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

scottaaronson.com

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

#221

Post by Ntrails »

frobozz wrote: post #145
GuiA wrote: post #125

Earlier quoted context omitted.

There's evidence that your brain is influenced by e.g. certain chemicals in your bloodstream produced by gut bacteria. https://www.theatlantic.com/health/archive/2015/06/gut-bacte... So the brain in a jar model where the only interface with the real world is through nerves is most probably wrong; now your jar also needs a stomach with a fully developed microbial ecosystem. And that's just one recent mechanism that wa…

No, at most you can say it requires a way to introduce those chemicals into the bloodstream in the brain. Actually, all you need is a way to stimulate the same receptors that are stimulated by those chemicals. Just as with unit testing, you don't actually need to hook up your SUT to a real environment, you just need to hook it up to something that will exercise the same interface as a real environment.

Indeed. I over-simplified - but whatever the mechanism people refer to it's mockable.

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

#222

Post by Ntrails »

intended wrote: post #132
Ntrails wrote: post #115

Earlier quoted context omitted.

> So if you want to simulate yourself, you have to simulate the universe. This doesn't gel with me. I go back to brain in a jar stuff - I'm just streaming packets of data from nerves and processing them. Whether the "body" I'm responding to is real is pretty hard to guarentee.

The simple and scientific answer is that you are not a brain in a jar. Its a mind body system, as much if not more than it is just a mind + body. The you who makes decisions on a hungry stomach, is a very different person who makes decisions when satiated, and so on.

>The simple and scientific answer is that you are not a brain in a jar.

The question is just about simulation. Brain in a jar is an arbitrary thought experiment (Kant's(?) evil genius, or indeed "The Matrix" if you prefer) about how you can be sure your environment is real.

In this there's no information assumed about what is real, just that I'm a unit (brain) processing input (electrical impulses/chemicals/whatever) which are fed to me from a source (unknown). For you to say "you just aren't" and then rely on evidence from the very systems that are being described as compromised is to miss the point.

Don't bring "simple and scientific" to a philosophy fight.

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

#223

Post by calebm »

M_Grey wrote: post #196
mb_72 wrote: post #85

Earlier quoted context omitted.

Indeed; the 'simulation universe' possibility I find (oddly I know!) comforting, and this has provided me with a way of understanding to some degree the comfort offered by religion to many people, while at the same time I still can't understand the religious aspect itself.

Just replace "Simulators" with "God", and you'll find that your beliefs are virtually indistinguishable from a religious conviction. In that light, the comfort it provides is by no means hard to understand.

"In [God] we live and move and have our being." (Acts 17:28)

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

#224

Post by ue_ »

kobeya wrote: post #141
sillysaurus3 wrote: post #68

Earlier quoted context omitted.

There are many questions in life that are interesting to consider, independent of whether they're falsifiable. It tends to get boring to consider only questions that can be experimentally proven, though different people have different interests. Questions about society and human nature are worth considering, for example, but it's difficult to do controlled experiments. There's some truth to "watch out for wishful thi…

> There are many questions in life that are interesting to consider, independent of whether they're falsifiable. It tends to get boring to consider only questions that can be experimentally proven... You say "boring", I say "ruthlessly pragmatic." It could be argued, crudely, that the non-verifiable questions are akin to epistomatic masturbation. We are drawn to them, and debating them makes us feel good, but the res…

I don't see any particular reason to subscribe to pragmatism; epistomatic masturbation sounds good, and from a hedonistic perspective I think I'd rather take that.

You say "ruthlessly pragmatic", I say "boring".

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

#225

Post by hasenj »

GuiA wrote: post #125
Ntrails wrote: post #115

Earlier quoted context omitted.

> So if you want to simulate yourself, you have to simulate the universe. This doesn't gel with me. I go back to brain in a jar stuff - I'm just streaming packets of data from nerves and processing them. Whether the "body" I'm responding to is real is pretty hard to guarentee.

There's evidence that your brain is influenced by e.g. certain chemicals in your bloodstream produced by gut bacteria. https://www.theatlantic.com/health/archive/2015/06/gut-bacte... So the brain in a jar model where the only interface with the real world is through nerves is most probably wrong; now your jar also needs a stomach with a fully developed microbial ecosystem. And that's just one recent mechanism that wa…

It's just another attached input device.

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

#226

Post by chenelson »

TelmoMenezes wrote: post #131
GuiA wrote: post #107

Earlier quoted context omitted.

Except that your mind is not an isolatable computation - it is influenced by your body, which is in turn influenced by its immediate environment, in turn influenced by the rest of the universe in an ever expanding nested fashion. So if you want to simulate yourself, you have to simulate the universe.

> Except that your mind is not an isolatable computation This doesn't follow from what you write next. You are saying that the computation needed to generate a mind is very large. I agree that it might be the case, and I would say that nobody knows how large. Do you really need to simulate in minute detail what is going on in every distant galaxy? Seems doubtful, but who knows? All I'm saying is that if this computat…

So...ever look up at the night sky? Are you not looking at information, and are you certain you understand the semantic and semiotic content that is being transmitted? Just because data is not explicit as a Pepsi commercial doesn't mean, a priori, we are without affect or effect.

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

#227

Post by dinfinity »

vidarh wrote: post #193
cousin_it wrote: post #169

Earlier quoted context omitted.

That doesn't seem right. If tomorrow the mass of your ashtray started fluctuating in Morse code, spelling out "hello from the simulation master" and replying to your questions intelligently, your first instinct wouldn't be to update the standard model.

To be more precise: The absence of ashtrays fluctuating in Morse code and spelling out messages or other clear signs of influence is not evidence of the absence of meddling. We can not realistically know whether or not someone is meddling with a simulation we are in because there are infinite ways they could do so that would be indistinguishable to us from "just the way the universe is". E.g. for what we know quantum…

> Why hasn't some immature "simulation master" written their name across the night sky with giant fluorescent penises, for example.

Did you not catch the election of Donald Trump?

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

#228

Post by gjm11 »

Myrmornis wrote: post #66

Can someone explain the first bit of the last sentence? > if our world is a simulation, then whoever is simulating it seems to have a clear preference for the 2-norm over the 1-norm Is it basically saying that space looks Euclidean at a range of scales and Pythagoras crops up everywhere or is it saying something else / more sophisticated? What would the Universe look like if its creator favored a 1-norm?

I think he's referring less to the geometry of space(-time) and more to the structure of quantum mechanics.

Classical probabilities are positive real numbers that add up to 1. (The 1-norm of the vector of probabilities is 1.) Quantum ampltiudes are complex numbers whose squared absolute values add up to 1. (The 2-norm of the vector of amplitudes is 1.)

A universe made by someone who preferred 1-norms would more likely be classical rather than quantum.

For more on this from the author of the linked blogpost, see here: http://www.scottaaronson.com/democritus/lec9.html or the corresponding bit in his excellent book "Quantum computing since Democritus".

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

#229

Post by SomeStupidPoint »

simonh wrote: post #40
SomeStupidPoint wrote: post #17

Earlier quoted context omitted.

Why do I need to convince you I experience qualia? You're welcome to propose models that omit it, but they'll fail basic logic to me: they fail to explain the only experiment Im absolutely sure of the results of and which is continually running while I'm existing. Im less sure gravity exists than that qualia does for me. It's entirely possible no one else does, or that they experience a different qualia. It's also no…

To me that, and 'I think therefore I am' are just I'm a special snowflake arguments. I take the simulated Intelligence argument the same way. Suppose you could create a simulation of an intelligence that was indistinguishable from a real one? Well then, you'd have created an artificial intelligence. If such a thing reported that it experienced qualia I'd have no reason to doubt it. Edit: to put it differently. Suppos…

I think you're wrong about them being "special snowflake" arguments, and likely miss the point of them.

Those arguments are very low-level in the intellectual stack, and can only address matters of subjective self because what they seek to establish or discuss is more fundamental than concepts like objectivity. (Well, cogito ergo sum is establishing an objective fact from a subjective one to give a basis for later objective discovery.)

Any full accounting of the world must explain the mechanism by which I experience it, or it hasn't explained the only part of the world Im sure exists (my experience of it), and hence can't be a full accounting. You can have a very good predictive model for features of that experience, but neglecting that experience -- qualia -- is leaving a major thing unexplained.

Similarly, cogito ergo sum is likely better phrased as "computation ergo existence" -- the process of doubting is a form of doing something, and so something must exist which is doing that (or is that process). This establishes that there must be some sort of existence, even if it's just a brain in a jar, random memory from quantum noise, etc. You can't doubt there's an existence, because the very act of doubting is proof of existing. You can only doubt the form of it.

I also disagree that we'd have no reason to doubt the claim, but I agree we have no a prior reason to reject it.

Your edit also makes a major assumption: that we know what causes qualia (our brain structure). That's the very thing being debated, so you're just begging the question.

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

#230

Post by XorNot »

inopinatus wrote: post #49
intjk wrote: post #31

Earlier quoted context omitted.

At the end of the article, Scott essentially says the same thing, but emphasizing the other side of the coin: > [...] the question of whether the universe “really” “is” a simulation has barely come up. Why would it, when there are so many more fruitful things to ask?

I always felt that the point of asking this question was not the answer itself, but that theorising how it might be implemented could lead to hacking the sandbox. IANATP but I've read, for example, that violating Lorentz invariance is an active research area.

Or looking for aliasing from a lattice QCD simulation in cosmic microwave background...
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