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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

#301

Post by morpheos137 »

intrbelle wrote: post #280
morpheos137 wrote: post #87

Earlier quoted context omitted.

I don't know what you mean. The number of atoms involved in the free will delusion is infintesimal compared to the number of atoms in the universe. Number of atoms in 8 billion human brains: about 10^35 number of atoms in the universe about 10^82 according to search results. Maybe there are no aliens but homo sapiens are just the first stage of the universe becoming self aware.

You shouldn't even bother responding to the person that's claiming to be a research scientist in his/her profile and while he/she wrote such garbage at an attempt to justify such nonsense. HN is overcroweded with people that are against the notion of free will being an illusion. Even dang has a bias. All comments like yours just get unfairly downvoted until they're not visible.

Yeah there is definite a SF hippie/beat woo vibe here at times. Maybe "consciousness" is fundamental and free will is real but so far we haven't see any evidence. I think superdeterminism is more parsiminous than multiple universes.

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

#302

Post by GoblinSlayer »

fungiblecog wrote: post #233
georgeecollins wrote: post #228

Earlier quoted context omitted.

It is also strange, but I think the many worlds hypothesis makes the most sense to me. Then there is no spooky action at a distance, the observer is just always in a particular version of reality that all states, even distant ones, conform to. I am not a physicist!

But there is still spooky splitting of the universe... Many worlds just replaces one mystery with another

It's not a mystery, it has a testable precise mathematical description - Schrodinger equation.

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

#303

Post by GoblinSlayer »

danbruc wrote: post #213
tbabb wrote: post #200

Earlier quoted context omitted.

The distinction between "adding" and "removing" a postulate is an important, non-arbitrary one. The "worlds" are there in both theories; Copenhagen adds a new phenomenon (non-unitary evolution) which makes some of them disappear at unspecified times. The "worlds" are direct consequences of suppositions shared with Copenhagen . Many worlds has N postulates, Copenhagen has no fewer than N+1. One theory is a strict subs…

I think it is not as simple as counting the number of postulates. The ultimate arbiter is physical reality and that decides whether removing or adding postulates is what brings you into agreement. The fact that the quantum state in some equation before wave function collapse looks like many worlds say nothing whether you should take this at face value or whether you are missing an additional postulate that gives you…

Copenhagen sort of agrees with observation by introducing non-locality, which disagrees with observation of locality from other observations, which means Copenhagen disagrees with observation.

>But just because it is an additional postulate it does not per se make many worlds the better theory.

The postulate of collapse contradicts the postulate of Schrodinger equation and makes the system of postulates contradictory. By removing the contradiction MWI is strictly better, this in turn also removes non-locality and achieves a strictly better agreement with observation, like special theory of relativity.

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

#304

Post by tsimionescu »

tylerhou wrote: post #128
tsimionescu wrote: post #86

Earlier quoted context omitted.

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."

So basically a box with two colored balls could be described by a "classical wave functions" (a real-valued wave function), where the values of the two balls are entangled, and then yes, your experiment would exactly describe what happens.

But this sheds no light on quantum wave functions and quantum entanglement.

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

#305

Post by nwallin »

tbabb wrote: post #239
nwallin wrote: post #227

Earlier quoted context omitted.

The problem with interjecting an implication that many worlds is true (regardless of how persuasive the arguments in its favor are) into a layperson's explanation of why quantum entanglement doesn't permit FTL communication are threefold: 1. It doesn't have anything to do with the topic at hand. It is, at best, a distraction. 2. It is impossible to design an experiment which is capable of distinguishing between a uni…

> It doesn't have anything to do with the topic at hand. To the contrary, it provides an intuitive model that produces correct predictions. That is inherently valuable and extremely relevant. > Arguing about Copenhagen vs many worlds is literally no different than arguing about Jesus vs Mohamed. Strongly disagree— See further discussion[1] under my original post for support. > You guarantee that everybody is going to…

> it provides an intuitive model

Uh. No. It definitely -- definitely -- doesn't do that. Many worlds, for all its many virtues, gives us "There's another dimension where you -- you -- are Batman!" Because that's what the phrase "many worlds" means to most people.

> > Arguing about Copenhagen vs many worlds is literally no different than arguing about Jesus vs Mohamed.

> Strongly disagree— See further discussion[1] under my original post for support.

So in that discussion, you made the argument:

> Both models agree with observation— any measurement we make will not contradict either "empty garage" or "undetectable dragon".

...which is literally the argument people make when they're arguing Jesus vs Mohamed. It's just that nobody agrees on which holy being is the empty garage and which one is the undetectable dragon.

> Not wrong >_>

Woooo! I won an argument on the internet!!

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

#306

Post by tsimionescu »

feoren wrote: post #132
tsimionescu wrote: post #39

Earlier quoted context omitted.

The problem with your classical analogy for entanglement is that it doesn't match the data. Or rather, it only matches the data for quantum properties that are similarly blue or red. The non-classical properties of entanglement start appearing once you start measuring combinations of the redness and blueness of those balls. Let's say that instead of looking at the balls, you pass them through some machine that will l…

This is a great thought experiment, thank you. I'm not totally clear how the machines could work without actually taking a measurement, though. It sounds like you're saying the 2nd machine (P = 0.5) takes measurements (and therefore "paints" the balls), but the other two don't? I've heard of the apocryphal "half-silvered mirror", but I don't get why reflection isn't an observation/interaction there either.

> I'm not totally clear how the machines could work without actually taking a measurement, though.

Here you're hitting on the heart of the Measurement Problem. In QM as it is understood today, unlike classical mechanics, there are two fundamentally different kinds of interactions between objects: quantum interactions and measurement. Quantum interactions are linear changes to the wave function, while measurements perform a non-linear update to the wave function (it becomes one for the measured value and 0 everywhere else).

Unfortunately, we do not have any theory so far that explains what is the difference between a quantum interaction and a measurement. The experiment I described works with 'machines' that interact quantically with the 'balls', but does not reproduce if the machines measure the state of the balls.

I will note that in the Many Worlds Interpretation, the measurement problem is somewhat different - it states that the state of the universe is always described by a wave function, but that parts of the wave which are sufficiently separated can no longer perceive each other somehow, usually called branching. Precisely when, why or how this happens are just as unknown, though decoherence seems to play a role

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

#307

Post by GoblinSlayer »

lisper wrote: post #212
feoren wrote: post #132

Earlier quoted context omitted.

This is a great thought experiment, thank you. I'm not totally clear how the machines could work without actually taking a measurement, though. It sounds like you're saying the 2nd machine (P = 0.5) takes measurements (and therefore "paints" the balls), but the other two don't? I've heard of the apocryphal "half-silvered mirror", but I don't get why reflection isn't an observation/interaction there either.

> I don't get why reflection isn't an observation/interaction there either. I know this comment is going to get lost in the noise, but that is a really excellent point, one of the best that has been raised here so far. This is a point that is often glossed over, but it is actually really important, and quite challenging to explain without getting deep into the weeds. The answer is that passing through a half-silvered…

The reflection does affect the state of a macroscopic system - mirror, as momentum of the reflected photon changed and needs to conserve.

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

#308

Post by GoblinSlayer »

tsimionescu wrote: post #306
feoren wrote: post #132

Earlier quoted context omitted.

This is a great thought experiment, thank you. I'm not totally clear how the machines could work without actually taking a measurement, though. It sounds like you're saying the 2nd machine (P = 0.5) takes measurements (and therefore "paints" the balls), but the other two don't? I've heard of the apocryphal "half-silvered mirror", but I don't get why reflection isn't an observation/interaction there either.

> I'm not totally clear how the machines could work without actually taking a measurement, though. Here you're hitting on the heart of the Measurement Problem. In QM as it is understood today, unlike classical mechanics, there are two fundamentally different kinds of interactions between objects: quantum interactions and measurement. Quantum interactions are linear changes to the wave function, while measurements per…

They don't perceive each other when they evolve independently, i.e. when they are valid solutions of the schrodinger equation.

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

#309

Post by GoblinSlayer »

samecouldbesaid wrote: post #299
GoblinSlayer wrote: post #297

Earlier quoted context omitted.

As I understand, superdeterminism isn't the same as determinism. Normally Bell's theorem would tell you that it's determinism, but a deterministic system still can arbitrarily end up with skewed statistics and thus look like anything and you can't expose it because it's skewed in a specific way. That's superdeterminism, it looks like not what it is by pure chance.

Superdeterminism is still determinism but an idea added to it for all particles sharing all future states. Superdeterminism is against the idea of real-time processing while Quantum Mechanics is typically imagined as real-time processing. Sure, determinism can illustrate a deterministic system producing infinite universes that are deterministically operating every possibility imaginable, where a local subject could g…

In any determinism all particles share all future states simply because future states are predictable and there's only one future, which is total statistical correlation. In superdetermininsm these future states aren't any states, but particularly selected states that show skewed picture. And they ended up this way arbitrarily, which is a chance (maybe bayesian).

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

#310

Post by GoblinSlayer »

Zamicol wrote: post #68

If you "measure" the bits per character in the base 45 alphanumeric encoding used in QR code, you'd get 5.5 bits per character as 11 bits is used for two characters. How is it possible to have information less than a bit, a partial bit? What is that ".5" part? Isn't a bit indivisible? Only in the context of a character doublet is all information expressed. To know the "half bit" part, you cannot "look" at just one ch…

A bit here is a unit of amount of information, not a physical bit in silicon.
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