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Math Science

Mathematician: Is Our Universe a Simulation? 745

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."
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Mathematician: Is Our Universe a Simulation?

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  • by WilliamGeorge ( 816305 ) on Sunday February 16, 2014 @05:09PM (#46261507)

    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.

  • Re:Simulation or not (Score:5, Interesting)

    by quantaman ( 517394 ) on Sunday February 16, 2014 @05:17PM (#46261577)

    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.

  • by Anonymous Coward on Sunday February 16, 2014 @05:18PM (#46261593)

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

  • by aussersterne ( 212916 ) on Sunday February 16, 2014 @05:21PM (#46261603) Homepage

    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?

  • by MobyDisk ( 75490 ) on Sunday February 16, 2014 @05:38PM (#46261719) Homepage

    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?

  • by Aighearach ( 97333 ) on Sunday February 16, 2014 @06:03PM (#46261915) Homepage

    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.

  • by bmo ( 77928 ) on Sunday February 16, 2014 @06:10PM (#46261979)


    What now, motherfucker?


  • by Paul Fernhout ( 109597 ) on Sunday February 16, 2014 @07:21PM (#46262481) Homepage

    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). [] [] [] []

    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

  • by catmistake ( 814204 ) on Monday February 17, 2014 @05:23AM (#46265211) Journal

    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.

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