6 ms·
Do we live in a computer simulation? UW researchers say idea can be tested
- ISL 14y agoArXiv paper: http://arxiv.org/abs/1210.1847 http://arxiv.org/abs/1210.1847 This work attempts to draw out the presence of a simulation by looking for tiny violations of known/expected symmetries, which is always worth doing. We should note, however, that an excellent simulation could exactly cover its tracks, lest the underlying architecture cause unintended artifacts. From a CS perspective, the simulation's developer might create unit tests that guarantee the preservation of symmetries. A theorist who develops an experimental test that could prove we do not live in a simulation should be lauded. There are experimentalists (like me) just waiting for such guidance. John Bell's theorem [1] was/is a shining guidestar for physics. [1] http://en.wikipedia.org/wiki/Bells_theorem http://en.wikipedia.org/wiki/Bells_theorem
- coopdog 14y agoI think they're assuming that the simulators don't have infinite resources, so eventually we'll find a 'wall' in the simulation. "With finite resources at their disposal, our descendants will likely make use of effective theory methods, as is done today, to simulate every-increasing complexity, by, for instance, using meshes that adapt to the relevant physical length scales, or by using fluid dynamics to determine the behavior of fluids, which are constrained to rigorously reproduce the fundamental laws of nature." It's possible that if we were simulated, the simulators aren't actually trying to hide the nature of our universe from us. It's also possible even though the simulation started with a 'simple' framework that they could have hidden better if desired, that by becoming a self aware information system we can no longer be switched off / restarted without violating their ethical constraints. So it's possible that the limits a simulation actually are detectable. Of course as someone said, if the simulators were actively monitoring your thoughts with the intent of stopping you from finding the boundaries then there truly would be nothing you could do.
- huseyinyilmaz 14y agoOur decedents might have a certain level of technological advancement that Moore's law works a lot faster for them. If it is above a certain level, we would not fast enough to detect that limit.
- seanica 14y ago> A theorist who develops an experimental test that could prove we do not live in a simulation should be lauded. That sounds like they would be proving a negative, which is impossible to do.
- alanctgardner2 14y agoThat's a pretty silly statement. Surely you can prove that 1+1!=3, which is the negative of 1+1=3. You can also prove that pi is not a rational number, 1/2 is not an integer, etc. There's a post on the front page about attempting to prove P!=NP.
- deleted 14y ago[deleted]
- evincarofautumn 14y agoThe typical formulations of all of those proofs are by contradiction, though—so it may be worth distinguishing “prove” from “demonstrate by proof”.
- alanctgardner2 14y agoIs there a distinction between proving and demonstrating by proof? I did a quick search (I'm hardly a mathematician), to quote Wikipedia: > a proof must demonstrate that a statement is always true It would seem that, if you can demonstrate a statement is true for a given logic, that is proof. Contradiction and exhaustion (which is a bit more controversial, I think), while less tidy than one might expect, are valid techniques for showing that a statement is always true, and therefore are valid ways to construct a proof. Note: I encourage any and all maths professors to come and tell me off if I'm way off base.
- ISL 14y agoI am wearing only two socks. Both socks are black. Is it impossible for me to prove that I'm not wearing red socks?
- 14y ago
- electrograv 14y agoThe scientific paper deals with "the hypothesis that the observed universe is a numerical simulation performed on a cubic space-time lattice or grid". Just because the universe may operate with computer-like regularity and grid-like data structures does not mean "the universe is a computer simulation." At best it means the fundamental laws of physics are "computer-like". Whether "resembles a computer simulation" equals "is a computer simulation" is a metaphysical/philosophical question. Finding uncanny resemblance between our own reasoning concepts and the universe is not new - and this uncanny mirroring between abstract mathematical concepts and the laws of physics has been known for quite some time. It's a mystery, not an answer. See: "The Unreasonable Effectiveness of Mathematics in the Natural Sciences" by Eugene Wigner: http://www.dartmouth.edu/~matc/MathDrama/reading/Wigner.html http://www.dartmouth.edu/~matc/MathDrama/reading/Wigner.html
- napoleond 14y agoIndeed. And conversely, proving that the observed universe does not operate on a cubic space-time lattice would not prove that it is not a simulation of some sort--it would merely prove that it is not a simulation of that sort.
- caseysoftware 14y agoAlso.. if we are a simulation, wouldn't those running the simulation see what we're doing and supply us with the correct results that we would expect? They could just hardcode it..
- spindritf 14y agoMaybe they're not so bright or careful? Or maybe it's all happening too fast for them? http://lesswrong.com/lw/qk/that_alien_message/ http://lesswrong.com/lw/qk/that_alien_message/
- neumann_alfred 14y agoThat was the most fascinating thing I barely understood a word of that I read in a long time. Thanks!
- benjohnson 14y agoIf the universe is a simulation, what's to stop the simulation from recognizing that it's being tested and dedicating more resources to making the test result indicate that there is no simulation going on.
- EthanHeilman 14y agoThat sounds a lot like a measurement having an effect. http://en.wikipedia.org/wiki/Wave_function_collapse http://en.wikipedia.org/wiki/Wave_function_collapse
- dhughes 14y agoIsaac Asimov's 'The Last Question' answers that.
- mayanksinghal 14y agoI feel stupid that I absolutely love this story but have no idea what you are you referring to.
- dhughes 14y agoMaybe we are a computer simulation but maybe we are the computer!
- ComputerGuru 14y agoThe Last Question is one of my most favorite short stories, and unless I'm completely missing something, has nothing to do with simulation.
- shmerl 14y agoStanislaw Lem actually has a story precisely on this subject.
- deleted 14y ago[deleted]
- gojomo 14y agoMe layman's hunch is that we would only be able to test this if either (a) the simulation is flawed, or (b) the simulation designer chooses to give us hints (perhaps more subtle than 'miracles' or revelatory visions).
- Bogosaurus 14y agoQuantum Bogosort http://en.wikipedia.org/wiki/Bogosort http://en.wikipedia.org/wiki/Bogosort
- oes0 14y agoThe mystery between DMT and brain chemistry is also a valid area to understand such an idea. DMT is a naturally occurring substance that's in the human body, animals and various plants. The mystery is that it is almost identical to serotonin and tryptophan. But it is not like any other drug. It's almost unfair to call it a drug. Under its effects, reality looks radically different. You can see the math and inherent aspects within physical reality. With your eyes closed, the experience is even more profound. Of course, it's likely just an artificial experience, a chemical delusion. But it an amazingly mystical experience, that can be duplicated over and over. It's unlike any other psychedelic and is the only scientific way I'm aware of that induces a "real" mystical/spiritual experience.
- freshhawk 14y agoThis strikes me as equivalent to researchers hundreds of years ago saying "well if our universe is a clockwork simulation then we should be able to detect the gears turning by this method". Certainly interesting ... I'm not sure that we could currently understand a single principle of a system capable of simulating our universe.
- azakai 14y agoWell yes, it is equivalent. And they looked more and more carefully, and never found tiny clockwork gears, so that was not supported by the evidence. What they did find were abstract, mechanical laws of physics.
- freshhawk 14y agoA more apt analogy would have been testing for a specific number of gears with a specific number of teeth in a specific configuration. Choosing very specific hypotheses purely based on your ability to falsify it and no other supporting theory or evidence seems like a low reward strategy. I'm certainly not trying to argue against pure research in any way.
- rymith 14y agoWhat would be the purpose of a simulation with so much pain and suffering. Where children get raped, flayed, abused, etc... And don't give me any of that matrix crap, that was only to make a flawed concept make just enough sense that you didn't fully think it through until the next bullet time scene. I'm certainly not on the outside paying for this. I have a degenerative bone disease that's caused me to have 6 major surgeries in 6 years. If this is a simulation, when I get out, I'm going to kill the son of a bitch that put me in here.
- nsxwolf 14y agoVery interesting that you can replace 'simulation' with 'God' and your statements are a perfect recitation of 'The Problem of Evil'. http://en.wikipedia.org/wiki/Problem_of_evil http://en.wikipedia.org/wiki/Problem_of_evil
- jlgreco 14y agoThe problem with applying that (very reasonable, in my opinion) argument to this discussion is that it invokes assumptions of benevolence, or even planning and/or intent. Those things are largely irrelevant to the question of simulation. There should be no implicit assumption that a simulation must have any sort of "deity" behind it. Nothing with intent, purpose, planning, ethics, etc. It seems much more reasonable to me that such a simulation, if it is in fact the case, 1) arose "naturally", whatever that may mean, and 2) does not care about us. This universe, simulated or otherwise, does not care about humans. Why should we assume the proposed simulation does?
- gliese1337 14y agoWell, the idea that the simulators care is the basis for the standard argument that we're probably in a simulation. After all, it's supposed to be posthumans running simulations of their evolutionary ancestors. I don't know why they would do that, but given that premise, why run simulations of your ancestors if you don't care about your ancestors? Of course, that provides another answer to the problem of pain- that this is how it was the first time 'round, and they want the simulation to be accurate.
- shmerl 14y agoThis idea is way older. Various mystics already envisioned the metaphysical structure of the world in such way (i.e. creation of reality through symbolic transformation - computational idea similar to Markov's algorithms). See for example Taam Eytzo by R. Pinchas Eliyahu Horowitz of Vilna (18th century philosopher and mystic): http://www.hebrewbooks.org/21931 http://www.hebrewbooks.org/21931 There are a few papers published on this subject: http://www.tandfonline.com/doi/abs/10.1080/01445340.2010.506106 http://www.tandfonline.com/doi/abs/10.1080/01445340.2010.506... http://aleph.nli.org.il/F?func=find-b&request=000509568&find_code=SYS&local_base=RMB01 http://aleph.nli.org.il/F?func=find-b&request=000509568&...
- ck2 14y agoI thought the more plausible theory is we are a projection of another dimension. But pain and suffering seems far too real and horrible for any of this to be fake.
- alexmat 14y agoHow is "fake" pain different from real pain? From my understanding, our neural correlate of consciousness is in fact a transparent self model simulation our brain is running, so in that sense all conscious pain experience is "fake". Or do you mean something else?
- empthought 14y agoThe most plausible theory is that we will go extinct before reaching a "post-human" phase.
- mynameishere 14y agoHas any smart 13-year-old not come up with the notion that the world might be a computer simulation?
- ComputerGuru 14y agoDoes it matter? Think about a simulation in a game on your PC. Nothing in that game actually exists outside the simulation. i.e. as far as anyone/anything in the simulation is concerned, the simulation is real. You cannot leave the simulation. You cannot end the simulation. There's nothing unreal about the simulation for anyone in it.
- TeMPOraL 14y agoIt does. If the simulation is buggy, we could hack it and "get out of the box" :). See also: http://lesswrong.com/lw/qk/that_alien_message/ http://lesswrong.com/lw/qk/that_alien_message/
- majmun 14y agothis happens when you die, universe segfaults, or it continues running in hell, limbus or heaven. depends on where it lands. hell has 9 rings. goal is to end up in ring 0 . heaven
- exit 14y ago> You cannot leave the simulation. At any level of simulation we know that when we take time, it takes time in the reality that hosts us too. It's nice to know we'll always have that in common.
- jlgreco 14y agoThe idea seems to be, from within the simulation, detect artifacts of the simulation. Seems like a sensible enough proposal to me. (That doesn't mean I think they will succeed).
- ars 14y agoThis assumes that reality is simulated using a grid, and particles are either in that cube or that one. But that's not the only way to run a simulation - you can make the fundamental particles the building pieces and simulate them - they can move anywhere they want, in any direction, they don't live in a grid. The only thing that matters is their relationship to the particles near them. Which follows very nicely from relativity which shows that there is no absolute coordinate system, or absolute energy, only relative distances and relative energy differences. i.e. like the difference between polar coordinates and rectilinear ones.
- TeMPOraL 14y agoAlso the simulation doesn't really even have to involve particles. Stephen Wolfram did some interesting writing on concept of our reality / laws of physics emerging from simple computational systems like cellular automaton [0]. Also Eliezer had some interesting points about how a continous interpretation of causal networks gives rise to some concepts we recognize from physics, like space, time and the speed of light binding them together [1]. [0] - http://www.wolframscience.com/nksonline/toc.html http://www.wolframscience.com/nksonline/toc.html [1] - http://lesswrong.com/lw/fok/causal_universes/ http://lesswrong.com/lw/fok/causal_universes/
- andrewflnr 14y agoNo it can't. The simulation hypothesis will never be testable. All our assumptions about the hypothetical computers our universe runs on are based on things as they are in this universe. We have no basis at all for applying these assumptions to the host universe. We don't know if the simulation runs on a discrete computer, a finite computer, or whether it resembles a Turing machine in any way. We don't know what kind of physical limits there are on computation, or to what extent those are even recognizable concepts, and that's just a few highlights. We have no idea what it might be like up there, or what can be done. And don't tell me about "likely", you have no data worth mentioning, in particular about "likely" physics or "likely" motivations of simulators.
- firlefans 14y agoWhy do smart people love to debate the most implausible nonsense? Time travel through singularities anyone?
- the_cat_kittles 14y agoWhile I don't know if it's actually deserving of the title "implausible nonsense", I think its important to remember that stupid is as stupid does, and same goes for smart. Someone isn't smart because they have the trappings of intelligence, its because they did something smart.
- firlefans 14y ago"its because they did something smart" So intelligence == 'achievement'? That makes no sense. As for nonsense, ok I'll retract that, it is an interesting but highly implausible topic that gets a large amount of discussion relative to it's likelihood. It's actually just another way of phrasing "Does God exist?" If there was a computer (God) simulating this universe and controlling it, then it'd require a host universe for itself to exist, and it's complexity has to be greater than what it is simulating. Therefore it is less likely, and not by an insignificant amount.
- the_cat_kittles 14y agoI guess its true that you can't just equate intelligence with achievement. In my own life, I think I've increasingly used achievement where I used to use intelligence to gauge how 'smart' someone is. That comment was also trying to get at the annoyingly pervasive belief people seem to have that you must be smart because you are a mathematician, say. As an example, novices might think someone is good at basketball based on how they look on the court- but you wouldn't say someone is good unless they actually had a big positive effect on how often their team won. In general, I guess when I say smart, I mean "good" in some abstract sense.
- nnq 14y agofood for though (mostly offtopic): what if most simulations are actually nurseries, run by our descendants as an alternative to mostly random procreation? ...I imagine that in a very distant and complex hypothetical future, the only way that super-intelligent beings could reproduce in a way that the offspring would truly be similar enough to their parents, so that they could feel empathy one towards another would be either by: (1) clone and mutate an existing individual (think mind-cloning, like software copying) and mutate, and (2) create "children from scratch" and raise them, for at least a few "eons" in successive simulations of their parents or ancestors pasts (any other alternative, I'd imagine, in a post-singularity world evolving incredibly fast, would result in offspring so different from their parents that it would make empathy and the existence of a shared culture with shared artistic and aesthetic values impossible...) ...maybe we're just "babies" in the first level of a simulated nursery, waiting to complete the stages to "adulthood" in world of unbound, "software like", intelligent beings :) EDIT+: ...just realized that this could be made up into pseudo-scientific pseudo-theory of reincarnation (which I don't believe in, but I find it interesting) ...if any buddhist or hinduist mystic reads this and takes my idea and does something intersting with it, please give me credit as original author :)
- frozenport 14y agoarxiv is not a peer reviewed journal
- GotAnyMegadeth 14y agoImagine, in the far future, you were able to to create a simulation that was so advanced that it could accurately recreate everything that has happened in the universe so far, so that it was an exact replica of history. Also, that there is a way which you can determine whether you are in a simulation or not. Assuming you are in the real universe, if you make this measurement, it will show false, however when your simulation reaches that point in history, the result would show up true, and reality and simulation would diverge. The only way to stop this would be to make a more advanced simulation that could not be detected with any method, or to have some part of your simulation check for when this test is made, and spoof the result...
- codex 14y agoThe assumptions in this paper are quite weak. It's like testing whether or not your code is running in a virtual machine. It can be done, but only if the virtual machine authors have made some glaring mistake. Yes, computation is finite, but that doesn't mean that the authors of the simulation can't use more resources than usual simulating your test of the simulation. Not all parts of the simulation need to run at the same level of detail.