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Are we living in a computer simulation?

  1. Apr 28, 2006 #1
    Came upon the following article:

    Granted, there are some other approaches to the these metaphysical questions (string theory for instance) but... will it actually reveal the meaning of life or maybe finally discover GOD or refute his existence altogether?

    Exciting times are ahead, too bad we won't be here to observe them :)

    Also, Take note of the following article:

    There are many arguements against it:

    The last paper on string theory also proposed somthing similar (as a way of solving the unsolvable)

    On the other hand, it can also be argued for it:
    So what do you guys think?
    Last edited: Apr 28, 2006
  2. jcsd
  3. Apr 28, 2006 #2


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    No, it's just your imagination running away . . .

    This seems to more of a metaphysical or philosophical question, than a question of physics.
  4. Apr 28, 2006 #3
    Well but isn't String theory (or M theory) dealing with metaphysical questions? Wasn't Hawking writing about that thing that breathed life into the equations for them to have a universe there to describe? And isn't he a physicist?

    Besides, if metaphysics will be left alone, physics is pretty much pointless. We should answer the question "Why" first and foremost.
    Last edited: Apr 28, 2006
  5. Apr 28, 2006 #4
    Really? :cry:
  6. Apr 28, 2006 #5


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    It's a matter of being testable. In physics were do experiments to test theories. In metaphysics, one is left with speculation - which is tantamount to 'belief' in the absence of any evidence.

    Metaphysics - the system of principles underlying a particular study or subject : PHILOSOPHY !


    Physics deals with the 'observable', whereas metaphysics seemingly tries to answer whether or not one actually is observing, or if the 'observable' is real or a figment of one's mind. So metaphyiscs is a form of philosophy, not science.
  7. Apr 28, 2006 #6
    Exactly, but you know why metaphysics exists? Because if physics is all there is, then this life is by all accounts, BORING. We're born, have sex, eat, breath, get old and die (interpose anything in-between) and I feel it's quiet pointless (this whole journey) and death seems pointless as well so yes it's fun to speculate that whatever we observe around here is nothing compared to the way it really is otherwise it's really sad.
  8. Apr 28, 2006 #7
    How do you know metaphysics exists?
  9. Apr 29, 2006 #8


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    I have thought of the very possibility presented in this argument. It's a straightforward argument. It seems that the laws of physics help in building such a simulation. The speed of light limit, for instance, is very helpful. Suppose that the universe is stored in the form of a matrix of bits and that the computer generating the simulation updates this matrix every so often for every relevant change that takes place. Suppose there is only one individual in this simulation. Then the matrix need not represent the whole universe, only the immediate surrounds of the individual, and not necessarily to the atomic level. Instead, this matrix may have blank areas, the areas that are not relevant to the simulation. These areas are only filled whenever it is necessary, which only happens when the individual queries that area (this seems coherent with quantum mechanics for example). The speed of light limit is helpful in bounding how fast the matrix can change as well as in separating areas of the matrix into different "localities" which can then be handled by separate processors.
    If you had such a matrix and such a simulator, you would be able to hook up a human to a device that retrieves input from the matrix and sends output to the matrix thus generating virtual reality for the individual. Granted this all sounds alot like the movie Matrix, which i found pretty lame, but the concept is genuine.
    It's an interesting idea which is actually feasible from a computational perspective, not to be discarded so quickly.
    Regardless of whether this is or not the case, i think in the future it might be beneficial to adopt this approach in the realm of science. If we represent the universe as a matrix, then, for each phenomenon, there will an associated pattern of change in the matrix. Then, gravity for example, would be explained by it's impact on the evolution of the matrix, rather than human models (i.e matter bending space). Such an approach would yield a more abstract, rigorous and unified process of scientific analysis.
    Last edited: Apr 29, 2006
  10. Apr 29, 2006 #9


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    Something like this is already going on. See causal dynamic triangulations in quantum gravity research and the lattice approach to nonperturbative quantum physics.
  11. May 9, 2006 #10
    There's some logic that runs a little bit like this.

    1). In the future, computers will be sophisticated enough to simulate a world.
    2). Historians like to reconstruct past events.
    3). So they're likely to use these computers to run "ancestor simulations" that will show them how we lived.
    4). There will probably be more than one of these.
    5). Since there's only one real world, the odds are pretty good that we are not living in it, but are programs in one of the ancestor simulations.
  12. May 18, 2006 #11
    I think the error is in assuming premise 1 to be true.

    It's very easy to say "simulate a world", it's quite another thing to do it!

    Premise 5 seems very shaky too - why do you think there is only one real world?


    Humans put constraints on what they can achieve more often by their limited imaginations than by any limitations in the laws of physics (Alex Christie)
  13. May 28, 2006 #12
    are we living in a computer simulated world? wat do physicists think about this qn? how would we know we are not living in one? wat examples can be cited as evidence that our universe isnt juz a computer simulation?
  14. Jun 14, 2006 #13


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    I think the more important question is, can a sentient program have an awareness of the computer running it? :eek:
  15. Jun 14, 2006 #14


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    Are we aware of the neural processes that are "running our programs? And should we be? See Metzinger's proposed wall of ignorance as an essential precondition to consciousness.
  16. Jun 15, 2006 #15
  17. Jun 17, 2006 #16


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    There was an argument put forth by some speaker at the Singularity Summit at Stanford a few weeks back, whose name I cannot remember, attempting to prove that we must be living in a simulation of some sort. The basic reasoning was that other civilizations must have come into existence before we did, given the vast size of the universe and our relatively late arrival in it. If we are to take seriously the notion that humanity will achieve the singularity at some point this century, them some civilization that existed prior to our own must have already done so. Since the singularity comes to engulf the entire universe, it must have already reached us. Yet we are not experiencing it, so we must be living in a simulation of unknown nature.

    Pretty specious reasoning if you ask me.
  18. Jun 21, 2006 #17
    Refutation of the Simulation Argument

    The Simulation Argument seeks to show that it is not just possible that we are living inside a simulation, but likely.

    1 You cannot simulate a world of X complexity inside a world of X complexity.(quart-into-a-pint-pot-problem).

    2 Therefore, if we are in a simulation the 'real' world outside the simulation is much more complex and quite possibly completely different to the simulated world.

    3 In which case, we cannot make sound inferences from the world we are appear to be in to alleged real world in which the simulation is running

    4 Therefore we cannot appeal to an argumentative apparatus of advanced races, simulations etc, since all those concepts are derived from the world as we see it -- which, by hypothesis is a mere simulation.

    5 Therefore, the simulation argument pulls the metaphysical rug from under its epistemological feet.

    The counterargument does not show that we are not living in a simulation, but if we are , we have no way of knowing whether it is likely or not. Even if it seems likely that we will go on to create (sub) simulations, that does not mean we are living in a simulation that is likely for the same reasons, since our simulation might be rare and peculiar. In particular, it might have the peculiarity that sub-simulations are easy to create in it. For all we know our simulators had extreme difficulty in creating our universe. In this case, the fact that it is easy to create sub simulations within our (supposed) simulation, does not mean it is easy to creae simulations per se.
  19. Jun 21, 2006 #18
    Or they would help if our simulators have the same kind
    of hardware constraints that we have. Which would
    depend on whether they have the same kinds of
    physical laws we. Which we cannot know. because
    we are only acquainted with our simulated physical laws.
  20. Jun 22, 2006 #19
    Your (3) is based on an invalid inference.

    (Inferences are either valid or invalid, not "sound" or "unsound" - arguments and not inferences are either sound or unsound).

    Inductive inference does not entail certainty, it entails only that we assume certain premises to be true, and leads to a probabilistic and not certain outcome. One can dispute the truth of the premise "there is an outside world that we cannot directly detect which has certain properties which include amongst them the running of a simulation of which we are part", but disputing the premises of an argument has nothing necessarily to do with the validity of the inferences within the argument. Hence your (3) is incorrect.

    The rest of your argument rests on (3), hence is unsound.

    Best Regards
  21. Jun 22, 2006 #20
    It remains the case that we cannot make better-than chance inferences from the world we are appear to be in to alleged real world in which the simulation is running. Certainty is a red-herring. The SI only seeks
    to show that simulation is more likely than not.
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