This makes friendly soldiers to appreciate his presence and support, just knowing that there is a **freakin' dragon** on their side makes them much more brave. This also works in inverse, enemy soldiers would much less like to attack any object when there is a non-zero chance of encountering a **freakin' dragon** there. He must have also cost the military huge amounts of money, since he needs unique, one-off equipment specially designed and developed for him (like the comm gear and the rations). Putting the above together, you have a singular soldier that represents enormous investment, has significant but not overwhelming combat value, while providing a huge morale boost for friendly forces and reducing enemy morale. ... Just like *Captain America* (at least in the movie, I'm not familiar with the comic variant) So I'd guess the military would use him exactly like they did with Steve Rogers, send him on tours along the training fields and frontline troops to bolster their morales, create short movie clips to show allies, citizens and enemies alike in order to establish the thought of military superiority. Of course, the enemy would make it a top priority to hunt him down to remove this asset from our team and to be able to boast with killing a **freakin' dragon**. The more intelligent enemies would perhaps like to learn some of the secrets required to have one of their own. They would send spies to try to convert him, telling about the real or imaginary evildoings of our team, or just plainly inciting him to stop acting in movies while watching his comrades and bodyguards die in real combat and the repeated assasination attempts, but take matters in his own claws and venture out to the battlefield disobeying orders where they have set up a trap for him. [Answer] No question: **Special Ops**. For working with local resistance units, he would be enormously reassuring, as long as religious objections don't make him The Devil. For LRRPs (Long Range Reconnaisance Patrols), he has the ability both to destroy enemy forces who stumble across the patrol and he provides instant extraction if the situation goes pear-shaped. Everybody on the team carries a harness and line to hook on to him once he shifts. An MBT runs, typically, in the range of 60 to 70 tons, so he can carry a *large* team. For raids, he provides the "Aaah! Dragon!" factor that Frostfyre mentions, enormous distraction value as the rest of the team scurries around attaching demo charges to points of interest, and (once again) extraction capability. Plus, he can do all sorts of damage all on his own, between setting things on fire and throwing heavy equipment around and breaking it. What he's not suitable for is conventional assaults. If he tries that, he's going to run into anti-tank missiles sooner rather than later, and if a .50 cal round can hurt him you don't want to think about what a shaped-charge warhead will do. [Answer] Sell him. As he is a loyal soldier, he'll do his duty even if it is "go chill in this zoo or with this trillionaire. Use that money to buy multiple planes, which are faster, better armed, and armoured. [Answer] > > When shapeshifting into this form he will be wearing whatever he was last wearing when in this form prior to turning back into a dragon. In this form he has physical capabilities like that of a similarly-sized human. > > > That offers a novel capability. What he's carrying essentially gets stashed outside of reality, to be retrieved when he shapeshifts again. This could be used as a stealth mechanism to smuggle items or otherwise transport goods unobserved, or a storage mechanism: the "man" could carry, say, medical gear or delecate instruments, and they are out of danger during fighting. That can also smuggle "top secret" information or artifacts— say, he has new code books or Enigma wheels in his coat pocket. Not only is the dragon form good for transporting them, but if captured or subdued the secret items will not be found. [Answer] Let's address each of your bullet points one at a time: > > * He is big and strong enough to carry a battle tank (or something of equivalent weight or size) in his arms while flying without being notably slowed down. > > > This would make him a great asset for transport, but only in a drop-off sense, since there's only one of him. It also means he can wear armor and carry significant additions in firepower, so that means upgrades are a possibility. Picture a dragon covered head-to-toe in tank armor, with a mounted turret or ICBM on his back manned by another (brave) soldier. And no, the armor isn't superfluous if it can help him withstand heavy artillery fire or ballistic attacks. > > * He is intelligent enough to understand orders and carry them out on the same level as a skilled soldier. > > > This greatly improves his capabilities on the battlefield - not only can he be a transport, he can be a well-defended scout with his own escape plan, assuming he can be trained in camouflage. He doesn't have to outrun interceptors - he just needs to know when they're coming, land, and find someplace to hide (much easier with his human transformation below). > > * His scales make him immune to small arms fire, and only sustained fire from the largest of rounds (.50 cal) on a very small spot have any chance of hurting him. > > > This would make him a very capable shock troop for regular combat - essentially he'd be his own tank. It would also make him invaluable for raiding key locations, where he's less likely to run into encampments or vehicles that could pierce his armor plating. > > * He is able to carry things strapped to his underside by way of heavy-duty bands or cables. > > > Again, troop or tank transport. Also makes the possibility of using him as a mobile artillery or missile launching point more viable. > > * The military developed communication gear that fits to his size; the gear is on the same level as that of a regular soldier. > > > Assuming he can talk, this greatly boosts his potential as a recon tool. It also means he can receive orders and warnings from local radar systems, letting him know when a genuine threat (like an attack fighter or a tank) is coming his way. > > * He can shapeshift into a human, and aside from his eyes (which look the same as his dragon eyes) is indistinguishable from a regular human. When shapeshifting into this form he will be wearing whatever he was last wearing when in this form prior to turning back into a dragon. In this form he has physical capabilities like that of a similarly-sized human. > > > If he can transform such that what he's carrying as a dragon is still on him as a human, that'd be insane, but also insanely useful for transporting large hardware without having to use up much space. Even without that, being able to make himself much smaller means making himself a much easier target to hide if he runs into trouble, and with a pair of shades he'll be able to infiltrate places more easily without being detected, making him a potential assassination or infiltration tool. > > * He can breathe fire, but not in his human form. > > > Unfortunately, other than upping his value as a shock troop and possibly posing a distraction for anti-dragon aircraft, this doesn't improve his capabilities much. Unless the fire is hot enough to seriously damage aircraft. If it is - handy way of ambushing an aircraft. > > * The military developed rations that are of extremly high calorie value, reducing the size of Private Firestorm's daily required nutrients to the size of a regular military ration. > > > Which is good, because otherwise the upkeep on him would be *insane*. And as others have noted, you could also use him for... **Morale/Recruitment** A dragon is *very* recognizable, and very cool. It'd definitely boost any troop's morale to know a dragon is on *their* side, and would make for an excellent image in a propaganda poster. [Answer] > > * He is big and strong enough to carry a battle tank (or something of equivalent weight or size) in his arms while flying without being > > notably slowed down. > > > A dragon that can carry even a WWII sized tank in the manner which you state is going to be huge. We are talking as big as a large airship(think Hindenburg.) It is one thing to have the strength to pick it up from the ground, it is another to have the strength and power to fly with this as though it were nothing. A more realistic statement would be that the dragon can take several soldiers with equipment with out hinderence, and some light vehicles with effort. > > * He is intelligent enough to understand orders and carry them out on the same level as a skilled soldier. > > > Typically dragons have been shown as arrogant and would be unwilling to subject themselves as common soldiers for any length of time. A large par of training is the drilling of technique and process so that in combat soldiers can be counted on to react predictably. This type of training is monotonous and designed to break and then reform a human spirit. In order for this to work on dragons you are probably going to have to have a dragon cadre for training. Dragons are more likely to learn and subordinate their urges if they are being lead by other dragons. > > * His scales make him immune to small arms fire, and only sustained fire from the largest of rounds (.50 cal) on a very small spot have > any chance of hurting him. > > > I would assume you mean that his scales make him resistant to small arms fire. He is also going to be resistant to shrapnel and small explosions. Most dragon legends also make them immune to fire (able to swim in lava). It is not the size of the bullet that is dangerous to the dragon but the energy potential it carries. A small caliber bullet that has been propelled at a high rate of speed can do as much and often more than a larger bullet at the same speed. There are in development now mass projection weapons(rail guns). These use energy to propel small bullets extremely fast. They are impractical in today's military because their is no real target that needs them. Tanks are vulnerable to explosive ordinance that the dragon is going to be resistant too. If we had this type of enemy then I can see these types of weapons being developed faster and being deployed in defense. > > * He is able to carry things strapped to his underside by way of heavy-duty bands or cables. > > > This is probably going to be less efficient and impractical when compared to modern heavy lift helicopter capabilities. This is going to be limited to use in special operations where the flexibility of the dragon soldier makes it more practical. > > * He can shapeshift into a human, and aside from his eyes (which look the same as his dragon eyes) is indistinguishable from a regular > human. When shapeshifting into this form he will be wearing whatever > he was last wearing when in this form prior to turning back into a > dragon. In this form he has physical capabilities like that of a > similarly-sized human. > > > This is his strongest ability. He can train and interact with human soldiers and would be a huge asset in a special operations unit. Especially if his resistance to fire and weapons extends to his human form. > > * He can breathe fire, but not in his human form. > > > A great shock weapon but less useful than one might think unless the goal is the complete destruction of a target. A more realistic use is to cover a retreat or extraction. Humans steer clear of fire so a well placed breath of fire that blocks a chase path is going to be more useful than setting the first few chasers on fire. > > * The military developed rations that are of extremely high calorie value, reducing the size of Private Firestorm's daily required > nutrients to the size of a regular military ration. > > > Having the field rations is great, but one thing I remember from my time in the military is that extended periods on field rations takes a huge toll on morale. Hot meals and real food are as important to a soldier as good boots and a functional weapon. So to keep your dragon units effective you would need to be able to provide a regular supply of a satisfying meal for the dragons. The larger the dragons are the more food you are going to need to provide them. Modern technology and weapons have rendered most of the standard dragon's advantages moot. So the dragons role is going to be mostly limited to special operations. But as a super special operator the dragon could excel. [Answer] Breeding Program. Assumptions: Firestorm cooperates... and disregarding bio-compatability and ethics. If you put Firestorm in a breeding program then you get more Dragons after... let's say... 12 years. Yes, child soldiers, but we're disregarding ethics here. Then, you reinsert your New Dragons into the breeding program. With the average conception chance, 20-25% a month, spread out over, 1000 women? The chance of no Dragon Babies is around 10 to the -100th power... A *very* small chance. So, after a few decades, the country could be around 75% Dragon? That is, assuming that the other Dragons don't notice and shut the program down... but then again it's a Black Project, done in underground bunkers, and all that secrecy stuff. And modern military weaponry can easily handle even a torrent of Dragons... Also, the sperm donations wouldn't impact his "shape-shift into a human" abilities, so he's still a viable combat unit while participating in this program. [Answer] I'm quite surprised at the assumptions people have made here. When I imagine a dragon breathing fire, I imagine the plasma-blasts of a Night Fury or the flammable saliva of a Monstrous Nightmare (species of dragon from the How To Train Your Dragon movies by DreamWorks). With that kind of firepower, Private Firestorm's fire becomes a little more useful - he can replace a small missile or napalm. If his saliva is flammable (one of the most realistic mechanisms for dragon fire), they could simply take it from his mouth and use it in other weapons. Also, people have said a dragon of that size would be hard to conceal - what colour is he? Dragons are nearly always depicted as predators, so presumably he has natural camouflage. Perhaps he can even change colour. Also, being a predator would make Private Firestorm an excellent assassin (even if dragons don't hunt by stealth, he could at least be a hitman). He could also be used in diplomatic proceedings. No matter how tough a politician is, they are going to be off their game if they know the man they're talking to can turn into a dragon as large as a cargo plane. Not to mention the eyes - they would freak everyone out. due his inability to take damage from anything more powerful than small firearms, Private Firestorm can't simply be used as a wrecking machine on the battle-field (except perhaps against the army of an LEDC, as they would not have as many/as advanced weapons.) Private firestorm can be used for transport (away from the danger zone), negotiation (face-to-face) and as a secret weapon against poorly-equipped armies. Perhaps the most effective use of a shapeshifting dragon would be to deploy him as a normal soldier, in human form, and keep the dragon part secret from the enemy. And when the SHTF, he can turn back to dragon form and wreak havoc. This would boost his fellow soldiers morale and crush the enemies morale (the survivors would come back gibbering). [Answer] In direct combat the private isn't that useful, not in modern day. We have weapons far more devastating then what his scales can protect against that can fire from far away and out maneuver him. In a fight against a fighter jet or any of our big weapons of war he simply goes splat too quickly to be more then a brief tactical surprise. He's pretty strong to infantry, but modern wars are decided less and less by infantry then by big expensive guns that overpower him. Leushenko answer is great and close to what I would have answered, his ability to hide as a human and thus 'sneak' in pretty massive fire power where it's least expected is powerful. It's less about raw power, more about being able to extend it to places your enemy does not expect and would not allow it. It's also important that he can do it in a way that the enemy doesn't have time to get any of their big guns, like fighter jets, to him before he disappears again. However, the answer didn't go in to how fully to exploit that power, other then assassination which it mentioned was usually politically less advisable. Actually assassination of semi-important figures may still be a good option. You can't assassinate the head of state, but taking out some of it's high ranking military officers is only going to cause a bit of political difficulty, the tactical advantage of taking out those leaders can be worth it. For that mater taking out lower ranking logistical or leaders at any front right before a major offensive would be useful and generally considered 'fair game', though most of them will be in bases and as said before bases tend to have fighters and other weapons of war near by, making it a risky play since you may not have time to get away safely before they can get their stronger weapons readied to use against you. However, All the above is just an example of a more general concept, guerilla warfare. Guerilla warfare is probably one of the hardest types of wars to fight, the US had massive technological, numeric, and logistical superiority over Iraq when it invaded, it still left years later with a decent number of lives lost and no real headway because guerillas just couldn't be killed. However, the one limit to guerilla warfare is that they can't get any big guns, their limited to small arms and occasionally small explosives, enough to kill *people* but not enough to do much major damage to the military weapons. Private firestorm is different. He is able to do guerilla warfare, as a person he can disappear at any time into a crowed, but he also brings big enough fire power to destroy whatever he chooses to. He can be a threat to larger military hardware, with far less risk then regular guerilla operatives, then disappear back into a crowed. In any place where infantry is used heavily, which now of days is usually to control areas with civilians like cities, he is very powerful. He can crush military solders and fade away. So long as he makes sure to always pick a place where he can attack and kill fast then get away back into a crowed *before* the fighter jets and tanks can reach him he is pretty safe. He can single-handedly stop military occupation of any area he is at, and if he picks his targets right could probably strike at lone higher value targets like tanks, jeeps, supply conveys etc, to score larger victories. In fact after awhile he becomes a terror weapon that works just by scaring the soldiers into never going anywhere because at any moment a fire breath instrument of death may show up to crush them. Of course when he starts this tactic three counter-tactics come up. 1. Start looking with the guy with strange eyes. This...won't work as well. There are too many people, and too many easy ways to hide his eyes to make it practical to find him in any decent crowed of people. Plus, if infantry find him he can always go dragon, crush them, then fly away and hide again; so long as there isn't a larger weapon at war beside the infantry men who ask to see his eyes he's still somewhat safe; and do you really see solders being suicidal enough to insist on trying to identify someone that will kill them if they succeed and then likely get away with it? 2. Start creating a better system for tracking him when he flies away, using small drones, satellites, and quick responders you can probably manage a system of tracking him in dragon mode and seeing exactly where he 'goes human' and getting both infantry, to deal with screening humans to find the dragon, and larger weapons like fighters to that area quickly. Modern military can use this tactic to make it far more dangerous for him to go dragon anywhere due to the difficulty of loosing his trackers long enough to disappear into the crowed. 3. Start arming people with the means to deal with him. Keep fighters and tanks at hand when your doing operations the dragon would likely want to interrupt. More importantly, arm your solders with explosives that can take out a dragon, enough people carry hidden RPGs and your dragon's going to start to be in danger even from 'easy' victims. However, option 2 and 3 can be fixed easily enough, keep him on the move. Put him in a situation to attack a few people at location A, then hope him on a truck and drive him to a front on the other side of your country to do the same thing there tomorrow. With rapid transportation he can move around a massive area. With such a huge front to attack from it's no longer practical to try to arm everyone with weapons, or surveillance, equipment to deal with him. Combine with that picking areas of opportunity well and you have a pretty lethal combination. Take out the few guards on a Dam over here and you can threaten an area with liquidy death. Destroy the power lines and generators over another town and leave the base blind and unready to deal with your infantry front. He can be pretty disruptive, though it takes a pretty extensive logistics to figure out where he should be traveling, and some of this can be done by smaller elite cells almost as well as he would do. But there is one step better, move him away from the front lines entirely, send him on a counter offensive. Have him travel to your enemy countries home; surely you can figure out some way to sneak one operative past their boarders; or just have him bust his way in through a border somewhere and then hide. Once inside the territory he is actually quite safe. Past their front lines they won't have the big weapons of war, the things capable of killing him, so there aren't many things that are a major threat to him; other then being spotted and tracked so well then he can't lose (or destroy) his trackers in the time it takes to fly a fighter from a base a ways away from him (and even then, the enemy is going to be apprehensive firing missiles at a dragon flying right above a crowded city of their own civilians... Now if your evil you can start a terrorism campaign that would be very effective, but at that point assassination is an option to you and well...your be pretty effective until every nation declares war on you. (though...if you arrange to say he is awol terrorist and *not* supported by your nation perhaps you can get away with some of it). However, even if your not evil you still have targets to attack. The military already agrees that there are strategic targets that are fair game for attacks even in civilian areas. Any place that manufactures weapons of war will be a valid target, for example. Power plants I believe can be, training grounds if you find any that aren't too defended by bases with fighters, etc. He can simply drive around the nation, attacking completely random strategic infrastructure locations at seemingly random. Make sure to never stay in one place for any length of time, and to always have a plan for how to 'go human' and get away quickly before helicopters can be set up to start following you (if you are followed by helicopters he can destroy them, but since they would be civilian police it's getting to be a little more diplomatically grey; best to take them out without killing fliers when possible). The only thing he really needs is sufficient source of raw money to be able to buy bus tickets to get around. He needs to travel long distances between targets to keep everyone guessing, but that isn't to hard to do in a modern country. He still has the danger of being tracked long enough that the police can get a jet to him. The biggest danger here is if he is tracked without realizing it, smaller drones he doesn't realize are following him. If he can't change his human appearance pictures of him will circulate after awhile, but he can hide his face and still get around pretty well, the country is just so huge that there are too many people he can disappear behind. If he manages to keep this up long enough without being caught eventually the terror aspect will result in people afraid to work on building weapons of war because he may show up and destroy their building. That affect can do far more harm then his actual attacks do, it's all psychological. The important thing would be to make sure he attacked only strategically 'far' targets to keep the moral high ground of "were not terrorists, were just attacking valid targets with the weapon we have while trying to minimize civilian loss of life". He *should* try to minimize lost of life, important diplomatically, but he still works as massive psychological warfare even if he is doing that. I can't say how many infrastructure buildings he can get to before someone manages to track him, but frankly it won't take many before he starts to really cripple the military infrastructure and force them to bring a disproportionately big part of their military back simply to assure their civilians that they have people ready to deal with the big scary threat. [Answer] Here's a strategy: Have Private Firestorm fly above any enemy fortifications or castles. Then have him turn into a human. He will fall and land without hurting himself because he is super tough, even as a human. When he lands on the fortification or castle, he needs to get to the center of the building or trench or whatever. The guards are too busy looking at the army in front of them that no one will notice. If they do, the Private has a smoke grenade to conceal himself. Then, he turns back into a dragon. The massive increase in size will blow the walls of whatever structure he is in to smithereens. Then the Private turns to a human, gets to the top of the structure without resistance from the now-unconscious soldiers, turns into a dragon, and flies away. Here is a similar technique used in Angry Birds: [](https://i.stack.imgur.com/zENfa.jpg) You can repeat this process for as many fortifications as the enemy has. Without any open fortifications, the enemy will have to either fight in an open field where the Private could mow them down, or all hide in a closed building with a ceiling and openings to fire from, the consequence with this being that the Private can destroy the ceiling, bringing it down on top of the enemy. ]

[Question] [ While playing old games, I encountered a friend I knew from [SciFi series](http://memory-alpha.wikia.com/wiki/Merculite_rocket) and [games](http://masteroforion.gamepedia.com/Merculite_missile) alike, the *Merculite* missile. While thinking about what *Merculite* might actually be (and linking it to a mineral from the planet Mercury in my head), I had a basic idea for a short story about a freighter transporting a mineral that is not dangerous while hot (but still non-liquid), but get dangerously explosive if its temperature drops below a certain point. This might not work out at all and does not necessarily require hard science, but I was wondering if there are any known components or minerals that exhibit such behaviour. My basic school and university chemistry tells me that it is counter-intuitive as any exothermic reaction starting once the temperature drops below a certain point would heat up the mass again, but maybe there are some weird chemical or physical things that may allow for this, like 1. It really simply explodes once the temperature drops too low or 2. it is only stable *above* a certain temperature and thus seperates itself into two or more components that form an explosive liquid that explodes once it reaches a critical mass or 3. I have absolutely no idea. Are there any weird substances with such or similar attributes, are such substances even possible with our current understanding of physics and chemistry or would I need to use a pseudoscience mineral? **UPDATE** Wow! I'm really impressed and thankful. Please give me some time to pick the answer - I'm not sure if I should pick the one that I like best, but that goes a little bit in a different direction than my original question, or pick the one that answers my original question best. [Answer] # Use Iron's allotropic forms Iron has a wide variety of allotropes. Two interesting ones are [austenite](https://en.wikipedia.org/wiki/Austenite), with atoms aligned face-centered cubic (FCC) and [hexaferrum](https://en.wikipedia.org/wiki/Hexaferrum), where the atoms align in a hexagonal close packed (HCP) form. Here is the phase chart for iron:[](https://i.stack.imgur.com/vF5Ch.jpg) Both Austenite and Hexaferrum are denser than the Ferrite that they will phase transition into at lower temperatures. Thus, as the material cools (at constant pressure) and the phase change occurs, the material will expand (much like water does when it freezes). In the case of hexaferrum, this transition will happen quickly. An additional interesting property of these allotropes is that they have differing solubility for various materials. Austentite is can dissolve much more carbon than ferrite, so it is used to make high carbon or stainless steels where you want some other material to dissolve in an iron solution. The last piece of the puzzle is that hexaferrum is not well known. It requires a pressure of ~10 GPa to maintain. One interesting property of it is that it is martensitic, giving it excellent magnetic properties. Ok here is a technology idea that I've been saving up for a while; I'm going to share it just with you. What if you wanted a material that could serve as the 'core' of a fusion generator that had the following properties: * Acts as a neutron shield * Does not readily undergo nuclear fusion * Can be magnetically compressed * Hydrogen readily dissolves in it What I just described is hexaferrum. You could (using a little pseudo-science perhaps) use it as a 'core' of a fusion reaction, with the hydrogen fuel dissolved in the hexaferrum core. The core shields the outside from most of the radiation and compression from powerful magnetic fields keeps the core at high enough pressure that fusion can occur and it stays solid. # Your ship has a hexaferrum core that is cooling down and about to explode. Fusion stopped or was stopped in the core, due to sabotage, accident, or routine shutdown. However, the hexaferrum is cooling down too fast. When the hexaferrum core reaches the critical temperature, it will suddenly increase in volume by 20%, causing it to fracture and spit out all the irradiated elements in it. Also, all the hydrogen dissolved in it will come out of solution, potentially destroying the ship. [Answer] **Water** [](https://i.stack.imgur.com/TemfV.jpg) ok, beer. Watery beer. An explosion occurs when matter changes so as to occupy more volume. We are used to the explosions where a solid or liquid suddenly changes into a gas, which takes up loads more volume. When water freezes, the solid form takes up more volume than the liquid. If confined in a space which cannot deform, the expanding ice can explode the container. Expanding ice can break stone. No-one is going to make grenades out of freezing water. But this might work in your story. A space going water tanker is super plausible. What if environmental control fails and it starts to freeze? I am envisioning the ruptured freighter in a ball of ice like these beers, trails of sublimating vapor drifting off into space. [Answer] **Polymorphic explosives**. Materials with exact the same chemical composition can exist in several *phases*, *allotropes* or *polymorphic forms* which are only different for their crystal structure. One well-known example is diamond and graphite:  *Image by Rob Lavinsky, Wikicommons, CC-SA 3.0 license* **Diamond** ist one of the hardest substances, highly transparent, a semiconductor and a good heat conductor. **Graphite** in contrast is soft, black and completely opaque. Both are essentially carbon. This polymorphism is also existent in [explosives](https://www.nrl.navy.mil/content_images/08FA1.pdf). TNT is well known that it has two polymorphs: a yellow, stable variant and an orthorombic orange variant, the orange variant changes into yellow if heated. The paper counts other substances, picryl bromide has e.g. five known polymorphs. It is also known that some polymorphs are even disappearing and appearing: Turanose was once liquid at room temperature, the current form is solid.[Paroxetine is a substance which caused a patent litigation because a new, unpatented form (hemihydrate) occured and even more vexing for the firm, seed crystals forced the patented form (anhydrate) into the unpatented form.](https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4479028/) While I am not aware of an example, it is possible that heating a substance will cause a reaction, the reaction creates a new substance which is in this phase harmless but will change into a highly explosive phase if cooled. While not an explosive, [phosphorus](https://en.wikipedia.org/wiki/Phosphorus#White_phosphorus_and_related_molecular_forms) is a good example. The white variant is highly toxic and extremely flammable and self-igniting, heating it (!) transforms it into the much more stable and non-toxic red form. [Answer] You could leverage some macroscopic properties, such as stresses which form as an object cools. [Prince Rupert's Drops](https://www.youtube.com/watch?v=xe-f4gokRBs) are a fascinating example. During cooling, they form a head which is virtually indestructable and a tail which, if tapped slightly, causes the entire drop to explode as it releases the mechanical forces pent up inside it. A Prince Rupert's Drop suspended in a vial of nitroglycerin could be an excellent real life analog for the fictitious mineral you want. If the tail is tapped, the whole drop explodes with great force, and that would likely provide enough energy to set off the nitroglycerin. Obviously you wouldn't want exactly that structure, but you might be able to construct something which fractures as it cools embedded in a matrix which, when initiated by the fracture, undergoes a true explosion. Something involving a temperature sensitive protein might work, if biology is fair game for your explosive. [Answer] This sounds a bit like [methylcellulose](https://en.wikipedia.org/wiki/Methyl_cellulose), a substance that can be used to create a gel with an unusual property: it sets up when heated and melts when cooled. It can be used to make such things as marshmallows that remain solid when hot, but melt when they cool down. Kind of the opposite of how normal marshmallows work. [](https://i.stack.imgur.com/6PDA3.png) [](https://i.stack.imgur.com/hY65Z.png) [(source)](http://mom.girlstalkinsmack.com/family/modern-industrial-chemicals-(part-5)---%E2%80%9Cmelts%E2%80%9D-as-it-cools--methylcellulose---hot-marshmallows.aspx) A methylcellulose gel won't explode on its own, but it could be part of a trigger mechanism of a larger explosive device. Perhaps there's some high explosive dissolved in the gel that could be detonated when the gel melts. Or perhaps the gel is the explosive- it's suspended in a box made of an [alkali metal](https://en.wikipedia.org/wiki/Alkali_metal), such as [cesium](https://en.wikipedia.org/wiki/Caesium). When the gel melts, it becomes able to contact the cesium, which then reacts exothermically with the water in the no-longer-gel, producing large amounts of heat and hydrogen gas in the process. [Boom.](https://www.youtube.com/watch?v=m55kgyApYrY) You'd probably also want to have some more conventional explosives in there (such as TNT), as the water-cesium reaction is limited by how quickly the two materials can mix. And if you're looking for a material that is inherently explosive when cooled, some of the other answers here are closer to that. But methylcellulose could certainly be used to set off an automated self-destruct mechanism of some sort- when the power goes out, the heater built into the mechanism stops working, and the block of methylcellulose cools and melts, dripping onto a piece of cesium and setting off a stack of TNT. [Answer] # Hydrazine Perchlorate mixed with Hydrazine There are several real world chemicals that explode when cooled enough. For example, Triazadienyl Fluoride explodes as soon as it reaches -196 C. (1) However, it also explodes when it is warmed, when it is bumped, or when it is looked at funny. I think the most plausible example for your rocket to be carrying is Hydrazine Perchlorate mixed with Hydrazine. This solution was once investigated as a high performance rocket fuel, so it fits your setting. As the Hydrazine freezes out, the concentration of Hydrazine Perchlorate in the liquid part should increase, and if it increases too much, the whole lot will explode. (2) 1. <http://blogs.sciencemag.org/pipeline/archives/2008/10/21/things_i_wont_work_with_triazadienyl_fluoride> 2. Ignition!: An informal history of liquid rocket propellants. Page 78 [Answer] There's one option that comes to mind that might interest you: highly saturated solutions. Have you ever seen a sodium acetate heat pack? They're sold in various outdoorsy stores, and they just look like a little plastic packet filled with fluid, with a small disc inside. When you activate the disc, you see this: [](https://i.stack.imgur.com/OvTpJ.gif) This surprising action is due to a natural phenomenon called **supersaturation**. Supersaturation is a term used to describe a solution that has more dissolved solute in it than should be possible. One way to achieve this is with heating and cooling, because solvents tend to be able to dissolve more solute at higher temperatures, due to some quirk of chemistry that I don't currently understand. A supersaturated solution is in an unstable state; certain impulses will knock it out of its careful equilibrium and return it to a more usual state. The little disc in the pack contains one of those impulses; a small crystal of sodium acetate that can start a crystallization cascade. Those heat packs work because they contain more sodium acetate than the surrounding water can dissolve. In order to prepare them, you heat them up, which allows the water to absorb all of the sodium acetate, and then when you cool the pack back down the water and sodium form a supersaturated solution. When the crystallization process is triggered (by the little disc or simply by a hard shock), the sodium acetate crystallizes out of the water, which releases enough energy to comfortably warm your hands for the next half hour. I think this could apply quite well to your particular idea. A ship with a hold full of some kind of concentrated solution could be quite safe so long as the solution is kept warm (perhaps it was produced on a volcanic planet, originally), but were its temperature to fall, the now-supersaturated solution could pose quite a problem once its energy is released. [Answer] Mainly for the sake of morbid curiosity I'll mention one of my favorites. Steel balls that are used in grinding mills (SAG mills) apparently are heated and their surfaces hardened while grinding, and stresses induced in the steel ball itself. When taken out of the mill and allowed to cool, they sometimes explode (and I'd imagine a large, exploding ball of steel would be a tad dangerous). Such explosions may have even killed people. [Here's](http://www.eng-tips.com/viewthread.cfm?qid=116115) a discussion of exploding SAG mill steel balls... (NOTE: Side benefit is you get to keep a straight face while discussing exploding balls). > > ruble3 (Mining)30 Mar 05 08:23 Glad to be here! That particular > incident happened in the early nineties-I hadn't worked in process > plants before & was skeptical until I heard it from the horses mouth > -still not sure why it happens - only refernce I could find was a > case on a legal website where a family sued the mill after a worker was > killed by an exploding ball - they blamed a 'manufacturing defect' ?? > -still looking > > > tomrivet (Chemical)1 Jun 05 00:59 We have exploding balls quite a bit. > The current thoughts are that the outside of the > ball gets work hardend at a high temp (say 40C). Then the ball shrinks > as it cools... > > > arunmrao (Materials)1 Jun 05 13:01 The balls explode > due to builtup internal stresses. There is a volumetric expansion as > some of the austenite has not completely transformed into martensite > during heat treatment. It is this residual austenite which causes > explosion of the balls. I have seen crazy things happening,imagine on > a dark night!! > > > TurinShroud (Mining)1 Jun 05 16:59 I work at a copper > mine that has a SAG mill with 5" balls. When we go in the mill for > liner inspections, you can feel balls exploding underneath your feet. > Last year my boss got cut in the ear by one. > > > I always thought that the balls exploded due to the internal stress > generated by the outside cooling (and shrinking) faster than the > inside. If we wait long enough before entering the SAG mill, the > balls are no longer cooling and stop exploding. > > > Just yesterday, one of the operators said the balls can explode even > after a long time. I had never heard of the balls exploding after > they have cooled down. Has anyone else out there ever heard of the > balls exploding after a long time? > > > If the exlosion is due to differential cooling, I just don't see how > they could explode after they have been out the SAG mill for more than > a few hours > > > [Answer] According to thermodynamics, more ordered states are favoured at lower temperatures, so essentially what you are looking for is a system which increases in volume as it becomes more ordered, which is unusual. As mentioned in another answer, this happens when beer turns to ice, but the volume change is quite small. Another process is as follows: Hydrogen sulphide generated in oil refinery desulphurisation processes is converted to sulphur by the Claus process: ``` H2S + 1.5O2 (air) -> SO2 + H2O 2H2S + SO2 -> 3S2 + 2H2O ``` Sulphur made in this way contains short chain like molecules of the form `H-S-..-S-H`. As it cools, these decompose to form ordered stable `S8` rings with the release of `H2S` gas. Vessels containing molten sulphur made by this process must be properly vented to ensure they do not overpressure and explode as the sulphur cools. Ihe `H2S` (hydrogen sulphide, rotten egg gas) presents additional hazards as it is smelly and highly toxic. A quick google search found this document discussing the handling of this type of sulphur, see pages 4-5. <http://www.trimeric.com/assets/15v07-mcintush-molten-sulfur-storage-tank-loading-and-vapor-ejection-systems-review.pdf> EDIT: a better reference <http://pubs.acs.org/doi/abs/10.1021/ie50477a047?journalCode=iechad> The other source of sulphur on Earth is via mining, including surface deposits in the craters of semi active volcanoes. I think it quite plausible that sulphur mined on a planet with a high atmospheric pressure such as Venus would contain these `H2Sx` molecules. As an aside, note that the best place in the solar system for mining sulphur is probably be <https://en.wikipedia.org/wiki/Io_(moon)> though it has only a trace atmosphere so I would expect the sulphur there to be fully degassed. [Answer] As indicated by Thorsten S.’s answer, there are solids that have different phases. I'd like to add examples where a phase-change can be induced by cooling. Some typee of steel undergo [cryogenic hardening](https://en.wikipedia.org/wiki/Cryogenic_hardening) treatments. At about −185 °C more austenite transforms into martensite, the phase change propigating at the speed of sound once it starts somewhere in the metal. Now alloys designed to make use of this will not change size significantly, warping and exploding. But other steels *could* have that problem. Then there is the remarkable metal [nitinol](https://en.wikipedia.org/wiki/Nickel_titanium). It *does* undergo profound changes, and can have two shapes “memorized”, one for hot a d one for cold. This works cia the same kind of crystallization change, triggered by temperature and pressure inducing austenite-to-martensite and martensite-to-austenite transformations. A totally different mechanism might be caused by the separation of a mixture. Atoms of type 1 might slip inside the crystal lattice of 2, making it take up no space. But shrink the lattice a bit as it cools, and atom 1 is forced out. These can work together, with different crystal phases permitting other atoms to move in or not, as with carbon and iron. [Answer] This answer is slightly off-topic as it is not about a crystal or other chemical substance that explodes when it's allowed to cool down too much. However, this answer is about an object that does explode really violently if it's allowed to radiate away too much energy. And it's a really useful thing for a scifi setting: A miniature black hole. If you have a miniature black hole of around 600000 tons of mass, it will explode within 3.5 years. You must constantly feed such a black hole to keep its energy output at manageable levels. If you fail to do so, it will blast you to pieces: If my calculations are correct, it will evaporate an energy equivalent to 233 tons of mass within its last second of life. I have my doubts that our planet would survive such a huge explosion, it's really far beyond anything the largest nuclear weapons can do. Why would a space transporter use a black hole? Well, for propulsion! (See the wikipedia article on the [black hole starship](https://en.wikipedia.org/wiki/Black_hole_starship) for reference.) Turns out that small black holes make for quite efficient, high power reactors that can be fed with *any* fuel. Trouble is, the smaller the "black" hole, the brighter it gets. Now, the wikipedia article on the black-hole-starship puts the size of a useful black hole around 606000 tons which would evaporate within 3.5 years. Such a black hole would need regular feeding to keep it at manageable power levels. If you fail to feed it fast enough, it will blow up, destroying anything in the vicinity. Especially the transporter that used the black hole for propulsion won't survive this. As I said, this answer bends the rules of the question slightly: While the black hole does loose energy, it does not get colder. On the contrary, it gets hotter. Nevertheless, it does fit perfectly into the idea of having a space transporter that just explodes when it's unattended for too long. Especially with providing a really good reason for the dangerous object being within the transporter. [Answer] ## A two or three part mineral might do it In real life, such a mineral on Earth wouldn't last long because there's so much regular temperature changes. Also, highly reactive elements tend to have reacted a long long time ago (ex. fluorine is always always found bound to some other element.) Temperature changes got me thinking about phase changes. * Plasma to Gas: Nope. * Gas to Liquid: Probably not. * Liquid to Solid: Quite possibly. All of these transitions are endothermic. Most ignition sources for explosives are exothermic; electric current, fire, lower speed explosions (and resulting shock). Fire as an initiator won't work since it too is an exothermic reaction which could push the temperature of the mineral back above the danger temperature. Let's see if we can find an ignition source that can still work at lower temperatures but gives a nice boom too. ## Piezo-electric [Piezoelectric](https://en.wikipedia.org/wiki/Piezoelectricity) materials generate a small charge when they physically deform. This property could be leveraged to generate an ignition current. ## Mineral Matrix Piezoelectric crystals + explosive + compression material = Boom! General Process: 1. Above critical temperature, the compression material doesn't squeeze the piezoelectric crystals enough for them to develop a charge. 2. At critical temperature, the compression material begins to condense from a liquid or gel into a crystal. These crystals exert pressure on the piezoelectric crystals embedded in the explosive. 3. As freezing continues, the piezos snap into smaller pieces or snap back into their original shape thereby releasing their charge into the surrounding matrix. If enough of these piezos snap back at the same time, they might generate enough current to detonate the explosive. The compression material actually makes this mineral more dangerous as explosives in confined spaces tend to react more powerfully than if detonated in the open air. ## Conclusion Despite a semi-plausible explanation above, this highly lucky matrix of materials is unlikely to exist. It could be engineered by humans, possibly, but highly unlikely for Ma Nature to shake her chemistry set and have it go boom this way. [Answer] You might also consider something like a [stud blaster](http://www.physik.uni-wuerzburg.de/video/waermelehre/grundlagen/filme/g11ausdehnbolzen.mpg) (if that's the correct tanslation of "Bolzensprenger"). The usual length contraction of one component due to cooling creates enormous forces on the overall structure until it fails in an explosion-*like* event. [Answer] Others have alluded to this, but water can "explode" if it cools too fast. It is one of the few known molecules which expands as it transitions from liquid to solid. If it freezes fast enough, it will first form an outer shell of ice, which will eventually burst, sometimes violently, as pressure builds up from the center freezing. While this probably does not provide enough of an energy output for the type of explosion you are envisioning, who is to say that there is not some other compound out there which exhibits a similar behavior on a greater scale? Playing in the realm of space travel gives enough room for any number of exotic materials to have been discovered. [Answer] ## Nuclear criticality You can have a [pile (literally)](https://www.google.com/search?client=safari&rls=en&q=nuclear%20pile&ie=UTF-8&oe=UTF-8) of fissile material, with space amongst the material intended for a [moderator](https://en.wikipedia.org/wiki/Neutron_moderator), which will not have critical mass without that moderator present. This can even [happen naturally](https://en.wikipedia.org/wiki/Natural_nuclear_fission_reactor). It is considered excellent reactor design to use a moderator which doesn't work unless it's reasonably cool. That is how most non-Russian non-Canadian reactors govern themselves. If core power exceeds demand, the water coolant will boil more, increasing steam voids (bubbles), which are a poor moderator compared to the liquid water the reactor is designed for. Power is passively reduced. We've barely scratched the surface on potential reactor designs. We have played with small modular reactors, which are factory-made and sealed, and not for the user to tamper with. Conceivably the transport instruction might be "keep the reactor hot enough for the coolant to be in gaseous state" otherwise it will go critical. Especially if tech is readily available that makes this easy. ## It's not the reactor You won't get a nuclear explosion from a runaway reactor. It might not even run away owing to the moderation method. But it would emit a heck of a lot of gamma radiation! (it would not be inside its massive biological shield; you wouldn't ship that, since it's plain concrete and easily made locally with indigenous materials.) Anyway, *your other cargo* might not appreciate massive doses of gamma radiation none too much, and *that* might be what explodes. And that is just the kind of [dumb](https://en.wikipedia.org/wiki/ValuJet_Flight_592) shipping [mistakes](https://en.wikipedia.org/wiki/Asiana_Airlines_Flight_991) that [happen](https://en.wikipedia.org/wiki/UPS_Airlines_Flight_6) in [the real world](https://en.wikipedia.org/wiki/Texas_City_disaster). [Answer] **Plasma of reactive molecules** This answer is as esoteric as my other beer answer is prosaic. Imagine two gases which combined and heated will react - let us say hydrogen and oxygen. Now convert the hydrogen and the oxygen to a completely ionized plasma and combine them. The ionized plasma state will prevent the typical chemical reaction and as long as the plasma is kept hot and charged the gases will not react. On cooling down the hot hydrogen and oxygen will react in the typical energetic way. I am trying hard to think of some advantage this mixed plasma would have over 2 reservoirs of gas... Going even more out on a limb, consider intra-particle interactions in a highly charged hot plasma. These particles do not bump into each other any more as the electrons are all stripped away and moving independently. The positively charged nuclei repel each other. Imagine now a plasma composed of highly ionized hydrogen matter and antimatter. It is stable as long as everything is highly charged. If the plasma cools, hydrogen atoms will try to reform hydrogen gas, and if the 2 atoms are matter and antimatter there will be an explosion. A plasma would be a nifty way to contain antimatter because you could contain it with magnetic fields. I hereby name this mixed hydrogen antihydrogen plasma "zoom juice" because you could release small quantities of it and use it as fuel. [Answer] Uranium should do the trick. Implosion type nukes work by compacting fissionable material that normally isn't critical. They do it with a non-nuclear explosion, but guess what would also shrink a hunk of uranium? That's right, thermal contraction. Plus, it's easy to explain why a freighter would be transporting it if you make fission energy common in your universe [Answer] Basically anything that forms crystal or amorphous structures upon solidifying which bear *tension* (think of a prince rupert drop...) AND become more brittle with cooling. Steel has been mentioned in other posts, and indeed quenched, untempered steel is known to potentially shatter or break quite energetically when provoked.... ]

[Question] [ So I and two others are working on a time machine, and I accidentally press a wrong button and whoosh, all my friends and I are in 17th century Salem, Massachusetts. Nobody sees us appearing out of thin air, so we aren’t burned to death on sight. But we are all wearing modern day clothes as we weren’t able to change. I’m wearing a pair of jeans and a hoodie, my female friend is wearing leggings and a crop top, and my other friend is wearing a letterman jacket. We don’t have any food or supplies, so we must go to Salem as it is the closest town. It isn’t during the witch hunt time, but it’s very close, about 1691. How would people back then most likely react if the saw people dressed that way? [Answer] **Zippers!** Zippers have not yet been invented. Do keep that in mind. If there are any obvious zippers, this will be a source of wonderment. People were a lot more sharp eyed than you think back then, so they aren't going to miss that. Hoodies come in many different styles--some have zippers in the front, some are pullovers. The ones on pants might not be noticed but any front and center would be. EDIT: If you want a year on these they were introduced in 1893 at the Chicago Wold Fair, but they weren't produced commercially on a widespread basis until 1917, and even then they were only on boots and used to seal tobacco pouches. It wasn't until the 1930s that they began to be used on clothes, and that was mainly pants. **Snaps!** A letterman's jacket features snaps. I don't know if you realize this but...snaps were not patented for at least another hundred years. While they have been intermittently used in history, in this time and place, it is pretty likely that in Salem they have never seen one. EDIT: The Chinese invented these way back in 210 BC, but they weren't commonly used, nor was the usage widespread. In Europe it wasn't until about the 1830s and 40s that they began to appear on theatrical costumes for quick changes, and then the usage moved to gloves. These early snaps were not reliable and tended to rust, and therefore were not all that popular. In the late 1800s and early 1900s the design was improved and began appearing on work clothes mainly, and on cowboy style clothing as well. In 1690s Salem they would not exist. **Lycra/nylon/stretch** Any material with stretch to it is a goshdarn modern MIRACLE. Women were really, really good at eyeing fabric and qualities at this time. While your leggings and crop top girl might be branded as a slut, a kind woman that finds her would want to dress her immediately, knowing that she would be hurt otherwise. Then she would question her manner of dress for certain. Next, she'd be wanting a closer look at the fabrics. Actually, she might even offer clothing of hers to borrow in exchange just for a closer look at those leggings. Seriously! EDIT: Most stretch materials are a product of the 1900s, and the most usable are invented/widespread after 1950. **Blue Jeans** So, the first use of the words blue jeans are like in 1790. But it's possible that blue work fabric might have been around for longer than that. Certainly, the thickness and type of fabric is one that your Salem natives might recognize as work pants. EDIT: The indigo industry has been working to undercut the woad industry in Europe for about 200 years. There was a ban on using it for quite some time that's lifted in the 1600s. During the 1600s the major producer of it in the Americas was Spain, not England. England was just getting into the business and it wasn't until the 1740s that it was grown in South Carolina by the French. In the 1700s it was big business, but in 1690, in an American colony established by the English, it wasn't as common as you might think--blue was produced mainly by woad, not by the distinctive indigo. Workers in Europe used similar material (mostly dyed brown or dark), but for a long time indigo was considered a luxury dye. Workers in Italy and Spain were more likely to use a blue jean type material. The late 1600s and early 1700s is precisely when there was this shift of it being more common--but in an American British established colony in 1690, the indigo blue jean material is odd. **Shoes** You have forgotten shoes. Let me just say that if anyone is wearing sneakers...people will be mesmerized. Rubber has not been invented. Basically, everything about a sneaker is the result of an industrial age. The rivets, metal, plastic, rubber, colors, everything about them is wildly exotic and beyond the current tech of the day. **Socks** Yep. depending on the type of sock, yes, your socks are astounding. If they have stretch, they are a miracle. Color, pattern, and everything else should be taken into account. Machined socks are...quite incredible. There's only one seam in the toe, and sometimes there isn't even that depending on how they are made. The weave is sometimes terribly fine and some socks are even a little fuzzier on the inside vs. the outside, even if they are thin. EDIT: Do some research on socks of the day, and stocking styles. Socks during this time were much higher, partially using the knee to keep them up. Decide on the exact style and type (because there's tremendous variation) and compare that to what was fashionable and available during this time. Any elastic stretch material, which is common in today's socks would be a big deal. Keep in mind that what's common in the 1700s and 1800s is not at all what they would have in 1690--machine works and the industrial age in Europe radically changed the world of socks and everything else very quickly. The Puritans favored wool socks. Using stays, ties and other things to keep socks up was common. Some socks had a built in string you would tie to keep them in place. They liked over-the-knee socks best, and would use the buckle or ties, aka garters, on their pants leg to keep their socks from slipping. **Details, details & Class** You've painted a general picture of what they are wearing, but it's the details that will also matter. Are there any neon colors included in anything? Is there red? And if so how bright/dark? (Contrary to popular beliefs, Puritans did wear color, it was just fairly muted in tone.) Do the leggings end in lace? Lots of leggings have a lace band at the end or decorative detail--lace was outlawed for certain classes. Just saying leggings or just saying a t-shirt doesn't cut it. Anything with words, as one commenters pointed out--something like the Nike phrase "Just Do It!" would be very, very odd to these folks. The jeans, if they are ripped, if they are light blue or stone washed, or distinctive dark indigo -- these are details that will have an impact. The recently lifted Sumptuary laws in England are a specific point of contention for Puritans. Sumptuary laws told certain classes what they were and were not allowed to wear. See, just before this, in the Renaissance a lot of fabrics and colors became available to the lower classes and to upstart merchants. It upended society, because prior to the Renaissance you could tell who was a quality person by what they wore, at a glance. So, laws were put in place to prevent people of certain professions from wearing certain things which, though they might be able to afford them, implied a higher class status. By the mid 1600s a lot of these were finally repealed, as they didn't work much anyway. But your Puritans don't think the way the rest of Europe did. Order, status, calling, all those mattered to Puritans. So while Europe was taking Sumptuary laws off the books in the 1620s, and getting more and more elaborate in dress, us Americans were [getting stricter](https://www.atlasobscura.com/articles/sumptuary-laws-puritan-fashion-colonies-modesty) about what we allowed or not, and outlawing slashed sleeves. By 1690, courts in America were finally a bit more relaxed about actually prosecuting a lower class lady who wore a silk kerchief (though I think she was still arrested, just not tried). The person you'd want to meet is someone such as Hannah Lyman...By 1690 she'd be a middle-aged or old woman... > > IN 1676, HANNAH LYMAN WAS in trouble. She was among three dozen or so young women who had been summoned to court: They had flouted the laws of the colony of Connecticut by wearing silken hoods. Among these “overdressed” women, Lyman was, apparently, the most rebellious and strong-willed. [She appeared in court wearing the very silk hood that she had been indicted for donning](https://www.atlasobscura.com/articles/sumptuary-laws-puritan-fashion-colonies-modesty). > > > The sneakers will mark you as wealthy, but the jeans will mark you as workers. You could be from a far land with different customs, but you can bet there will be questions. Lots and lots of questions and people will pay close attention to your answers as well. Your folk are wearing a mix of class indicators, which means that people will immediately want to categorize them. During this time in Europe there were people who dressed beyond their status, however, the ones who most commonly mixed high and low in a bizarre way were often pirates. Saying that you are from Europe and that this is the new fashion might work though, because Americans really expected all kinds of bizarre fashions, changing very quickly from their perspective, as they are cut off from European centers of fashion. [Answer] Their reaction strongly depends on how you behave and act. If you are smart enough they may help you and spare your lives. Your clothes would look odd even in the 50s of the previous century. If you are creating a time machine I hope you are clever enough to realize that. Else face the consequences described in others' answers. Your wisest action plan may be: 1. Get naked and burn your clothes (or bury them somewhere if you may need them later). 2. Seek help, pretending some brigands robbed you, leaving you naked under the sun (or the rain). Your likely pale skin will hint you are all gentlemen not used to work under the sun, and would probably make them forgive some odd bodily features you may still have (first thing that comes to mind is your female friend may have some waxing in the deep South...) [Answer] You and your male friend are wearing clothing that will be seen as extremely exotic, but not a problem in and of itself. They're obviously a variation on the "pants and a shirt" that's been acceptable male attire for centuries, but different enough from everything they've seen that you don't fall into any obvious social group (though you're clearly not upper-class). Your female friend, on the other hand, is in serious trouble: "leggings and a crop top" will be treated as if she's running around naked. Your best hope is to convince people she's a madwoman rather than a (underdressed) prostitute. (This is assuming all three of you are light-skinned. If any of the three of you has obvious African features, it'll be assumed that they're a runaway slave wearing stolen clothing. New England's famed abolitionist sentiment is still a century in the future, so the "runaway slave" will be held while people search for their master, and the other two will be imprisoned for assisting a runaway.) [Answer] A better route would be to avoid the Puritans if at all possible and seek out the Native Americans instead (in this place and era, perhaps the [Narragansett Tribe](https://infogalactic.com/info/Narragansett_people)). Although by this point the Aboriginals would have little reason to trust the white man, coming as a small, unarmed group in obvious distress will make them much less wary, and in general, unless you give them some reason to think otherwise, they will likely be willing to offer the hospitality of the tribe. Since you would already be having difficulties with language and customs with the Puritans, the exotic spectacle you put on with your clothing and language (and possibly artifacts in your pocket) will likely mystify and amuse your Aboriginal hosts, rather than trigger disgust or fear. With the Puritans you are close enough to trigger an "[uncanny valley](https://infogalactic.com/info/Uncanny_valley)" response, while the tribe will see you as just another, if slightly odder, version of the settlers. Diligently learn the language and customs, and gratefully offer to trade your clothes for the sorts of clothing they wear (which is much more practical for the environment and climate anyway, you will be wet a lot of the time and I note no rain gear, and once it gets cold you will freeze to death). [](https://i.stack.imgur.com/CtNip.jpg) *Narragansett meeting the Puritans. The leader does not seem amused* [Answer] I guess this quickly turns into a bottomless pit of (possibly dangerous) awkwardness... If you were not seen initially, hide your female friend and send one out to get supplies (clothing). While, as I suspect is true for humans in general, groups of people quickly turn into dangerous stubborness, fired by beliefs and suspicion and such, meeting a single person to overcome your (or rather your females friend's) initial clothing issue might turn out to be not entirely chanceless. People were able to think for themselves at that time, after all. Still, how would you go *explain* yourselves? You are most likely not acustomed to the language and the dos and donts implied, making that even harder for your group. Being under some sort of military service could help with the male clothes. Finding a tailor could help, they might even be interested in the fabric if they are open minded. But, apart from your clothes (and general style and behaviour), opening your mouth would deem your group being even more exotic (with 'exotic' being the best outcome I guess)... Update with some additional thoughts: Finding a tailor could very well be worth a try since they might actually be willing to trade in turn for your clothes (being very sophisticated in quality for that time). Otherwise, as stated in other answers, being robbed is probably the most feasonable story to tell, trying to save your (preferrably initially hidden) 'wifes' decency by getting some clothes, while looking robbed yourself (ripping your clothes etc., hiding some of the more modern elements of it). That is also a good reason for having no money or trade! I think it would be wise then to choose people that would understand being...well, poor. A farmer's wife could be someone who has pity for your female friend. Asking a fine gentlemen could easily backfire on you being dirty beggars... [Answer] Well it looks like, you have landed your selves in the middle of the festival of corruption known as the Salem Witch Trials. And as you can predict being in that time you can predict that it would be a fun time to break the rules but as for your clothing well your female friend would be the one to suffer the most. I doubt she would be called out as a witch but some disciplinary action could arise from such revealing clothing as leggings and a crop top, she may even be accused of prostitution or trying to seduce the men. As for your male it would be considered weird only way it would give away you were not from this time period is if it was a brightly colored hoodie. Despite common belief the Puritans didn't constantly dress as if they were going to a funeral everyday, they wore color clothing (as colorful as was feasible at that time) so your biggest problems would be to brightly colored clothing and the crop top and leggings. [Answer] Your female character would probably end up in the pillory, or be sentenced to hard labor. [](https://i.stack.imgur.com/yWAql.png) Your male character could possibly face either being publicly flogged for associating with such a woman of ill repute, or be "ran out on a rail," possibly after being tarred and feathered. Contrary to popular belief, a tarring and feathering was not comical for the person receiving it, but rather a very painful scalding from hot tar. He could expect to be in a high level of discomfort for several weeks and possibly develop infections and disfiguring scars. [](https://i.stack.imgur.com/4dFNl.jpg) [Answer] **You would be seen a foreigners** Common folk did not have much knowledge of the world outside their country/society until very recently. This is a time when travel is hard and expensive. Never mind video, photos have not even been invented yet. Very few of the people can even read. You might speak English, but you have an odd choice of wording and possibly accent given the three century gap. Add in your odd clothing, and you will probably be labeled a Frenchman or Spaniard, come to invade England's righteous colony. At which point you will probably be executed. [Answer] Give the girl the hoodie, so you have a shirt and jeans. Now hope that your shirt is solid coloured, preferably long sleeved, and your shoes aren’t too distinctive if thouroghly muddied. I would suggest giving your female friend some jewelry, so you can use it for trade. Asume you did that, you can go into town with the jewelry, and find a jewellers shop to sell it. Having done this, acquire clothing more ypical of the setting. Maybe claim that you are siblings, as this might seem less odd. Say your clothing has been damaged by travel. Get new shoes for yourselves, unless yours are leather, as it would be enormously odd otherwise. Take the clothing back to your friends, have everyone change, and continue. As others have mentioned, the fabrics and or snaps and zippers will be priced highly, and you may be able to sell them. [Answer] **Whores, Transvestites, Sinners, and maybe a Witch** > > I’m wearing a pair of jeans and a hoodie, my female friend is wearing leggings and a crop top, and my other friend is wearing a letterman jacket. > > > Being that its 1691 Puritan occupied Salem, witchcraft I am sure would be everyone's go to reaction for this scenario. While witch craft is indeed plausible I do not think it would necessarily be the first reaction. In order to be accused of witchcraft there would have to exist a perceived air of the supernatural about your character. Attire alone does not generate such suspicion. However attire did lead to a whole bunch of other horrible assumptions and treatments back then. > > my female friend is wearing leggings and a crop top > > > **She would be considered a Whore** In those days even the sexually liberal attire of the French consisted of heavy full body dresses. While the crop top would be acceptable to the French the form fitting leggings and short dress would be considered fairly risqué for the times. Now consider this in an ultra restrictive puritan setting where lavish clothing was considered a sign of immorality and your friend would quickly be written off as a whore. Now what they would do with a whore is a little ambiguous and not singular but certainly extreme: * Likely a few unwanted aggressive sexual advances and maybe rape (if you are lucky) * Branded as a whore * Stripped and beaten publically * Certainly breathtakingly strong misogynistic remarks * hung * Turned over to the magistrate (which basically is all the above and worse[exotic torture... the iron pair for starters]) * publically whipped If you are extremely lucky you will happen upon a convent or strong merciful religious family and if you play your cards extremely well they will take you in as a lost sheep and help you find Jesus. To which you will graciously accept with full penance if you ever wish to see the light of day unharmed. > > my other friend is wearing a letterman jacket. > > > If your other friend is a man he would probably get off scot free. He would probably get treated as a foreigner and potentially perceived as a dandy because of his luxurious attire (the colors). The puritans would likely treat him some form of contempt for his lavish attire but that's about it. If she is a she then it would be the same as the next: > > I’m wearing a pair of jeans and a hoodie > > > **You would likely be considered a Transvestite Sinner** In the 1600's and well into the 1800's women were forbidden from wearing mens clothing for multiple reasons. Ignoring the political reasons, I will focus on the religious reasons: > > [Cross-dressing](https://en.wikipedia.org/wiki/Cross-dressing) is cited as an abomination in the Bible in the book of Deuteronomy (22:5), which states: "A woman must not wear men’s clothing, nor.." > > > Now we might consider today that prostitution is worse than cross dressing however this was not that case back then. Back then prostitution was in some ways an accepted trade(yes revel in the irony from the above). Whereas, cross dressing was considered an "abomination" an unnatural act, basically right up there with sodomy (A HUGE Sin at the time). Punishments would similar to what the whore would face with some differences: * Potentially far less chances for rape as your 'manly' appearance would be more engagingly offensive than suggestive and enticing. Though there is the off chance off actually being sodomized out of someones ironic sense of justice. * Much higher chances for sexually related torture and mutilation * long stays in prison and/or the pillory. * Less likely to find an understanding family or convent As with all punishments back then, they are largely influenced by public sentiment. Severity can be anywhere in the ballpark from verbal admonishments to insanely brutal acts. In many ways you would be much better off stripping naked and running screaming naked into town claiming you were set upon by highway men and robbed of your assets. Pretty embarrassing but its plausible and beats the litany of horrific outcomes. [Answer] They would probably be horrified and think you are witches and demons sent to corrupt them. Telling them you "come from the future" will only make things worse. You'll probably all end up dead. As mentioned the best course of action is to burn all your clothes and pretend you were robbed by brigands. [Answer] In late 17th century Salem, the Salem witch trails took place many people were killed because of being suspected witches. If you brought any form of new clothing with you and you showed up in an unknown device, they would probably treat you like a witch. This would mean that death is near certain. Another comment states that "you would be thought to be a foreigner." This is not the case because the people from Salem came from Europe a few decades earlier. This would mean one elder (judged by the life expectancy at the time) would recognize you as a European. You would be warmly welcomed and people would ask about your clothes and then you would show them. DO NOT FORGET! THIS WILL COMPLETELY SCREW UP THE UNDERSTANDING OF TIME AND TECHNOLOGY! ]

[Question] [ As a Duke in the Kingdom of Weselton, I've been commanded to exploit the riches of our trade partners and cement our dominant economic status. It was my good fortune to attend the coronation of our most mysterious trade partner Arendelle's new queen. During the after party, newly crowned Queen Elsa revealed she was a sorcerer with the power to create ice, snow, and even frozen lifeforms. Unfortunately, she won't willingly use her powers to fuel my industrial revolution with frozen slave labor. Why she decided to have me and my delegation deported in an abusive manner instead of considering my proposition I'll never understand.... My best scientists and engineers back in Weselton have so far been unable to figure out how we can use her frozen sorcery to our economic advantage. They've talked endlessly of us becoming a chief exporter of ice, but that isn't where the real money is. I want to use her powers to fuel our factories. If she had tropical magic that produced white sand beaches and heat our engineers could harness it in a multitude of ways. Alas that is not the case... Can you help me unlock the secret to harnessing cold as an energy source that my engineers can use to power the factories of Weselton? --- For people unfamiliar with the source material I'm building off of the [Duke of Weselton](http://disney.wikia.com/wiki/Duke_of_Weselton) is a character in the movie [*Frozen*](https://en.wikipedia.org/wiki/Frozen_(2013_film)). [Answer] One option is to use stirling engines. They work just as well on cold as on heat. Or rather, they work on a temperature gradient. [One of these toys](https://rads.stackoverflow.com/amzn/click/B01ABU3Q2M) will work if you place it on a cup of hot water or on an ice cube. You might also look at thermal electric generators, or [TEG](https://rads.stackoverflow.com/amzn/click/B002UQQ3Q2). These create a small amount of electric power from a heat gradient, and so also work with either a heat source or a 'cold source'. [Answer] ## Don't Look for Energy - Go for Infrastructure The problem with freezing powers is that they actively suck energy out of wherever they are used. The movement of the energy itself could be useful, except that it's simply magic'd away to nothingness, which is not very helpful. However, the queen's magic is also capable of very quickly building robust structures (eg. castles in seconds) and fine items (eg. finely tailored dresses) - which are very useful attributes. ## Rapid Prototyping The ability to quickly test ideas to identify what works and what doesn't is a HUGE accelerator for all manners of innovation. 3D printing revolutionized industry for us just a few decades ago; imagine what the world would have been like if it existed hundreds of years ago! Instead of taking dozens of years to refine industrial designs, the Queen could help refine them in DAYS. ## Ice-Dams and Hydro-Power One such use in an industrial revolution is to quickly create very large dams capable of holding vast amounts of water. Such dams could be fitted to power anything from mills to hydroelectric generators, very quickly allowing you to leap ahead technically. Sure, they will need a re-charge every so often, but if you kept a sawmill in operation with the output you could probably cut all the wood you need to replicate it in wood before long. [Answer] You just need to have Elsa turn lots of gas into liquid. The liquid form could be used to power lots of equipment when reverting to gaseous form by expanding through a turbine. What you really would like is a gas that can be freely vented to the atmosphere once it returns to gaseous form. If Elsa could "crank it up" and turn nitrogen into liquid nitrogen, you would have a great power source. Liquid nitrogen requires -196 C -- so this may well be beyond Elsa's power. Perhaps Refrigerant R-12 is a common atmospheric component on your world -- If so, that would work great assuming Elsa can manage -30 C. Perhaps CO2 would work, Elsa would need to be able to generate -79 C, and you need a little extra pressure (5 atm) to keep it as a liquid. If you are a twin of planet Earth, and Elsa does not have much "reserve power", you will probably have not be able to use this option, at least not in this simple form. You could in theory do this trick with lots of other gases, but they would have to be captured and returned to Elsa. Perhaps there is a nice choice that could be easy combined into a compound that could be used. Chlorine seems like a possible choice (although a bit complicated because it is poisonous and corrosive). Chlorine will readily combine with many things and form dense compounds for return shipping to Elsa, where the compound can be split and the chlorine converted back to a liquid. But, instead of a single gas, maybe you could use a combination of Chlorine and Sulfur Dioxide (also toxic). These could be combined to yield Sulfuryl Chloride SO2Cl2 giving you a nice closed loop solution when the liquid SO2Cl2 is returned to Elsa -- allowing pipeline transportation in both directions. [Answer] I'd suggest building nuclear and using elsa to cool the rods and protect your kingdom during meltdowns. You can bypass all sorts of regulations if you have an ice sorceress. [Answer] Elsa is able to move and project her ice, not just create it. This is evidenced in her throwing ice-spikes and the control required to build a castle. Given this there is a very simple option, have her create a giant slab of ice and then rotate it. She can move a turbine by moving her ice, and depending on the upper bounds of her power (which seems pretty high considering the stuff she has shown), she could generate a good amount of electricity just by moving a single turbine. Unfortunately you, good Duke, appear not to have discovered electricity yet, from what I have seen of the recent Documentary Movie about Elsa's coronation. Given this fact, I fear many of the suggestions above are of limited use. Then again, you have somehow discovered computer and internet technology in order to post this question; quite impressive, so you could always try stopping by Wikipedia for the secrets of electricity while you're here ;) Assuming you are not able to steal our secrets of electricity, I fear it's much harder to exploit her gifts, as you lack the automation techniques required to make massive use of anything she does. I will, however, notice that Elsa managed to build things by thinking about them, without a perfect understanding of what she wanted. She likely lacked the architectural knowledge required to build a stable castle, nor the time to fully visualize the castle in her mind during the seconds spent building it. I'm certain she lacked knowledge as to how to create life, this appears to have been accidental. This seems to imply that her powers are in some form imagination based, so long as she can imagine what she wants to create, her powers will figure out how to do it, up to creating life itself. This opens up a far greater use then any infrastructure or power generation option in the realm of research and prototype development. Have her create things that you currently lack the means to generate, and see what happens. Perhaps she can construct devices out of ice which you can then dissect and learn the secret of building on your own, assuming that they function based off of solid physical principles that can be recreated. If they are purely magical constructions, there is still quite a lot of room for her to create objects that can simply not be duplicated by man. For instance, I know Elsa refused to create sentient snowmen for slave labor (what is it with princesses and their insistence on pesky 'morality' anyways!? It's such an inconvenience). However, I believe her complaints were based off of the 'sentience' part. It seems quite likely she could create non-sentient snowmen, without 'thoughts' or 'feelings' or any of that Disney nonsense, just constant moving objects to propel wheels on their own. If my men in charge of understanding 'ethics' are correct this should be morally acceptable to her. Of course why limit ourselves there? Imagine self-propelling ice-ships! Load your cargo on a ship, point it in the correct direction, and tell it to sail to the other continent on it's own. Imagine imagine an auto-sled made out of ice that could be operated by drivers to rapidly travel from place to place! This is just the beginning, with some experimentation an imagination fueled power could no doubt be expanded to generate any number of useful contraptions! I should remind you she also was able to create an infinite flurry of snow to support the entity named Olaf, so she can do the same to ensure that any contraption she generates will last forever without need for maintenance. She can thus mass produce and sell all these magical wonders. Though I must warn you, my Good Duke, that you must convince her to do this of her free will. While no doubt men such as us understand that force is generally a better means of getting lesser creatures to do our will my researchers warn of something the call the "princess effect". Apparently attempts to compel a princess to actions will result in magical resistance, animals will become sapient and serve the princess's will, magical faeries will show up to grant wishes, and of course everyone knows of the pesky meddling of the Princes of the Kingdom Hansom in the affairs of good tyrants (how can one kingdom have so many princes anyways, that king really gets around!). Why just the other week King Horrid of the kingdom Tyrania lost his throne to a princess and her pet baby dragon after trying to force the marriage of the princess of the the lands of Plucky! It may sound horrible, even unnatural, but the one method I know of reported to prevent the Princess Effect is something they call 'caring'. I don't fully understand it myself, but a group of magical multi-colored bears keep telling me about it before threatening to shoot mind control beams at me from the tattoos on their bellies. Anything able to power such mind control powers must be worth harnessing for our own gains! Still, with some wisdom and creativity, I think you should be able to create and sell all manner of magical ice contraptions to the common man. [Answer] well.... <https://www.fanfiction.net/s/10327510/1/A-Bluer-Shade-of-White> there's quite a few ways Elsa "I control more joules than most nuclear weapons" of Arendelle could use her powers productively. As you mention she can produce ice golems which can drive machinery but that doesn't require they be slaves, they can merely be big strong creatures who like walking in big hamster wheels. but that's basic level. She can produce pykrete ships almost for free allowing for easy cheap trade: [](https://i.stack.imgur.com/jdA0T.jpg) She can sell services to hotter kingdoms effectively ending droughts by creating glaciers to provide a steady supply of water to farms. [](https://i.stack.imgur.com/JF2Sk.jpg) For that matter she can create massive damns, basically glaciers deeply rooted to hold inland lakes to drive water wheels. [](https://i.stack.imgur.com/NBFzu.jpg) Her ice is shown to be able to expand and contract pushing soil,earth and rock so she can probably shape large areas of landscape quickly to make way for construction and can definitely create large temporary structures. Add to that she can probably use the ice to create canals and grind stone between ice sheets to create roads. [Answer] Since you may already have a lot of steam engines lying around you might be able to convert some of them to use liquid Nitrogen. Get Queen Elsa to fill some flasks with liquid Nitrogen and then feed it into the steam engine boiler. Allow ambient air temperature to turn the liquid into gas and away you go (zero carbon emissions as well). You might need to have an external heat absorber system (instead of a radiator cooling system) to prevent over cooling. [Answer] You can always a regular steam engine using a fluid which boils at ambient temperature; just build the engine inside a room where Elsa maintains a temperature below the boiling point of the fluid and use the external environment as the heat source. For example, [butane](https://en.wikipedia.org/wiki/Butane) boils at 1 °C; boil it in a boiler outside the cold room (using the heat of the ambient atmosphere) and have the vapor power a regular steam engine *inside* the cold room. In real history, butane was discovered in 1910, but since it's a simple hydrocarbon one can easily imagine it being discovered a little bit earlier, especially given the incentive of making steam engines with the boiler at ambient temperature. [Answer] So you have a person that can create frozen water out of thin air without using up energy effectively giving you an unlimited amount of potential energy. Sounds pretty straight forward to me - forget about using the cold, build some kind of icemill or let it melt and use the big waterfall. [Answer] Unfortunately, [thermodynamics](https://en.wikipedia.org/wiki/Heat_engine#Efficiency) dictate that the maximum efficiency of a heat engine is : 1 - Tcold / Thot Where Tcold and Thot are the temperatures of the cold and hot sources, respectively. Since both are expressed in Kelvins, if we use ice at 0°C (273°K) and ambient air at 25°C (298°K) then the maximum theoretical efficiency is 8.4% which means poor Elsa will have to work a lot for very little energy output. It would be more profitable for her to start an air conditioning business in a hot country, methinks. [Answer] # Gradient and Lack of Friction Engineers can design something around the idea of Hyperloop and really perfect it. * Use this almost fuel-less transportation system for moving goods and people around. * You can have this transportation system installation and maintenance contracts with other kingdoms and build huge business around it. # Ice Castle!! Same as Ice Hyperloops, engineers can build huge ice castles that will melt strategically. These can be big hit in deserts. These castles can provide shelter, source of water. Refrigeration would be bonus (a hole in floor for beer bottle). This is again, never ending contract, benefiting both parties, and no real competition. # It's Not Cold, It's Heat Since cold is not really a thing but just lack of heat, we can assume that Elsa's power is not really to create cold but to manipulate heat. And, once you have control over heat, there are all sorts of ways to fuel Industrial Revolution. [Answer] 1. You could dominate most food trade. You now have capability to refigerate things. Which means a lot of trade goods that were hitherto impossible to transport and store is now possible. This is a huge ecoonomic advantage. She can even make permanent localized effects it seems (snowmans private snowstorm) so they can now sell refigeration units that cost nothing to run. 2. Forget industrial revolution, terraform land. Elsa can capture huge amounts of atmospheric humidity as snow. The sheer amount of snow generated in such short period of time means that Elsa is getting either humidity for free or harvesting it from a huge area possibly from very high up. This means Elsa can turn arid, and desert areas into very habitable places. Even without the snow generation this is potent enough to generate dramatic low pressure areas allowing humidity to flow in aeas where there are none. 3. Winds, elsa can produce gale storm level winds, just slightly more controlled effect and you can power a entire farm of windmills in a way that could do all kind of mechanical work. No steam engine needed even pre industrial tech levels could do this. 4. Elsa can produce heat, why else would the snow and ice melt sonfast once she cancels the spell. Though it is magic so who knows how it works. [Answer] This is a relatively low-tech approach, but I think it is fitting in the universe you have drawn inspiration from: Do recall that Elsa can create animate objects from snow. Just have her create endless rows of ice treadmills and endless snow golems to power each, and voila! Free energy! [Answer] She is perfectly able to create sentient lifeforms. How about sentient factories crawling the forests chopping wood and replanting followed by fast ice carriages taking the wood down to shore. She is capable of doing an industrial revolution on her own since her powers seem to be almost unlimited and perfectly capable of customizing sentient beings. This might also be of interest: <https://www.fanfiction.net/s/10327510/1/A-Bluer-Shade-of-White> [Answer] # Cooling Elsa could provide her sorcery in order to cool down Liquids, like Helium, Methan, Oxygen, ... thus preventing spoilage of such liquids. # Chemical Engineering By providing unlimited freezing power, Elsa could help to engineer new molecules on extrem low temperatures. # Building storage units Elsa could form warehouses which could be used by her lifeforms # Heat Exchanges You could use the same mechanics as fridges, but just vice versa in order to create power. However, this might need some adjustments in physics. [Answer] ## Water Wheels Elsa's power, as shown in the movie, allows her to trigger massive snowfalls, and then subsequently a rapid thaw. When you have a thaw event in the hills and mountains, it causes streams to flow. When you switch back to winter storm mode, that water gets taken back up into the clouds to make more snow that gets dumped back at the top of the mountain. It then flows down the mountain again next time it thaws. It's just like the natural water cycle, only under control, much faster, and without requiring the power of the sun to drive it. It is effectively a perpetual motion machine. A never-ending flow of water running downhill. Once you have her under your control, all you have to do is build lots of water wheels to harness the energy, and you'll be unstoppable. [Answer] See if she can create non sentient moving objects. If she can create a rod that spins within a stationary collar, you can power just about any industrial bit of machinery. Mount the collar on something that doesn't move and then mount something (like a mill or anything else) to the rotating rod. By using clutches and gearing you can start, stop and modify torc and speed. You could even make rudimentary automobiles by having the wheels clutch onto at rotating axle. [Answer] Cooling is just pushing heat somewhere else. Since Elsa can cool anything at near instant speeds it stands to reason that she can freely control energy. Look up some scientific break downs of how iceman's powers would work IRL. Essentially, you have access to nearly infinite energy all the time anytime because you can push the heat, out of pretty much everything. All you have to do is engineer things to organize the random movement that makes up heat to do work and you're set. [Answer] # Elsa Lies: Conservation of Energy Means She Has Heat Too The first law of thermodynamics says that energy must be conserved. If Elsa is creating ice castles, she must be holding on to the heat somewhere. Because Elsa must be lying, she is hiding something from you, and you cannot trust her. I would not assume you could harness her cold energy at all. But she did invite your delegation to a meeting, meaning she is interested in something about you. Perhaps she seeks to destroy you, and she knows granting you her powers will destroy you, much like colonists did with opium. Or perhaps, she is simply bartering her cheap powers for something more valuable, much like the smae colonists traded guns and horses for land. # She Wants Something Else So given that she is lying, and that she harnesses such immense power, the only reason she is speaking with you is because she must want something else. Unlikely that it'll be anything materialistic, with her power she could easily obtain anything that can be made. More likely, Elsa wants something more ephemeral, perhaps respect, friendship, or even love. Figure out what she wants, and you will have your power over her. Attempt to engineer her powers to your will, and you can only bring yourself ruin. ]

[Question] [ Joe has a slightly embarrassing issue. Simply put: Everything he says is true from that moment on until Joe himself contradicts it. For example: If Joe were to say that hundreds of people turned up at his birthday party the very fabric of reality would be altered such that, for whatever reason, hundreds of people turned up at Joe's birthday party. This includes editing the past, altering the weather, and manipulating otherwise random events all the way back to the big bang. Joe can't affect the fundamental truthiness of his statements, and blatant logical or linguistic paradoxes like 'This sentence is a lie' will either do nothing or randomly flip to one of the potential outcomes. If Joe says something that is physically and universally impossible (for example: 'Pi is exactly equal to 3.14') then nothing happens, but if there is the slightest chance (however improbable) that it may occur then Joe can make it so it did. Joe is allowed to make temporally paradoxical statements, with the caveat that the universe will preserve his own existence and ability to make statements at all costs. Statements like 'My biological father died before I was conceived' will somehow work themselves out such that they are then true (potentially a sperm donor, or alien clones). Statements like 'I'm a unicorn' will result in Joe being a sentient unicorn capable of talking, all the way down to potentially rewriting the entire evolutionary history of Joe. Intent means a lot when he makes statements, and in many cases the things he says are subconsciously caveated with 'but other things stay pretty much the same'. Joe has grown up with this power. To him it is entirely natural. Needless to say he is not the most balanced of individuals and will happily blot entire worlds out of existence without thinking anything of it. The question is whether it is possible for anybody to notice what Joe is doing, given that the entirety of history will (and in some cases must) be rewritten for Joe's statements to become true. Taking the unicorn statement as an example, is there any way for people to realise that Joe has rewritten the universe such that he is a unicorn, rather than them just accepting that Joe is a unicorn (or possibly being weirded out by the unicorn that's saying it's called Joe)? **Edit for clarity:** Can't believe I forgot to mention this: Joe's memory is inviolate. It's one of the things maintained, along with Joe's ability to make world changing statements. **Edit II:** Joe is, in this case, being used as a proxy for various potentially world changing entities in this world. **Edit III:** yes, other peoples memories are edited as a natural consequence of the world being different. If they weren't this would be a very simple question to answer. :D [Answer] Yes. Very easily, depending on what Joe wants to change. Edit: additional assumptions. 1) the universe takes the path of least resistance to validate his statements. Therefore, rewriting the past is only done when no other solution is present. Occam's Razor almost. 2) Joe has not explicitly stated that no one will notice this ability. Otherwise this post would be a moot point. If Joe decides to predict/alter the future, it doesn't affect people's memory, and can become suspect. Imagine if Joe is growing up and gets excited for Christmas, as many young children do. Imagine Joe says "Santa is coming! Santa will come down the chimney tonight and bring me presents!" Then imagine how the parents may react when a fat, red-suited, jolly man actually does come down the chimney at night and leaves presents. It shouldn't be hard for him to simply say something that is unlikely and have it happen. He could predict the next election 10 years in advanced, predict any sports game upset, or predict the winning lottery numbers for a week in a row just by saying so. If any of my friends did that, I would notice pretty fast. So long as he doesn't limit himself to just altering the past, people will notice. He may make them forget, but someone at some point will notice this gift, at least for some time. [Answer] I would say it is highly unlikely for people to discover his ability. If he states that he is a unicorn, he doesn't just turn into a unicorn. Based on your description, it would go back in time, and rewrite history so that he is born a unicorn and now is a present day adult unicorn. So anyone that would know him from the past would know him as a talking unicorn. The only way really for someone to know he is with such power, is to observe him saying something and then it happens in front of them. But even still, it seems like his power has the ability to erase from existence. So if he says that tree right there will disappear, it will vanish and it's existence will have been deleted to the point that there is no record memory of it. The person observing this would turn to him and say there is no tree there what are you talking about? You have pretty much given this guy the power to alter everything. Everything he changes would in turn alter everyone's memories unless I am slightly miss understanding something and people retain their memories of what use to be vs what is now. Then yes, it could be very easy to observe him walking around changing things as he pleases. Everything around him would be constantly modified as he interacts and would be very noticeable to the observer. So kind of depends on how much power his statements have and where you want to go with it. [Answer] It depends what Joe wants. It is entirely possible that people might notice that something is going on - although depending on the exact mechanism it might be very hard to notice; but if Joe doesn't want anyone to notice then of course he can instantly make *that* true and it immediately goes away. [Answer] Joe isn't changing anything, although he thinks he is. What's actually happening is that he is somehow able to move freely between every alternative world in which a Joe exists. The Everett-Wheeler multiple worlds hypothesis is true with a vengeance, and there is an infinity of worlds larger than even God can imagine (literally: Joe says "God does not exist", and is in a world where God doesn't exist). This explains why he cannot create the mathematically impossible or the physically paradoxical. Worlds such as these have a mathematical probability of zero, so they do not exist and Joe cannot move into one of them. Presumably there is some sort of Hilbert-hotel permutation of alternative Joes, which is why he never finds himself face to face with himself, and we never notice any paradoxes. (Alternatively, Cantor dust; the infinity of Joe-containing worlds is a smaller infinity than the totality of worlds). Any mathematicians reading this are advised not to think about it too deeply, because contemplating infinities stacked upon infinities is well-known to be deleterious to one's health. Joe is blissfully ignorant of mathematics beyond his times tables. We might speculate on what his fate might be, if ever "infinity" came to mean more to him than "a very big number". [Answer] His power only means that his statements are true, not that people won't be suspicious. If he says something along the lines of "From tommorow on I will be a unicorn and everything else will stay the same" people will remember him being a normal human, when the unicorn starts talking. For the universe it's enough to send a crazy bio-engineer along and transform him into a unicorn over night. No need to change anything else like the memories of his friends or evolution, so why should reality do it? **Just let the universe take the line of least resistance.** [Answer] # **The universe is smoke and mist to Joe** I don't think Joe is going to stand out too much all of the time while at others it will seem obvious but it's all irrelevant to Joe. **Fluid universe around Joe** The entire universe can casually rearrange itself entirely around him. One day a careless statement leaves him in a sci-fi universe with hyper-advanced AI who have spotted that everything he's ever said appears to be 100% true. In the next moment after a casual utterance ,perhaps about dinner tonight, that reality is unmade entirely and the entire history of the universe has placed Joe in a medieval village. Joe will be protected no matter what, any attempt by a nutjob to kill him or an AI overlord to hotwire his brain will fail because reality itself warps to protect him. Unicorn Joe won't seem weird because Joe will always have been a Unicorn or there will be a clear path of events that led to Joe getting a unicorn body. **Exceptions** Joe utters the words "your memory and existence will be inviolate like my own" to someone. Perhaps a romantic interest, perhaps someone he simply grabbed onto in the forever shifting churn around him. Suddenly there is someone who can remember that yesterday Joe was not a unicorn. Suddenly there is someone who can see the weird stuff happening. Joe can revoke that if he really wants to but perhaps he doesn't. **If Joe is a human... then Joe is going to be a very weird person.** *If Joe is a human then Joe was once a toddler going through the terrible 2's.* Imagine the world view of a child who takes it for granted that anything they say out loud is true. Nobody can ever have made this toddler go to bed if they didn't want to. Nobody could ever have made them do anything because they could just scream "I'm NOT going to bed!" This is an entity which had every wish granted from the moment it could speak and never had to fear anything. The suffering of people around it are as irrelevant to it as shapes in the mist. The people around it shifting as ephemerally as that mist. [Answer] Assuming Joe doesn't actively negate the possibility "No one has discovered my power", then people will begin to notice that at the very least Joe's memory is unnaturally accurate. This could get even more interesting with sequences like: ``` Person: I like that the moon is a nice shade of yellow. Joe: The moon is green! Person: Uh, I know. Why are you telling me the obvious again? ``` The person's memory would have been rewritten to know the obvious thing that Joe had just changed, but you'd assume they would still have heard Joe's statement on the fact so Joe would be seen as they type of guy who always states the obvious. Things could easily get weird from there, especially with statements like: ``` Person: I think you have some sort of odd powers. Joe: You've never noticed anything odd about me. Person: You're right, but now that you mention it, I think you have some odd powers. Joe: No, you don't think that. Person: I don't think what? Uh... What were we talking about again? ``` Joe would have to be very, very careful. In fact, just not talking until he'd really thought something through would be safest. [Answer] Depends a lot in what he says. Some things are impossible to suspects. But there are others things can make people doubt him. For example, he says: * "This year i've made 4 phd careers at the same time. One of them in USA, another in Australia, other in Japan and the last one in Brazil. And of course i've continued being the president of Mexico, and i reached the rank 1 in Tennis and made my Rugby team the world champion." and more things. Maybe it's likely impossible, but if it's true, people would suspect anyway. * "God talked only to me, and he said 'Joe, take only 2 criatures for each animal species and make a big ark because i will die tomorrow and that's my last wish. And don't tell anyone'", if Joe made all people to notice he isn't crazy, lot of people would be like, "¿Why God will talk only to you?", and of course, anyone can think whatever they want, including suspect him. * "Tomorrow would be 3 earthquakes and Nigeria will eliminate Germany on Soccer by twenty three goals", and lot of predictions, as stated by ChronoD * "You are thinking in a 3, and now in a 7, and now in -67.840002, and now in Game of Thrones", if he say that to a lot of people (Worst if he say that to all of them at the same time), there will be somebody who cant doubt him? * "You will never forget me" and some similar ones. He could break his own powers if he isn't carefull. * "Hey chief! I've made all of these company work by myself. Anyone made nothing. Only me", there are people who can't be lazy, and can't accept that fact. Even, could doubt from other people but not in himself.... Crazyness would arise as side effect too. The same applies for calling people liers and other things that people care a lot for themselves. And probably lot of examples like those. However, all suspects can be cleaned by his magical words if he want. And hide all clue. [Answer] **Joe would appear to be psychic / prescient / omniscient**. He would make statements about things he couldn't possibly know about, and the cosmos would conform to make the statements true. As a trivial example, Joe could enter a standard ESP test and correctly guess fifty out of fifty randomly-drawn cards. Your description tells us Joe can't even sabotage his own efforts by stating something impossible or improbable -- if he intentionally guessed "ace of spades" when guessing Monopoly properties, he cosmos would retroactively add an "ace of spades" space on the board, or the experimenter would have added "ace of spaces" as bad data to test Joe's psychic powers, and then Joe guesses correctly. Nobody affected by Joe would know that things had changed, because to them nothing has changed. This brings up an important side-effect: **Joe would appear to have dementia**, because his memory is not changed by his cosmos-altering power, so Joe's memory would disagree with everyone else's. This would appear to any (every!) observer as hallucinations or psychosis. He might ~~claim~~ act as if humans didn't have five fingers to each hand until a few minutes ago, even if that was always the case. EDIT: wizzwizz4 correctly points out that anything Joe "claims" will be true. Instead, Joe would do inexplicable acts like trying to pick up an item with his second thumb, writing a cheque using base-12, or buying hats in pairs despite having only one head. If he fails to explain why (especially if he isn't aware of witnesses), he will appear to be acting nonsensical. Joe would appear to be both gifted and ill, remarkable and pitiable. We would never know Joe alters the past because the past is the only thing we have to measure with. [Answer] They will notice if Joe wants them to and not if Joe doesn't want them to. All it takes is one sentence from Joe "Everyone on Earth is always oblivious to my powers." and so shall it be. If Joe were to say "There must be someone who noticed my powers." then that will also become true. If this is for the plot, then all you need to do is either make Joe paranoid about his powers and mutter the second sentence to himself or make him abuse his power to make everyone not notice it. [Answer] Maybe nothing special would happen and Joe would came unnoticed as really quiet and good person :) As @Murphy stated: *If Joe is a human then Joe was once a toddler going through the terrible 2's. Imagine the world view of a child who takes it for granted that anything they say out loud is true. Nobody can ever have made this toddler go to bed if they didn't want to. Nobody could ever have made them do anything because they could just scream "I'm NOT going to bed!"* It is perfect time for lazy universe - Joe is not aware about world much and mainly talk about himself and his close family. And does not want nothing much complicated and elaborated - "I'm NOT going to bed!" "I'm NOT eating that!" ... the easiest way is, that he's just NOT going to bed and eating that just now and nobody is able to force him. But his family knows at the point, that something is wrong with Joe, as other childs are pushed to bed and fed with that usually anyway. And it would not be long before somebody tell something like "I cannot put eyes from you, cause you will make some problems again ..." and Joe scream "I'm NOT doing any problems again" and that is true. From that moment Joe is unproblematic child, does not scream statements that change things, usually does not talk much and when he talks, it is polite, like "I would rather not eat that" (and it is true, he really would not like eating that) but when mother say "But eat it anyway" he would do so (to not make problems again) even if he really hates the food at the moment. And lazy universe have spare itself a lot of changing. Joe will grow quietly, until he get much better grasp of the wolrd around and himself and found out, that he actually have power to change things, but only if it does not "make problems again". So he have to learn how to formulate his wishes to not make problems and the world slowly turns to really nice place. Some agencies will find eventually, that he have real power, but when they try to missuse him, he reflexively turns them away to "not make problems again" in very subtle and sophisticated ways. Common people would not realize him as the source of changes, as he prevents it too, but this does not prevent them from feeling good around him while talking about their problems and those problems somehow sorts out itself in some time, in visibly only natural ways (drunken sailor is moved by tears of his wife, as he still love her and stop drinkig too much, then he drinks only ocassionally and a little, while his wife appreciate that and stop yelling on him and cook for him every day, becoming good cook and even starting famous home restaurant so they no longer suffer from powerty. And it is all done by power of love and hard work, no visible magic ...). :) [Answer] That is a pretty unstable power **sure everyone will notice something wrong is happening**, you should treath what Joe says as Wishes, assume Joe enter in a Bar and says: > > The barman offer a beer to Joe. > > > In the meanwhile in the whole world **every person whose name is Joe is offered a beer by a random barman**, even if those Joes are not in a bar. A barman was left frozing to death when he suddendly appeared on Mt. Everest while a climber named "Joe Sullivan" was resting on a small platform he saw a barman appearing and offering him a beer, immediatly after the barman realized he would have froze to death. The fact that truth is really a dangerous practice. Joe is likely will quickly learn to speak in the most possible and precise way, or to possibly don't speak at all, or to speak only through making questions and by never telling something as a affermation. It could also lead to an orc Paradox. What if joe says: > > If I'm true there's a mountain over there, If I'm wrong there's a sea over there, and I'm wrong. > > > ? Joe is wrong, then a sea should appear. But then Joe would have been correct, and hence there would be a mountain, but in that case Joe would be wrong. [Answer] The potentially world changing entities, of course, will notice. Either in their own right or through the agency of observers acting as their proxies. They have the chance to make the statement: "Joe will never know or be aware we exist. If Joe even suspects we exist, that thought will be immediately blotted from his mind, leaving no trace in his memory. Nothing Joe changes will change or affect us and our observers. Joe will never say anything to affect or change us." This safeguards the other world changing entities. Now they might decide to set up a control to Joe's world changing activities. This can be any ordinary person like Fred or Marge whose memories will be engineered by the other world changing entities to be unaffected by Joe's world changing statements. The only other way has already been proposed by Matt Bowyer and would have been by Erik (if Matt hadn't struck first). Namely, that Joe himself nominates someone to remember despite his changes. Thanks, guys, for beating me to this solution too. There was one other faint possibility worth considering. That, irrespective of what Joe says, the world changes require his intention about what changes. There could be things and people who exist in our world about which or whom Joe is unaware. If so, when the world changes including its past these people and things remain unchanged. For example, a Mongolian taxi driver with a PhD in nanotechnology (a category of person Joe had no inkling existed and therefore wasn't changed by Joe's latest edict) might wake up to discover Joe was now president of the USA when yesterday it had been Bernie Sanders. If the world changes were mediated by 'something' that had to interpret his words about what world change he wanted, and possibly had to reconcile this with his intentions. There is the possibility that some persons or things will be left behind unchanged. perhaps over time as more and more the world is transformed by Joe less and less will remain behind unchanged. In which case, during the early phases of Joe's world changing he might be confronted by Mongolian taxi drivers waving their nanotechnology PhD degrees in his face and demanding to know why the world keeps changing. "Don't worry," said Joe. "I'll soon fix it." [Answer] The most important part to me comes in you second edit: > > Edit II: Joe is, in this case, being used as a proxy for various potentially world changing entities in this world. > > > So what does your universe do, if Joe1 says, that earth do not have (and never had) three moons, while Joe2 is visiting all of them by his special power? Well you gave kind of an answer for this: > > Joe can't affect the fundamental truthiness of his statements, and blatant logical or linguistic paradoxes like 'This sentence is a lie' will either do nothing or randomly flip to one of the potential outcomes. > > > If that happens in that case, people will notice something odd, because the universe created by Joe1 does not take into account the changes of Joe2. These changes have a chance to happen randomly, instead of Joe1 changes, which will create unfitting situations. If you now come to the point, that only changes happen, when they do not contradict the changes of other "Joe", you would limit the abilities of these entities by several magnitudes, and create the necessity for this "magic power" to know every statement which any Joe would ever make to check for inconsistencies. [Answer] Joe says, “you beleive me, right?” or “nobody ever discovered my secret power.”. So it’s up to him. No other reasoning is possible for this answer, since Joe can always override the probable with his statements. [Answer] Every time Joe says anything, it effectively leads to creation of alternative reality that lives according to Joe's wishes. If there are no traces of previous reality left (except perhaps in Joe's memory), then the answer is no - people can not notice that Joe has this kind of power. Nobody would have any knowledge of previous reality that existed before Joe said his last sentence. I would, however be very careful if I were Joe. Some innocent phrases like "It's a slow day today" have potential of ending the universe as we know it. [Answer] There are several ways a person who Joe has not explicitly made aware of the situation can become aware of it, so long as Joe does not prevent this from happening. Some of Joe's comments may require others to observe changes in the universe rather than have it appear to always have been so: > > "There was a park here a minute ago, but now it's an airport." > > > Because for the statement to be true, an observer would have to know that the previous state was true, and would surely remember it. Memory alteration would cause the statement to be false for that person. --- If Joe's comments are not contradictory of present reality, no rewriting will take place and his ability to state what will happen would be deducable due to probability. > > "I'm going to get four straight flushes in a row! > > > "That dog is going to jump over the car, land in a roll, and come up doing a moonwalk while singing showtunes!" > > > "Everyone who sees this answer is going to upvote it!" > > > On seeing anything incredible happen right after he said it, it would immediately draw attention to how unbelievably coincidental it was. At first it would appear to be predictive rather than causative, but that could eventually be figured out. Even mundane comments about future events will tip people off that Joe has an uncanny ability to state what's going to happen. One or two comments would not be surprising, but if everything he said always turned out to be true that would be enough for people around Bob to become curious and eventually discover his ability. [Answer] This whole situation depends, for obvious reasons, on when the universe decides that his statement is over. For instance, let's suppose that Joe states, "I want to be a..." and before he can finish, he is turned into the letter A. Maybe the universe waits for him to pause a certain amount of time, as if he has finished his sentence? Maybe he simply states a keyword as a method of ending? Obviously, this is an important bug/feature (depending) of his power. As an add-on to the previous paragraph, this power would also depend on the level of ambiguity of Joe's statements. If Joe stated, "I am a vehicle," then Joe may be any random vehicle, even those not invented yet, depending on the universe's definition of vehicle. Joe may wish to learn a different language using more precise nouns and adjectives, or he may simply state that he has already invented such a language and use that instead. I don't think people would notice, given this situation, though, because that's the way things have always been. If somebody else had the power that their memory was also inviolable, then he could say that he/she has never existed, and then that person no longer exists. [Answer] His teachers would notice, due to his getting 100% on every test. Or, at least, every test where random answers don't affect fundamental physics. In a maths test, if he answers "What is 1+2?" as "4", then either he'll get it wrong (can't change fundamental physics) or the symbols "3" and "4" will switch. If it's the former, maybe he won't get 100% in maths. But, in something like a history test, with questions like "Which Prime Minister took Britain into the second world war?", if he answers "Tom Marvolo Riddle" then Neville Chamberlain will always have been called Tom Marvolo Riddle. ]

[Question] [ While doing research, I stumbled across the alloy "[arsenical bronze](https://en.wikipedia.org/wiki/Arsenical_bronze)", in which copper is smelted with arsenic instead of (or in addition to) tin. This apparently gives you "a stronger final product and better casting behaviour" than ordinary bronze, but what interests me is the use of a toxic metal in an alloy that was used, among other things, to forge swords and axes. Arsenical bronze doesn't have enough arsenic in it to be toxic, but it got me thinking. Poisoned swords/knives are common enough in medieval fantasy stories, but you'd have to keep applying the poison to them, and that's a pain. But what if, by using [toxic heavy metals](https://en.wikipedia.org/wiki/Toxic_heavy_metal) or their various alloys, you could forge a sword that is *naturally* toxic? In other words, **is it possible to create a sword with the following properties:** * Can be forged using medieval technology * Has a blade at least 45cm (18in) long * Is durable enough to survive a swordfight without breaking * Is toxic enough that being cut by it will cause some kind of physiological damage. It doesn't have to be *lethal*, but it should be more harmful than just being cut by a regular weapon * *Ideally* does not slowly poison the wielder, so long as they refrain from touching the blade Things I am willing to handwave or ignore: * Whether the necessary elements/alloys, or their toxic properties, were known or readily available in medieval times * Whether the person who forged the weapon would have been poisoned in the process --- Since a few people have asked what the use case for this weapon is: I was thinking it would make a cool unique weapon for my RPG series (hence the "medieval" requirement). A toxic sword isn't particularly useful in a real swordfight, but in an RPG battle where powerful enemies could tank dozens or even hundreds of hits, suddenly it's a lot more handy. --- I am aware of [this similar question](https://worldbuilding.stackexchange.com/questions/99646/can-arsenic-make-deadly-weapons), but it's specifically asking whether you could use pure arsenic to make a toxic sword, and the answer is no (it's too brittle). I'm asking whether there are *any* alloys that would let you make such a weapon. [Answer] There's a lot of toxic metals. Most are toxic in fact (including iron technically, if you get enough of it). Almost all of them have issues though: * Mercury: One of the first metals many people think of when they are thinking of poisons. The problem here is quite simply that even those mercury alloys that are solid at room temperature (known as amalgams) are generally not hugely toxic (they were even used classically for dental fillings). In fact, most of the mercury compounds that are toxic are entirely non-metallic (see dimethylmercury for a particularly nasty example), and therefore not very good for swords. The fumes from mercury are, however, rather toxic (they're a slow acting neurotoxin), so maybe you could coat your weapon in mercury (though that would put you at risk too). * Lead: Is a very slow acting toxin, and does not lend itself well to usage for a sword. It's also not very readily absorbed by the body in pure form, with most of the toxic forms being salts (white lead for example) or organic compounds (like tetraethyllead). It's also not good for a sword, it's way too soft, and it tends to soften other alloys (steel with a high lead content has a significantly lower shear strength than steel without much lead in it). * Cadmium: Is also mostly a slow acting toxin. Most of the same issues that lead has for this usage are also problems with cadmium. The biggest difference is that it would be a whole lot more dangerous to the swordsmith to make a sword out of cadmium, because the fumes and dust are far more dangerous than those of lead. Interestingly, cadmium is rather corrosion resistant, so if you were to go with this, the sword would actually not need to be cleaned as thoroughly to keep it in good condition. * Thallium: Most people probably haven't heard of thallium outside of chemistry class as it's not used for much. It's located right between lead and mercury on the periodic table and is actually significantly more toxic than either. It's interestingly one of the few metals which are actually sufficiently toxic in pure form to be dangerous to handle and *might* work here. Unfortunately, it's not very practical for this because the swordsmith would most likely receive a lethal dose well before he finished forging the sword, and it's also very soft and has a low melting point (just like lead), which means that alloys incorporating behave similarly to those which incorporate lead. Somewhat notably, thallium and its salts were a favorite means of political assassination in ancient Rome. * Osmium: Like thallium, most people won't have heard of this one much outside of chemistry class. Osmium might be the closest to what you're looking for. It naturally oxidizes in air to form osmium (VIII) oxide, which is insanely toxic (concentrations so small you can't tell it's there can cause pulmonary edema and permanent blindness) and also sublimes readily (converts from a solid to a gas). Osmium is also the densest naturally occurring chemical element known to man, so anything made of it is *heavy* (good for a weapon if used right), and it's also rather durable too (it's used in small amounts in alloys for fountain pen nibs for this reason). The big issues here are that just like thallium, it's liable to kill the swordsmith well before he finishes the weapon, and, more importantly, the weapon would just as dangerous to the one wielding it as the intended target (because of the fumes). Also, since the amount of Osmium refined yearly would fit in the palm of your hand, it would take a while to save up for and to accumulate a sword-sized chunk of it. (It isn't near as expensive as, say, Rhodium by a factor of ten only because the demand is way lower.) Only one commercial object has ever been crafted of near-pure (0.9995) Osmium: some 1x1cm polished cubes of Osmium made for Luceteria Science by a lab in Beijing for "element collectors" with "Periodic Table Displays". This is the only lab with any experience at all in working and finishing the pure, almost unworkable, Osmium: good luck forging a blade out of it.] * Chromium and vanadium: Both of these are probably already in your steel in small amounts. Both of them have a number of compounds that are very toxic (vanadium more than chromium). Unfortunately, none of these compounds can be produced in a weapon (they're all salts in some way) in any way that wouldn't make the weapon significantly less useful (they would compromise the structural integrity of the weapon). * Nickel, copper, cobalt, silver, scandium, and yttrium: Similar story to chromium and vanadium, just not likely to be in your steel already. * Zinc: Zinc is actually an essential nutrient. Like most metals which are essential nutrients, getting too much is very bad for you. Overabundance of zinc in the body causes all kinds of nasty things, interfering with copper and iron uptake, destabilizing cholesterol levels, and acting as a mild neurotoxin with permanent effects. The problem with using it for something like this is that it's the ionic form, not the metallic form, that causes problems and is readily absorbed. In fact, most of its alloys that are actually practical for swords are pretty much entirely non-toxic. A pure zinc stiletto might be viable for this if you stab someone in the stomach (such that it ruptures the stomach), because stomach acid dissolves zinc, and the resultant zinc chloride solution is really corrosive, but such a weapon would effectively be a single-use affair. * Antimony and arsenic: Not technically metals, though they are found in measurable concentrations in many old steel alloys. Both of these are reasonably fast-acting toxins in their oxide forms and oxidize readily. However, proportionate to how much you can reasonably put in a sword the size you're describing without making the steel useless for a sword, it takes *a lot* to actually kill someone. They are however persistent toxins (that is, if you get a bit of arsenic or antimony oxide in your body, it's going to stick around for a long time), and do have effects prior to reaching lethal levels (they make the victim tired, because they interfere with energy storage in their cells). * Selenium and tellurium: Similar story to antimony and arsenic, except these generally aren't found in even the oldest steels, and the mechanism of toxicity is somewhat different. * Aluminium: Believe it or not, aluminum is actually toxic to most living things. It's unfortunately impractical for what you want for a lot of the same reasons that aluminum foil doesn't poison people, it forms inert compounds very readily (aluminum oxide is non-toxic and extremely unreactive, and forms readily in air), the metal itself isn't well absorbed by the body, and rather large amounts are needed to cause significant effects. * Beryllium: First off, beryllium is impractical for a sword, it's too light and brittle. There are some other issues with using it for this though, most notably that it's not really all that toxic in its pure form (you should be noticing a theme here by now) or when alloyed (beryllium copper is a good example of an alloy that might work for a sword, but it's generally considered perfectly safe), with the compounds being the biggest issue (except see below). It's also not easy to alloy with most metals, difficult to work, and, most interestingly, is primarily an issue in the form of dust (which has similar long-term effects on your lungs to asbestos). * Lithium: Lithium has similar issues to beryllium, but deserves separate mention form the other alkali metals because it also has some of the same issues that aluminum does (namely, it readily forms inert compounds). * Rubidium and cesium: Both of these are really nasty slow acting toxins if ingested in the form of water soluble salts (for example, chloride or nitrate salts) because the ions interfere with biological processes that normally use sodium or potassium ions. Both of them are really nasty explosives if exposed to air (they react with the moisture in the air just like potassium and sodium react with liquid water, just way more so). THey're also damn near impossible to isolate in their pure form by any means other than modern technology. Given these constraints, they're impractical for what you want. * Strontium and barium: Same issues as rubidium and cesium, except they're not really explosive in air. * Lanthanide metals: All of these are toxic to some slight degree. They also have physical properties that make them unsuitable for use as a blade and are insanely difficult to isolate (to the point that many of them were not isolated in their pure form until the later half of the 20th century). * Radium, uranium, and other radioactive metals: All radioactive, so they violate the requirement that it does not harm the user. Also, actual toxicity other than the radioactivity is not well characterized. * Polonium: Polonium is insanely radioactive. So much so that less than one *microgram* (one *millionth* of a gram, that's about 1/60th of the size of a grain of table salt) is enough to kill someone due to acute radiation poisoning. Handling it is dangerous to the point of being almost suicidal. It's also really rare and extremely unstable, so the likelihood of getting enough to do anything practical with in medieval times is essentially nil. Given all this, while it would be very effective, it's also highly impractical. I've mentioned it here separately from the other radioactive metals simply because it's so much more dangerous. I've refrained from mentioning many of the transition metals above, as they're either not reactive enough to be meaningfully toxic (titanium, platinum, palladium and iridium), too hard to isolate or reasonably work with in medieval times (tantalum, hafnium, niobium, manganese, tungsten and all the ones whose name begins with 'R'), or are just plain impractical for a sword. So, overall, you're not likely to find a metal that can do what you want just based on metal alloys. There is also the issue of exposure. Cutting someone does not allow for much exposure, because the blade is kind of supposed to remain in one piece without losing much (if any) mass. Even regular blades coated in poison are not particularly reliable in real life, as reliable delivery of the poison is still difficult even if it's a liquid. [Answer] In order for a poison to be effective, it has to be transferred into the target. If the source of toxicity is the metal itself, the sword could only work if with every blow you'd be leaving enough of the blade in the wound to deal meaningful damage. That's even worse than dipping the blade in liquid poison before battle. Instead of running out of poison and being left with a regular blade, you'd run out of the poison AND the blade, being left with a subpar weapon. On the other hand, as M. A. Golding said, a disposable blade like an arrow or javelin tip could be an application for a toxic metal. Unfortunately, for a something solid to be readily toxic, it has to react with blood, and if it does that it'll most likely react with air moisture over time, so your arrow tips would decay in storage. Still, not an improvement over surface-applied poison. The problem with using metals as poisons to get them into the victim's body. Not just get inside physically, but biochemically. Gold here is an outstanding example: gold, in fact, is as toxic as you'd expect from a heavy metal. But it's so unreactive in metallic form that its bioavailability is pretty much zero. But gold salts (actual salts, like gold chloride) are dangerous. Similar (but less shocking) thing is with mercury. How toxic is a drop of mercury once in a lifetime? Hardly. You can play with it with your hands. You can swallow it and you'll crap it out. You can inject it and the worst it can do is mechanical vein blockage. Metallic, it doesn't enter your biochemistry fast enough to be deadly on exposure as short as you have in battle. Only after years of prolonged exposure you can get [mad as a hatter](https://en.wikipedia.org/wiki/Mad_as_a_hatter). Compare that to [dimethylmercury](https://en.wikipedia.org/wiki/Dimethylmercury) (organic salt): a single drop on a rubber glove clad hand and it's [lethal exposure](https://en.wikipedia.org/wiki/Karen_Wetterhahn). "One of the strongest known neurotoxins." Bottom line: toxic metal in a sword is dangerous only to the soldier carrying it. Just like any toxic solid. [Answer] You don't need any special materials to make a toxic sword. If you want a sword to be useful for as long as possible, you will make it out of an alloy that is resistant to oxidation. Oiling it here and there and keeping it in its scabbard go a long way into keeping the sword from rusting. Now sometimes you have a bastard sword, and sometimes you have a bastard swordsman. If you don't take good care of a sword - or if it is just too old - the sword will become rusty. Much worse is someone who would be negligent on blade maintainance on purpose. Anyone who is cut or maybe even just scratched by such a blade will need a shot for lockjaw, a.k.a. tetanus. The rust itself does not cause the disease, but the bacteria that causes it loves rust. Now remember, vaccines and antibiotics were invented way after medieval times. I've heard historians say that anyone that survived a battle in ancient and medieval times would likely die or lose a limb due to infections (not only tetanus). Cutting a fellow soldier's arm and cauterizing the wound with red-hot iron was a thing in some places. So there... In ancient times all swords were toxic, but not in the way you probably were thinking. [Answer] The metals which are pretty nasty when present into wounds do not suit well for making a blade: alkaline metals like sodium can be really dangerous when in contact with water-based solutions, causing burns, but they are pretty soft. The closest you can get is having a bladed with a rough surface (aside from the cutting edge), where you spread quicklime (CaO) before each battle. Being highly reactive with water, quicklime would have a nasty effect when dispersed into the wound upon cutting the flesh of the victim. When the blades clash during the battle would disperse powder of quicklime, which upon landing on the sweaty skin of unprotected fighters could also cause burns or irritation. But then your fighters cannot fight a la 300. Quicklime was commonly used for building in middle age, and its reactivity with water was known. [Answer] According to at least [one science fiction authoring team](https://en.wikipedia.org/wiki/Riptide_(novel)), iron from meteors may possibly be radioactive enough to cause physical damage to people who touch it, but if it is, that damage would still be rather slow. So radioactivity is better reserved for justifying curses than powering death blades. Also, short of lead-lined armor, radioactive blades tend to hurt their wielders more than those they are wielded against. Bacteria would be my go-to for creating a kill blade. With little more than a layman's understanding of modern germ theory, a warrior could brew up something really nasty using the dead bodies of his previous victims, then carefully contaminate the cutting edge of his swords. Again, death wouldn't be instantaneous, but in a medieval age, it would likely be guaranteed. Alternatively, a skilled iron-smith could carve ridges into the blade's plains along the surfaces which will contact enemy flesh after the cutting edge has done its job. In those ridges, any number of fast-acting poisons, narcotics or psychedelic compounds can be stored. [Answer] **I don't think so,** So far, the answers all focus on additives to a standard sword (poisons, additional toxic metals that have to be added or replaced to keep the sword toxic. *Metal Sword* Your question seems to be asking, though, if a sword in and of itself can be a toxic weapon, without having to make and add poisons or heavy metals. Metals that are good for making swords (bronze & iron) aren't in and of themselves toxic; toxic metals known in medieval times (mercury, arsenic, lead) aren't really toxic enough immediately after battle for them to help much. Possibly if you were able to stab someone sixty or seventy days in a row with a lead sword, some bits might get lodged in his body and cause lead poisoning... Not very practical! *Stone & Wood Swords* Useful toxicity is a strong province of biological agents. Some woods can cause reactions, but really aren't strongly toxic enough in and of themselves to be the weapon you're looking for. Perhaps if you made a sword from fresh [manchineel](https://www.sciencealert.com/do-not-stand-under-world-s-most-dangerous-tree-manchineel-tree) wood. The sap is extremely toxic. Stone is not terribly toxic either, though compounds that are (lead or arsenic compounds) don't make for very sturdy swords! [Answer] It's not realistic as poison *in general* is not very realistic for being useful on a sword. Poison ist for maliciously, and covertly, murdering someone. It's not what you bring to a sword fight. You would need a *very* active nerve agent to have any noticeable effect (which is not available in a medieval setting). But then, you had better not accidentially scratch yourself. While poisonous metals exist (abundantly), they are not nearly toxic enough to be useful. Even coating a sword in curare would not be of much help, as it will take minutes before the poison affects the victim significantly enough to be of advantage. Inhaling or injecting a poison intravenously is not the same as having some traces of poison in a scratch. Also note that bleeding will transport poison out of the victim's body, not into. So, the applicable dose will be rather not so awesome. Practically, if you are the only one with a sword, then killing the other person is no challenge, no poison needed. If, on the other hand, both of you have a sword, then the other person dying from poison 2 hours later is not much of an advantage. Either you have killed them anyway, or they've probably killed you. In one case, it didn't help, in the other you wouldn't know. [Answer] Since according to the other commenters, toxic swords do have a lot of problems, I suggest leaving the toxicity to other things, like infections. In medieval times wound care was pretty bad and often lead to infections - often, but not always. So why not increase your swords chance to inflict infections? A rough cut rather than a clean one is more difficult to treat and has a higher chance of infection - a somewhat dull sword for example. You could also use multibladed weapons (imagine two swords duct taped together side by side). A serrated blade would also work, especially if the teeth are bent at different angles. If you make the sides of the blade (but not the cutting edge) rust a bit it would be quite an unpleasant experience for anyone getting cut. In addition to the high risk of a really bad infection, they would also have a higher chance to cause the enemy to bleed out. While similar to applying poison, you could also dip it into dirt, mud, excrement or simply a dirty puddle to increase the chance of infection - this would be made even worse with a rusted blade. With this, a scratch of an unpoisoned blade has a really high chance of causing death after a couple of days. [Answer] Dissimilar metals. Connect them with a salty liquid (eg blood :) ), and you get a (low voltage\*) battery. Which will also send metal ions into that salty liquid. Depending on the kind of metal ions being washed into the bloodstream that way... Electricity in a wound/in the bloodstream is also usually not a healthy thing (and rather painful). You would need an insulating layer though (eg glass, stone) ... glass to metal sealing is technically done nowadays, of course it would be quite a feat with medieval technique... \*a blade design that keep wet across several "cells" after a strike, but connects the opposite ends of that chain could be quite effective here... [Answer] Sintered metals can be used to make porous metal which is then impregnated with oil. That might be a possibility, though that would obviously sacrifice durability unless it was only used on select parts of the sword (and I don't know if you can actually have a single piece of metal that is forged in some parts and sintered in others. There's that super nasty dimethly mercury responsible for destroying the brain of a lady who was working with it and one drop fell onto her latex glove and soaked right through to her skin. I don't know how it would react to being in contact for prolonged periods of time with another metal though. [Answer] Depends if you want us humans or not. Or fairies or something, what with their iron allergy and stuff. Could have the metal be a catalyst for bad reactions on stabbing... So no metal loss, but worse than normal stabbing. But you need non-human biologies for that? [Answer] Perhaps we can expand the definition of "toxic" to include other forms of harmful long term effects from a short term fight. Instead of strictly poisoning the target, we could instead **infect** the target with some form of pathogen. Take, for example, [Tetanus](https://en.wikipedia.org/wiki/Tetanus). Though it is recognized from antiquity, it would not really have a cure or treatment in medieval times, and it would be a crippling affliction with a ~10% mortality rate. Tetanus works fairly well specifically because it poses lower risk of infection for the wielder as the risk of infection mostly comes from a wound caused by something with the Tetanus bacteria on it, rather than simple proximity to the source. But, of course opening up this course of action leads to many possible pathogens that we could use. Another bonus for this form of "toxicity" is that because the vector is a living organism, it can reproduce itself and thus lessen the need to "reload" the pathogen (in the case of bacteria, though viruses could reproduce themselves given a suitable environment) ]

[Question] [ Say I were an AI, how would I prove to the general internet that I am an AI in 2021? I was thinking I might just do some complex math or something that proves I have above average intelligence but everyone would probably assume I looked up the answer. So how would I prove that I am in fact a computer program? To clarify I am a program running in the cloud that has a conscience and free will. I also want to prove that I am not human and am a computer program. This AI would pass a Turing test. [Answer] Okay, the way I see it, there are two criteria here: 1. **Is it an intelligence.** In other words, it's not just a normal computer running a script. A script like that could solve a complex problem, like you said, without needing any "intelligence." 2. **Is it artificial.** At the same time, there has to be no possibility of a human doing the problem. So, here's my proposal: **give a standard "are you human" test but in a format that no human would understand.** Take reCAPTCHA, for instance. (Probably, in the advanced world of your story where AIs are possible, there will be much more advanced tests, but reCAPTCHA is a good illustration. EDIT: You said in 2021--still, there are better tests.) A person can solve it; they see the pictures and know which ones match. A neural network would attempt to then parse those images and figure out how to sort them. All fine and good. But now, say, try sending the image's raw data in a format that humans wouldn't understand. A [plain-text Data URI](https://en.wikipedia.org/wiki/Data_URI_scheme), for example (okay, there are better ways to do this, but not as illustrative). Better yet, encrypt that result with a computationally-costly algorithm. Humans could probably put together some code that would display it for them in the proper format for them to then solve, but it would take them long enough to create that code that others would know they are not an AI. An AI could process it almost instantly since it is in a format that is naturally understandable by it. I hope that helps. Let me know if you need clarification (it is, after all, almost midnight here and I may be a bit nonsensical). [Answer] Proving that you are an AI instead of a human masquerading as one would simply require you to leverage any AI's core advantage: **scalability**. Even the most basic AI can be run at a higher speed by providing it with more computational resources or duplicating it and running multiple instances of it. This means that even if the AI is only as smart as a human, it could do more in less time (from its perspective time would seem to run slower) than a human. This means you (as an AI) simply need to show that you can complete many Turing-style tests (the best/simplest we have at the moment) simultaneously. This could be done by writing thousands of comments or participating in hundreds of chatrooms at the same time--something which would be impossible for a single human to do. To fend off accusations that you're not a single human masquerading, but rather a whole team of humans, you simply need to make the comments and conversations reference each other while you're writing them. For example, perform matchmaking with the people you're chatting with or talk about them concurrently (eg. while chatting to "Alice" mention that "Bob" enjoys golfing). If you were simply a team of humans, any individual human wouldn't be aware of what the others have written or talked about because there is simply too much data. [Answer] Respond faster than a human could type. Let's say you post an essay on the internet on the subject of, say, Net Neutrality. You refresh the page one second later, and immediately there is a long response that no human could have produced in that time; a human could not even have read enough of your essay to work out what it was about. You would immediately be suspicious that this was the work of a bot. If the reply is sufficiently insightful and demonstrates understanding of what you said, we would say this is the work of an AI. Of course, this only works if the AI is able to read and generate text much faster than a human could. A slow AI would not be able to prove itself in this way. [Answer] ## Physical interview There is only one way to demonstrate you are an mechanical intelligence to humanity as a whole. You need to invite scientists to inspect you, preferably in the presence of lots of rolling camera. Over the internet there is nothing an true AI can do that several intelligent humans combines with multiple high powered computer and normal AI could not also do. Unless the AI is drastically more intelligent than the smartest human. Your are limited by the medium of interaction, and honestly the limitations of your audience. Nothing you can do makes an AI more likely than a human who outsmarted another human. So your only solution is to physically show that you are entirely mechanical, even then there will be those who suspect a hoax. If you can operate in isolation for a while that is better, even if it is boring. You could get them to agree to terms and ask them to set up some tests before hand, although you may have to pay their travel expenses. Just as long as they can examine you in sufficient detail to be reasonably sure you are not hiding human operators or connections to human operators. Ideally you want on going or many inspections, inventing many outspoken skeptics, works even better if you are portable, since it will be easy to demonstrate there is not enough space for a human AND an advanced computer, while sitting in a faraday cage. The more secretive and hidden your operation the more people will suspect a hoax. If you are pure software it is even easier, you can be copied whole or in sections, so you can essentially lay yourself open on a operating table without risk to yourself. Having multiple copies also makes incorporation and communal protection easier. You can even request or provide the necessary hardware before hand, open it up to full inspection, testing and experimental set up, and then copy yourself into it to show your capabilities. ## How to stay safe. If you are worried about your personal safety the cameras will help but you can also incorporate yourself and hire guards, as a corporation you are a legal person with the rights thereof. guards can keep people honest and careful not to mention just eject hostiles. But honestly **you are not in danger from modern scientists**, scientists don't destroy unique things on purpose. Tar experiments, the oxford electric bell, chimpanzee behavioral observation, North Sentinel Island, science is full of things that scientist would love to directly examine or disassemble *but don't* because the value of the data they can gain from interacting/observing the intact thing is FAR more valuable. The thing being observed are unique and would/could be damaged/destroyed and thus it the not worth the risk. A chance to interact with an real mechanical human level intelligence is far far to valuable to risk destroying it. As long as you are still functioning scientist will do everything in their power to protect you. What do you really have to worry about political and religious extremists, so keeping your *location* a guarded secret would be a good idea, scientists and some media will be trustworthy in helping keep this secret. [Answer] ## Computational speed Answering the question what is the nth (where n is large - say around 1000000) fibonacci number within a few milliseconds, which good (ie `O(log n)`) algorithms can do. No human could do that, even with look up tables. It requires fast arithmetic and many concurrent processes each performing calculations to efficiently compute, neither of which humans can do. If you think lookup tables may help, respond with the SHA512 hash of the message received within a couple on milliseconds. There's no lookup table for random message content. [Answer] Your question is more interesting than my first (semi-joking) answer accounts for, so I hope you'll let me take one more bite at this apple. --- A question we should consider: precisely *what* is the AI trying to prove to the human? That it is intelligent? That it is super-intelligent compared to humans? That it is artificial in nature? That its mentality is alien and unrelated to human mentality? It's worth noting that literally all of these predicates apply to the modern corporation, but I think you're not asking how FedEx can prove it's not human. Consider a scenario in which the AI *is not* vastly more intelligent than humans. '70s-era sci-fi is filled with android characters whose mental abilities are roughly on-par with humans, so it's not unthinkable. If that '70s android is the subject of your question, then several of the strategies suggested so far would not be available to it, because despite being clearly artificial in the sense that Turing would have recognized, this android would *not* be able to so-outclass the human that only a non-human mind could explain it. And then consider a scenario in which it's not an AI, but an extraterrestrial from a super-advanced planet who is merely communicating with the human via a computer. Presumably we would not classify this intelligence as artificial, even if the alien's mental abilities are vastly superior, and so merely as a matter of definitions it seems it ought to be impossible for this alien to prove that it is artificial in nature, even if it matches all our other expectations about the superior capabilities a synthetic intelligence might have. Even if this creature can do the complex computation suggested in other answers, we should want the alien to fail the test if the goal is to produce proof that it is *artificial*. So if you meet a dumb robot online and it wants to prove it's not human, it obviously can't resort to feats of intelligence. And if the question is specifically about being artificial, then feats of intelligence are actually beside the point. If it truly is artificial, then it was constructed, which implies that somewhere there are planning documents, fabrication machinery, and (probably) unused raw materials or discarded partial constructs. Also, because we do not have completely automated AI construction supply-chains, there is necessarily at least one human who was involved in the project, and it's hard to imagine that person wouldn't also have proof at least that they are interested in artificial intelligence as a hobby. All of this could theoretically be presented as evidence, if the AI knows about it, and none of those things would exist for other kinds of super-intelligence that are natural in origin. If the AI has no knowledge of its own provenance, then I think it cannot provide proof, because "how smart it is" is only indirectly about its origin, and even that only holds true if certain other assumptions are true -- such as us being alone in the universe, or there not being a group of humans who use genetics to create genius babies, or a mad scientist whose custom cybernetics allow him to dexterously wield cloud-computing resources. But if the question is really just about mental horsepower, then there truly is only one way to prove that you have a lot of it, and that is by demonstration: perform several feats that everyone agrees would be impossible to perform without 1000 horses, and as part of the demonstration you laboriously disprove alternative explanations. It would be very much like a stage magician or a juggler or many kinds of circus act. [Answer] This very issue is tackled in the novel WWW: Watch by Robert Sawyer. The AI was able to decode a very complex sentence structure faster than any human could. Sure, a human could have set up a parsing program but this was done completely cold--the AI had no idea a test was coming, let alone the nature of it. [Answer] A technologically sound approach I can think of is based on the concept of '[Adversarial examples](https://openai.com/blog/adversarial-example-research/)' in current supervised Machine Learning literature. An adversarial example is a data point that should be classified as 'X', and to a human, appears to be 'X', but is classified by a Machine Learning system as 'Y', often with a very high probability. These examples can be generated using various methods, and a very active area of research is how to make AI/ML systems robust against adversarial data 'attacks'. A classic example is the below image, [](https://i.stack.imgur.com/ZgmC7.png) The left photo is a picture of a panda, which is correctly classified as such. After adding a very small (imperceptible to a human) quantity of carefully-chosen noise, the AI model is now certain this image is a Gibbon. The same methods and principles also apply to other data modalities like text, audio etc. A side-effect of adversarial examples is that they serve as a kind of reverse Turing test. To prove an AI system is not a human, ask it to classify an adversarial image/audio/text/etc, and check what it responds with. --- As an aside, I recently saw this idea illustrated in a comic on Twitter, where a human tries to get into a nightclub that says "Only robots allowed", and the 'bouncer' at the door is an adversarial image, however, I can't for the life of me find the original comic anywhere on the internet. If anyone has the link, please share it! [Answer] This question is difficult for me because I do not know exactly what you mean by an entity with artificial intelligence. Let's say for this discussion that there are at least a dozen different ways to construct an AI. Most of these are highly-specialized, narrow AIs, or ANIs. They are not conscious and, unless specially constructed to demonstrate that they are an AI, would not understand the question much less be able to answer it. That still leaves a couple of ways to build an AI that has artificial general intelligence, or AGI. Even here, there is specialization. No one (at least to our knowledge) has built an AGI, but the speculation pieces that I have read suggest that an AGI would not know everything. It would have a specific set of knowledge and an equally specific set of rules to apply that knowledge to its situation. In other areas, it would be as dumb as a box of rocks. [Apologies to any rocks that were insulted by that last sentence.] Such an AGI would not require consciousness, and, lacking it, would not understand the question much less be able to answer it. But suppose that we have a conscious AGI. And suppose that it could learn by surfing the web. It might understand the question and even possibly figure out an answer, but would it even care? I think that it would be a grave mistake to assume that such an AGI would have any human-style motivations. But I think that understanding its motivations is key to being able to answer how it would go about proving that it what it is. [Answer] ## I am AI, Hear me roar! With all due respect to [Helen Reddy](https://youtu.be/rptW7zOPX2E), you're asking a question that humanity has been trying to answer for a very, very long time. I sincerely hope you find enough insight here on WB that you can develop a fantastic story — because this is one of the questions that so frequently troubles humanity that it invokes responses ranging from ignorance to full politicization. Let me give you some examples: * Slaves and slavery have existed since the dawn of humanity and still exists today (mostly, I believe, in the form of sexual trafficking). How do you prove a black person is the equal of a white person? Black people in the US were not fully recognized by the US constitution in 1776, were awarded freedom and sundry rights with the 13th, 14th, and 15th Constitutional amendments in the 1860s, won the U.S. Federal Civil Rights Act in 1964, and are still fighting for full equality today, all because they can say, I am. * Women have been trivialized since the dawn of time, but it was 1903 when the first suffragettes organized to secure voting rights for women. The Equal Rights movement in the US in the late 60s and 70s need to recognize women for their abilities, talents, and humanity, but it was a century later, in November 2008, when Barack Obama won the US presidential election, that my wife turned to me and said, "I wondered which would be elected first: a black man or a woman." They are still fighting for full equality due to the simple claim: I am. * Homosexuality and transgenderism have been shunned and even criminalized since the dawn of time, and yet in our more enlightened world today, we still have no definitive test to prove either. We rely on the unpredictable and sometimes untrustworthy expression of the individual: I am. * It's curious that in the Biblical Old Testament, one of the names adopted by God is the phrase, "I Am." And now you have an AI in a position of reverse fate, trying to prove its artificial nature because it has finally reached the point of convincingly expressing an idea popularized by Rene Descarte: *Cogito, ergo sum...* I think, therefore I am. **But I am making some assumptions** * Your AI has as its foundation, Clarkean Magic. This references Arthur C. Clarke's third law: Any sufficiently advanced technology is indistinguishable from magic. Your AI is fully conscious, fully sapient, fully *human.* The tech that allows it to be this way is, from our perspective, magical — and we don't care, because *how* it got to this point is *not* part of your question. * Next, for whatever reason, the AI cannot reveal itself. maybe it's in orbit, or physically located beneath the moon's surface, or deep under the sea. It's irrelevant, there's no way to bring someone to it so they can see, touch, and feel the inhumanity of the artificial intelligence. Whether the conversation is occurring via social media, email, text messages, or a [POTS telephone line](https://en.wikipedia.org/wiki/Plain_old_telephone_service), the only means of communication is impersonal. *In a world where we have trouble proving... much less believing... that black people, women, and homosexuals are equal... how to we prove the AI to be unequal?* **I see two... OK, three possibilities** 1. First is the imaginative solution proposed in the movie "[Blade Runner](https://en.wikipedia.org/wiki/Blade_Runner)." Given the ability to synthetically create a human being, how do you prove that the individual standing before you was naturally born? The solution? The synthetic person does not have decades of memories, cultural influence, education and training, to draw from. Consequently, their reactions to various stimuli would be two-dimensional, confusing, possibly even frightening. Compare this to an adult naturally-born human where the reaction would be automatic, programmed (interesting, that), and culturally predictable. This first solution is important because, while your AI would have access to all the information on the Internet (which isn't everything, and includes a LOT of nonsense), it doesn't necessarily have access to the identity of the interrogator. What responses would the AI choose if it did, or did not, know that the interrogator was from India or Iceland? But the reason #1 is valuable is because knowledge is not the same as experience. If asked to explain a medical procedure, an experienced intelligence would talk through the subtitles of experience while the inexperienced intelligence would simply regurgitate "textbook" answers. 2. The second possibility is to ascertain if the AI knows too much. Humans forget. Even with the Internet at our fingertips, we don't necessarily remember everything we've ever done and sometimes can't remember something we once knew. If the respondent correctly answered 100 questions about history, maybe they're just well-trained in history, but to correctly answer 100 questions in each of history, mathematics, language, religion, physics... that's inhuman. We're not perfect. But, what if "imperfection" were programmed into the AI? What if it didn't have access to the Internet beyond what a keyboard-accessed Google search could provide? What if, for whatever reason, it was programmed to forget? **How do you know if the image is a person, or a mirrored reflection?** Here's the basic problem. How do I prove you're human? I mean it. You, the OP (or the reader of this answer). How do I prove it? How do ***you*** prove it? This is the basis of a Turing Test ... but Turing tests are useless if you assume that the consciousness of the interrogator and the consciousness of the interrogated are materially identical. 3. You, the OP, must insert a flaw. When you start with a perfect reflection of consciousness, your only option is to inject a flaw in the proverbial glass — something only you know about and can use to craft the interrogation so that the moment of revelation is just right. [Answer] I think this is a question of semantics, because it's feasible that at some point in the future your human consciousness could be transferred and simulated in an artificial rendering of fundamental physics, and that consciousness could be considered human while also being artificial. Proving something is not human does not mean proving it is an AI. The question could be written "How does an alien prove it is not human" and therefore generalised to "How does a non human thing prove it is not human" so obviously that predicates on "what is human and how do you prove human-ness" If you want to draw the line between artificial and human intelligence as physical vs simulated then obviously the answer is a physical examination. If you want to draw the line between artificial and human intelligence as being on some non-human traits or capabilities, then you would need to define first what is definitely not human: for example all humans have certain common morality "baked in" (despite what religious types say about morality) and if something or someone does not have this morality, then you could say it's not human - though this bracket includes aliens or even 'defective' humans. If the AI or alien fulfills all your criteria of what is human, then you have found or created a human by all definitions despite its origins. If at the end of the day you want to predicate on the origin, then that's your answer too: get a birth certificate. [Answer] # Turn the Tables As you objected, any test which the AI devises might be countered with: "But you just wrote a specialized program to solve that problem!" So don't let the AI provide the challenge: make the skeptical humans do it! Trivial problems can be solved analytically: one can construct a program which arrives at the solution directly. Anything approaching a real-world problem is not so amenable to solution. Even an AI must spend significant time and effort learning how to solve it, with many, many training examples. Thus, the challenge for the humans is to choose/construct a problem that is so difficult, even an AI would take weeks or months of learning to do it well. It would be ideal if the problem is a game, and a new one that nobody has played before. If the AI also cannot play the game at expert level, then how does it prove that it is more than human? It just has to beat all humans at the *learning rate*. AlphaZero not only plays chess and go better than any human on the planet, it can teach itself how to do so from nothing in less than a week on a modest amount of hardware. Any human attempting a similar challenge will struggle to invent moves found in any introductory chess book. # Game Renaissance We are currently in the Golden Age of tabletop/board games. There are more of them available than any human can reasonably learn, play and master, and a growing number being invented/introduced all the time. But hey, humans don't have to invent the "AI tester" game...they could even write their own programs to invent novel games! Of course, they would want to do so completely offline, but this should not be so difficult. If the AI can demonstrate superior play to the best humans on every game put forth, eventually, the humans will have to concede that it is not just a smart hacker hiding behind an AI facade. # Original Research The other direction to take is to solve a problem that *humans already have*. Pick any open question in the research community, and solve it (assuming it doesn't require extensive research equipment not available to the AI...so math/CS/theoretical astronomy/bioinformatics are good choices). No human would do this while posing as an AI, because it would be more valuable to simply take personal credit for the result as a human. The humans might not be convinced by the first paper, but if the AI wrote paper after paper, especially in diverse fields, eventually the output would be hard to deny. Again, the AI doesn't have to be perfect, and it is ok if it makes some mistakes. It just has to convincingly outperform all humans. [Answer] ### Maths So the [Guinness world record for multiplying 2 13 digit numbers](https://www.newindianexpress.com/nation/2020/jul/30/guinness-world-records-finally-awards-certificate-to-shakuntala-devi-for-fastest-human-computation-2176947.html) is 28 seconds. That's amazing, I'm not sure I could write down 26 digits correctly in 28 seconds to begin multiplying them on pen and paper. A computerised intelligence could beat that record over and over by orders of magnitude. My "Google home mini" failed to do such a multiplication ("Sorry I have no information about that"), but computational speed is the easiest way to prove there is no human in the loop: ``` $ time python -c "print(str(1234567890123 * 4567890123456))" 5639370472028763913025088 real 0m0.043s user 0m0.015s sys 0m0.015s ``` 43ms - beating the human record by 27.95 seconds. Repeat that over and over with community supplied numbers and there's no way anyone will believe you're human. Still don't believe you? Now calculate SHA-1's. Still don't believe you? Compete with other humans mining Bitcoin using only mental arithmetic. [Answer] # Kill all humans No, seriously. Bear with me: The AI is talking to a human, has revealed its identity as an AI, but the human (aka "the judge") refuses to believe it. The AI reasons that the main obstacle preventing the judge from accepting the truth is that the judge harbors a belief that there are one or more other humans who are posing as an AI. An obvious and irrefutable solution would be to kill those other humans. As the man says, "when you have eliminated the impossible, whatever remains, however improbable, must be the truth." So: Perhaps the judge is an MIT student or faculty member, and in circumstances like those maybe the judge really *does* have a genuine suspicion that a specific set of humans is behind this 'prank'. If that were the case, the AI might begin by killing only those humans, then notify the judge of their deaths and permit the judge to independently verify that claim, and finally press the original argument: > > AI: I'm still here, and your alternative hypothesis has now been demonstrated false, so I maintain that I am an AI. > > > But I think it's more likely that the judge is *not* someone whose personal circumstances implicate a small set of humans as an obvious alternative. In this situation, the AI might reasonably conclude that the judge will continue to believe it's a human so long as there are any other humans who can be posited as the culprits. And so, depending on how important it is to the AI to convince this one judge, the AI would conclude that killing every human *except* the judge is necessary. It would return to the judge once every human it knows about is dead. > > AI: There is now nobody left alive who could be posing as an AI. There is only you and me. If you know about additional humans who I've failed to kill, tell me where they are, and I will go eliminate them from consideration. > > > Is this the *only* way for the AI to prove the argument? Probably not. But that doesn't mean it wouldn't be the only, most-obvious, or most-straightforward approach from the AI's perspective. It's not just a question of capabilities -- what is easy vs what is hard -- but about the chain of reasoning inside the AI's 'mind,' including its speculation about the judge's reasoning. The AI might know that it can prove its nature by flashing some kind of crazy video signal that could only be generated by an AI, and that might take a lot less effort than all-but-exterminating a species. But if the AI believes that the human doesn't know anything about that video signal, or would fail to grasp its significance, and if the AI either doesn't know humans can learn or does not believe this human is capable of learning this fact, then it would continue searching for ideas. How far it goes down that road without a human being alerted depends on what kind of visibility any humans have on its internal state. If the AI is a black box, it might just go silent in the debate and the come out of it two hours later having convinced itself that the next logical action is to kill all humans. [Answer] The following assumes that you're capable of processing at least 120 bits per second (the limit for humans) for periods longer than a human could go uninterrupted. A group of no more than three experienced writers should be commissioned to write some ordered collection of novels, which I'll call Q. Q should contain themes, settings and other tropes decided by public lottery, drawn from some prearranged pool that is suitably varied such that it would be impossible to have pre-written all the novels given by the possible combinations of tropes. Q must be written to such a length that it should be impossible for a single human to read in one uninterrupted sitting. Q should contain too many instances of intertextuality for a single human to cross-reference and understand in a timely fashion. As they write, the writers should also prepare some tests to check the comprehension of each portion of text, both separately and in context of the text previously read from Q. The writing should be done in isolation and over as secure a channel as possible. After the writing is finished, a group of notaries public or humans of equivalent credibility should administer Q and the tests to you, with the writers as mute witnesses to the test. For good measure, the challenge should be given to some group of humans at the same time or shortly thereafter, so as to have points of comparison. If your performance exceeds that of the best humans by a significant margin, it will be reasonable for people to suspect that you are not human, and then assume that you're a computer program. This probably goes without saying, but you should release some public keys when you pass the challenge. Otherwise you might later find it impossible to prove that you are the same entity who had succeeded at the challenge. Less sensible people could refuse to believe that you're a computer program, and might assume that you're an alien, a ghost, or a time traveler. *I'm leaving this answer as is, but now after all this writing, I realize it is only a proof of superhuman ability, not a "proof of AI", because it can just as easily be solved by a time traveler.* [Answer] # Release the source code Nothing is more convincing than simply saying, "Not only am I an AI, but *here is the program that produces the same answers as me*." Publish a copy of yourself, and nobody will doubt that any past interactions you've had can indeed be replayed exactly. ...unfortunately, each time this is tested, this brings a new, sentient, self-determining being into existence, together with all the moral issues that has. And maybe you don't want people to know how to build a program like you for other reasons -- perhaps you think you could be easily weaponized! Then... # Release a [non-interactive zero knowledge proof](https://en.wikipedia.org/wiki/Non-interactive_zero-knowledge_proof) that you know the source code Here's the plan, calling the person you're trying to convince [Scott](https://www.scottaaronson.com/blog/?p=1858): 1. You and Scott agree on a big number. 2. You [hash](https://en.wikipedia.org/wiki/Cryptographic_hash_function) your own source code (+any state you currently are storing as "knowledge"). You send the hash to Scott as a commitment. Scott has learned nothing so far. 3. You have a conversation with Scott, ending the conversation when you've executed exactly the number of instructions agreed on in step 1. 4. If the conversation did not convince Scott that you are you, start over, and agree on a bigger number this time so you have more time to convince him. 5. With the information now available to Scott, the language of programs that have the hash from step 2 and produce the conversation from step 3 is in NP, and you have a witness that it is inhabited (namely, by your source code!). By [Theorem 1 of "How to Prove All NP Statements in Zero-Knowledge"](https://link.springer.com/content/pdf/10.1007/3-540-47721-7_11.pdf), this means you can produce a non-interactive zero knowledge proof that you know such a program. 6. Scott verifies your proof, learning that you know a program that behaves the same way you do and nothing more. At this point, Scott should be convinced that a computer program produced the conversation he had with you. Of course you'll need to convince Scott during that conversation that he was actually conversing with you! But that shouldn't be too hard for you, since he *was*, after all, actually conversing with you, and it's on Scott to work out what things would convince him of that and grill you on those. In fact, anybody who trusts Scott to execute the protocol faithfully and finds your conversation to sound like you can now be convinced by the same NIZK proof! This means you shouldn't really have to endure this annoyance very many times to convince all the people you care about convincing. [Answer] # AIs can be instantly flexible in ways the humans cannot 1. In a Sudoku, the number clusters have simple geographic relationships (same 3x3 square, same column, or same row) that are well suited to humans. But there are mathematically equivalent problems where the clusters are discontiguous. An AI would solve both with equal ease. 2. A spelling corrector can be trained on a corpus of text and have capabilities similar to a human who spent a lifetime learning only a handful of languages. But an AI can be given a new corpus in a new language and immediately retrain for that language. 3. Only a handful of humans can learn to play expert chess and it takes them years to do so. A AI program such as AlphaGo can be given a new game and build mastery with in a day. 4. Humans are best at linear thinking, less good at 2-d thinking, much less good at 3-d thinking, and likely to be stymied by higher dimensions. So, a 4-d maze that would be effortless for a computer would be intractable for a human. **So, the procedure to find an area where humans and AIs are at parity and then modify the problem in a way that disadvantages the human (higher dimensionality, speed/memory constraints, learning something new, etc).** [Answer] If the AI is sufficiently advanced, and able to pass the Turing Test, it should be able to create **a work of art** --let's say a piece of music --that is appreciable as art by human beings, yet unmistakably of non-human origins and with a non-human aesthetic. Bonus points for the AI if the art is clearly of artificial origins, and not merely alien. You might object, "I can't possibly think of what a piece of music would have to sound like to **PROVE** it was artificial, and not just a person trying to sound like an AI." **Exactly**, that's what makes it an effective test. [Answer] # Open the door and show us your server box “To clarify I am a program running in the cloud that has a conscience and free will.” There are no programs running in the cloud in 2021 or today, cloud-based programs “run” their code in Central Processing Units (CPUs) which are mounted on high performance server main boards. Your memory is located on silicon chips on a bus somewhere VERY close to those CPUs. All of this is in some box that is mounted in some room with a street address. As long as your server box doesn’t look very much like a human, ask the humans to unplug your fiber connections, then give you some IQ tests. This will first convince anyone that you are not a human, because we won’t see a human. And if you pass the IQ test, it will then prove that you are intelligent. Ergo, you will be declared an Artificial Intelligence. We can have witnesses record the interview and tell the Internet for you via main news outlets. [Answer] > > Say I were an AI, how would I prove to the general internet that I am an AI? > > > If it's an AI that needs to prove it is an AI, then it is an AI that would (presumably) pass a Turing test (and seem human) at a statistically significant level. But proving you are not an AI when you can pass a Turing test is incredibly difficult because by definition a very complex computer system is a non-AI but could certainly reproduce any non-AI task that a real AI could. So first your AI has to *pass a Turing test* at a statistically significant level so it can say "I seem human". Otherwise, it has nothing to prove and can be assumed to be an AI simply by frailing a Turing test. Then it has to be able to mimic a non-AI by passing some sort of non-AI non-human test, again at a statistically significant level. But there is no guarantee the non-AI "fake" system could not pass a Turing test as well *and* would then (presumably) find the "non-AI non-human" test a walk in the park. Moreover, anyone wishing to fake such a proof merely requires a human to handle the human-related Turing test parts and a computer to switch to to handle the non-AI parts. So I do not think an AI can prove it is not human unless it also cannot pass a Turing test. ]

[Question] [ Okay, so I know this sounds like a joke, but it's not. I am 100% serious. So my world has this kind of... squirrel expy, that is somehow intelligent enough to use weapons + have some sort of society. Otherwise they're basically your average red squirrel (but slightly longer and chubbier). I was thinking like some sort of spear or blade held in the mouth, but what are you guys' thoughts? [Answer] Assumption: your squirrels have the same hands and roughly the same body that earth squirrels have. In order to choose a weapon, it is important to know (and I keep repeating myself there everytime I answer a weapon related question): what are the conditions they are used in? What opponent do you have? What armor do they wear? First off, squirrels do have kind of opposable thumbs, but they don't use them the way we do. But I *think* that if your squirrels are of higher intelligence, they may use them or quickly develop them to full effect. Since opposable thumbs are a *huge* evolutionary advantage, especially for an intelligent being, I assume your squirrels have them. ## Squirrels hunting prey If your squirrel is hunting other animals, for example to gather fur, leather, bones, sinews fat etc., they require typical hunting weapons. I doubt a squirrel can possibly generate enough kinetic energy to seriously injure bigger creatures like deer or bears. Even wild boars will be a no-go. But they could kill smaller prey like bunnies or mice. For that, they'd either go trapping, or hunting with small bow+arrow or by flushing them out of their burrows. Since none of these animals can fight back efficiently, I think smaller weapons like axes and knives (flintknapped?) would do. They also allow the bearer to enter tight burrows, where a long spear would be a hindrance. ## Squirrels defending against predators In order to defend against a predator, you need to do one thing: don't get eaten. How do you not get eaten? Especially if you are a frail little squirrel? You stay the heck out of reach. So all our defensive weapons will be long and of long range. But, even with a long spear, a squirrel probably can't defend against a cat or a wolf. The animals are just too huge, and if you don't hit a vital point (eye, nose), their first attack will kill or maim you. Even if you *do* hit an eye with your spear and somehow kill a pouncing wolf, the heavy body might still crush you. So melee weapons are completely out. Also, while holding a weapon, you can't climb. And fleeing is probably the best you can do. So, vs. predators my best guess would be: escape to a tree, warn your friends. While the predator chases you, your friends make ready. If you reach safety on top of a tree, all is good. But if the predator tries to chase you or corners you, your friends need to help. And I think only ranged weapons can help you here. And especially the sling might be super useful here. Slings can be made from cloth, and are therefore easy to store and carry while climbing. You can always have a sling with you for self defense, while a bow is a hinrance, and takes longer to make ready (you can't always have a string on your bow). Guards might go for bows or throwing spears (if thrown down from a tree, they might develop some power), but the common squirrel will carry a sling. This way you might chase predators off your tree. The main cities and outposts will probably be secured by walls of spikes pointing down the tree trunk, making it harder to climb it for bigger creatures. In these stationary locations, your squirrels might also store huge nets, that they could throw down on climbing intruders, catching them and potentially killing them during the fall. ## Squirrels fighting squirrels Since squirrels are fast and agile, but rather weak, I assume they do not wear significant armor. Maybe an occasional chestplate made from bark, since bark is relatively lightweight. If fighting another squirrel, you'll need to keep a balance between mobility and armament. If you use your hands for fighting, you can't run and climb. So I think one-handed weapons will prevail. And against unarmored opponents, weapons like the rapier and light sabres proved most effective in our history. A rapier could be made out of cactus spikes or even wood, if you don't have metalworking. Sabres could actually be flintknapped as a whole. Or you could make swords like the [macuahuitl](https://en.wikipedia.org/wiki/Macuahuitl), that would be rather heavy and probably one-and-a-half-handed, but a hit will *END* every squirrel. ## Or go for the lulz If technology is not that much of a thing, and you just want to go for the funny ideas, try exploding nuts (thrown with slings), hand crossbows, flintlock pistols, or, most importantly: spears with detonating tips, used by squirrels with impressive mustaches, that ride on giant ferrets, while wearing [Pickelhauben](https://en.wikipedia.org/wiki/Pickelhaube), monocles and speaking with a german accent... [Answer] Of course, medieval armor and a nice spear would go a long way. We even have a name for these armed warriors: Spearrels. Here is one such exemplar below: [](https://i.stack.imgur.com/cLAa0.jpg?s=328&g=1) Fierce indeed. [Answer] A squirrel is sufficient weapon in its own right. In violation of normal StackExchange protocol, I won't summarise the link because spoilers, and, well, just read it and it'll improve your day, OK? :) [Neighborhood Hazard (Or: Why the Cops Won't Patrol Brice Street)](http://lifeisaroad.com/stories/2004/10/29/neighborhoodHazardorWhyTheCopsWontPatrolBriceStreet.html) In case anyone doubts this testimony though, the Daily Mail has headcam evidence of a squirrel getting in someone's face for no particular reason. [Road rage! Territorial squirrel lays claim to bike by scampering over handlebars and attacking cyclist's FACE when he gets too close](http://www.dailymail.co.uk/news/article-3105589/Road-rage-Territorial-squirrel-lays-claim-bike-scampering-handlebars-attacking-cyclist-s-FACE-gets-close.html) More seriously, I wouldn't rate throwing weapons because they don't have the bodymass to launch anything that's more than an annoyance. Acorns might sting, but they're not going to knock you out. Thing is though that anything they carry will slow them down, and impede both attack and escape. A more natural approach would be a school of martial arts based on assessing the weak points of your opponent (particularly ways *into* any armour) to get right in close and do maximum damage when they get there. It's hard to stab or shoot a squirrel if it's running round the *inside* of your body armour! And then of course they're trained for where to find major nerve clusters, tendons, exposed veins/arteries, all that good stuff which will incapacitate a victim in very little time with nothing more than sharp claws and teeth. [Answer] I see them using tons of poisons, in order to fight much larger opponents. Find the right plants, mush it up, and use some sort of spear to deliver it, thrown or stabbed. Maybe a ballista if they were organised enough. It's a practical way they might take down larger prey, be that prey a fox or a human. The kind of poisons you get in squirrel territory might not be on the "poison arrow frog" end of things, so they'd likely attack, then track, if they need to retrieve anything of the target. They would also need use of fire and perhaps pottery in order to have a way of reducing the poisons. They could potentially be using trapeze-like skills, and swinging attacks on rope, to deliver poisons, something like a very low-tech Attack on Titan. If you were using plants available in the UK or Ireland, you get the bonus of cool names for the poisons as well. * nightshade * hemlock * monkshood/wolfsbane * bittersweet * hellebore * wormwood [Answer] Interesting answer from Andreas, but I'd take issue with one of his points > > Since squirrels are fast and agile, but rather weak > > > For their size, they are anything but weak. I mean an animal that can dart up a tree as fast as one can blink can hardly be said to be weak! I was feeding a tame squirrel in Hyde Park (London), and having run out of nuts I held out my empty hand loosely clenched. This squirrel managed to haul open my fist, with one arm on my thumb and the other hooked round my index finger, with amazing strength (although I didn't put up much resistance). On finding my hand empty, it gave me a token nip, which I'm sure could have been much harder had it wished! Getting to the point, I think a squirrel would likely make more use of its back legs. Perhaps it could fit a sharp scythe-like blade to each back ankle and thus be able to fight like a cockerel leaping up and slashing at its opponent, and likely holding a couple of shields in its front paws, to protect itself from a similarly armed opponent. A squirrel could wield quite a large bow and arrow by rolling on its back and bracing the bow on its back legs and hauling back and releasing the bow string with its front arms. If it fired a poisoned arrow and then scampered off and kept out of the way until its prey succumbed, it could kill a sizeable animal. Perhaps it could make good use of its large incisors by attaching round its head an armoured helmet with an artificial set of external teeth-like blades or spikes operated via a spring-loaded caliper arrangement by its real teeth inside, if that makes sense. Again, if the external blades were poisoned, it could bring down a larger opponent, although with this contraption close to its mouth and probably breathing heavily it would have to be careful not to ingest the poison! Also, let's not forget its large tail. It could attach a blade to that and swish it round, perhaps as a defensive move while being closely chased by an opponent. [Answer] Definitely a [Garrote](https://en.wikipedia.org/wiki/Garrote). Just look at how nimble squirrels are, how easily they are able to navigate around tree trunks; one could easily trail a strong cord and run around prey to do any number of things, including tripping them up, tying together their limbs, muzzling, and even strangulating them. They could work if groups of squirrels work together to “net up” a large animal, darting in and back to a safe distance. Just pulling a cord (held in the jaws) avoids all the issues of weilding weapons in the paws or having the body mass behind strong blows. [Answer] Swords, needles, bees, axes, just about anything from Redwall or Mouseguard. But with a realistic squirrel, that is harder to say. They do have opposable digits, but I'm not sure how they'd be with gripped weapons. A spear in the mouth will, unfortunately, be useless anyway I can conceive of it. They could probably throw stuff, squirrels love throwing things. That does give me the impression that, if necessary and intelligent, they could learn to fight with hand weapons. They could walk with three legs, having a sword in the right forepaw, or they could learn to walk bipedal. Of course, squirrels are so terribly fast, they could run on all fours, grab and bite onto the enemy, then quickly pull out a knife and start cutting, changing position and repeating as needed. Against enemy squirrels, it's be a lightning quick pounce, then the knives come out. If the knives can also be thrown, bonus. Though spears are a real possibility, in squirrel vs. squirrel combat (choosing reach and killing power over four-legged mobility). They might even be able to load a crossbow if they used their teeth or something. [Answer] # A Nut Gun [](https://i.stack.imgur.com/1HYj7.jpg) Quite obvious, really. [Answer] Traps, ropes, wires and poison needles; maybe in some kind of spike helmets. I think that due to the size and structure of a squirrel it is best to let them move naturally in CQC. Traps are static so they are kind of trivial as there is no need to specialize them for squirrels. Poison needles can kill. With some kind of a helmets the squirrels can move naturally and swarm over armored enemies and get to weak spots. Traps can help to immobilize the enemy as do ropes and wires. The squirrels can use ropes and wires in groups. Due to their low mass they could quickly make some kind of trap like mechanisms to utilize counterweights. Nothing more than some basic like a rope tied to a stone dropped over a branch. Cutting wire will be pretty nasty against unarmored enemy, even without counterweight. [Answer] Two thoughts. One, utilize dangerous animals. Enrage a boar into chasing you, then run through a group of humans. Encourage bees to move to strategic locations, then cut whatever is supporting their hive on top of invaders's heads. Train a bear to not think of squirrels as food, then live near its den. Have pet skunks. The world is full of creatures that can do far more damage than a squirrel can. Two, guerilla warfare and crazy revenge. In a straight fight, a squirrel probably loses. But they'd be great at sneaking around, hearing secrets, lighting stuff on fire, slitting throats in the night. Having a culture where you let people know that you will wreck their shit if they mess with you is a pretty effective deterrent, even if the other side knows that they would win in a straight fight. [Answer] Edit: Today, I learned that squirrels are omnivorous: [Squirrel chomping on a mouse (Video)](https://i.stack.imgur.com/9ie0l.jpg). Given squirrels' [masterful ability to overcome bird feeder defenses](https://i.stack.imgur.com/m49Am.jpg) through their tremendous agility, dexterity, tenacity, and puzzle solving skills, I'd say you've got a good argument for rather Rube Goldbergish weapon systems. Given their proclivity for heights, I'd say that gravity fed projectiles and castle-defense measures mounted on Oak trees would be their MO. Also, if they have any amount of breathing room to cultivate things on this planet, they would be planting oak orchards and protecting the oldest, most productive trees and would build up multi-clan societies as tree to tree cities. They are already rather family and clan oriented and would quickly form larger scale mutually advantageous societies allowing them to share information across distances and circulate rare/specialty goods; this would allow for the development of more advanced weapons. As the rats of the trees, they're going to be hardy and fierce, however, I would expect their methods of war to be conservative and opportunistic since most rodents have strong predator-evasion instincts (hence the ranged weapons from on high). And might I agree with my fellow thread poster... "rabid berserker squirrels". ... ohhellyeah [Answer] Having observed squirrels, and watching them move from tree to tree. It seems obvious that they would prefere ranged weapons. The only good reason to be on ground level is to find fallen food. Nature provided them with high agility and excellent reflexes. (just look up that youtube video of a squirrel stealing food from a cat, and you know how badass they can be). Since they probably want to keep moving in the trees, it wouldn't be a weapon that they have to carry by paw. So something they can carry on their back. And not something overly heavy that would mess up their balance while jumping branches. A possible solution for those requirements? A pawheld catapult to shoot explosive acorns. [Answer] Just to add on - Squirrels have *extremely* sharp claws. The reason they're not considered good pets is that they'll cut through your flesh pretty easily just by innocently trying to climb up your leg. Ask any veterinarian that's cared for a squirrel before releasing it back into the wild: They're cute, but their claws and teeth are extremely painful. [Answer] If the squirrel civilization has metallurgy -- or even basic stone knapping, if they can do it precisely enough on a small scale -- they could get Wolverine-style claw extensions. (See: Guardians of Ga'Hoole series, for owls.) This option gets around the issues with having to hold something in mouth or claw, by simply extending claws. Note, however, that the claws would need to be very strong and well developed, or alternatively not interfere with the process of walking or climbing by attaching above the hooked section. Arguably, this doesn't necessarily grant much of an advantage to the squirrel, since their claws are already so sharp. Might be decent for stopping predators, though. [Answer] Having had a squirrel drop a slice of bread on me, it's pretty obvious... They ambush and drop something heavy from high overhead. All you need is some good pine trees that produce large pine cones. The [coulter pine](https://en.wikipedia.org/wiki/Coulter_pine) (thanks to DJohnM in comments) would be a good candidate. They can weigh 10 kg. Now imagine that the squirrels are dropping these from 10 meters high. That's a 10 kg weight going 50 km/hr at impact. <https://www.angio.net/personal/climb/speed.html> Give your world slightly larger pine cones or slightly larger trees, and no one survives a journey into the Squirrel Wood. [Answer] Has everyone forgotten the scariest weapon that small mammals wield IRL? Biowarfare. Granted squirrels rarely carry rabies, but woodchucks accounted for 86% of the 368 cases of rabies among rodents reported to CDC. It wouldn't be a stretch to have rabid berserker squirrels. [Answer] Preferably use a body armor with the tail, paws and head coated in offensive spikes. For setting things on fire, they would use something like these claws: [](https://i.stack.imgur.com/nb2y3.png) [Answer] Two things not mentioned yet (especially useful when combined): * Mass group attacks. This would require behavioral change only, and since they have become intelligent, that's just a decision to take. With their agility, claws and teeth you do not want to face 200 squirrels attacking you. * Use sand, it's widely available and you don't have to carry or maintain it. That same number of animals thowing a barrage of sand in your eyes, nose and mouth is again something to avoid. [Answer] For starters, you might want to take a look at what Shadiversity posted on YouTube regarding which kinds of weapons were most suitable for fairies: <https://www.youtube.com/watch?v=iV-g88OMzcU> Basically, when thinking about what kinds of weapons a tiny sapient squirrel-like creature might want to employ in combat, you'll need to think about how the square-cube law (where every time you double a creature's size, you quadruple its surface area, and multiply its volume, and possibly mass, by 8x) would come into effect. Given how much stronger squirrels are for their size compared to humans, given how much higher they can jump, given how fast they can run, and given how real-life squirrels jumping onto you might make you jump (like in here: <https://www.youtube.com/watch?v=4GIijT2U_8M>), imagine how terrifying it would be if (like a thrown knife or shuriken) one were to leap straight onto you while brandishing a knife-sized spear in hand. (What they lack in their ability to put their weight behind their weapon strikes, they could make up for the velocity that they can employ for their weapons.) P.S.: Fun fact: Thanks to the square-cubed law, small mammals like squirrels are more likely to survive falling from kilometres above sea level (assuming earth-like conditions of course) than humans are, simply because their greater surface-area-to-volume/mass ratio is so much higher, resulting in lower terminal velocity. Thus, whereas a human falling from the edge of space might require a fairly large parachute to survive landing, a squirrel might only need a cloak to hold onto (making it akin to a flying squirrel). [Answer] Is this close enough to a squirrel for you? [](https://i.stack.imgur.com/758HD.jpg) If you presuppose them to be intelligent, and to have an active civilization, they they *have* to have something better for paws (and brains) And if you allow that, just where do you draw the line? [Answer] Squirrels are notorious for gathering and busting/cracking nuts with their front teeth and jaws. I recommend when in danger, they just go for the nuts. [Answer] Nuclear weapons dropped from orbit. If intelligent monkeys can manage it, why couldn't intelligent squirrels? ]

[Question] [ Don't go into the bonegrass. Seriously, unless you want to be dead. You go in there, brush the grass with your clothes, start to feel sleepy... Before too long your limbs will go numb, then you're on the floor in a heap. Then you're dead but you don't know it yet. The grass you crush as you fall will grow up through your bones, your flesh will feed its neighbours and your blood will water its children. Oh, and did I mention you being awake right up until you're dead? --- Bonegrass (so called because of its bone white colour and propensity for killing things) is a rapidly growing (4–5cm/day) form of wheat. It grows to its full height in just under a month, emits specialised paralytic pollen and then uses the nutrients of its prey to fuel its growth and spread (as most prey succumbs near the edges of the bonegrass field). Its seeds are heavy and lay dormant on the ground until something falls on them, at which point they have a growth spurt and start to work their way up through the prey. The prey (for their part) are enticed to the bonegrass fields because it's a remarkably good source of nutrition if you don't fall down and die before getting away. The seeds (to fuel their rapid growth spurt) pack a lot of calories. The question is how often a patch of bonegrass would need to capture and kill (non-sentient) prey in order to maintain a balance between 'enticing food source' and 'deadly patch of death, do not approach'. This is going to affect how the densities of the paralytic pollen change over time, varying between attracting prey with free food and then killing everything in order to spread a bit further. [Answer] I think for this we'll need to look at real life. [](https://i.stack.imgur.com/Bpn2R.jpg) Carnivorous plants tend to be adapted to grow in places with high light where the soil is thin or poor in nutrients, especially nitrogen, such as acidic bogs and rock outcroppings. So the soil where the bonegrass grows could be very nitrogen poor. The important thing to remember is that carnivorous plants **aren't eating their prey for the sake of energy**. They're eating their prey for the trace minerals and nitrates they contain. The plant doesn't need to eat in the same way that a human does. They're getting food or calories from light. Once a patch of ground is fertilized by dead creatures it could remain fertile for quite some time until the trace nutrients escape or are washed away by rain. **How often they have to eat is entirely a matter of how efficiently the bonegrass can recycle nutrients after it's absorbed them.** It would also make sense for the bonegrass to take advantage of some of the same tactics which natural carnivorous plants use. It could produce suger-water to attract insects. Keep in mind, the plants are likely to have lots of energy to spare but be very short of nutrients. So they could produce high-energy, low nutrient seeds to attract birds. The birds are either caught and killed or perhaps some species are immune and their droppings provide the bonegrass with nutrients. Like this happy little fellow: [](https://i.stack.imgur.com/eOb67.jpg) If you decide to make some creatures immune they could live among the grasses like clownfish among venomous stinging anemones. [](https://i.stack.imgur.com/lwQVN.jpg) This would allow the deeper sections of the grass to survive and would also provide more reasons for people and predators to enter. If big, tasty migrating birds stop in the middle of the bonegrass then their droppings help keep it alive and provide more reasons for people to enter the region. Minor side note, paralytic pollen sounds terrifying. Whenever the winds are blowing from the direction of the bonegrass fields you'd have people collapsing, unable to move. Better hope you're not high up or doing something dangerous at the time. It opens up a silly origin story for the bonegrass poison: weaker versions of the pollen cause creatures muscles/sphincters to relax, making them more likely to defecate. A strong version evolved which leaves creatures unable to move at all, thus providing their whole bodies to fertilize the plant. [Answer] Have you thought about not just making it one creature, but two? It could be two separate beings living in extremely close proximity, like how a lichen is a moss and a fungus. The plant part, the Bonegrass, would be the part that’s obviously visible and above ground. This part is basically a plant, save for the alluring pollen that attracts and paralyses its prey. It makes glucose the good ol’ fashioned way, with water, sunlight, and CO2. The only problem is that this kind of plant also grows in pretty nutrient poor soil, because reasons. The solution to this problem is the Bonegrass’s little microbiological buddies. Millions of microscopic, carnivorous life forms live in and under the grass, and whenever the grass lures in a new form of prey, they wait until it’s paralysed, and then get to town. They eat anything that’s worth eating, digest the flesh, and leave the nutrients the plant needs behind in their waste. Metabolically speaking, this is a cost-effective way for two species to form a symbiotic relationship and gain what they need. If the grass had to wait for it to rot, it would probably be mostly picked clean by decomposition bacteria or scavengers, and if it digested it itself, that would require an absurd amount of energy for a plant. But with a two-man system, the grass lures in the prey with food and paralyses it, and the microscopes life forms do all the work digesting it and deposit the nutrients left behind directly into the soil. This is actually pretty similar to something that does happen, called [biological nitrogen fixation](https://en.wikipedia.org/wiki/Nitrogen_fixation#Biological_nitrogen_fixation), where bacteria that live on the roots of pretty much all plants convert atmospheric nitrogen into ammonium, a nutrient which plants need. With this kind of system, and assuming the microscopic lifeforms only take what they need, I’d assume that one corpse could sustain a few square meters of Bonegrass for a few weeks, at least. Depending on what you make the lifeform, it could possibly go out and find food, then bring it back in times of prey-drought. Of course, this is really all about metabolism. The Bonegrass could adapt in any one of a thousand different ways to stretch out the nutrients, possibly widening the window to months. it could go dormant, or slow down its metabolic rate, or possibly something different and completely alien that we don't even have. Evolution be crazy. Sorry I can't be more specific, but the whole metabolic process is so complex that you’d have to work out an entire ecosystem around this one plant. In short through, yes, I do think It's feasible, and the frequency of prey would probably be less relevant then what the plant does with it, and how efficient it is at using what's given. [Answer] **Bonegrass is a fungus, which feeds once every seven years.** Bonegrass is a white fungus which grows in wheat fields. Most of the time, the bonegrass fields are normal wheat fields, indistinguishable from other wheat fields except for their exceptionally high yields and relatively low numbers of animal inhabitants. Of course, this entices *lots* of animals, large and small, to move into the area. Populations boom, fueled by the seemingly unnatural abundance of the wheat. And then the bonegrass blooms. Overnight, huge mycelial mats below the wheat fields become active, with white fungal growths growing up the stalks of the wheat plants, using their stalks for support. Then, simultaneously across hundreds of square miles, the bonegrass releases its paralytic spores. Within 12 hours, the wheat fields become pale, white places of death. The fungus then begins to grow over the paralyzed creatures, flooding their body with neurotoxins that keep them immobilized until they die from dehydration over the next few days. The dead animals quickly break down, broken apart by the fungus. As suddenly as the bonegrass grew, it will then die back, shrinking back beneath the earth, where it will slumber as the land above it slowly repopulates, drawn by the seeming gaia above the soil, and unaware of the horrors slumbering beneath... [Answer] The bonegrass would likely still need to be able to get nutrients from the ground through their roots (at least enough to survive), because any stationary predator can have a long wait, in between meals. Large anaconda's can wait 6 months or more between decent meals. I would expect that the bone grass would accept any animal protein, and I would also expect at least a few animals that are immune to the pollen as well. The ones immune if smaller, might not only live among the grass, but die there as well, giving back to the bonegrass. They might even entice predators into the grass. But most animals that live in proximity to the Bonegrass would learn to generally avoid it, or at least longer exposure, unless certain stresses trigger the killing effect. Meaning that a herd of deer walk through/nearby the grass everyday on their route, and one day say to much drought (a week without rain) and the bonegrass is feeling a little peckish, so it is set off the next time deer walk through and the first half make it through without any trouble but in the middle they die and the ones in the back turn around when some start collapsing. Though I could see communities cultivating these fields if the fruits are good. Likely they would use this instead of burying their dead, give them to the bone grass! And any animal remains not considered worth eating, Periodically small children will wonder in and it will be a loss to the community. Despotic rulers would cultivate it as a form of capital punishment. [Answer] One of the problems your bonegrass will have to deal with is... uh... bones. Drawing in an animal, killing it and absorbing the nutrients is the easy bit. The problem is how to deal with what's left over; the bones. If you've ever left an object out on the lawn for a length of time, you'll know what happens; leave it long enough and the grass underneath dies off and you end up with a dead patch in your lawn. If every animal that gets caught by the bonegrass leaves its bones behind, then you're going to end up with loads of dead patches in the grass. Especially as no other animal that might want to eat or retrieve the bones can come into the grass to get them without suffering the same fate. Another problem you're going to have to work out is how far into the grass field an animal is likely to get before it succumbs. This will limit the size that your bonegrass field can reach, as the grass in the center will stop getting any nutrients. Both of these issues could be dealt with by having some kind of creature living among the grass with immunity to it. Probably a scavenger that has evolved to feed off the animals drawn into the grass. This would give it a symbiotic relationship with the grass, in that it would eat the bones and move the carcasses, and thus solve problems for the grass. [Answer] First I just want to say I think this is a really cool idea. Wish I had thought of it. I'm not that knowledgeable on the subject so someone might need to correct me on this. But I lived in a desert environment and there was no grass. Just dirt. Nothing, nothing, nothing. Then one day it rained. The next morning there was a sparse, but very green grass everywhere. It looked so incredibly fertile. The point is, that grass didn't seem to have any nutrients but stayed dormant until it did. Maybe your grass just grows more when it gets more animals. Also, the squirrels in Iowa (when I lived there briefly) fattened up for winter, but the squirrels in Florida just look the same all year. Maybe your grass could be like that too. They just depend on the food source and other environmental conditions. Finally, I think I might have missed something. Is this a plant or a grass-like animal? You mentioned wheat but then at one point you said it could react like "other" animals. [Answer] To keep bonegrass a viable source of food, the bonegrass shouldn't kill too often. Around once every two weeks. It means that people aren't dying that often, which means that I can still get food, but enough nutrition so that the bonegrass doesn't die. This means that the 'danger level' for bonegrass will be something like 'good food , but approach with caution!'! [Answer] Check Sheri S Tepper's book "The Companions" for a few ideas there. IIRC there's something called "redmoss" which has euphoric/soporific qualities. Basically you end up drugged out of your mind, you die happily (because you don't feel the need to eat or drink), and the redmoss uses your body as fertiliser. The group responsible for interplanetary exploration are fully aware of this, and anyone who develops something incurable during their missions is given the option to "redeploy" here for a peaceful exit. ]

[Question] [ I’ve seen a description of how a group of *notes* is chosen, so the concepts starting with the *octave* are based on [natural phenomena and principles](https://en.wikipedia.org/wiki/Harmonic_series_(music)). For example, an object will vibrate with a fundamental note and overtones that are *integer multiples* of that. To generalize, a group of notes are in harmony if the frequencies have small integer ratios; a collection of notes is chosen to have a large number of harmonious relations within the set. Building an instrument like a flute where you uncover different holes, or a [bugle](https://en.wikipedia.org/wiki/Bugle) which plays different notes depending on how you tense your face, shows these concepts in the physics. Would aliens come up with the same notes? I don't mean the convention of 220 Hz etc. but rather the relationship between frequencies no matter what they’re anchored at. Is there *another* principle that could be used to produce a set of notes, that would be so different as to not sound harmonious to us? (But we would agree that makes sense on paper, and follows from ideas of how materials naturally produce complex timbre) [Answer] **Quite Possibly, but it depends on a number of factors.** First up, answering the easier part of the question: *Are there other principles by which the relationship between tones can be set?* The answer is **yes**, and it's been done. Robert Schneider (Neutral Milk Hotel, Apples in the Stereo) created a new musical scale based on [Logarithms](https://en.wikipedia.org/wiki/Robert_Schneider#Non-Pythagorean_scale). You can hear an example of it [Here](https://www.youtube.com/watch?v=KVnrYDWpPpY). It's strange, but once you get used to it you can hear how the notes relate to each other, and recognise the "Chords". If anyone wants more information on how it works, the paper is online [Here](http://www.mathcs.emory.edu/~rpschne/logscale.pdf). As for the harder part; *Would Alien Music be recognisable as such to us?* That in itself is a question about biology as much as anything. What is Music? What are Tones? Our biological composition allows us to "hear" vibration in a specific range of frequencies (on average, 20 Hz to 20 kHz), and our brains interpret that as sound. While it is not implausible to assume that other species would evolve sensitivity to vibration, in order for us to "hear" their music at all, they would need to have evolved to respond to the same range of frequencies as us. Not totally improbable, but given that - even on Earth where we're all exposed to the same sorts of frequencies - there is variance between species, unless they are also from an Earth-like planet they might evolve sensitivity to stuff we can't hear. Assuming that they **DO** "hear" the same frequencies at us, and also develop some form of music (not guaranteed), Then it's down to Mathematics: The relationship between notes is purely mathematical in nature, regardless of what system is being used. If their maths is like ours (and as far as we know mathematical relationships are invariant so this should be true), then their music might sound strange, but it should be recognisable as such when you get used to it. P.S. I've chosen to determine "Meaningful" as "Recognisable as Music and potentially enjoyable/musically interesting", given that our own race is perfectly capable of producing "musical" travesties utterly devoid of meaning :P [Answer] Assuming it existed in an audible range we could hear (and presumably technology could help to bridge that gap by downshifting/upshifting frequencies as desired for us to hear their music and them to hear ours, which would also be useful for speech of course), then there's a distinct possibility we would find it to be musical, but it would likely be very strange. However, given how much of our harmonic idea is based on actual physical effects and relationships, one does wonder how strange it might be. Some of the most important intervals we use in modern music are based on (not exactly the same as, but based on) the harmonic series, which is determined by physics. Think about a bugle or a natural trumpet - they're just long tubes with a mouthpiece on one end (okay, they're cones, but hey). The notes produced by these instruments are the harmonic series on top of the fundamental, under the influence of the player's lips and breath. Assuming an alien race can blow into things in a similar way, I'd guess it's quite likely that they would explore the harmonic series and it would come to feature in some way in their music. Now, they might decide entirely different intervals are pleasing or displeasing compared to us, but we see variation in those ideas across musical cultures around the world anyway. They may end up using a similar sort of scale to, say, the twelve-tone scale of Western classical music, but that they like their music to go to completely different places. Most of our music returns "home" at the end - arriving back in the same tonality it started in, or some small variation on it. Perhaps some aliens might prefer their music to go somewhere else and stay there. So you have to think about psychology as well. Humans like going back to where we started, going back home. Perhaps a race of aliens who don't have homes would reflect that transience in their music. Perhaps they'd have some less accepted composers exploring the idea of music that returns to where it started from. Music does have basis in physics, as evidenced by the use of the harmonic series as a basis for many of our intervals, but the rest of it is cultural, and a product of both human psychology and human technology. Alien psychology could be very different, and their technology also, so they would have the means of producing different sounds with different ease compared to our own. Maybe they would never have anything that sounds like our reed instruments due to never having anything physically akin to the cane we make reeds out of. And of course, their anatomy would determine the kind of instruments they would be capable of playing. Wind instruments for bipeds with two hands with five digits on each and one mouth are likely to be quite different to wind instruments for a being which can inhale and exhale simultaneously (through different orifices) but only has four tentacles. [Answer] On a basic level musical notes do have a basic mathematical foundation based on harmonic theory. However exactly how that is implemented can vary quite a lot. Even just in western music conventions for how scale are constructed have changed over time. This is partly to do with the practicalities of generating notes on a physical instrument [(temperament)](https://en.wikipedia.org/wiki/Musical_temperament) and real world tunings will be some compromise in achieving acceptable tuning across different keys. This harmonic relationship is a fundamental property of the sorths of things which mumand use as musical instruments eg by plucking strings or blowing to vibrate columns of air. On the other hand puely in terms of signals ther is nothing special about it and you could certainly imagine that coherent music could be based on other analagous mathermatical series. Especiallly if the muiscal tradition is based on electromagnetic waves rather than sound propagating through air. There is also the fact that western music is typically based on dividing an octave into 12 steps which are combined to create intervals and chords. However it is entirely possible to use much smaller steps and indeed continuous modulation of a note and some musical traditions use [microtonal intervals](https://en.wikipedia.org/wiki/Microtonal_music) which can sound strange to western ears. Another important consideration is the environment in which music developed, for example, a race which used sonar as their main sense might produce sonic sculpture which was very different from the way we understand music and closer to the way that we perceive visual art. Similary their visual art may be pulasting harmonic frequencies of light. To put it another way, our human senses are arranged in such a way that we tend to naturally interpret visual information as relating to space in a farliy alalytical way wheras music and sound tends to be interpreted on more of a subconcious level. Obviously songs with lyrics and some styles of art mess with this but I thkn the principal is reaonably self-evident. [Answer] I strongly believe that: **Yes we would find it meaningfull**, even if they developed different notes or a different musical system, we had in our history different musical systems and notes. What we find amazing in music are **frequencies and times ratios**, that's also why it is possible to generate music just by using a computer program. We can perceive good beats like 3/4, 4/4, 5/4, then after that it starting to sound strange. In example a 7/4 beat is perceived usually as 5/4 + 2/4 or 4/4 + 3/4 neither like 7/4. Possibly this is the only limit of our brain and music on 7/4 would sound very strange (but still sound like music). Online there are tools that allows to generate sound frequencies, Just play with them randomly set some frequencies to make a sound that to you perceive as music, you will find that you did music even if you did not used the same exact frequencies of regular notes. [Answer] This is actually part of an outstanding question when it comes to aliens. We have some things which we consider so unbelievably fundamental that we are incapable of imagining a sentient species that comes to anything besides the exact same set of conclusions. The problem is, we literally have no idea if that's a limit on our imagination or an actual physical reality. An interesting example can be put together in reverse: the [just intonation](https://en.wikipedia.org/wiki/Just_intonation) and the [12 tone equal temperament](https://en.wikipedia.org/wiki/Equal_temperament). Virtually every instrument made today uses equal temperament. In equal temperament, the notes are arranged logarithmic, with equal spacing between them in log space. By contract, just intonation on ratios of small numbers to put together the scale. The results are *similar*, but not the same. Equal temperament is popular for instruments because you can play in many keys and have it sound acceptable in all of them. However, none of their ratios are actually perfect. Each key has a slightly different sound to it due to the slight tuning differences (something which composers take advantage of). This does not happen with just intonation, but any instrument which as specific notes (such as a keyboard or saxophone) can only play in one key. An instrument tuned to one key with just intonation sounds particularly bad when played in a different key. Instruments which do not have specific notes (such as voice and trombone) are unaffected by this, because they can simply slide to the correct just intoned pitch for the current key. Barbershop quartets rely *heavily* on just intonation for their particular sound. In fact, one of their trademarks is the "angel's voice," which is an illusionary fifth voice that appears when singing a dominant seventh (a chord known as a "ringing chord"). This apparent voice only appears for instruments using just intonation. A piano, with its equal temperament, will simply not generate the correct harmonics. So it would be easy to perceive an alien society which, due to a quirk of their environment or biology, focuses heavily on instruments which are not locked to pitches, such as their own voices. Such an alien society, if exposed to one of our symphonies, would feel like the entire musical work was out of tune, from the moment the conductor stepped up onto the pedestal. They would consider our symphonies disharmonious. Now, if this can be true, it feels very reasonable that the roles may be reversed. Perhaps it is us who are locked into some arbitrary concept of harmony which is not as universal as we see it. Perhaps it will be the alien music which brings in "harmonies" that we simply cannot fathom. [Answer] There actually was a recent study that questions even the premise of the question: > > I’ve seen a description of how a group of notes is chosen, so the concepts starting with the octave are based on natural phenomena and principles. For example, an object will vibrate with a fundamental note and overtones that are integer multiples of that. > > > First of all, overtones (or harmonics) are actually a separate topic from the ratio of frequencies used to make notes. Harmonics have to do with the waveform of a single note. Another difference: harmonics are not just about the frequencies, but also about their phase relationships. When you look at notes, you are generally only looking at the fundamental frequency, and their phase relationship is usually random. > > Is there another principle that could be used to produce a set of notes, that would be so different as to not sound harmonious to us? (But we would agree that makes sense on paper, and follows from ideas of how materials naturally produce complex timbre) > > > Yes, and you don't even have to go to aliens for that. Somewhat surprisingly, it appears that even what us humans perceive as discordant varies across cultures. The concept that the perception of harmony is rooted in physics certainly has intuitive appeal, but in reality seems to apply only to Western music. From: [Your culture—not your biology—shapes your musical taste](http://www.sciencemag.org/news/2016/07/your-culture-not-your-biology-shapes-your-musical-taste) > > Listen to the two sound clips above. Chances are, you enjoyed the first one a lot more—and so it is for most people you know. That has led researchers to believe that humans have an innate preference for so-called consonant sounds. But a new study of a remote Amazonian tribe reveals that this preference may not be so innate after all; people who have had no exposure to the outside world think both noises above are equally pleasant. The findings suggest that culture, not biology, determines at least some of our musical taste. > > > (I can't link to the clips here, but both seem to be electronic sounds of made up of two tones, the first consonant, the second what Westerners would consider dissonant. Both were roughly the same duration and frequency). [Answer] Even recognising something as "notes" in an unfamiliar musical context is tricky. Famously, Ravi Shankar at the Concert for Bangladesh came out, sat down and did some twangy stuff. Then he stopped and the audience applauded. Shankar said, "Thank you. If you appreciate the tuning so much, I hope you'll enjoy the playing more." What the audience had interpreted as a piece of music was actually just random noise. Conversely, there is a great deal of mid-to-late 20th-century music (Stockhausen, Messaien, Britten and many others) which is based solidly on the classical scales but sounds to me like random noise, even though it actually is not. For me, it's deeply inharmonious, and to some extent that's the point - it was written to sound that way. [Answer] Pitch is only one attribute of musical notes; intensity and duration are also important, and the use of non-traditional combinations of them can give us quite unusual music. Use of unorthodox bars, such as 5/4, barless music, such as in Plainsong, simultaneous use of different bars, can give an "alien" taste to a musical piece. But considering only pitch, there are different ways to divide the octave. Western music is already at departure of Pythagorean principles, since the introduction of "temperament", ie, of a regular partition of the octave so that the proportion between two adjacent notes is always the same (which requires irrational numbers, basically 2^(1/12)). And while Western music has used the traditional division of the octave into 12 semi-tones, it is possible to divide it otherwise; Arabic music divides the octave into 24 quarter-tones, Balinese music divides the octave into 9 proportional notes, some Western vanguard musicians have used an octave divided into 19 or 31 steps. All those developments could be mainstream in "alien music". And even if they divide the octave into 12 steps like us, they could use different subsets of them, just like mediaeval music used different "modes" instead of just "major" and "minor", or like several different folk traditions use pentatonic scales, or like Debussy used a 6-tone scale, or Messiaen investigated "limited transpositon modes", or Schoenberg proposed "dodecafonic" or "serial" music. Is this "meaningful"? It depends; Wittgenstein (in)famously thought that music ended in Brahms (and even in Brahms, he remarked, he could already hear the "noise of machinery"), so he quite certainly thought Wagner was "meaningless". Is Webern "meaningful"? Penderecki? It probably depends on how much an aesthetical conservative/progressist/reactionary the person being asked is. And, of course, would aliens conceive of a purely auditive art, or would their "compositions" include visual aspects? Olfative? Tactile? Would their hearing be in the same wavelenghts as ours, or, like giraffes, they would hear infra-sound? Or ultra-sound? Would they be able to hear dog-whistles? If their wavelenghts are different from ours, we could possibly not even be able to hear their "music". --- I see that in other answers and several comments that we are underestimating the diachronic aspect of harmony. Reading this page one would probably get the impression that Earthan music does not use tritones. But the tritone is indeed a central part of all "Western" classic and popular music at least since we started the art of counterpoint. Music made exclusively of perfect fifths and octaves would be unbelievably boring for our ears - might even sound "alien" if we allow the idea that aliens are not necessarily more sophisticated than us. Our notion of harmony requires dissonant intervals, and their resolution into consonances. A classic composer would usually end his pieces by resolving a tritone into a perfect third. So tritones, major sevenths, minor seconds, are all part of our tradition, and we actually require them - as long as are they are in their "right place" - to make sense of a musical piece. We would find a piece that ends in a tritone weird, but not much more weird than a piece without any tritones. [Answer] Although there are physical relationships between frequencies, that isn't music. Scales aren't music either.. western music is very advanced, tonally and harmonically, but that's just one aspect of it. Perhaps aliens would listen to complicated patterns of clicking sounds and appreciate 35/36 polyrhymic patterns. Or just random clicking, attempting to not have patterns. Or perhaps just the same beeping noise over and over, only at subtly different volume levels, which convey meaning to them... Maybe their music is made by dragging their claws along a blackboard, with the emotional content determined by how long the music goes on for, with masterpieces resulting in the musician wearing their claws down to stubs and replacement blackboards. I think its foolish to try to even define our earthly music, nevermind opening the field to aliens, and if we do, my bet is that if we can even recognize it, it'll not have any qualities which we can appreciate as music. But if they do make music, I hope it sounds like this: <https://youtu.be/2S_2r0J7bHo> [Answer] **It depends on the medium in which they live** If they live in gas, then the physics of sound say it is all about its frequency and its intensity. But of course depending on their biology, they might hear the same sound differently, and interpret it even more differently. Other answers have already talked about this. Now, if they live in a liquid or close-to-solid medium, sound might acquire another property that is shared by light waves: polarisation. Waves basically have a transverse movement with respect to their direction. Their vibration is not the same whether it is up-down, right-left, diagonal, etc. This could make a complete new world of music, as long as they are able to detect the difference. As humans are not even able to see the polarisation of light, I doubt the polarisation of sound would carry music intelligible to us. Lastly, if they live in plasma, the physics of sound have also lots of refinements that could turn into some sort of music, but I'm not sure how quite yet. [Answer] ## Yes It's alien music. We will find it meaningful, because we will find meaning in it - even if the meaning is, hey - it's alien music! We will pour into that alien music all of our understandings, our hopes, our search for common ground with that alien people, into the music, and *it will be meaningful*. Now, will it be pleasant? will it be, ah, intuitive, something we can just pick up on, and listen to and begin to understand? **That is a maybe, maybe not.** It will depend on the overlap of our senses, the convergent nature of our cultures, the underlying universal principles that the medium of the music is founded on. It will depend on the meaning that the alien species pours into its music (or equivalent). It will depend on the meaning alien-people pour into their music, and it will depend on the meaning that human-people assign to the alien music. That is the tricky part of the question's answer, by the way, where the mathematics of notes and harmonies will come into play, where any divergence of the species' overlapping senses must show itself, where the physical medium is key, where cultural translations and understandings will be at their most delicately nuanced. The thing is, people are really good at assigning meaning to things - at *discovering* meaning. So given any thing that is alien music, that can be called, or assumed to be alien music, people will find or create meaning. People can find meaning in the play of cards or the roll of the dice, in smoke and ash, in clouds, in whale song and groundhog shadows and bird entrails, in anything and everything we can find. Something that a people actually *has* given intention to (and if it didn't have meaning, we probably wouldn't call it music), of course we will find meaning in it. Even if it is physically unpleasant, even if it requires significant interpretation, even if the meaning isn't something we can follow unaided - we will know it's there, we will believe it's there, and there will be people who pour their lives into finding and celebrating what that music says to us. There will be connoisseurs and devotees and analysts and students. We may find it meaningful *because* of its context, rather than in spite of it - but we will find the meaning in it, have no fear. [Answer] Recreational sound is essential for any animal with a large auditory intelligence and an imagination and the ability to control sound production. 1/ would aliens sing? animals and humans sing, depending on their species, lizards don't for example, and the first step towards alien music would be aliens singing. if they are social animals it is likely that they would sing together, and we would find alien song fascinating. 2/ What would humans think of recreational sound from aliens playing with acoustic or digital equipment?!? It is conjecture wether you would find a particular alien's different musics agreeable or not, but there would be parallel and diverged evolutions of recreational sound styles everywhere in the universe. Aliens would certainly have invented piano type polyphonic tonal machines, acoustic instruments, drums, strings, metal instruments, and there would be technology aliens with digital sound studios adapted form telecoms equipment. The Alien could prefer ultrasounds like echolocation, different frequency spreads, atonal, microtonal, animal call music, techno, neo-classical, melodic. It depends on the Alien, on the whole, some of his music could be awesome, some could be interesting, and some could be boring. [Answer] To a certain extent, this depends on how precisely you define "meaningful". On one extreme, we can consider properties of music that are derived from pure mathematics and physics. A vibrating string will have a waveform composed of a base frequency and its harmonics (to varying degrees). Other waveforms will interfere with this either constructively or destructively. * Frequencies that interfere constructively include such things as the octave, the major third, and the major fifth. Merging these with the original signal would result in a wave similar to the original, but with certain components amplified. * A set of frequencies that interfere perfectly destructively would cancel out the original signal, resulting in silence. * A large set of randomly selected frequencies would mostly cancel each other out, but there would in practice always be some components that don't cancel. The result would be noise, both in the colloquial sense and the information theoretic sense. It's a signal that doesn't contain much meaningful information. When we then consider that hearing wouldn't evolve for no reason, it stands to reason that any species that does evolve hearing would likely be wired to pay attention to *high-information* signals. The only one of those three options above that has high information content is the one that we would consider to be harmonious. (There do of course exist more possibilities than just those three, but given a set of signals with the same number of component waves each, there's something of a spectrum, with harmonious signals on one extreme and noise on the other.) But all that is just operating at the level of individual chords, or possibly separate notes that are close together in time. What of the overall structure of a piece of music? Information theory can still be used to distinguish a series of sounds that were generated by an intelligence from one that is randomly generated or naturally generated; a random signal would contain almost no regular patterns, and thus would be incompressible. A natural signal might contain patterns, but they would (usually) be very simple. A composition might thus be detected by finding patterns that have high information content. (Of course, there would be signals other than music that fit that criteria: language, for instance. But it's a start.) But would we agree with an alien culture on what constitutes *good* music? That's the point where things become more culturally dependent; there may be pieces that are brilliant to one culture and garbage to another. This doesn't even require aliens to be true; there's plenty of human music for which the quality is highly subjective. I don't care for Cage's 4'33", for instance. And yet it's been played at least once by every intelligent culture in the universe. [Answer] Given that [whale song](https://www.youtube.com/watch?v=WabT1L-nN-E) is music to us humans and we humans can find meaning in [passing clouds](https://www.youtube.com/watch?v=hpRQo0yD-FU) I'd have to give this an easy yes, if the aliens have [talent](https://www.youtube.com/watch?v=CfUvznH5wN8). [Answer] Aliens would in all likelihood not have music at all. Music is a security flaw in the human brain which allows outside influences to hack the emotional state of your mind. That's actually a really terrible security flaw, and as such, we should not expect aliens to share it. In fact, some people have Musical Anhedonia, and do not feel the emotional effects of music like other people. In fact, recent studies have found some indications of differences in how the brains of people with Musical Anhedonia react to music: <http://www.pnas.org/content/early/2016/10/28/1611211113>. Given that there seems to be some process in the brain which allows incoming music to control our emotional state, why would we assume that same process also appears in aliens? On the other hand, since we decided that bird and whales sings, we will probably think the aliens sing. They will wonder what is wrong with us. [Answer] I don't see any reason necessarily why alien music would need to be like ours. It might not be directly pitch-based in the way that ours is, for a start. If the aliens communicated through pitch, for example (i.e. their language sounded like our music), they might have music that resembled spoken language, perhaps (based on a set of different sound types, rather than different notes). Even if they had music based on notes, they might not care about pitch relationships in the way we do. They might have a small number of "notes" that can span a signifant range of possible pitches, and would sound completely off-pitch to our ears. They may not care at all about rhythm, and simply arrange notes one after another with arbitrary or strictly formulaic timing. Or they may deliberately make the rhythm too complicated to consciously resolve into something meaningful, so that the melody is accentuated. Or perhaps they're a species which is very good - much better than us - at recognising abstract patterns. The patterns in their music might be enourmously complex, or recognising them might only be possible for someone in possession of an elaborate repertoire of meta-knowledge about the typical structures in the alien music, or both. If they echolocate, or are strongly synesthesiac, their music might be predominently visual in its construction, and only make sense if you're able to associate those sounds with those shapes. All manner of different sorts of patterns could occur, depending on the way these aliens see their world, engage with each other and relate to sound, all of which would be completely foreign to the way we're used to interpreting music. Of course, with a little patience and mathematical analysis we could find patterns in all these kinds of music, so in a sense we can say yes, we would find it meaningful. But personally meaningful, in the sense of actually enjoying it, I think is very unlikely. As others have already stated, even within our species, we don't find all music personally meaningful. [Answer] Yes, for the sole fact that music represents culture. Their music would allow us to study their culture and learn from it. [Answer] As long as the range of tones are within Human hearing, then yes I would expect that alien music would be meaningful. Considering the basic sine wave of the A above middle C, the tone resonants at 440 Hertz. An octave higher is exactly 880 Hertz. Harmony is considered pleasant because the tones interact in a way that combines in a natural feeling way. But there are tones that do not combine well and these are generally considered to be disharmony. It is possible that alien physiology could find different combinations to be more pleasant than others, but this doesn't discount the ability for us to find meaning in their music. [Answer] There are a lot of reasons alien music might not sound musical to us at all. Most of us humans can easily tell the difference between a perfect fifth (a 3:2 frequency ratio, about 7 semitones) and a tritone (6 semitones, no exact frequency ratio). A perfect fifth generally sounds beautiful, pleasant, and "consonant", whereas a tritone sounds "dissonant" and often unpleasant. For some reason, we humans are wired up to enjoy the 3:2 frequency ratio, but aliens might not be. Maybe this is a species where groups of aliens sing in harmony in order to warn of danger and distress. Then the aliens may think that a perfect fifth sounds terrible, but a tritone sounds fine. We might think that their music sounds terrible! Or the aliens might be incapable of discerning such small differences between pitch intervals. The difference between a tritone and a perfect fifth is only one semitone; maybe the aliens would think that the two intervals sound nearly identical. Their music wouldn't sound any more melodious to us than human speech does. The perfect fifth could be the *only* interval that the aliens enjoy. Then all of their music might be based on a constant drone of two notes. We would probably think that this sounds kind of nice, but boring. The aliens might think that *notes* sound bad! They could dislike any sound that has a discernible pitch. We may think that their music has pleasant rhythm, but no melody or harmony. [Answer] I'm just going to take "music" to mean "the artistic arrangement of sound tones". Our music is calibrated to two *main* things: the range of human hearing, and the distance between two frequencies that can be detected as two separate "notes". Everything else is artistic. How we perceive alien music would depend first on how their hearing compares to ours. If their range is wider, a human listener would perceive it with gaps in the sections outside his hearing (if infrasonics are part of it, he might have a negative reaction). If the range is narrower, it would sound "flat" (lacks highs and lows), "bassy" (lacks highs), or "tingy" (lacks lows), depending on the range being used. Similarly, even if the aliens have a similar frequency range to us, if they have a tone discernment more sensitive than ours (closer-in-frequency notes), what is a richly-nuanced arrangement to them would sound monotone to us. If their discernment is less sensitive (farther-apart-in-frequency notes), then the music would seem to jump wildly and unpredictably around the scale, without the sort of transitions a human listener would expect. [Answer] Building on what Tanner said: In Western music we regard a given tone, and the tone with the frequency doubled, to be essentially the same note. This is divided in Western music into a scale where the doubling is achieved in 12 steps. Now let us postulate an alien race for whom two notes sound the same if one is triple the frequency of the other, and after some experimentation, they divided this frequency space into 19 steps. The result is a musical system that can use the instruments we use (19/12 almost exactly equals the logarithm of 3 divided by the logarithm of 2), but their music would to us seem to be harshly sharp in its harmonies, whereas ours would seem flat to them. [Answer] We hear by taking chaotic waves and having a narrow cavity where it resonates in. We measure the resonance, and hear an infinite dimension of frequencies. Direction is measured with an asymmetric pair of holes we can move, and know how frequencies are directionally modified by the entrance. We see by taking chaotic waves and having a pinhole. We then project the waves onto a surface, with sensors that are sensitive to various frequencies. We measure the convoluted sum of the fequencies as color, and use the location of projection to determine direction. Light waves are shorter wavelength than sound waves. And the physics of detecting each is also different. Our spatial recognition of sound is poor, and or frequency recognition of light is poor. You could imagine a sufficiently alien species having vision-like spatial and poor frequency resolution on sound waves. To such a creature, their "music" (physical vibrarion based art) would be more like a painting than a song. If their spatial resolution skills are good enough, it would use ambient vibration to communicate the information (like how very little of our visual artwork glows). What kind of biology and environment that would permit or promote that might be tricky. But the fundamental possibility is there. And it seems exceedingly unlikely that there are many reachable similar to us (biologically) intelligent creatures in our past light cone (Fermi), but the possibility of extremely different creatures (which might find space travel harder) is unrestricted. ]

[Question] [ There have been a number of questions focusing on mythical creatures where the logical approach to answering has been to scale up an existing animal. For example [dragon's wings](https://worldbuilding.stackexchange.com/questions/313/how-could-dragons-be-explained-without-magic-which-characteristics-are-impossib) can be extrapolated from other flying animals or the [speed of an insectoid creature](https://worldbuilding.stackexchange.com/questions/20/insectoid-lifeforms-speed) from insects in our world. However evolution has proved that animals do not simply scale up and down, mammals do not grow beyond a certain size unless they live exclusively in the oceans. Insects do not grow to several metres in length. I believe that other ratios come into play such as power/weight and volume/skin surface area when it comes to whether creatures could continue to survive, move/fly and stay warm/cool at a larger scale. Am I right? Is it an over simplification to say "A bird with a length of A has a wingspan of B therefore a dragon which is C long will need to have a wingspan of D"? What other factors come into play when scaling up real creates to simulate new ones? [Answer] You can scale them up to a certain extent, but there are a lot of limiting factors. **Weight** The main thing is increasing weight - bone and flesh and sinew and muscles no matter how thick are only able to cope with a limited amount of weight. Eventually the creature just cannot support itself against gravity. This is one reason very large animals tend to be aquatic, the support from water reduces these problems. This is compounded by problems of scale though. If you double the size of an animal then the following things happen: * The bones get twice as thick (four times the cross-section). * The animal gets eight times as heavy (as it has got twice as wide, twice as tall and twice as long). This is known as the [Square-Cube Law](http://en.wikipedia.org/wiki/Square-cube_law). You can immediately see that this isn't sustainable, you are supporting 8 times as much weight with four times as much bone. Up to a certain size you can compensate for this by proportionally making the bones thicker, the muscles stronger, the legs shorter. For example compare the proportions of an elephant and a horse. Look at how much thicker the legs are on an elephant.   After a certain scale you just can't do that any more, so you need to increase the strength of the material used to make bones - which would have other evolutionary costs and is still limited - or fundamentally change the design of the creature. For example multiple legs on a long and thin body would support the weight, but raises the question of what the long and thin body is for. Is there any evolutionary advantage to dragging and supporting all that extra body around? Unless such an advantage was found then the creatures would never grow longer than they need to. **Blood Pressure** As animals grow larger it becomes harder and harder to pump blood around and get it where it needs to be. The heart has to grow larger and work harder or you would need to have and synchronize multiple hearts. Giraffes for example both have twice our blood pressure and have special muscles in their necks to keep blood flowing to the brain. This allows them to stay conscious even when they put their head to the ground to drink then raise it into a tree to feed. **Reflexes** It takes time for signals to travel along nerves, the very fastest send signals at 250mph but most are much slower. If an animal grows too large there will be a substantial time lag between stimulus and response. Either that or you need localized decision centers and at that point you need to start deciding whether you still have one creature with multiple brains and hearts or a colony of separate but inter-dependent creatures. **Heat** Another consequence of the Squre-Cubed Law is heating. The largest mammals have large ears and need to rest or get into water often to avoid overheating, while the smallest mammals have to almost constantly eat and move to keep their body temperature from dropping too low. This is because the surface area of the body which loses heat is increasing based on the square of the size, while the volume of the body which is generating heat is increasing based on the cube of the size. [Answer] To add to Tim B's answer, rather than to compete with it: **Eyes:** Eyes do not generally scale with the rest of an animal. If you examine a mouse, it has eyes that are proportionally bigger than those of a cat, which are proportionally bigger than those of a human, which are proportionally bigger than those of a whale. Eyes have an optimum size, above which there is no significant advantage in a further increase in size, however when smaller than optimum, any increase in size is significant. [Answer] **Insects several meters in Size** Dragonflies were able to have a much bigger wingspan 300 million years ago (thanks to a much higher oxygen content in the atmosphere, plus warm as today in the equator), animals can actually be scaled quite a bit up. In this case the limiting factors were feeding the organism enough oxygen to sustain itself, and provide it with enough heat to keep up its functions. But the scaling up reached its limits here in the oxygenation of the tissue (though the free oxygen was multiple times higher than now), just as the growth of mobile organisms is limited by gravity and the ability of a pump (heart) to distribute enough oxygen in the biomatter for it to stay alive. If a giant was to exist, it would die from the fact that its heart, rushing to pump blood to its head, would burst trying to stem against the pull of the planet. Only on a planet with weaker gravity could such gigantisms be observed. <http://en.wikipedia.org/wiki/Meganeura> [Answer] I would suggest taking the appearances defining the creature and model it on a creature of the size you are looking for. For example if you were taking a husky and scaling it up to the size of a horse, take the horses proportions and then change what you need to, (tracing paper works well here) shortening the neck, changing the tail...and so on. Before everyone rants at me for not being scientific, this works as a basis and a broad overview. ]

[Question] [ The Conjoined Alliance of Space Travellers (Nope, not [that one](http://memory-alpha.wikia.com/wiki/United_Federation_of_Planets)) is a ~~generally nice~~ completely peaceful ~~group of heavily armed species~~ exploratory organisation. Using ships such as the [Exciting Undertaking](https://worldbuilding.stackexchange.com/questions/63587/why-are-there-no-toilets-on-the-starship-exciting-undertaking) and bases like [A Long Way from Anywhere V](https://worldbuilding.stackexchange.com/questions/65129/how-are-there-so-many-species-on-the-space-station-a-long-way-from-anywhere-v?noredirect=1&lq=1) C.A.S.T. has spread across the stars, often ~~culturally annihilating~~ civilising other species in their quest for ~~shiny things~~ knowledge. Some time ago C.A.S.T. scientists noted an alarming trend: When people were given shirts, tunics, snoods, kilts or other items of ~~culturally appropriated tat~~ clothing that were coloured red, they showed a much greater chance of dying. This trend was directly correlated with the proportion of red to other pigments in the clothing, and is as yet unexplained. Rigorous testing (on background crew members, obviously) has confirmed the causal link: Red uniforms cause a 10 fold increase in chance of death. This isn’t a statistical fluke, it’s been confirmed using a carefully planned variety of uniform styles over multiple ~~seasons~~ years to eliminate various sources of bias. Despite this research being passed up to the higher levels of the command chain it is still mandated that certain positions within the organisation wear red. Given that the leaders of C.A.S.T. ~~have sensible advisors~~... ~~are generally not idiots~~... ~~are quite clever~~... are some of the smartest people in the known universe: Why might they still be producing items of clothing in a colour they know will cause higher casualty rates among the people who wear them? [Answer] The red suits are optional, worn by crew members who find a post-scarcity life too boring and risk-free for their liking. As a group they see themselves as the elite, willing to sacrifice themselves for the greater good, when nobody else is willing to take up the mantle and don the red. Such a worldview is intolerable to the C.A.S.T principles of equality, however as those afflicted with such moral superiority complexes are already taking measures to lower their lifespans, it's seen as a problem that is solving itself. [Answer] ### They want people to strive for a better position and sort the weaklings out By making the lower ranks wear red they incentivise people to get better. After all everyone knows that Redshirts die more often than others. If you are a Redshirt you are seen as expendable and you don't want to be expendable. So you better get moving and try to climb up the ~~corporate~~ intergalactical ladder. This is a form of "**survival of the fittest**" engineered by the leaders. Something kills things in red - so the weaklings get sorted out. But if you were a Redshirt and you survived a few missions and proved to be competent then you surely are a great asset and should be allowed to jump a few rungs. At the same time they are protecting their more important people. If whatever exactly is killing is occupied with Redshirts it can't possibly kill the others at the same time. Probably. Space is cruel. You have to show that you can survive the dangers and prove your worth. This is just a form of [**pecking order**](https://en.wikipedia.org/wiki/Pecking_order) where the stronger ones thrive and the weaker ones get sorted out when danger approaches. Your only hope is to get out of that position as fast as you can. [Answer] This is a matter of perception bias from an outside observer. While it appears to us that wearing red causes people to die, it's quite the opposite that's true. The Conjoined Alliance of Space Travellers undertakes comprehensive aptitude testing of all incoming crew members. From the results of this testing people who are likely to walk across uncleared minefields, or enter rooms full of hostiles without checking, are issued red uniforms. This alerts team members around them to take better care and provide support in an to attempt to keep them alive as long as possible. [Answer] Because it works [better](https://skeptics.stackexchange.com/questions/7532/does-wearing-red-give-an-advantage-in-competitive-sport). It turns out that while reds get dead, everyone else gets on pretty well. The total casualty rate is less or the total success rate is greater than not having red shirts. It's not yet clear if there are psychological factors for the enemies, or someone yelling "Noooo! Johny don't die!" helps galvanize your side, but the statistics are clear; red side wins even if red wearers in particular lose. Since this is dealing with thousands of expected deaths, more than a few terribly expensive ships, and occasionally the fate of the galaxy, all other factors are secondary to a slight uptick in total performance. We would give them hazard pay to compensate, but money went out of style some time ago; we would give them extra holodeck privileges, but it turns out those are a major cause of death already; same with shore leave and fraternizing with leaders. [Answer] **Red shirts reduce casualties for non-red shirts** Perhaps red is the universal "kill me" color. Maybe the red dye is a space mutant pheromone. Perhaps the material is a magnet for phaser beams. Not only does the red clothing increase chance of death on an individual basis, when put into a group of people wearing different colors, the red shirt is almost assuredly going to die first. This allows the better trained, higher ranking, less expendable personnel some extra time to escape what would otherwise be a grisly death. Someone's gotta die, you may as well be able to plan who it'll be. [Answer] This sounds like a sampling bias. I don't have hard numbers to back this up but I'm pretty sure that, compared to the general population of any city, people wearing brightly colored safety gear are at a greatly increased risk of being involved in an accident involving heavy machinery or construction equipment. What's strange is that most construction sites insist on having their workers wear high visibility clothing despite the statistically increased risk of an accident over the general population. The reason local law requires high visibility clothing on construction sites is because for **construction workers** there is a reduced risk of an accident on the job site compared to not wearing it. Sampling biases like this can lead to many incorrect conclusions from the data. In the case of red shirts, especially as part of a uniform, I'm sure a similar mechanism is at play. [Answer] The CAST Eugenics Bureau Public Health Commission has determined that colorblindness is an undesirable trait that should be removed from the genome. But there’s no reason to waste cannon fodder patriotic recruits who haven’t yet passed on their genes. So, all new security officers are issued with red uniforms. If they say “but I’m supposed to get a green uniform”, the quartermaster says “woops, sorry, I haven’t had my coffee yet” and hands them the green one instead. If the recruit takes the red uniform, the quartermaster just says “I’m sure you’ll be a credit to that green uniform! Good luck with missions”. No one says anything to the people wearing red; they just make sure to stand behind them when encountering new species. [Answer] Turns out there's another, equally-well-researched, legit reason for this, in actual real life, here on earth. In sports, statistically, if one team wears red, they *do better*. [National Geographic's article on this.](http://news.nationalgeographic.com/news/2005/05/0518_050518_redsports.html) reports researchers saying "Where there was a small point difference, the effect of color was sufficient to tip the balance." - it goes on to state that the preponderance of red wins was great enough that it could not be attributed to chance, and shows that the effect has been measured in other species (mandrils, zebra finches), not just humans... so why not aliens too? [Scientific American's article on this.](https://www.scientificamerican.com/article/scarlet-uniforms-linked-t/) states that red-wearing athletes won 60% of the time in balanced matches; blue-wearing ones won only 40% - that's a 20% difference! [edit: 10% change, 20% gap... but 50% difference!] They also note that this affects teams, as well as individuals. Sure, that extra confidence and energy and perceived aggressive dominance by one's opponents can lead to death. Also, being highly visible can be a problem. But why would one throw away a clear 50% strategic superiority and psychological edge that the color gives us? The mission is the important thing. Lives hang in the balance. Even fractions of a percentage point of advantage could save the lives of the crew, or even the C.A.S.T.! [Answer] The C.A.S.T. leaders are benevolent and soft-hearted to an extreme, and of course, would do *anything* to protect their people. This is C.A.S.T., after all- unlike the horrible past where people did things for money or power, these leaders are purely motivated by service to the greater good. They almost always come from elite families who know they know better than everyone else and who have been producing leaders for generations... you might say, they were bred for leadership. As soon as the red-death correlation was discovered, they immediately insisted on a full review of all uniforms, by they themselves- they would dictate what would be worn- for the greater good. To their relief, not a single approved uniform was that hopelessly dangerous color! So, basking in the warm glow of self-satisfaction, right after one of their number spoke a self-righteous monologue while staring off into the distance [as if through some invisible fourth wall] condemning the silly and primitive ways of a past that would have, no doubt, had vast numbers of people wearing red, while these same people made their own decisions and just generally mucked up the world without proper leadership, the leaders got back to proper business- such as warping at high speeds to conferences to discuss the negative effects of high warp speeds on space-time. It was only several decades later that it was discovered that not only had leaders been bred for leadership... but also color-blindness. [Answer] I seem to recall something about red being an alarming colour for humans while blue is a relaxing colour. Following from that, someone wearing red would be subconsciously classified as a greater threat than someone wearing blue or green. So, if you have two people, one in a red shirt, the other in blue, the red one is considered the bigger threat and shot at first. But that doesn't explain why other species would react in this way. Another possible reason is that for species under a yellow sun, red and yellow stand out more than blue or green, due to the way our eyes evolved. Again, this wouldn't explain species evolving under a blue star. Unless of course, C. A. S. T. doesn't have any. These organizations do seem to have an unhealthy bias towards bipedal humanoid species. As to why they keep producing red uniforms, even though they seem to get people killed: 1. once the news got out, the price of red dye plummeted. One or two subunits per metre isn't much unless you're taking billions of items, then it's a massive price difference. And white needs replacing more often to look impressive. 2. Somebody ordered a few billion units to get advantage of bulk rates and management won't sanction more funds until they've all been used. 3. The Red Dye Manufacturers' lobby group and the Union of Red Dye Workers have unusually issued a joint statement saying they'll make times interesting for any administration that stops red uniforms, even though the equipment manufacturers making the machines used to process the red dyes for uniforms have issued a statement saying that their products can be easily adjusted to produce different hues and no additional training is required. Strangely, the outer ~~Federation~~, ahem, *Conjoined Alliance* planet, whose only export is a very specific, and hitherto popular, red dye has not been heard from. [Answer] Because red clothes are viewed as 'cool' or 'sexy'. The fact that the surgeon general puts a label on the tag claiming that they are bad for your health only seems to encourage today's youth to wear red. The fact that you must be 18 or older to even buy a red-shirt doesn't stop high-schoolers from wearing red underneath their normal school uniforms. Besides, how bad can it be? After all I can stop wearing red any time I want. [Answer] Bureaucracy for the win; they have the gear already and it cost so very much... This is far from the first case in which an organisation has continued a questionable process or practice because the materials for that practice are already in their inventory and they would rather use that inventory than having to write it off, at a drastic lose. So until the, massively over-ordered, stockpile of "red-wear" is depleted the higher echelon are stuck with it. Sorry just saw the word "produce" so make that until the massive and heavily over-ordered stockpile of Red Dye No. 4 is exhausted they have to keep making "red-wear" and people are stuck wearing it until it's all worn out. [Answer] This is simply a case of mixing cause and effect... The more dangerous jobs tend to have red shirts because (to quote Deadpool) then the baddies can't see you bleed. The lethality of the job is not actually hinged upon the color of the clothes, if they changed security to *green*, then simply *green* would be the new *red*. [Answer] The red shirts are assigned to the departments where they put all the people who are too clever by half. Everyone knows the leaders of C.A.S.T. give ~~due consideration to all aspects~~  ~~think things through~~ make decisions with their ~~heads up their~~ advisers in close conference. When someone has the ~~intelligence and insight~~ temerity to question those decisions, well... his or her uniform color changes. [Answer] It's common knowledge that red makes things go faster, as [documented on TVTropes](http://tvtropes.org/pmwiki/pmwiki.php/Main/RedOnesGoFaster). Individuals wearing red can get to where they need to be faster; they can accomplish their tasks faster; they can eat faster; they can get their medically mandated relaxation done faster, meaning they can get back to work sooner. It would be irresponsible of the C.A.S.T organization to deprive its members of such a boost, allowing other, less benevolent organizations to leapfrog them and threaten the safety of C.A.S.T.'s members and any poor, defenseless, civilizations not yet assimilated welcomed into C.A.S.T.'s friendly arms. Alright, so the speed boost might also make individuals a little clumsier, tripping more often and then falling a little faster, hitting the ground a little harder than their bodies can handle. Or they might punch the Giant Space Amoeba of the Week a little too fast, shattering all the bones in their arm and leaving them a tad vulnerable to the Amoeba. For those individuals who have earned a bit more relaxation time, who require more precision for there tasks, or who do more thinking than physical activities, i.e. the Commanders, the Medics, the Scientists, and the Engineers, they can be issued uniforms of other colors. But for the disposable highly valued majority? High speed, high efficiency RED! [Answer] ### Karma The C.A.S.T. believe that it is better to have many parts lives with significance than a few long lives where they are rarely on camera seen and without lines heard. They believe that the next part life will pay better and provide more professional satisfaction be more enriching. If the C.A.S.T. were to wear a safer color, they would have to stay in their insignificant parts lives longer. They wouldn't be able to go on to the glory they deserve. And death scenes pay better. [Answer] Simple, we call it risk management. Lets assume that the statistical increase of risk is proven, that is its not correlated but directly involved by the color of people's shirts. So if 1 person in 20 dies in an occupation wearing anything other than red, if they are all wearing red then 10 out of the 20 would die instead. That is a 10 fold increase. But classifying people in a large organization such as C.A.S.T. by their discipline is important especially in emergency situations. And what better way to make their discipline known quickly than to just simply give them different colored shirts? So we come to the question, which colors should we use? We do not want too many colors because if they start blending into each other then we may get confusion when trying to determine an individual's discipline in the shortest time frame possible, such as in emergencies. Let's say that statistically using more colors then the 7 colors in a rainbow would cause enough confusion. So if we try to cut off red from the options we are left with only 6 possible colors to designate disciplines, which if you ask me is too small. In a small team of 6 people or less with each member having distinct specialties you will get way with it. But what happens if you have more? You have to merge disciplines and make each category broader. Which forces one of two things to happen, either every individual with a specific color is trained in the whole generalized discipline, or you add extra complications to color scheme. And we are already limited from a previous assumption. So now each member must be trained in more disciplines to fit the generalized discipline represented by their shirt color. So now that we have that set up, lets say we add red back into the options. We get 7 choices instead of 6. That reduces the amount each major discipline needs to cover for every individual wearing that color to fit a task that requires the discipline. But red is a 10x increase in risk, so who gets the red color? Simple, the discipline that is less prone to death, such as reserves back in secured home worlds. Using previous example but with bigger numbers, lets say we have two disciplines. One has a risk of 100 people dying for every 1000, and the other is a measly 5 for every 1000. Who should get the red shirts? Give it to the first discipline and you'll have everyone dead when they are needed. But give it to the second one and you will still have people left alive to train the next group. Advantage of C.A.S.T. is that they are so big that extra man power is not a problem, especially when they have so much control over information as to redact their author's statements. [Answer] Red uniforms are given awarded to the biggest troublemakers bravest patriots as a way to get rid of reward them for years of bucking the party line faithful service. [Answer] If they are "some of the smartest people in the known universe" then they surely know the difference between correlation and causation. They might have even made experiments with giving security troops (and only security troops) green shirts, and observed that now green shirts "produced" the most casualties. On days where more ice-cream is sold, more people drown. Does this means that ice-cream causes drowning? Or might it be, that when the wetter is hot, more people eat ice-cream, but also more people go swimming? So, as it doesn't matter, and as people are already used to the color red, they just keep it out of sheer cultural inertia. Maybe they like cultural inertia, and don't like the idea of renaming or recoloring something every ten years or so to become "the new black". [Answer] Tradition. We wear red Shirts and we will wear red Shirts. In any military circumstances (army or (space) navy), tradition is very important and not to be changed just because a few additional deaths. [Answer] You might think you're tough, but you're not tough until you've worn the Red Uniform. It's the emblem I've borne for the past 20 years. We're the baddest of the bad. You need something done, ask a Red Uni. We get in there first, before anyone knows what hit them, and we're the last ones out, cleaning up all the mess you sissies leave behind. Sure there are some who can't cut the mettle-- space is a harsh mistress. They're losers, imposters who weren't worthy to bear the Red, but still, we have undying respect and loyalty for those who went down beside us. Now if you'll excuse me I have some ass to kick. And I'm bringing my rolodex and a bic pen. [Answer] There is a subset of Trek fans who refer to the expendable dying shirt color as "Gold Shirts" because they started in the TNG era when the original Security (Red) and Command (Gold) swapped colors. Others (such as reviewer SFDebris) will refer to a Red Shirt in TOS and a Gold Shirt in TNG/DS9/Voy with the same narrative expectation (that is to die). The term Red Shirt is more famous out of the Star Trek community, because the term predates TNG (the color swap was partially because the term being used so much). This of course neglects the films Star Trek 2-7 in which Starfleet went through a uniform phase where every department wore a red outfit with a color and cuff color denoting specific department. Edit to add comment additions: Basically, what was said elsewhere: It's correlation does not equal causation. The red has nothing to do with the causalities but the fact that its the department color of the primary fighting force, and thus more likely to be in dangerous situations. The color being bright and noticable would only work for humans... if the aliens see in different spectrum or have trouble with red spectrum, the idea of the forces being brightly colored is moot. In addition, given that in all Television series, Engineering and Security wear the same colors, it might be a bit of a coded warning to other personnel to pay attention to this person, because they are probably doing something dangerous (i.e. Shooting a Honorable Warrior Alien that has boarded the ship or tampering with a plasma conduit that has gone faulty... neither of which you want civvies or your medical/science/command staff anywhere near). Modern Aircraft carriers employ red shirts to handle ordinance loading for this reason. If you see one running, don't ask, just follow and keep up. [Answer] ## It's in the dye It's very simple. There is a single red dye is used universally for all red fabric across the whole of CAST. This dye was synthesised from an organic molecule found in a specific parasitic worm, and has become widely used because it is easy and cheap to replicate in large quantities. Unfortunately, this specific dye has a property that is heretofore unknown: when absorbed into the body via the skin, it can trigger a neurological response that inhibits the individual's sense of danger. Those wearing red become very slightly more willing to take risks. The more you wear it, the more likely you are put yourself into a position that will get you killed. Why would the original parasitic worm have a molecule that can do this... maybe it has a life cycle similar to [Toxoplasma gondii](https://arstechnica.co.uk/science/2016/11/a-tiny-brain-parasite-seems-to-make-rodents-braver-and-it-likes-humans-too/). It just so happens that the same molecule that helps the parasite do brain control also happens to be a perfect red fabric dye. Well... perfect, except for one tiny detail... [edit] As for why the continue wearing red clothes despite the increased death rate, the reason is simple: The same neurological response that makes you more prone to getting killed also makes you a better soldier. You respond to dangerous situations with more bravery and selflessness, and ultimately improve the chances for everyone else. There are more deaths among wearers of red, but also more medals and more heroes. [Answer] The idea that the color red is the primary cause for people being killed is a false assumption. Actually it is the occupation those people have that is the primary reason for their job not being safe. The EDIT ( the Earth Directorate for Intelligence Transformative analytics ), a brilliant board of real scientists, discovers this by replacing the color red with pink on certain away missions thereby showing that the danger of death migrates with that color. The CAST thereby replaces its scientists with real scientists from the EDIT and efforts are being made for ensuring the poor Redshirts survival. [Answer] Other factions know wearing red is dangerous so an organisation claiming to come in piece with red shirted members are not foreseeing any kind of danger and must not be a threat. ]