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How Bell’s Theorem proved ‘spooky action at a distance’ is real

quantamagazine.org

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Re: How Bell’s Theorem proved ‘spooky action at a distance’ is real

#161

Post by feoren »

dragonwriter wrote: post #142
feoren wrote: post #139

Earlier quoted context omitted.

My understanding is that "Wave function collapse" is an artifact of one of the many possible ways of describing quantum mechanics mathematically. There's really nothing to remove, is there?

> My understanding is that "Wave function collapse" is an artifact of one of the many possible ways of describing quantum mechanics mathematically. The contention seems to be that the Copenhagen interpretation elevates wave function collapse from mathematical artifact to real phenomenon.

Sure, but the Copenhagen interpretation is basically rejected as absurdist and is unnecessary for the exact same reason. It's also trying to give a physical explanation for an artifact of one of the many mathematical representations of quantum mechanics. Schrödinger's Cat is a reductio ad-absurditum to disprove the Copenhagen interpretation!

Re: How Bell’s Theorem proved ‘spooky action at a distance’ is real

#162

Post by naasking »

UncleOxidant wrote: post #144
naasking wrote: post #126

Earlier quoted context omitted.

One is an assertion with no logic to justify it, the other is an assertion with a somewhat persuasive argument justifying it [1]. They are simply incomparable. [1] https://www.simulation-argument.com/simulation.html

But how is the simulation hypothesis not positing a "god" of some sort (some kind of super-intelligence that they claim is behind it all)? It seems like the simulation hypothesis is a theistic hypothesis. Or do they assume the simulation just evolved? Also, why the assumption that post-humans are running the simulations (as in the paper)? Couldn't it be any ultra-advanced civilization that's playing with an evolution…

The simulation argument is exploring the likelihood that post-humans would simulate humans. Both post-humans and humans inhabit a universe with the same laws, so this isn't a fictitious universe created by a deity.

> Also, why the assumption that post-humans are running the simulations (as in the paper)? Couldn't it be any ultra-advanced civilization that's playing with an evolutionary simulation?

Sure, potentially. The paper makes no assumptions about the existence of other life forms, it instead extrapolates the likelihood of a simulation given the only intelligent life we know to exist: us.

Therefore you can see the simulation argument from that paper as a lower bound on the probability we live in a simulation. Positing the existence of other life forms that run random simulations can only increase the probability we're living in a simulation, assuming one of the other outcomes isn't more likely.

Re: How Bell’s Theorem proved ‘spooky action at a distance’ is real

#163

Post by abetusk »

dkersten wrote: post #141
abetusk wrote: post #58

Earlier quoted context omitted.

This is incorrect. What you've described is classical correlation, not quantum correlation.

Would this be correct: You take a marble out of the bag without looking and give the bag to your friend. Your friend also take a marble out of the bag without looking. Both you and your friend now look at your marbles and they will both be the same colour every time. You can't send information this way because you don't know the colour until your friend has already taken a marble too. You cannot do anything with the…

This is, as stated, again classical correlation. Where have you used the fact that the observation of one marble affects the observation of the other?

Your above experiment could be done with just a simple bag and two marbles without the need to contort yourself around looking or not looking.

Here's an attempt to fix your example:

You and your friend each take a marble out of the bag, go very far away from each other and make an agreement to look at the marble at a given time in the future and not before or after. If you look at the marble before or after the agreed upon time, the result will be random. If you both look at it at the exact same time, the marbles will be equal.

Maybe you have many bags of marbles so you can do this experiment many times over. You decide to fudge some results by looking at some marbles before or after the agreed up time. You and your friend will see the same marble color for all marbles seen at the agreed upon time and potentially different marble colors for ones that were opened at different times.

How do you tell if your friend fudged the result? How does your friend tell if you fudged the result? The marbles have a 50-50 distribution of being red and blue, and the extra probability of it flipping to one color or no if it's fudged is lost in that noise.

If you then reconvene and compare notes on what you observed, you can see a very clear correlation of which experiments were fudged and which weren't but now you've done the work of getting in close proximity and destroyed any chance of faster than light communication.

I'm not a physicist and I don't have a deep knowledge of this stuff. This is a toy example and may or may not be a valid reduction of quantum entanglement. The above explanation is my current understanding, which could be wrong.

Re: How Bell’s Theorem proved ‘spooky action at a distance’ is real

#164

Post by feoren »

naasking wrote: post #158
feoren wrote: post #135

Earlier quoted context omitted.

Of the 3 assertions in the abstract, the obviously false one is #2: "Any posthuman civilization is extremely unlikely to run a significant number of simulations of their evolutionary history". When you realize that running a simulation of the universe requires more processing power than is available in the universe, this is very obviously false. I respect people who believe in a bearded White omnipotent homophobic Go…

> Of the 3 assertions in the abstract, the obviously false one is #2: "Any posthuman civilization is extremely unlikely to run a significant number of simulations of their evolutionary history". When you realize that running a simulation of the universe requires more processing power than is available in the universe, this is very obviously false. I think you've expressed a number of confusions. First, I think you co…

Fine, you got me: the assertion that is obviously true, but goes further in that it invalidates the need for any of this discussion. If your goal was to engage me in a thought-measuring contest, sure, you win: you've spent more time thinking about this utterly ridiculous nonsense than I have. Congrats?

Re: How Bell’s Theorem proved ‘spooky action at a distance’ is real

#165

Post by tylerhou »

Kranar wrote: post #66
tylerhou wrote: post #56

Earlier quoted context omitted.

> Rather, both balls are in a superposition of being both red and blue simultaneously, and it is not possible in principle to assign a color to either one of them until the moment a measurement is made. I don't disagree, and (clearly) I make a measurement when I show you the color of a ball. Before I show you a ball, I would also say that the colors of the balls are in a superposition. > major revolution in physics i…

Fair enough we'll simply disagree on that. Entanglement is not a property about wave functions and really has nothing to do with waves. It's a logical consequence of the uncertainty principle and was ironically deduced by Einstein, Rosen, and Podolsky (EPR Paradox) as a way to argue that quantum mechanics is an incomplete description of physical reality. Being that it's strictly a consequence of the uncertainty princ…

> Entanglement is not a property about wave functions and really has nothing to do with waves. It's a logical consequence of the uncertainty principle...

I don't follow, and I can't find anything online that makes this claim. Could you explain more?

Maybe we disagree about the definition of entanglement. I'll take one from Griffith's Introduction to Quantum Mechanics. On page 422, Griffith writes [1]:

> An entangled state [is] a two-particle state that cannot be expressed as the product of two one-particle states....

(There is no mention of uncertainty in this section either.) Here I read "state" to mean "wave function" which implies that entanglement is a statement about a wave function, as I earlier claimed. "Cannot be expressed as a product" means not independent, just like the balls in my analogy (or electrons from neutral pion decay).

When I say "see the color of one ball," I am collapsing the wave function of the balls by making an observation (in the Copenhagen interpretation). This is analogous to measuring an electron's spin. If you replace "ball" with "electron," "bag" with "decay of a neutral pion", "red/blue" with "spin up/down," and "see the color of one ball" with "measure the spin of one electron," that's a completely valid statement in QM.

[1] https://notendur.hi.is/mbh6/html/_downloads/introqm.pdf

Re: How Bell’s Theorem proved ‘spooky action at a distance’ is real

#166

Post by SigmundA »

ericb wrote: post #3

If we were in a simulation, would the speed of light be the processing speed of the universe as each area re-renders, and spooky action at a distance be two variables pointed to the same memory location, populated with a lazy-loaded value, with copy-on-write semantics? edit: seems like it is lazy loaded, so revised my summary.

Speed of light would just be rule, like cellular automata rules, Planck distance is cell size and the rule is you may only move one cell per frame in any direction. Processing speed doesn't matter to us, it could take a million "years" to render a frame but we experience it in real-time.

As you say pointer to shared memory location is basically hidden variable theory, you could also move faster than the speed of light by simply updating your location to any value, I have done this in game hacking before you just need a WriteProcessMemory api, might get caught by anti-cheats.

Re: How Bell’s Theorem proved ‘spooky action at a distance’ is real

#167

Post by naasking »

feoren wrote: post #164
naasking wrote: post #158

Earlier quoted context omitted.

> Of the 3 assertions in the abstract, the obviously false one is #2: "Any posthuman civilization is extremely unlikely to run a significant number of simulations of their evolutionary history". When you realize that running a simulation of the universe requires more processing power than is available in the universe, this is very obviously false. I think you've expressed a number of confusions. First, I think you co…

Fine, you got me: the assertion that is obviously true , but goes further in that it invalidates the need for any of this discussion. If your goal was to engage me in a thought-measuring contest, sure, you win: you've spent more time thinking about this utterly ridiculous nonsense than I have. Congrats?

If you're not interested in philosophical discussions, then why engage at all, particularly only to denigrate people who like exploring thought experiments?

Re: How Bell’s Theorem proved ‘spooky action at a distance’ is real

#168

Post by suzzer99 »

naasking wrote: post #158
feoren wrote: post #135

Earlier quoted context omitted.

Of the 3 assertions in the abstract, the obviously false one is #2: "Any posthuman civilization is extremely unlikely to run a significant number of simulations of their evolutionary history". When you realize that running a simulation of the universe requires more processing power than is available in the universe, this is very obviously false. I respect people who believe in a bearded White omnipotent homophobic Go…

> Of the 3 assertions in the abstract, the obviously false one is #2: "Any posthuman civilization is extremely unlikely to run a significant number of simulations of their evolutionary history". When you realize that running a simulation of the universe requires more processing power than is available in the universe, this is very obviously false. I think you've expressed a number of confusions. First, I think you co…

If the computer code running this simulation is that good to never have bugs, then the simulation is functionally identical to the meatspace real universe from our POV. So I don't know if there's any point thinking about it other than idle curiosity. But I do worry that for some simulation believers it could become an excuse to have less empathy towards fellow humans.

Re: How Bell’s Theorem proved ‘spooky action at a distance’ is real

#169

Post by UncleOxidant »

dntrkv wrote: post #156
UncleOxidant wrote: post #124

Earlier quoted context omitted.

It's kind of interesting how people who would never consider a creationist explanation seem quite willing to embrace the idea that we're in a simulation.

Well, in my case, I don't believe our universe is a simulation, but I'm open to discussing the idea for fun and it does seem like a possibility. Whereas, most people that believe in creationism, believe it 100% to be the case and if you don't believe the same you are going to hell. I grew up in an evangelical Christian community and you can't really compare the two groups. Evangelicals are ready to die for this belie…

This is mostly the YECs (Young Earth Creationist - "the earth is 6000 years old" camp). There are other flavors like ID (Intelligent Design) that tend to hold things a good bit looser - and there are many different flavors of ID as well. But yeah, the YEC folks are completely "it's our way or the hellway!" and the Evangelicals have pretty much doubled down on YEC - that wasn't always the case, there used to be a lot of Evangelicals that were theistic evolutionists and had no problem with a 4.5B year old earth.

EDIT: maybe we need another word in this context besides 'creationist' since it has a lot of baggage in the culture at this point. What else to call someone who hypothesizes that there is some kind of intelligence behind the universe? The simulationists seem to fit into that category as do the various flavors of 'creationist', 'intelligent design', 'theistic evolutionist' and probably even Hindus, etc.

Re: How Bell’s Theorem proved ‘spooky action at a distance’ is real

#170

Post by cepie »

serverholic wrote: post #149
feoren wrote: post #135

Earlier quoted context omitted.

Of the 3 assertions in the abstract, the obviously false one is #2: "Any posthuman civilization is extremely unlikely to run a significant number of simulations of their evolutionary history". When you realize that running a simulation of the universe requires more processing power than is available in the universe, this is very obviously false. I respect people who believe in a bearded White omnipotent homophobic Go…

Isn't it possible that our universe is really just an approximation meant to look as detailed as possible? You don't need a universe of processing power to simulate a universe. You just need to make it look believable enough that it fools whoever is in your simulation.

I agree with you, and even if it's not an approximation, it doesn't matter; we can't make assumptions about the size of a parent reality (and its limits on processing power) relative to our own.
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