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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

#121

Post by joe_the_user »

IncRnd wrote: post #118
joe_the_user wrote: post #113

Earlier quoted context omitted.

There are no propositions that "we are in simulation" would imply (unless someone fundamentally lacks imagination). Being "in a simulation" doesn't imply that we're in simulation created by later humans, it doesn't give any indication how fine-grain the approximations are, etc. etc. "We're in a simulation" fundamentally discard Occam's Razor in the fashion of the belief in God as controlling everything. And thus this…

> "We're in a simulation" fundamentally discard Occam's Razor in the fashion of the belief in God as controlling everything. And thus this belief has the same weight as belief in the Flying Spaghetti Monster [1]. You are using Occam's Razor incorrectly. A preference for parismony in problem solving is not identical with parsimony being the only state of the world. As a side note, which directly applies to your commen…

You are using Occam's Razor incorrectly. A preference for parismony is not identical with parsimony being the only state of the world.

"Everything is really under control of invisible stuff" make it impossible to use parisomy under any circumstances. It fundamentally discards Occam's Razor.

Occam's Razor was invented by Friar William of Ockham as a defense of divine miracles.

While I wouldn't personally accept a God that acts in the world, the argument is about having some sort of evidence based interpretation of the world. Flying Spaghetti Monster is response to arguments like "God makes the rain fall" etc, not to a God that appears in the world but a God that can essentially be evoked for anything and in any fashion.

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

#122

Post by gus_massa »

lisper wrote: post #82
jfengel wrote: post #71

Earlier quoted context omitted.

I don't think the paper justifies the statement as you put it, though perhaps you can point out what I'm missing. I don't think you can tell just from looking at the particle itself whether it has an entangled partner somewhere in the universe. It is, however, possible to use the entangled partners to create systems with decidedly counter-intuitive properties that change the way the un-involved partner interacts. Tha…

See section 4.2, and in particular the paragraph that starts "Here's the kicker..." It is true that you can't tell if a single particle is entangled or not. But if you have an ensemble of particles all prepared in the same state then you can tell if that state is entangled or not. Non-entangled (a.k.a. pure) states have a preferred basis that produce self-interference. Entangled (a.k.a.) mixed states do not. (The pur…

I agree with the GP. If you only have a single member of the pair, then you will see the same interference pattern in a double slit experiment than with a not-entangled particle.

It doesn't matter if the other particle has collided with a brick, went thru a double slit experiment, went thru a bad double slit experiment, or is flying to Andromeda.

(In spite that the calculation to get the correlation with any result in the other experiment may be much harder with the entangled pair than with two non entangled particles.)

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

#123

Post by abetusk »

mmaroti wrote: post #103
abetusk wrote: post #53

Earlier quoted context omitted.

Let's say particles have a 'direction angle' that we can measure with a detector that only gives 'up' or 'down' relative to a direction angle measurement. We can change this direction angle measurement with a knob to set what the measured 'up' and 'down' answers are relative to the detector's direction angle. Further let's say particles can be quantum entangled so that when when two detectors are placed very far apar…

I think you need more assumptions. This satisfies your requirements: X(0) = 0000, Y(a) = 0001, X(a) = 0011, Y(2a)= 0111.

|X(0) - X(a)| = 2, not 1 and X(a) != Y(a)

The subtler issue is that it's a counterfactual question. What would have happened if I had measured or been able to measure all three angles 0, a, 2a? In this case the bit string is the same except for the 1% difference. In other words, X(t) = Y(t), for all t.

The argument is essentially trying to construct a "hidden variable" model and showing that it can't work.

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

#124

Post by UncleOxidant »

joe_the_user wrote: post #113
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.

There are no propositions that "we are in simulation" would imply (unless someone fundamentally lacks imagination). Being "in a simulation" doesn't imply that we're in simulation created by later humans, it doesn't give any indication how fine-grain the approximations are, etc. etc. "We're in a simulation" fundamentally discard Occam's Razor in the fashion of the belief in God as controlling everything. And thus this…

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.

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

#125

Post by naasking »

kolinko wrote: post #24
tylerhou wrote: post #20

Earlier quoted context omitted.

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…

The analogy you mentioned is exactly the wrong one - it suggest that it’s just a matter of a hidden variable. A proper (but less elegant) would be: you have two balls with the same color or a pattern. You take one out. If you check the color first, you will find the other’s color the same, but the pattern sometimes different. If you check the pattern first, you will find the pattern the same, but the color sometimes…

> The analogy you mentioned is exactly the wrong one - it suggest that it’s just a matter of a hidden variable.

It is equivalent to a hidden variable, just a non-local one.

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

#126

Post by naasking »

UncleOxidant wrote: post #124
joe_the_user wrote: post #113

Earlier quoted context omitted.

There are no propositions that "we are in simulation" would imply (unless someone fundamentally lacks imagination). Being "in a simulation" doesn't imply that we're in simulation created by later humans, it doesn't give any indication how fine-grain the approximations are, etc. etc. "We're in a simulation" fundamentally discard Occam's Razor in the fashion of the belief in God as controlling everything. And thus this…

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.

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

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

#127

Post by mrkstu »

joe_the_user wrote: post #121
IncRnd wrote: post #118

Earlier quoted context omitted.

> "We're in a simulation" fundamentally discard Occam's Razor in the fashion of the belief in God as controlling everything. And thus this belief has the same weight as belief in the Flying Spaghetti Monster [1]. You are using Occam's Razor incorrectly. A preference for parismony in problem solving is not identical with parsimony being the only state of the world. As a side note, which directly applies to your commen…

You are using Occam's Razor incorrectly. A preference for parismony is not identical with parsimony being the only state of the world. "Everything is really under control of invisible stuff" make it impossible to use parisomy under any circumstances. It fundamentally discards Occam's Razor. Occam's Razor was invented by Friar William of Ockham as a defense of divine miracles. While I wouldn't personally accept a God…

"we're in a simulation" is at least something that might be ultimately testable with the right theory and experiment. FSM/God isn't w/o them choosing to 'reveal' themselves to everyone.

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

#128

Post by tylerhou »

tsimionescu wrote: post #86
tylerhou wrote: post #52

Earlier quoted context omitted.

Bell's inequality (as you allude to) describes how transformations on quantum wave functions cannot behave classically. But classical wave functions can certainly be entangled as entanglement is a property of a wave function, not transformations on wave functions.

I'm not sure what you mean by classical wave functions - I've only seen the term 'wave function' used for quantum mechanics. Are you referring to classical wave equations? I'm not sure how the concept of entanglement is supposed to apply to classical waves though.

I'm saying that you can represent probability distributions of classical objects as a "wave function."

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

#129

Post by IncRnd »

joe_the_user wrote: post #121
IncRnd wrote: post #118

Earlier quoted context omitted.

> "We're in a simulation" fundamentally discard Occam's Razor in the fashion of the belief in God as controlling everything. And thus this belief has the same weight as belief in the Flying Spaghetti Monster [1]. You are using Occam's Razor incorrectly. A preference for parismony in problem solving is not identical with parsimony being the only state of the world. As a side note, which directly applies to your commen…

You are using Occam's Razor incorrectly. A preference for parismony is not identical with parsimony being the only state of the world. "Everything is really under control of invisible stuff" make it impossible to use parisomy under any circumstances. It fundamentally discards Occam's Razor. Occam's Razor was invented by Friar William of Ockham as a defense of divine miracles. While I wouldn't personally accept a God…

> "Everything is really under control of invisible stuff" make it impossible to use parisomy under any circumstances. It fundamentally discards Occam's Razor.

You are fundamentally misunderstanding Occam's Razor. It is not a law - Occam's Razor is a preference for how to view the world, not a law that was violated. [1]

There are alternate rules-of-thumb, such as one by Ockham's contemporary, Walter Chatton. Chatton created Chatton's anti-razor in opposition to Ockham's Razor: "Consider an affirmative proposition, which, when it is verified, is verified only for things; if three things do not suffice for verifying it, one has to posit a fourth, and so on in turn [for four things, or five, etc.]. (Reportatio I, 10–48, paragraph 57, p. 237)" [2]

[1] https://plato.stanford.edu/entries/ockham/#OckhRazo

[2] https://plato.stanford.edu/entries/walter-chatton/#AntiRazo

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

#130

Post by feoren »

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…

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 law to say that? There must be more to it than that.

There has to be some observation that would be different in a universe with entanglement than in a universe without entanglement, and you haven't described what that difference is. There must be one out there, though -- it's just not clear to me what it is. Does it have to do with the fact that the fastest I can spread the message "I just looked at ball A and it's red!" is the speed of light, and ball B could be very very far away? But I thought entanglement doesn't actually allow FTL communication?

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