Are We Living In a Computer Simulation? • Hacker News Board

Re: Are We Living In a Computer Simulation?

#51

Post by hugh » Sun, Jul 06, 2008, 7:36 PM UTC

jey wrote: post #39

hugh wrote: post #30

Earlier quoted context omitted.

Personally I really doubt (2). I work in theoretical condensed matter physics, and it's awfully hard to accurately simulate anything with more than a very small number of atoms. Sure, computers will continue to get faster for a while, but these problems scale very badly with the size of the system, and we're not all many orders of magnitude away from the fundamental limits of computation. I suspect that even if you w…

You're assuming that we'll be using the same approaches (e.g. molecular dynamics on classical computers) to do the simulation. We don't know what methods and techniques will be available in the future, so we can't confidently claim that it'll forever be out of reach. I bet there's some room for improvement over the current crude techniques.

Oh, I'm not assuming that. I'm just not-assuming the opposite.

Re: Are We Living In a Computer Simulation?

#52

Post by gojomo » Sun, Jul 06, 2008, 7:44 PM UTC

hugh wrote: post #28

gojomo wrote: post #21

Earlier quoted context omitted.

That he thinks the argument is sound but does not agree with "(3) we are almost certainly living in a computer simulation" means Bostrom believes either: (1) the human species is very likely to go extinct before reaching a "posthuman" stage; or (2) any posthuman civilization is extremely unlikely to run a significant number of simulations of their evolutionary history (or variations thereof).

No, he may be entirely agnostic on all three, neither believing nor disbelieving any of them. That seems like a pretty sensible attitude to have, actually.

In the FAQ, Bostrom says he personally assigns about 20% probability to the idea we are living in a simulation, and that he views (2), that the posthumans are unlikely to run ancestor simulations, a bit more likely than the others.

Colloquially, it would be fair to say he 'believes' (2) -- as in the most likely of exclusive options, if he had to make one choice, if he had to bet, etc. And he definitely believes Union(2+3) more than (1).

Re: Are We Living In a Computer Simulation?

#53

Post by ericb » Sun, Jul 06, 2008, 8:15 PM UTC

trominos wrote: post #34

hugh wrote: post #30

Earlier quoted context omitted.

Personally I really doubt (2). I work in theoretical condensed matter physics, and it's awfully hard to accurately simulate anything with more than a very small number of atoms. Sure, computers will continue to get faster for a while, but these problems scale very badly with the size of the system, and we're not all many orders of magnitude away from the fundamental limits of computation. I suspect that even if you w…

It may be possible that each universe will simulate a substantially simpler universe; it would of course be impossible to tell whether you universe has "lower resolution" from the inside, cause you'd have no frame of reference.

Perhaps our universe's resolution bottoms out at the quantum level, where a hack saves processing at the lowest level by using probabilities and a lazy evaluation scheme instead of deterministic calculations.

Re: Are We Living In a Computer Simulation?

#54

Post by lg » Sun, Jul 06, 2008, 8:22 PM UTC

eyudkowsky wrote: post #20

The Simulation Argument is not that we are living in a computer simulation. It is that you must reject at least one of the 3 propositions: (1) we are not living in a computer simulation (2) the human species will give rise to descendants that have the power to run lots of simulations (3) at least a few of them will run ancestor simulations. Which of these three do you think is untrue? Alternatively you could reject t…

> Alternatively you could reject the Simulation Argument that says the three propositions are mutually incompatible - but if so, how?

Suppose the universe started normally a few billion years ago (explosion) and humans appeared several million years ago and we're not in any simulation right now. But at some point in the future there will be such simulations and "people" will "live" in them. Unlikely? Sure. Impossible? Nope.

Re: Are We Living In a Computer Simulation?

#55

Post by hugh » Mon, Jul 07, 2008, 6:04 PM UTC

Panoramix wrote: post #41

danteembermage wrote: post #32

Earlier quoted context omitted.

One possible solution is to elongate the time-steps; if we take a million years to simulate one second of simulation time you could get by with a lot less computing power.

The problem is that the scales involved are so ridiculously large that it could easily take 1 billion years to simulate one second. Even with 1 million years per second, simulation of a thousand years would require something like the age of the universe to compute. In that case, these "beings" could not be our descendants since they live in a universe with different laws.

Actually, at a million years per second, the age of the universe (so far) would go by in five simulated hours. I don't want to speculate on how long we have until heat death, but I doubt it's long enough to simulate a single human lifespan at a million years per second.

Re: Are We Living In a Computer Simulation?

#56

Post by byrneseyeview » Mon, Jul 07, 2008, 8:21 PM UTC

jodrellblank wrote: post #43

danteembermage wrote: post #32

Earlier quoted context omitted.

One possible solution is to elongate the time-steps; if we take a million years to simulate one second of simulation time you could get by with a lot less computing power.

If you do that, and load some information from a slow storage device (hard disk), calculate on it for a hundred years, then write it back, load some more, repeat, until you have computed "one planck time" accross your entire simulated universe... ... at what point in the loading, crunching, saving, does the information inside feel concious and self aware 'in realtime'?

Since this could apply to your life being run on a different substrate, with no actual effect on your perception, I don't see how this is a useful question.