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On whether we're living in a simulation

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Re: On whether we're living in a simulation

#31

Post by vidarh »

PeterisP wrote: post #17
k__ wrote: post #4

What's the reason for the simulation to be smaller than the simulator? Can't it just be the same but slower? This wouldn't be perceivable from the inside.

Quantity of information - a simulator whose state itself can be expressed in X bits can't possibly have a simulation with X+1 bits of incompressible state.

Yes, but assuming much incompressible state is already assuming to know a lot about the nature of the simulation, ranging from size, longevity, to the extent which the structure of our perceived universe is the way it is to enable an outside simulator to take shortcuts we don't know about.

Re: On whether we're living in a simulation

#32

Post by Beijinger »

lukan wrote: 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…

"The whole simulation hypothesis seems like a new way to introduce theological concepts with modern tech. Cannot be disproved, cannot be verified."

I have bad news for you. There is no proof in Science. :-(

The problem is, that if it is possible to simulate us, then the likelihood that we are simulated is much higher, than that we are not. This is a problem!

And yes, can be tested. "Stacking Problem". The simulation may be not bound to some physical principles or some physical principles may be changed (e.g. real time vs. simulated time). But some physical laws exits in the real world for sure and the simulation if bound to it. E.g. exponential mathematics and limited ressources. The the simulation would have to avoid, that the simulation runs it own simulation that runs it own simulation... Even the biggest super quantum computer would go belly up at some point. So if we are living in a simulation, there should be an interest to avoid that we are running our own simulations.

Re: On whether we're living in a simulation

#33

Post by 5350-uiop-1130 »

dsego wrote: post #20

Zizek says that with quantum physics, we've caught God with His pants down. Saying that some of the programming of our universe is undetermined in the same way that parts of computer game levels aren't meant for the player to go to. https://youtu.be/ywVHFo1na38

> Zizek says that with quantum physics, we've caught God with His pants down.

am i the only one who finds zizek insufferable. he is so self absorbed.

you ask him a yes/no question and he spends 30 minutes giving an anecodte about himself.

Re: On whether we're living in a simulation

#34

Post by TheOtherHobbes »

FrustratedMonky wrote: post #15
amelius wrote: post #5

> My personal belief is that the deepest things we’ve learned about quantum gravity—including about the Planck scale, and the Bekenstein bound from black-hole thermodynamics, and AdS/CFT—all militate toward the view that the answer is “yes,” that in some sense (which needs to be spelled out carefully!) the physical universe really is a giant Turing machine. Doesn't the non-determinism of QM in fact say that there's f…

"non-determinism of QM". Think this is still in doubt. There is the whole branch of physics called 'super determinism' , trying to find the underlying causes of events that look 'undetermined'.

Yes. Do hidden variables and processes exist? The universe could be perfectly deterministic from outside but appear very random here.

It's an open question. No one knows the answer.

That's why I think it's an interesting question.

Personally I find the references to god or theology offensive and distracting. These are perfectly valid questions to ask. They don't imply any kind of biblical god. They don't even imply a creator.

We only fall back to creators because we can't imagine that something, or some set of rules, or some arbitrary process, or whatever might Just Exist.

It's quite possible this is a simulation - in the sense that it's a secondary not a primary reality - that appeared spontaneously, and no one/nothing created it deliberately.

Re: On whether we're living in a simulation

#35

Post by WithinReason »

Karellen wrote: post #23
k__ wrote: post #4

What's the reason for the simulation to be smaller than the simulator? Can't it just be the same but slower? This wouldn't be perceivable from the inside.

> > But because their simulations will have to run on computers that fit in our universe, presumably the simulated universes will be smaller than ours—in the sense of fewer bits and operations needed to describe them. > Can't it just be the same but slower? The number of bits needed to simulate another universe can't be larger than the number of bits we can store in this universe - there isn't enough space to store t…

many algorithms allow trading space for time

Re: On whether we're living in a simulation

#36

Post by vidarh »

james-bcn wrote: post #9
amelius wrote: post #5

> My personal belief is that the deepest things we’ve learned about quantum gravity—including about the Planck scale, and the Bekenstein bound from black-hole thermodynamics, and AdS/CFT—all militate toward the view that the answer is “yes,” that in some sense (which needs to be spelled out carefully!) the physical universe really is a giant Turing machine. Doesn't the non-determinism of QM in fact say that there's f…

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.

Re: On whether we're living in a simulation

#37

Post by narush »

The OG Nick Bostrom argument [1] makes an argument for simulation theory with some reasonably simple math you can see in the paper with only a few variables:

- `f_p` - Fraction of all human-level technological civilizations that survive to reach a posthuman stage

- `f_I` - Fraction of posthuman civilizations that are interested in running ancestor-simulations

- `N_I` - Average number of ancestor-simulations run by a posthuman civilization

- `H` - Average number of individuals that have lived in a civilization before it reaches a posthuman stage

And then the formula for the fraction of observers with human-type experiences (after simplifying) is just: f_sim = (f_p * f_I * N_I) / (f_p * f_I * N_I + 1).

By first arguing that `N_I` is likely to be very large (because, pretty much, why not) -- you can thus conclude that one of these three conditions are met:

1. `f_p ~= 0` -- or the human species is very likely to go extinct before reaching a “posthuman” stage;

2. `f_I ~= 0` -- or any posthuman civilization is extremely unlikely to run a significant number of simulations of their evolutionary history (or variations thereof);

3. `f_sim ~= 1` -- or we are almost certainly living in a computer simulation.

It's all feels pretty similar to the Fermi paradox to me -- which I'm also suspicious of for reasons I can't justify properly. Something about point estimates for variables like `f_I` is... weird? Idk. I'm honestly not good enough at math to disagree - but it also feels like folks who are too good at math might be using `f_I` in equations in a way that isn't legitimate.

Like, assuming the "existence" of `f_I` as a concept to reason with -- doesn't it feel like more might be sneaking in with this assumption?

[1] https://simulation-argument.com

Re: On whether we're living in a simulation

#38

Post by bowsamic »

amelius wrote: post #5

> My personal belief is that the deepest things we’ve learned about quantum gravity—including about the Planck scale, and the Bekenstein bound from black-hole thermodynamics, and AdS/CFT—all militate toward the view that the answer is “yes,” that in some sense (which needs to be spelled out carefully!) the physical universe really is a giant Turing machine. Doesn't the non-determinism of QM in fact say that there's f…

I'm a postdoc in theoretical quantum physics and most of my colleagues believe in MWI which is deterministic

Re: On whether we're living in a simulation

#39

Post by steve1977 »

vidarh wrote: post #22
lukan wrote: 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…

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…

The only thing that could escape is information, or not?

If we „are“ a simulation, we could not leave it anyway. We could just maybe communicate with the outside, but not go there.

Re: On whether we're living in a simulation

#40

Post by AndyMcConachie »

lukan wrote: 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…

I fall back on Arthur C Clarke's, "Any sufficiently advanced technology is indistinguishable from magic."

If computers are arcane magical machines then let's project onto them our fantasies. This particular fantasy of God playing puppet master, or reality being a simulation, is really old. It's an old fantasy and we have found a new medium to project it onto.

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