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Mathematician: Is Our Universe a Simulation?

Hugh Pickens DOT Com writes "Mathematician Edward Frenkel writes in the NYT that one fanciful possibility that explains why mathematics seems to permeate our universe is that we live in a computer simulation based on the laws of mathematics — not in what we commonly take to be the real world. According to this theory, some highly advanced computer programmer of the future has devised this simulation, and we are unknowingly part of it. Thus when we discover a mathematical truth, we are simply discovering aspects of the code that the programmer used. This may strike you as very unlikely writes Frenkel but physicists have been creating their own computer simulations of the forces of nature for years — on a tiny scale, the size of an atomic nucleus. They use a three-dimensional grid to model a little chunk of the universe; then they run the program to see what happens. 'Oxford philosopher Nick Bostrom has argued that we are more likely to be in such a simulation than not,' writes Frenkel. 'If such simulations are possible in theory, he reasons, then eventually humans will create them — presumably many of them. If this is so, in time there will be many more simulated worlds than nonsimulated ones. Statistically speaking, therefore, we are more likely to be living in a simulated world than the real one.' The question now becomes is there any way to empirically test this hypothesis and the answer surprisingly is yes. In a recent paper, 'Constraints on the Universe as a Numerical Simulation,' the physicists Silas R. Beane, Zohreh Davoudi and Martin J. Savage outline a possible method for detecting that our world is actually a computer simulation (PDF). Savage and his colleagues assume that any future simulators would use some of the same techniques current scientists use to run simulations, with the same constraints. The future simulators, Savage indicated, would map their universe on a mathematical lattice or grid, consisting of points and lines. But computer simulations generate slight but distinctive anomalies — certain kinds of asymmetries and they suggest that a closer look at cosmic rays may reveal similar asymmetries. If so, this would indicate that we might — just might — ourselves be in someone else's computer simulation."

36 of 745 comments (clear)

  1. A looping simulation, apparently by fascismforthepeople · · Score: 5, Funny

    That paper is from November 2012. We should have been able to catch it a little bit earlier than this. That, or the person running the simulation missed an important loop bug.

    1. Re: A looping simulation, apparently by NoEvidenZ · · Score: 3, Informative

      They did catch this years ago. http://m.slashdot.org/story/17...

    2. Re:A looping simulation, apparently by Aighearach · · Score: 5, Interesting

      Indeed. He doesn't notice that math is a set of abstractions that humans use to model their environment. It would be a pretty awful model if he didn't look out and see those patterns.

      It is like a glass maker looking in a mirror and deciding that glass has humans inside. No, really, you should know this stuff.

      And if he sees so many patterns, he should probably look at all the warts, too. "Natural" numbers are natural to humans, but those aren't the numbers/proportions nature uses. If math was really modeling the universe well, we would have whole numbers for constants: e, c, k, pi. Math is very useful, and at human scale we mostly don't notice the lack of symmetry. The different things in the universe that we model with math are often symmetrical to each other. But the math is not perfectly symmetrical to the individual components in nature.

    3. Re:A looping simulation, apparently by weilawei · · Score: 4, Funny

      e^(i*(1/2)*2*piiiii)-(0.19915)=0.80085

      What now, Mr. Pimp?

    4. Re:A looping simulation, apparently by Cryacin · · Score: 4, Funny

      Do you see what happens when you let theoretical physicists hang around with the chemistry majors? Smoking crack and watching the matrix does not make for scientific advancement, nosiree.

      --
      Science advances one funeral at a time- Max Planck
    5. Re:A looping simulation, apparently by icebike · · Score: 3, Funny

      e^(i*pi)+1=0

      Isn't that answer supposed to be 42?

      --
      Sig Battery depleted. Reverting to safe mode.
    6. Re:A looping simulation, apparently by Aristos+Mazer · · Score: 3, Funny

      Sometimes when they modify the Matrix, you get a sense of deja vu.

    7. Re:A looping simulation, apparently by PopeRatzo · · Score: 5, Funny

      Um, speaking of cocks, if the universe really is a simulation, could I get a re-roll, please?

      --
      You are welcome on my lawn.
    8. Re: A looping simulation, apparently by AcidPenguin9873 · · Score: 3, Informative

      Nah, you've got a couple problems in your example.

      First, your exact real-world problem doesn't make sense with a divisor that is less than one, which is how you get close to zero. Five dollars divided into 0.5 parts? What does that even mean?

      Now let's flip around your real world example to something that makes sense. Five dollars divided into how many parts, where each part gets $0.50? 5/0.50 = 10 parts. Five dollars divided into how many parts, where each part gets 0.0000001? 50000000. Five dollars divided into how many parts, where each part gets 0? Infinity.

    9. Re: A looping simulation, apparently by hawkinspeter · · Score: 3, Informative

      You're partly right in that we can define divide-by-zero how we want, but there are serious problems when it is defined (e.g. as infinity) as it leads to a huge amount of inconsistencies in other areas. The simplest example is the typical proof that 1 = 2 which uses a divide-by-zero to lead to absurdity. If you want consistent numbers, then division by zero needs to be undefined.

      --
      You're a temporary arrangement of matter sliding towards oblivion in a cold, uncaring universe
  2. Some possible ways by Shalian · · Score: 5, Funny

    Some possible ways to determine if we're living in a simulation:

    Look for signs of optimizations/short cuts in the simulation:
    Is there a maximum speed?
    Is there a minimum size?
    Is there a limit as to determining an object's position and momentum?
    etc...

    1. Re:Some possible ways by StripedCow · · Score: 5, Funny

      Another idea: try to generate an overflow, or division by zero.

      What could possibly go wrong?

      --
      If Pandora's box is destined to be opened, *I* want to be the one to open it.
    2. Re:Some possible ways by WilliamGeorge · · Score: 3, Interesting

      The behavior of light in the 2 slit experiment might be an example of this.

      I find it hilarious, though, that people are open to this possibility but so hostile to the idea of creationism. Both amount to the same sort of situation: a created universe, rather than one devoid of any design or purpose.

      --
      William George
    3. Re:Some possible ways by Anonymous Coward · · Score: 5, Interesting

      I would think people aren't hostile towards creationism as an idea, but more towards the people who tout it as the undeniable truth.

    4. Re:Some possible ways by Sique · · Score: 4, Funny

      I'm going to sign a petition that division by zero should be permitted if human lives are in danger.

      --
      .sig: Sique *sigh*
    5. Re:Some possible ways by ericloewe · · Score: 3, Funny

      Just work in C, then you can call it a singularity and do stuff with it.

    6. Re:Some possible ways by Opportunist · · Score: 4, Funny

      Not to mention that he's a bit of an antisocial asshole. He kicked out Adam and Eve after putting the trees there (as an omnipotent being he could've put them anywhere) and then punishing them for using them (as an omniscient being he must have known that this will happen). Not to mention that I'd get into trouble if I tried to flush down a failed experiment.

      And I bet he never had any kind of approval from some ethic commission for his human experiments.

      If I did a fraction of what he committed on humanity I'd be hunted down and dragged to Den Hague, then locked up with the key being thrown away. But he gets praise and worship.

      Corporations would kill to get a PR department like that.

      --
      We used to have a Bill of Rights. Now, with the rights gone, all we have left is the bill.
    7. Re: Some possible ways by Hognoxious · · Score: 5, Funny

      He tried that but the developer wouldn't follow the specs and had to be cast out.

      --
      Confucius say, "Find worm in apple - bad. Find half a worm - worse."
    8. Re:Some possible ways by Sabriel · · Score: 3

      Yeah, but when was the last time a bunch of string physicists burnt someone at the stake or stoned them to death?

    9. Re:Some possible ways by mrprogrammerman · · Score: 3, Informative

      I know you're trying to be funny but let's consider what the Bible says. First omnipotence. Briefly 1 John 4:8 tells us God is love and James 1:13 tells us he doesn't put the tree there to cause them to fail. As a loving parent expected the obedience of his human children (Rev 4:11).

      Now omniscience. Though he has the ability to exercise foreknowledge. He selectively uses it. See the examples at Genesis 11:5-8 and Ge 18:20-22 of occasions where he didn't exercise his foreknowledge but chose to make a decision based upon the current situation. Think about it this way. You can use your web browser to go to slashdot. But the fact that you can visit slashdot doesn't mean you will do so. You have to first open your web browser then type in the url. Likewise, God has the ability to foreknow events, but the Bible shows that he makes selective and discretionary use of that ability.

      His exercise of foreknowledge is going to harmonize with his qualities. And as a God of love he wouldn't set before Adam/Eve something that was unattainable. As humans we would think it would be cruel and hypocritical to hold out something to somebody that was unattainable for them. Read Mt 7:7-11. Jesus shows his Father’s views it the same way.

      And about the PR department. It's actually really Satan's PR dept (1 John 5:19). That's why most religion makes a mockery out of him (2 Corinthians 4:4). He still wants all people to learn the truth for themselves (1 Timothy 2:3-4). In fact he's personally looking for people who want to discover the truth (John 6:44, 2 Chronicles 16:9).

    10. Re:Some possible ways by turkeyfish · · Score: 4, Funny

      With NSF grants being as competitive as they are these days, don't start giving them ideas.

    11. Re:Some possible ways by Lisandro · · Score: 3, Informative

      Division by zero is mathematically undefineable.

      If A * B = C and C / B = A, you can't have B being zero without C being also zero (in which case the equation is valid for all values of A, a.k.a undefined). For every other value of C the equation has no solution. The only reason IEEE defined division by zero as infinity was to make errors easier to handle.

  3. The Thirteen Floor by Anonymous Coward · · Score: 4, Informative

    http://www.imdb.com/title/tt0139809/

    This is old news mister slashdot.

  4. Future? by jcr · · Score: 5, Insightful

    According to this theory, some highly advanced computer programmer of the future has devised this simulation, and we are unknowingly part of it.

    Wouldn't he have to be a computer programmer of the present, if he wrote this simulation and we're in it RIGHT NOW?

    -jcr

    --
    The only title of honor that a tyrant can grant is "Enemy of the State."
  5. Pointless Because ... by TrollstonButterbeans · · Score: 4, Insightful

    What is the definition of "not a simulation".

    If I am in a simulation and it seems real to me, what is the opposite of this?

    --
    Priest: "Universe from nothing, no laws of physics, sped up time"+ huge discrepancies. Creationism? No. Big Bang Theory
  6. Flawed premise. by Anonymous Coward · · Score: 4, Insightful

    First: humans observed the universe.
    Next, humans invented mathematics to model these observations.
    Then, humans refined mathematics over time, to even better model these observations.
    Then, humans became surprised at how well their model fit the universe, seeming to have forgotten how hard they worked to make it so.
    Then, humans started coming with very silly ideas about the model actually being the reality it models.

    The inclination to have faith in something fanciful doesn't always come from the religious.

  7. Re:Simulation or not by quantaman · · Score: 4, Interesting

    I am not stressed out by the notion we might live in a simulation because it changes nothing about the fundemental questions about the nature of reality, it only changes the context in which we ask them. It does add a whole new layer of interesting questions to examine, but strip away the stimulation and you are left where you were before.

    Maybe, but if we are living in a simulation maybe the real world has characteristics that change the question.

    Maybe the real world has deities that are regularly and obviously involved with the running of the reality and our universe is the results of an experiment that says "what happens if there are no visible gods?"

    Or maybe they're mostly happily atheistic and they're wondering what would happen if people were given a more superstitious nature.

    Maybe they're energy beings wondering what would happen if you change the laws of physics to allow these massive fireballs they called stars to form, and we're some kind of weird phenomena that's popped up in the simulation. Our consciousness isn't really a feature of our universe but a flaw the simulation that they don't notice because in the real world consciousness is a phenomena that occurs everywhere and is easily explainable.

    If we are living in a simulation there's really not a lot we can assume about what's going on outside.

    --
    I stole this Sig
  8. Silly language games. by aussersterne · · Score: 5, Interesting

    For this to be true in even the most allegorical sense would require that we stretch the definitions of "computer" and "simulation" well beyond anything we currently understand and well beyond the bounds of our ability to be concise and specific about what the terms mean. Using these terms here is just mixing up apples and oranges.

    We might as well, in other words, say that our universe is a blender inside a giant appliance store, a stageplay inside a giant theatre district, a mildewing blow tickler inside a giant hoarder's garage mess, or anything else bearing the one of the rough relationships signal:carrier, content:form, fragment:whole, instance:structure, etc.

    I mean, what sort of computer are we talking about here?
    What is its nature, not just logically, but physically? Do we even know that we're speaking "physically"? Isn't this the scale at which such quantities break down?
    And doesn't our idea of computation and simulation require precisely that mathematical rules apply for these to be carried out in the first place?

    --
    STOP . AMERICA . NOW
  9. Statistical basis by CODiNE · · Score: 5, Insightful

    Many people dream every night. Statistically there would be many more dream worlds than real worlds. So therefore this world is more likely to be a dream world than a real world.

    --
    Cwm, fjord-bank glyphs vext quiz
  10. This explains quantum physics by MobyDisk · · Score: 5, Interesting

    Quantum physics seems to be the ultimate proof that the universe is a simulation.

    The universe, intuitively, seems to be analog and continuous. That "feels" right to us. But quantum physics shows that it is actually discrete. But that is exactly how computer simulations work! They use very small time scales to make things appear continuous. We know that below certain time scales, things are essentially random. This is consistent with a computer simulation. You can't accurately simulate something that happens in less time than one "frame" of time. There is a whole area of mathematics that deals with how to make simulations work accurately given the limitation of discrete time scales.

    The same happens with physical sizes. Below the Planck scale the universe starts to break-down and become random. This is exactly how things would work if the universe was using binary arithmetic. Suppose that every particle in the universe has a coordinate. You can represent it's position over a vast scale, but only with limited accuracy. The plank scale is that limit, and it indirectly tells us how many bits are in the coordinate field of each particle. When we try to measure the position of something accurately, we find that the position becomes random. And if you try to measure it's speed to more resolution than one "frame" of time, it becomes less accurate. Worse-yet: the only way we can measure the position or speed of a simulated particle is by comparing it to another simulated particule, which introduces yet more error. We are ultimately limited by the accuracy of the simulation.

    One side-benefit of this is that we have an awesome source of stastically predictable randomness. Quantum computers are actually using the randomness of the simulator to take advantage of cpu-cycles that are "outside" of our universe. Within the simulator, we can only build a computer that is so fast. But if we find a way to tap into the computing power of the simulator, like by using the side-effects of one of it's built-in functions, then we can compute a result faster than anything we can do ourselves. It is like calling into "native code" while we are running in the interpreted bytecode.

    Another indication that we are in a simulation is that quantum physics shows us that wave functions collapse when we observe them. That makes sense: why should the universal simulator waste time calculating quantities that are not currently being measured? Imagine a vast number of inputs, a vast number of calculations that produce outputs, and a smaller number of observers of those outputs. You can easily optimize away things that are not being observed. But we found a way to notice the side-effect of not calculating certain values. It's like a side-channel attack on an encryption algorithm. You can tell how many bits of a password are correct even without the output by seeing how long it took to calculate, or how much power the computer consumed. I wonder if the designers of the simulator didn't know that we could see these kinds of side-effects, or if they are too difficult to fix. Either way, we are seeing side-effects of some of the shortcuts and optimizations.

    Perhaps one day one of the programmers will look over at their printer and find a little note from someone way down here inside the simulation. If you could hack a few words outside of the system, what would they be?

    1. Re:This explains quantum physics by Hugh+Pickens+DOT+Com · · Score: 4, Funny

      Hello world

  11. Not very plausible by yesterdaystomorrow · · Score: 4, Insightful

    Mathematics, especially simulation, is actually a very weak approach to physical phenomena in themselves. It's good for human insight *about* the phenomena, but in most cases the equations are intractable and a simulation is miserably inefficient at getting the specifics right. A small molecule can assemble itself in picoseconds without mathematics, but a simulation takes a huge supercomputer run. If you'd like to simulate something bigger, you'll find that simulation scales very badly.

  12. Living in a simulation by fox171171 · · Score: 4, Funny

    It could explain that weird green diamond thing floating over my head.

  13. No better than religion by Powercntrl · · Score: 5, Insightful

    I find it hilarious, though, that people are open to this possibility but so hostile to the idea of creationism.

    If you ask me, it's the same shit in a different package. Throughout most of early history, man had a pretty bad understanding of scientific principles and "God made everything" was an answer that fit what was observable at the time. As advances in scientific understanding were made, we've come up with theories as to why we're here that are have a higher likelyhood of being true based on observations (the Big Bang, for example). It's also just as likely we were observing some advance's alien race's fireworks show that predated our known universe, but just because that fits the observation, does not mean it's true.

    For example, if I put you in a completely darkened room and you heard meowing, would you know for absolute certain that there was a cat in the room? It could've been a recording of a cat, a person making a meow noise or even a parrot that was trained to meow. You could've said that "I heard a cat, so there is a cat in the room." and it would've fit your observation, but it could still be entirely incorrect. Likewise, these scientists may believe "the universe is a simulation" fits their observations. Just remember, until you can turn on the lights and see for sure - all that meows may not be a cat.

    --

    ---
    DRM is like antifreeze, to the MPAA/RIAA it's sweet, to the consumers it's poison.
  14. Creating simulations and checkpointing them by Paul+Fernhout · · Score: 4, Interesting

    Great point. I was in a PhD program in Ecology and Evolution, and also have written several computers simulations, and I have known about Fredkin's "the universe is a simulation" ideas since the 1980s. As I said before in some Slashdot posts, if you are serious about scientific skepticism, you have to admit is is possible we live in a simulation that has only been running for 6000 (or whatever) simulated years, and was started either from a check pointed version or started from some hand-crafted parameters and data files. Creators of such hand-crafted environments might perhaps be assisted by guided evolutionary processes like used in our PlantStudio 3D software or EvoJazz musical software, where a user picks from a set of variations over and over again to craft something (and originally inspired by Richard Dawkins "Blind Watchmaker" software). Using such tools may muddy the waters of what a "generation" means though, and it also seems likely organisms evolved together to produce their complex interrelationships in ecological webs.

    In any case, the universe might be a simulation. It might even just be a game we stepped into for an afternoon, with artificial memories implanted as in some Star Trek Holodeck scenarios. And we may not know until it is over (if then, if our consciousness persists). And even then, how many levels of nesting and branching are they in a multiverse of universes? Maybe C.S. Lewis was right, when characters feel at the end of the Narnia novels that a better heaven even closer to "God" somehow remains "ever inward, ever upward"? Still, does God have a God? And so on? If so, do they all agree on what morality should be in a consistent way? Or is it just turtles some or all the way up and we need to make a morality that promotes life and community? Or is it just exactly the way some specific version of the Christian Bible say, and the fossil record and geological record is a test of faith?

    Anyway, I hope considering the universe is a simulation helps more people move beyond a purely materialistic and "scientistic" view of the universe. There are so many interesting questions ignored, denied, or belittled by "materialistic scientism" (to use Charles Tart's phrasing).
    http://en.wikipedia.org/wiki/S...
    http://en.wikipedia.org/wiki/S...
    http://en.wikipedia.org/wiki/M...
    http://www.noetic.org/search/?...

    All that said, on a practical basis we can see evolutionary processes happening all around us (like with the flu virus mutating every year or bacteria become antibiotic resistant over time). As I said above, even if the universe was designed and only running for 6000 simulated years, evolutionary processes may have been be part of tools used to help make it. The fossil record may indeed have been placed there as a test of faith, and yet, would such a god be worthy of worship except out of fear? So, on a practical basis, we have to work with a lot of assumptions about a vast universe in age, extent, and complexity where evolutionary processes are important -- while at the same time honoring the mystery of it all, especially the mystery of consciousness we dwell in every second.

    The universe might also have been run for a long time up to a check point (like getting Linux set up nicely in VirtualBox) and then might just be run endlessly from that checkpoint. I'm not sure how "old" that would make this current run of the universe simulation then if the run was started only 6000 simulated years ago, but the check pointed version it was started from was let run for 14 billion simulated years before that?

    Anyway, just various interesting speculations on the great mystery which probably is way beyond human-brain-sized comprehending. It is the height of hubris to think we really can understand the universe of universes in

    --
    A 21st century issue: the irony of technologies of abundance in the hands of those still thinking in terms of scarcity.
    1. Re:Creating simulations and checkpointing them by catmistake · · Score: 3, Interesting

      Then, humans started coming with very silly ideas about the model actually being the reality it models.

      Humans aren't real. They are merely a hodge-podge of organs acting in concert which obey the standard medical model. Organs are simply groups of cells that act in concert, which obey the standard biological model. Cells are made of molecules which obey the standard organic chemical model. Molecules are merely structured atoms obeying the standard chemical model. Atoms are composed of bosons, fermions and hadrons, and hadrons are small clumps of quarks I think, and all these subatomics obey the standard nuclear model (aka the "Standard Model"). Bear in mind, all matter by volume is 99.999%+ empty space, and that none of the models I mentioned are empirically real; they are abstract. We just use them to help explain our observations, and they help the math come out neat. Thus, as humans are comprised of aggregates that are also comprised of more fundamental aggregates, etc., they're mostly just a convenience of language.