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

quantamagazine.org

171–180 of 356 posts

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

#171
post #130

Earlier quoted context omitted.

While I believe that entanglement is genuinely something new and interesting, your explanation of it simply feels like a semantic difference. There is no way in which the universe you describe would be different from a classical universe, at least up to the limits of your description. I'm simply "not allowed" to say that one of the balls is red and the other is blue, before I've looked? It's just, what, against the l…

Isn't this distinction exactly what the article is about? By saying ahead of time, "one ball is red, the other is blue", you're describing a hidden-variables theory of entanglement. It may be unknowable (before measurement) which color the ball in your left hand is, but it has a color. But Bell's theorem provides a very measureable counterexample to this type of explanation of entanglement. Sure, in the article they…

> By saying ahead of time, "one ball is red, the other is blue", you're describing a hidden-variables theory of entanglement.

No, consider the case of neutral pion decay, which emits one spin up electron and one spin down electron. We can clearly say ahead of time one electron will be spin up, and the other will be spin down. But there is no hidden variable that determines which.

If there were a hidden variable, then knowledge of that hidden variable would let you predict which electron is spin up (which ball was red). In the macroscopic world, the hidden variable might be the state of my brain when it chose which hand to grab which ball. But if you replaced me with a robot, and that robot used the measurement of a quantum event (such as an electron's spin) to determine which ball to choose, then there is no hidden variable.

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

#172

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…

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.

> So I don't know if there's any point thinking about it other than idle curiosity.

Idle curiosity is drives a lot of human behaviour, particularly in philosophy!

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

#173
post #159

Earlier quoted context omitted.

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…

If a simulation exists, and there is evidence of it, then sure we could surmise that someone created the simulator - and would have some evidence of such? I think the parent poster was noting that it is a pretty fundamentally different argument than say, positing the existence of a creator, because we exist at all - and that said creator has certain specific requirements of us regarding what we do on Sundays, for ins…

> and that said creator has certain specific requirements

Is that a requirement of every flavor of creationism? Actually, maybe I shouldn't use 'creationism' in this context because that's a loaded term with a lot of baggage at this point. What else to call a hypothesis that asserts there's some kind of intelligence behind the universe that we see? Simulationists would seem to fall into that broader category as would old-school creationists.

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

#174
post #164

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?

I bet you could make your points without insulting others. What do you think?

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

#175
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 ligh…

> Processing speed doesn't matter to us, it could take a million "years" to render a frame but we experience it in real-time.

This is part of the premise of the fantastic novel "Permutation City" by Greg Egan.

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

#176
post #13

Earlier quoted context omitted.

That's not a bad analogy, but you have to be very careful here because no classical analogy can be a perfect fit for entanglement. The wave function is deeply and fundamentally different than our classical reality, and there is no way to reproduce its behavior classically. Among the fundamental differences is the fact that classical information can be copied but quantum states cannot be cloned. This is IMHO the singl…

A classical analogy for entanglement: suppose I have two balls in a bag. They are identical in every way, except one is red and the other is blue. I randomly grab one in each hand and show my hands closed. Now the states of the ball are entangled: as soon as you see the color of one ball, that "determines" the color of the other. (Not claiming that this is a perfect analogy, but I don't see where it diverges from how…

In this case this analogy is very bad because what your describing is an 'hidden local variables'..

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

#177
post #13

Earlier quoted context omitted.

That's not a bad analogy, but you have to be very careful here because no classical analogy can be a perfect fit for entanglement. The wave function is deeply and fundamentally different than our classical reality, and there is no way to reproduce its behavior classically. Among the fundamental differences is the fact that classical information can be copied but quantum states cannot be cloned. This is IMHO the singl…

A classical analogy for entanglement: suppose I have two balls in a bag. They are identical in every way, except one is red and the other is blue. I randomly grab one in each hand and show my hands closed. Now the states of the ball are entangled: as soon as you see the color of one ball, that "determines" the color of the other. (Not claiming that this is a perfect analogy, but I don't see where it diverges from how…

This is exactly the analogy that Bell's Theorem refutes!

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

#178
post #148
post #130

Earlier quoted context omitted.

While I believe that entanglement is genuinely something new and interesting, your explanation of it simply feels like a semantic difference. There is no way in which the universe you describe would be different from a classical universe, at least up to the limits of your description. I'm simply "not allowed" to say that one of the balls is red and the other is blue, before I've looked? It's just, what, against the l…

Ah, but that’s the tough part - there IS a measurable difference in behavior of the universe between these two examples! (albeit hard to experimentally prove exists, but it has been!) They really are in a superposition, not just ‘not known’ until one is measured. Just like light was proven to (truly, actually) be both a light and a wave through the double slit experiments. It doesn’t feel right, but it is - and that…

It could also be that we simply don’t understand something about light phase, and that’s causing us to get confused about superpositions. After all, the experiments aren’t on single photons, they are on beams of photons.

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

#180

Earlier quoted context omitted.

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 ligh…

> Processing speed doesn't matter to us, it could take a million "years" to render a frame but we experience it in real-time. This is part of the premise of the fantastic novel "Permutation City" by Greg Egan.

I read Diaspora which touches on that as well, I really need to read Permutation City.
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