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On whether we're living in a simulation

scottaaronson.blog

121–130 of 206 posts

Re: On whether we're living in a simulation

#121
post #98

Earlier quoted context omitted.

> There are whole regions of space with no actual observer. Those can be swapped to disk, What disk? Where is this disk? Suppose the universe contains 10⁸⁰ atoms. And we somehow figure out a way to store 10 bits of information per atom, giving our universe a storage capacity of 10⁸¹ How do you propose to simulate a universe that requires 10⁸¹ + 1 bits to describe? What disk are you going to swap the extra information…

Lazy algorithm and generator functions

Even gzip will store lots of zeros in a tiny, tiny space.

If a region of space isn't observed, it's a big fat load of null. If it is observed up close, whatever persistent storage you use for that space can be wiped, when the observer ceases to exist.

Even now, when we observe close planetary systems, it isn't as if we are looking at all the atoms. We certainly aren't observing all the space on the planets. It's all mega fuzzy, and be therefore a fuzzy property. An approximation.

But of the observer population spikes, then too much would be observed and active at once... crash!

Re: On whether we're living in a simulation

#122
post #22

Earlier quoted context omitted.

That variant is simply Pascal's Wager. It's more interesting to ask whether, of we are in a simulation, it is possible to prove and/or find "escapes". All our experience with computational sandboxes so far is that preventing information leaks or escapes is extremely hard. Of course, we still have the problem that if we fi d nothing we don't know what that means. From my perspective, I'm on the side that it's a fun ph…

> All our experience with computational sandboxes so far is that preventing information leaks or escapes is extremely hard. I believe this is due to the path-dependent nature of our hardware architecture, not anything fundamental. x86 is not really designed with virtualization in mind. Theoretically, perfect airtight simulation is the primary ability of computers, and we're just too sloppy to exploit it properly. Ano…

Can entities inside the simulation get info about your CPU architecture?

(From HAKMEM):

Item 154 (Bill Gosper): The myth that any given programming language is machine independent is easily exploded by computing the sum of powers of 2. If the result loops with period = 1 with sign +, you are on a sign-magnitude machine. If the result loops with period = 1 at -1, you are on a twos-complement machine. If the result loops with period greater than 1, including the beginning, you are on a ones-complement machine. If the result loops with period greater than 1, not including the beginning, your machine isn't binary -- the pattern should tell you the base. If you run out of memory, you are on a string or bignum system. If arithmetic overflow is a fatal error, some fascist pig with a read-only mind is trying to enforce machine independence. But the very ability to trap overflow is machine dependent. By this strategy, consider the universe, or, more precisely, algebra: Let X = the sum of many powers of 2 = ...111111 (base 2). Now add X to itself: X + X = ...111110. Thus, 2X = X - 1, so X = -1. Therefore algebra is run on a machine (the universe) that is two's-complement.

Re: On whether we're living in a simulation

#123
post #7

"If they say, maybe you should live your life differently, just from knowing that you might be in a simulation, I respond: I can’t quite put my finger on it, but I have a vague feeling that this discussion predates the 80 or so years we’ve had digital computers! Why not just join the theologians in that earlier discussion, rather than pretending that this is something distinctive about computers? Is it relevantly dif…

>Is it relevantly different here if you’re being dreamed in the mind of God or being executed in Python?

Yes. Simulations have limitations.

Think about Conway's Game of Life. You have complete control over the simulation - you determine the starting positions and you can mess with its memory while it's running to alter the current state. However, you cannot always predict what the end result of the simulation is without actually simulating it. In a general case, the end result of the simulation is unknowable until you run the simulation.

If the universe is a simulation then I think it's likely that it would be a simulation like Conway's Game of Life. It will have some limitations that even the creator couldn't know to control. This is quite different from what the Christian god is treated as.

Of course, it could be that the greater universe does not suffer from mathematical problems like the incompleteness theorem or the halting problem. But that would be something very difficult to imagine.

Re: On whether we're living in a simulation

#124

I humour the idea that we probably are in one, and that its creator(s) are asking the same questions like us, like if there is free will. If the idea of new universes being spawned from black holes is a thing, and the Hawking radiation emitted from them is somehow measurable, it would be interesting to see if unexpected data is returned! Sod's law it would take the age of our own universe to find out, hopefully it ru…

We are not in one. And it comes down to resources and self preservation. Firstly: you need to recognise that virtual life is as real as physical life (you feel and experience a world - it doesn't mater if its digital representation or physical one). Now consider this: If you live in a simulation, a VM, then you serve some kind of purpose to person that spawned you. A game, a experiment, a collage thesis... whatever.…

Aaronson mentions this in his post re: 'lower resolution' and entropy. It's a fair point you make.

It's not known if any 'parent' universes would be subject to the same timeframes as we are, though. By rights on that point their universe would operate more slowly from our frame of reference as per having more stuff/energy in their universe and ours potentially being a subset of theirs.

Re: On whether we're living in a simulation

#125
post #36

Earlier quoted context omitted.

And isn't the fact that the universe seems to be a result of computation in fact just because we are abstracting it with mathematics?

What else would it be but computation? Coming up with something that isn't computation in some form or other is exceedingly hard. I'm not even sure it's meaningfully possible.

Computation call still have non-determinism. For example, the computation gives e.g. 2 possible options at every step (both physically valid). Then a "consciousness" decides which of the 2 options it prefers, and that's the part we'll see and the other part of the tree is simply not observed.

So you can compute it to some extent, just not fully.

Re: On whether we're living in a simulation

#126
post #7

"If they say, maybe you should live your life differently, just from knowing that you might be in a simulation, I respond: I can’t quite put my finger on it, but I have a vague feeling that this discussion predates the 80 or so years we’ve had digital computers! Why not just join the theologians in that earlier discussion, rather than pretending that this is something distinctive about computers? Is it relevantly dif…

Depending on how a simulation works, it could introduce phenomena or artifacts like results of numeric approximations into the universe that can be tested for.

I would argue that unless the universe is using some sort of compute saving heuristic, then it is not in fact a simulation, even if it can be, and is run on a computer of some kind, because in that case it has its own independent “existence” in a mathematical sense. For example, if we could “run” an exactly identical copy of our own universe on a computer without errors, it is not really a second universe, but the same one, in the same sense that I could write out an equation and solve it on paper, or solve it with a computer algebra system, but they are still the same equation not two equations. This is based on the assumption or idea that mathematical existence is identical to physical existence.

Re: On whether we're living in a simulation

#127
post #126
post #7

"If they say, maybe you should live your life differently, just from knowing that you might be in a simulation, I respond: I can’t quite put my finger on it, but I have a vague feeling that this discussion predates the 80 or so years we’ve had digital computers! Why not just join the theologians in that earlier discussion, rather than pretending that this is something distinctive about computers? Is it relevantly dif…

Depending on how a simulation works, it could introduce phenomena or artifacts like results of numeric approximations into the universe that can be tested for. I would argue that unless the universe is using some sort of compute saving heuristic, then it is not in fact a simulation, even if it can be, and is run on a computer of some kind, because in that case it has its own independent “existence” in a mathematical…

Such a test wouldn't show we are in a simulation. It would show the universe follows weird rules, which is already what we know from quantum physics.

Re: On whether we're living in a simulation

#128

Earlier quoted context omitted.

That's not an atheist. That's an agnostic theist (aka deist). Gnostic Theist: My God exists. Agnostic Theist: I accept the concept of deity(ies), but it's not relevant to me Agnostic Atheist: I don't accept the concept of deity(ies), but it's not relevant to me. Gnostic Atheist: Deities do not exist.

Atheism does not mean that you believe deities do not exist. It means you do not have the belief that they do. The absence of a belief in something does not imply a belief in the absence it. A definitive belief that deities do not exist is sometimes called strong atheism.

> A definitive belief that deities do not exist is sometimes called strong atheism.

Yes indeed!

My variation of atheism is often called "ignostic" -- that is, I can't tell you if I believe in god or not until you tell me what, exactly, you mean by "god".

The more proper name for this is "incompetent atheism", but I dislike that name because it implies a different meaning than it has.

Philosophy is fun!

Re: On whether we're living in a simulation

#129
post #119

Earlier quoted context omitted.

If there's a simulation and we as a species are living in it, and bound by its rules (laws of physics, etc.) then you get into the question of who made said simulation with the rules that constrain us. Since this simulator sysadmin has control over us in ways we cannot comprehend or push back against in a meaningful way, I'd say it counts as a higher power. Since its existence cannot currently be proven false through…

No, the origin beliefs in this case aren't really faith. Let me frame that as questions: do you: - Believe that we will be able to create a true AI, with self-consicousness? - Believe that we will some day have enough energy and compute power to create a simulation that could contains billions of those consciousness? - Believe that if we are able to do so, we will do it (aka no governmental body will prevent a simula…

There are people who engage in the thought exercise without believing it's true, but there are definitely people who believe it's true. See: Elon Musk (at least he did a few years ago)

Re: On whether we're living in a simulation

#130
post #126

Earlier quoted context omitted.

Depending on how a simulation works, it could introduce phenomena or artifacts like results of numeric approximations into the universe that can be tested for. I would argue that unless the universe is using some sort of compute saving heuristic, then it is not in fact a simulation, even if it can be, and is run on a computer of some kind, because in that case it has its own independent “existence” in a mathematical…

Such a test wouldn't show we are in a simulation. It would show the universe follows weird rules, which is already what we know from quantum physics.

If you can understand the nature of the simulation and then make and confirm different otherwise surprising and unexplainable experimental predictions consistent with it, this is a good as evidence gets scientifically. Sure there could always be some more complex or unimagined explanation for the same results, but that is reasonable to dismiss with Occam’s razor. If you can’t accept this, you would need to reject all past scientific discoveries as well, as this is how they were all confirmed.

“Weird rules” to me just sounds like observing unexplainable things. It’s very different from being able to say before hand “if the universe is simulated using x bit floating point computation, we will get result 1 in this experiment, and if it has infinite precision as we’d expect from a non heuristic physical universe, we would get result 2.”

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