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Your yearly dose of is-the-universe-a-simulation

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Re: Your yearly dose of is-the-universe-a-simulation

#21

Post by setr »

snowwrestler wrote: post #6

Here's what I wrote in a comment here last year about the Bostrom simulation argument specifically: The simulation argument, going back to Bostrom, relies on two flaws. 1) It leverages our optimism to corrupt our understanding of statistics and logic. It essentially says that if you think humanity doesn't destroy itself, then our descendants will probably try to simulate us. But of course if you just take a statistic…

The way I usually see it is that the descendants will try to replicate humanity in a smaller universe, who will then recursively and eventually instantiate their own replication

Not that we're currently being replicated by our actual descendants, but by our higher level's descendents.

Eventually ofc hitting the base case where the simulation cannot support further simulation (which might be us, if we never manage to successfully simulate our own universe, with whatever hacks and approximation we can find).

And ofc, if we are a simulation of a higher level's history, and the simulation is correct (to all necessary degrees), then we must be heading towards the sane point where we would render a simulation (unless the approximation fails to support it).

So if level 1 managed to simulate, then all further levels (until base) should also simulate.

And if level 1 can simulate, then it probably will.

Re: Your yearly dose of is-the-universe-a-simulation

#22

Post by simonh »

AnonNo15 wrote: post #18
snowwrestler wrote: post #6

Here's what I wrote in a comment here last year about the Bostrom simulation argument specifically: The simulation argument, going back to Bostrom, relies on two flaws. 1) It leverages our optimism to corrupt our understanding of statistics and logic. It essentially says that if you think humanity doesn't destroy itself, then our descendants will probably try to simulate us. But of course if you just take a statistic…

Regarding you second point - you don't need to simulate the Universe at 1:1 scale to reliably replicate the past states of a certain region. For example, Earth itself can be simulated at full resolution only within a thin shell centered on it's surface, say +/-10 km from geoid. There are no observers at the core, so a simplified model would do, as long as plate tectonics is reproduced accurately enough.

That doesn't work though. Even a game of billiards is so complex and so dependent on external influences that a change in state in an electron at the edge of the observable universe can have an observable effect on the outcome.

http://www.anecdote.com/2007/10/the-billiard-ball-example/

Re: Your yearly dose of is-the-universe-a-simulation

#23

Post by codebolt »

michaelmrose wrote: post #11
codebolt wrote: post #3

Earlier quoted context omitted.

To me, even if we ignore the God debate, there are some big problems with theories like these because they irreverently presuppose that everything including the human mind can be reduced to mechanical/mathematical principles. This ignores things like the problem of qualia (which I'm subjectively convinced is real), and the Penrose-Lucas argument for why there is a non-computational component to human consciousness.

The universe is composed of particles, waves, or strings or whatever you prefer math describes each constituent part so why does math not describe the whole?

Like I said, I don't accept this physicalist assertion, because it ignores the problem of qualia and the Penrose-Lucas argument (which demonstrates quite clearly how the human mind is able to violate Gödels incompleteness theorems, and therefore is not equivalent to any purely computational system).

Re: Your yearly dose of is-the-universe-a-simulation

#25

Post by tbabb »

snowwrestler wrote: post #6

Here's what I wrote in a comment here last year about the Bostrom simulation argument specifically: The simulation argument, going back to Bostrom, relies on two flaws. 1) It leverages our optimism to corrupt our understanding of statistics and logic. It essentially says that if you think humanity doesn't destroy itself, then our descendants will probably try to simulate us. But of course if you just take a statistic…

If you tweak Bostrom's argument, it can sort of make sense. For example, if you believe a simulated human mind is "just as good" as a real mind, then it might make sense to colonize uninhabitable planets by building simulations there. It might even be easiest to colonize all planets this way. And if you suppose a future with lots of successful planet colonization, then there could easily be a lot more simulated minds in the history of the universe than real ones.

However, I think the main problem with Bostrom's argument is an epistemological one: It supposes an entire outer world, about which we have no evidence and know nothing. It's like opening Sagan's garage[1], but instead of asserting an invisible dragon, you're asserting an entire universe. It is the least parsimonious hypothesis you could make, because it doubles the complexity of the universe!

[1] http://rationalwiki.org/wiki/The_Dragon_in_My_Garage

Re: Your yearly dose of is-the-universe-a-simulation

#27

Post by teraflop »

setr wrote: post #21
snowwrestler wrote: post #6

Here's what I wrote in a comment here last year about the Bostrom simulation argument specifically: The simulation argument, going back to Bostrom, relies on two flaws. 1) It leverages our optimism to corrupt our understanding of statistics and logic. It essentially says that if you think humanity doesn't destroy itself, then our descendants will probably try to simulate us. But of course if you just take a statistic…

The way I usually see it is that the descendants will try to replicate humanity in a smaller universe, who will then recursively and eventually instantiate their own replication Not that we're currently being replicated by our actual descendants, but by our higher level's descendents. Eventually ofc hitting the base case where the simulation cannot support further simulation (which might be us, if we never manage to…

> And ofc, if we are a simulation of a higher level's history, and the simulation is correct (to all necessary degrees), then we must be heading towards the sane point where we would render a simulation (unless the approximation fails to support it).

Even if a universe-scale simulation is physically possible, why should we expect it to faithfully repeat the same sequence of events that happened in the "outer" universe?

Leaving aside the question of why a civilization would want to try to simulate its own history, it seems very unlikely that it would be possible to reconstruct the initial conditions to get such a simulation started. The current physical state of the universe is the result of billions of years of thermodynamically irreversible processes. Furthermore, there are vast regions of the universe that interacted in the past, but are now permanently beyond each others' cosmological horizons due to the expansion of the universe. A faithful historical simulation would require precisely reconstructing staggering amounts of information, and even with the physicist's concept of "infinitely advanced technology", it's hard to imagine how such a thing could be done.

Re: Your yearly dose of is-the-universe-a-simulation

#28

Post by moxious »

planetjones wrote: post #24

But couldn't our universe be being simulated by a species far more advanced and discrete to anything the human race has ever encountered? How do we know that another form of life doesn't find everything that we find super complex extremely trivial ?

It could be the case that we are being simulated by a far superior alien species. It could also be that invisible pink unicorns in the 15th dimension control all of our thoughts and only want us to believe this.

Without being tongue in cheek, I'll observe that the empirical evidence for both of these ideas is equal in quantity.

We don't know for sure that these things aren't true. But to ask that question is to inappropriately shift the burden of proof away from the claimer. Whoever claims something (we live in a simulation) should put up the evidence or get out. It's not up to bystanders to disprove the assertion. Connecting this to current events, even the president of the USA doesn't get to make baseless claims that his predecessor wiretapped him and get away with shifting the burden of proof to the FBI to prove he wasn't.

This "reversal of burden of proof" is a classic but invalid way to make a point.

Re: Your yearly dose of is-the-universe-a-simulation

#29

Post by AnonNo15 »

simonh wrote: post #22
AnonNo15 wrote: post #18

Earlier quoted context omitted.

Regarding you second point - you don't need to simulate the Universe at 1:1 scale to reliably replicate the past states of a certain region. For example, Earth itself can be simulated at full resolution only within a thin shell centered on it's surface, say +/-10 km from geoid. There are no observers at the core, so a simplified model would do, as long as plate tectonics is reproduced accurately enough.

That doesn't work though. Even a game of billiards is so complex and so dependent on external influences that a change in state in an electron at the edge of the observable universe can have an observable effect on the outcome. http://www.anecdote.com/2007/10/the-billiard-ball-example/

It doesn't prevent simulating A universe. You can then compute a difference between the simulated past state and real past state based on (partial) information about the past state.

Then you go back and iterate again, eventually improving the accuracy of simulation until there is no distinguishable difference between simulated state and real past state.

The simulation might end up being not a perfect copy, but it would reach the point where it will be impossible to find any discrepancies.

Re: Your yearly dose of is-the-universe-a-simulation

#30

Post by fsloth »

baddox wrote: post #14
snowwrestler wrote: post #6

Here's what I wrote in a comment here last year about the Bostrom simulation argument specifically: The simulation argument, going back to Bostrom, relies on two flaws. 1) It leverages our optimism to corrupt our understanding of statistics and logic. It essentially says that if you think humanity doesn't destroy itself, then our descendants will probably try to simulate us. But of course if you just take a statistic…

> But it is impossible to completely simulate a system from inside that system--that's basic thermodynamics I haven't heard quite that argument before. Couldn't it just be simulated slower than real-time? Or is memory the issue?

"I haven't heard quite that argument before. Couldn't it just be simulated slower than real-time? Or is memory the issue?"

The "real time" in simulation is not affected by how long a single time step takes to evaluate in the real world.

https://xkcd.com/505/

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