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Physicists To Test If Universe Is A Computer Simulation

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Re: Physicists To Test If Universe Is A Computer Simulation

#171

Post by moens »

XorNot wrote: post #102
jerf wrote: post #76

Earlier quoted context omitted.

I have often thought that if 20th century science tried to ram home the logical necessity of atheism, 21st century science rams home the logical necessity of agnosticism being the ground level, so to speak. If we, tiny as we still are, can even conceive of a practical way to simulate a universe (and what is truly the difference between "simulate" and "create" in the end?), how can we in good conscience fully rule out…

Agnosticism has nothing meaningful to say about this situation, because it claims to give equal weight to totally unfounded claims ("it's definitely yahweh"). Atheists would rightly consider the evidence, conclude there was a creator, but give it no due reverence because they would conclude (rightly) that none is morally due.

Meritocracy just broke all to pieces I guess.

Re: Physicists To Test If Universe Is A Computer Simulation

#172

Post by fatihdonmez »

Actually it's what most religions said about universe. It was all programmed at the beginning. All of our actions and their future possible results are known by god. The problem is how we can develop awareness about it, if we doesn't have enough perception by default. Religions say that just believe without questioning, we have reasons, we create the signs for you to believe. I don't know, but as an engineer it does look like god is the head engineer.

Re: Physicists To Test If Universe Is A Computer Simulation

#173

Post by mikeash »

cnlwsu wrote: post #16
mikeash wrote: post #5

Earlier quoted context omitted.

I'm sure they do checkpointing and can roll back in the event of a problem. This has probably happened many times already.

I cant help but picture two mice trying to reconstruct the question from a human brain

I was thinking of this one as I wrote that:

There is a theory which states that if ever anyone discovers exactly what the Universe is for and why it is here, it will instantly disappear and be replaced by something even more bizarre and inexplicable.

There is another theory which states that this has already happened.

Re: Physicists To Test If Universe Is A Computer Simulation

#174

Post by martijn_himself »

Am I right in my (very limited) understanding that they derive their 'observables' (i.e. indicators that would prove we are inside a simulation) from the assumption that the space-time continuum is discretized in a certain way?

By the time we are actually able to perform a simulation on such a scale would the numerical method not have evolved as well and possibly produce totally different kinds of 'observables'?

I realise I am totally out of my depth here :).

Re: Physicists To Test If Universe Is A Computer Simulation

#175

Post by polshaw »

jonnathanson wrote: post #167
polshaw wrote: post #164

What I would like to discuss is what purpose would simulating a universe have for the advanced civilisation? As the civilisation becomes closer to being capable of creating a perfectly simulated universe, they get less benefit from having one. If we assume the universe we are in is at least similar to 'the first', then the existence of entropy / thermodynamic laws would surely create a significant cost to universe si…

"What I would like to discuss is what purpose would simulating a universe have for the advanced civilisation?" The Douglas Adams-style answer would be that we're some kid's physics homework. Perhaps, in a sufficiently advanced civilization, building a working computer model of an advanced universe is child's play. An alternative is that the simulators inhabit a very different universe from our own, and that our simul…

If we are to say it is a perfect or near perfect simulation ('copy') then I don't see how, as stated in my first post.

It's interesting to consider if we were a different simulation. But it would still have the same limits (that the sum of the activity ('reality') in each simulation must be less large/complex than it's host), prohibiting the 'infinite simulations' concept.

It surely isn't necessary that we are similar to a host universe, but I wouldn't you say it was a necessary part of this theory?; because it all starts with the vastness of our own space(-time) as the justification for the likelihood of super-advanced civilisations. You could argue that the size of our universe implies simulations must happen, and that if our universe were a simulation the host must be larger, i suppose. If the simulations are not similar to their host, though, the foundation suggestion that a simulation could be our universe seems a little more shaky (as there would be no direct theory ('evidence') that a universe like ours could be simulated).

There is perhaps a semantic issue too.. if somewhere in this universe we are simulating something that works on different rules to our universe, is it in fact a universe, or what makes it so?

Re: Physicists To Test If Universe Is A Computer Simulation

#176

Post by oftenwrong »

mahmud wrote: post #43
songgao wrote: post #27

Please don't `kill -9` me! I'm having fun in this simulated universe.

There is a Star Trek Voyager episode where three humanoids on a planet survived a natural disaster that destroyed their planet by going into stasis and having their brains stimulated by a computer simulation for over 19 years. In that time, the adaptive computer responded to their worst fears by turning the "fun" model world full of clowns and dancers into a circus nightmare. The virtual characters created to enterta…

http://en.memory-alpha.org/wiki/The_Thaw

Re: Physicists To Test If Universe Is A Computer Simulation

#177

Post by polshaw »

ep103 wrote: post #168
polshaw wrote: post #164

What I would like to discuss is what purpose would simulating a universe have for the advanced civilisation? As the civilisation becomes closer to being capable of creating a perfectly simulated universe, they get less benefit from having one. If we assume the universe we are in is at least similar to 'the first', then the existence of entropy / thermodynamic laws would surely create a significant cost to universe si…

You started this post asking one question, and ended it asking a different (IMO much more interesting) question. To the first one though, so long as politics and war exist, there would always be reason to attempt to run simulations, regardless of the degree of advancement of a civilization. By the By, Iain Banks plays around / has a recurring thread of simulations and high powered computers in his culture series, if…

I absolutely agree, it got much more interesting as I started fleshing out my thought process.

As for the motives, for a simulation to be helpful, it would have to run at greater than real time, no? Which.. is surely impossible, at least for a complete 'perfect' simulation. Right? Imperfections (and the limit of a simulation having to be simpler than its host) would infer a finite chain of simulations, which would vastly reduce the likelihood of us existing in a simulation.

Also if these wars (etc) exist, the simulation is going to be knocked offline at some point, destroying all descendant universes, shrinking the pool of possible existent universes much further still.

So (AFAICT) we have gone from it being almost a certainty we are part of a simulation (only one true universe from infinite similar simulations), to being very unlikely.

I may check out the culture series, but i'm not one for reading much fiction, sadly.. impatient internet world that has formed me and all.

Re: Physicists To Test If Universe Is A Computer Simulation

#180

Post by ritchiea »

nnq wrote: post #125

Isn't it obvious for most that for an advanced enough simulation, it is impossible to prove that you are in a simulation from inside the simulation? Even if we find proof that our current model of reality is wrong, it would only mean we need to search for another model of reality, we can't just say "but out theory doesn't actually match the reality because the reality is actually a simulation that computes approximat…

What if we're in a simulation built by crappy programmers in an extremely advanced society?

Even advanced societies will have crappy programmers.

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