What do violations of Bell's inequalities tell us about nature?

[bohm2]

Please vote and if possible state the reasons for holding your belief. As a review here are the two major views with quotes by leading physicists in quantum foundations:

1. Observed violations of Bell's inequalities implies that nature is non-local:

In 1964, Bell proved that any serious version of quantum theory (regardless of whether or not it is based on microscopic realism) must violate locality. He showed that if nature is governed by the predictions of quantum theory, the "locality principle," precluding any sort of instantaneous (or superluminal) action-at-a-distance, is simply wrong, and our world is nonlocal.

What is most relevant to Bell's Theorem is that the non-locality which it makes explicit in Quantum Mechanics is a small indication of pervasive ultramicroscopic nonlocality. If this conjecture is taken seriously, then the baffling tension between Quantum nonlocality and Relativistic locality is a clue to physics in the small.

2. Observed violations of Bell's inequalities implies anti-realism (e.g. quantum measurement results do not pre-exist)

...quantum measurement results do not preexist in any logically determined way before the act of measurement.

...unperformed tests have no outcomes: it is wrong to try to account for the outcomes of all the tests you might have performed but didn’t.

 

[VantagePoint72]

This is a bizarre question. Violations of Bell's inequalities just tell us that at least one of (1) and (2) must be true. It doesn't prefer one or the other, nor does it rule out both of them being true (as is the case in the Copenhagen interpretation). Various people may well have preference for either anti-realism or non-locality but that preference can't possibly come from Bell's theorem alone. It's complete nonsense to say, "Observed violations of Bell's inequalities implies that nature is non-local," or, "Observed violations of Bell's inequalities implies anti-realism." Observed violations of Bell's inequalities imply neither.

Either you're misunderstanding Bell's theorem, or you did an extremely poor job of phrasing your question.

 

[VantagePoint72]

Also, your "other" category seems very confused. Alternative interpretations of QM are not exempt from having to deny either locality or counterfactual definiteness. Many worlds, for instance, does the latter.

 

[bohm2]

Either you're misunderstanding Bell's theorem, or you did an extremely poor job of phrasing your question.

The exact same question was posed to leading experts in quantum foundations in this book here (see chapter 8). I'm interested in how people on this forum would respond. Some of those quotes come from that book chapter:

Elegance and Enigma: The Quantum Interviews
https://www.amazon.com/dp/3642208797/?tag=pfamazon01-20

 

[Maui]

There are different interpretations, but generally violations of Bell's inequalities imply what's already known - that classical mechanics(strict materialism) is just one aspect of reality and so no longer an adequate explanation of observations. As Heisenberg once put it/quoted by Nick Herbert in Quantum Reality/:

"The ontology of materialism rested upon the illusion that the kind of existence, the direct 'actuality' of the world around us, can be extrapolated into the atomic range. This extrapolation, however, is impossible... atoms are not things."

The way to keep the strict materialism intact is by accepting a small conspiracy - superdeterminsim or hidden variables(or to deny interest into the inner workings of reality).

 

[bohm2]

The way to keep the strict materialism intact is by accepting a small conspiracy - superdeterminsim or hidden variables(or to deny interest into the inner workings of reality).

I don't think anybody has ever given a good definition of "materialism". Do you have one? And why do you think that a non-local, "realistic" model would still be considered "materialistic"?

 

[DennisN]

I voted "anti-realism". My reasons/opinions are:

• "Nature is non-local"; I wouldn't accept this without an underlying mechanism which describes it.
  
• "Other: Superdeterminism, backward causation, many worlds, etc"; I can't see how any of these interpretations would be falsifiable, and this makes me doubt their scientific value.

Therefore I lean towards "anti-realism". I am however pretty agnostic, and my views could change depending on future science and experiments. I would have preferred to vote on a fourth "softer" option; (observed violation of Bell's inequality tell us) there are parts of QM we can't yet fully comprehend/explain.

 

[nanosiborg]

Please vote and if possible state the reasons for holding your belief.

I would vote that violations of Bell inequalities tell us nothing about nature if your poll had that as an option.

Bell's theorem proves that there's no function, ρ(λ), for which this correlation coefficient,
C(a,b) = ∫ ρ(λ) A(a,λ) B(b,λ) dλ , matches Malus' Law (cos²θ) .

The results of Bell tests involving photons entangled in polarization support the generalization of results from classical and quantum wave optics involving crossed polarizers in that the QM treatments of optical Bell test setups are evaluated using Malus' Law.

The results of Bell tests don't reveal anything new regarding fundamental empirically based tenets of wave optics. They certainly don't imply that nature is nonlocal ... though it's tempting to assume that nature is nonlocal by virtue of the fact that nonlocal hidden variable models of quantum entanglement are viable. They also don't imply the "other" option, which, as DennisN pointed out, are all untestable assumptions. For me they're just either meaningless (backward causation, many worlds) or superfluous (superdeterminism) as well. As for anti-realism, it isn't clear to me what is meant by "quantum measurement results do not pre-exist". The measurement results in Bell tests are either detection or nondetection within a coincidence interval. Obviously, these results don't "pre-exist". If it's simply meant that realism (ie., hidden variable accounts, or the existence of hidden variables) is ruled out, then we know that that's false. Realism isn't ruled out.

So, what are we left with? Just that there are hidden parameters operating to produce quantum entanglement stats that remain hidden (ie., unknown) -- and from that it still isn't known whether there is some sort of nonlocality in nature or if nature is evolving exclusively according to the principle of local action. But we do know that formulating models of Bell tests in terms of Bell locality is ruled out. Which means that models of quantum entanglement can't take the form that Bell's locality condition requires them to take.

 

[Nugatory]

I wish you had given us a fourth choice: "abstain, until such time as someone can propose an experiment that could distinguish (a) from (b)". That way my abstention could be recorded

 

[bohm2]

I wish you had given us a fourth choice: "abstain, until such time as someone can propose an experiment that could distinguish (a) from (b)". That way my abstention could be recorded

That's option 3: Other

 

[Nugatory]

Either you're misunderstanding Bell's theorem, or you did an extremely poor job of phrasing your question.

I don't think that's a completely fair criticism (and I say this despite having already complained about the lack of an "abstain" option).

Both locality and realism are so natural and so deeply ingrained in our thinking that once we know we can't have both, it's interesting to ask "if you had to give one up, which would it be?"... And I doubt that many people would join Bohr and answer "lose 'em both!", although that answer certainly is not excluded by Bell experiments or anything else we know.

 

[Nugatory]

That's option 3: Other

No, no, no... I will not cast a vote that might be counted with "superdeterminism, backwards causation, many worlds, etc.". I DEMAND a respectable abstention that allows me to shut up and calculate without committing myself to any position

 

[danR]

I vote for 1. I not only see no reason why quantum behaviour cannot be non-local, I could conjecture that some property/variable of the original universe did not expand with 4-space, which we might call quantum-field, and is a property that particles near the original size of the universe share.

 

[bohm2]

I vote for 1. I not only see no reason why quantum behaviour cannot be non-local, I could conjecture that some property/variable of the original universe did not expand with 4-space, which we might call quantum-field, and is a property that particles near the original size of the universe share.

That was my reason also. It just seems that some "remnant" or "property" of the non-spatial-temporal stuff that gave "birth" to the big bang should still be with us.

 

[DrChinese]

No, no, no... I will not cast a vote that might be counted with "superdeterminism, backwards causation, many worlds, etc.". I DEMAND a respectable abstention that allows me to shut up and calculate without committing myself to any position

I love it. Nugatory is not to be denied...

 

[danR]

That was my reason also. It just seems that some "remnant" or "property" of the non-spatial-temporal stuff that gave "birth" to the big bang should still be with us.

I can't share the "seems...should" part, however. I just offer it as a conjecture: untestable, unfalsifiable.

Having said that, I would metaphysically ask why every single property of the primordial dimensionless point should necessarily be bound to a macroscopic, relativistically-governed spatio-temporal address.

Indeed, isn't the extraordinary part about the universe in that any property of it should have expanded at all? Why didn't it just all stay there in one a/non -local 'place' in the first place?

I asked one of my profs once what was the objection to non-locality was (i.e. "what really upsets you guys about it?"), and with me being an arts major he may have geared his answer to my understanding, and I may have misunderstood it, but it was something along the lines that it just made too many connections between distant objects.

In other words, they don't like non-locality because it sucks.

Well, that's just to bad. In our lectures and assignments and exams (this was a different prof, the first was teaching a more classical topic, though his specialty was quantum gravity) we were required to express confusion, puzzlement and great explanatory power in dealing with, say, two emitted photons; the spin of the one measured in Paris, and the spin of the other measured in Japan.

The wording is perpetually prejudiced toward the idea that two different spins, or spin-attributes, are being measured, instead of just one shared property. Perhaps I'm missing some deeper aspect to the issue that makes non-locality a problem nevertheless.

 

[bohm2]

In other words, they don't like non-locality because it sucks.

Einstein felt the same way:

It is further characteristic of these physical objects that they are thought of as arranged in a space-time continuum. An essential aspect of this arrangement of things in physics is that they lay claim, at a certain time, to an existence independent of one another, provided these objects ‘are situated in different parts of space’. Unless one makes this kind of assumption about the independence of the existence (the ‘being-thus’) of objects which are far apart from one another in space—which stems in the first place from everyday thinking— physical thinking in the familiar sense would not be possible. It is also hard to see any way of formulating and testing the laws of physics unless one makes a clear distinction of this kind. This principle has been carried to extremes in the field theory by localizing the elementary objects on which it is based and which exist independently of each other, as well as the elementary laws which have been postulated for it, in the infinitely small (four-dimensional) elements of space.

Others like Gisin question this preference of non-realism to non-locality, however:

It might be interesting to remember that no physicist before the advent of relativity interpreted the instantaneous action at a distance of Newton’s gravity as a sign of non-realism (although Newton’s nonlocality is even more radical than quantum nonlocality, as it
allowed instantaneous signaling).

Is realism compatible with true randomness?
http://arxiv.org/pdf/1012.2536v1.pdf

 

[DennisN]

Perhaps I'm missing some deeper aspect to the issue that makes non-locality a problem nevertheless.

I don't know, but I could quote Isaac Newton;

"It is inconceivable that inanimate brute matter should, without the mediation of something else, which is not material, operate upon, and affect other matter without mutual contact...[] That gravity should be innate, inherent and essential to matter, so that one body may act upon another at a distance through a vacuum, without the mediation of any thing else, by and through which their action and force may be conveyed from one to another, is to me so great an absurdity that I believe no man who has in philosophical matters a competent faculty of thinking can ever fall into it. Gravity must be caused by an agent acting constantly according to certain laws; but whether this agent be material or immaterial, I have left to the consideration of my readers." (source)

which is a sort of caveat to his law of universal gravitation (his law implies that gravitational force is transmitted instantaneously, which we now understand is not correct). This quote is of course about gravitation, not quantum entanglement. But my point is that many people find it hard (incl. me) to accept any kind of action at a distance without any mediator/medium in between and/or without any mechanism which describes it in more detail. And if the action seems to be instantaneous, it's even worse (considering the finite value of the speed of light). That pretty much sums up my own problems with action at a distance .

(I saw bohm2 already had replied to this while I was writing my reply)

 

[Nugatory]

I find myself wondering which of realism and locality is more "natural" to our thinking, more easily accepted at an intuitive level.

I'm inclined to think that it's realism:
- A cat and a bird are outside watching one either right now... I am quite confident that the biochemical computers that guide their behavior are programmed to analyze the situation in purely realistic terms. I doubt that this bias would change if either were to develop greater capacity for abstract thought.
- People are discouragingly willing to accept magical non-local explanations such as astrology. These non-local magical explanations are generally realistic; the astrologers don't question whether the moon and the planets are there when no one is looking.
- Few people are disturbed by the truly egregious non-locality of Newtonian gravitation; and I expect that most laypeople find Schrodinger's cat more disturbing/confusing/"wrong" than gravitational action at a distance.

Interesting though (at least to me) is that the poll results are running the other direction...

 

[danR]

I don't know, but I could quote Isaac Newton;


which is a sort of caveat to his law of universal gravitation (his law implies that gravitational force is transmitted instantaneously, which we now understand is not correct). This quote is of course about gravitation, not quantum entanglement. But my point is that many people find it hard (incl. me) to accept any kind of action at a distance without any mediator/medium in between and/or without any mechanism which describes it in more detail. And if the action seems to be instantaneous, it's even worse (considering the finite value of the speed of light). That pretty much sums up my own problems with action at a distance .

(I saw bohm2 already had replied to this while I was writing my reply)

I don't see how 'action at a distance' applies to entanglement in quantum world, even by analogy, where/(if) there is no 'action' or 'distance'. Of course ultramicroscopic particles are subject to other properties dependent on space and time. They are 4-space dependent, but quantum-wise non-local. Or to put it less prejudicially (since 'non-local' has the connotation of being somehow defective, deviant, odd), quantum-entanglement has only one locale.

Of course, there are spins that are not entangled, but I could speculate further that all spin-baggage, correlated or not, is permanently stuck in some cosmic LaGuardia airport.

 

[Nugatory]

I don't know, but I could quote Isaac Newton;

true enough... but also worth noting that Newton is something of an outlier here. For every person who has shared Newton's (and many other thinkers') discomfort with action at a distance, probably thousands of people have cheerfully accepted and swallowed the notion.

 

[DennisN]

true enough... but also worth noting that Newton is something of an outlier here. For every person who has shared Newton's (and many other thinkers') discomfort with action at a distance, probably thousands of people have cheerfully accepted swallowed the notion.

True. I have once been one of those thousands of people . But I changed.

 

[Maui]

I don't think anybody has ever given a good definition of "materialism". Do you have one? And why do you think that a non-local, "realistic" model would still be considered "materialistic"?

Materialism would be the old mechanistic concept of reality but this is beside the point. The point is not why there could potentially be non-locality but why there is locality. When you answer that question from the point of view of qm(since this is the quantum theory forum!), then we can know why under certain circumstances non-locality could be observed. People seem to forget(even in this forum) that reality is quantum mechanical and not classical. If you treat classical mechanics as fundamental(not emergent) you get action at a distance, nonlocality, tunneling through barriers, many worlds, backward causation, objects spinning in two directions at the same time and other wonderful phenomena. And people go on to extrapolate all the time the reality of tables and chairs to the quantum realm as if they are somehow interchangeable or compatible.

 

[bohm2]

In hindsight, I'm not sure Gisin's argument that Newton's non-locality is more "radical" is accurate. For instance, quantum non-locality would not also have to be FTL (instantaneous) but would also have to be unattenuated and discriminating as Maudlin and others note:

The quantum connection is unattenuated:

Since the gravitational force drops off as the square of the distance it eventually becomes negligible if one is concerned with observable effects...The quantum connection, in contrast, appears to be unaffected by distance. Quantum theory predicts that exactly the same correlations will continue unchanged no matter how far apart the two wings of the experiment are.

The quantum connection is discriminating:

The effects of the sparrow’s fall ripple outward, diminishing as distance increases, jiggling every massive object in its way. Equally massive objects situated the same distance from the sparrow feel identical tugs. Gravitational forces affect similarly situated objects in the same way...The quantum connection, however, is a private arrangement between our two photons. When one is measured its twin is affected, but no other particle in the universe need be...The quantum connection depends on history. Only particles which have interacted with each other in the past seem to retain this power of private communication. No classical force exhibits this kind of exclusivity.

Quantum non-locality & Relativity
https://www.amazon.com/dp/0631232214/?tag=pfamazon01-20

The point is not why there could potentially be non-locality but why there is locality.

That's a good point.

 

[danR]

Quote by Maui
"The point is not why there could potentially be non-locality but why there is locality."
​

That's a good point. --bohm2

Locality is simply entailed by the original expansion of 4-space, the condensation of matter, and the fractionation of the forces. There's no reason to require that every attribute of the original entity was dragged along with the emergence of locality.

PS: I've now mangled the quotes thoroughly, but hope y'all can sort it out.

 

[rubi]

The "Shut up and calculate" choice is definitely missing. Unless there are some observable differences between different interpretations of QM or unless they make calculations easier, it's a waste of time to think about it. I also don't want to be counted to option #3.

However, if i had to choose between non-locality and anti-realism, i would choose anti-realism, because i don't really see why realism is so desirable apart from the fact that otherwise, one has to give up his beliefs and prejudices about nature that originate from the naive assumption that we can extrapolate the laws of the macroscopic world to the microscopic world as well.

On the other hand i'd rather not give up locality, because that would mean that some events in the andromeda galaxy or even outside the observable universe could in principle influence events on earth, unless you impose some strong limitations on the non-locality in your theory (and if you do so, then you'd have to justify them somehow). That would make physics entirely pointless, because it would mean that our equations would have to depend on parameters that can't be measured here on earth. So even if the world were non-local, it's reasonable to assume that it's not, in order to even be able to write down equations that are of any use.

 

[danR]

On the other hand i'd rather not give up locality, because that would mean that some events in the andromeda galaxy or even outside the observable universe could in principle influence events on earth, unless you impose some strong limitations on the non-locality in your theory (and if you do so, then you'd have to justify them somehow).

Limitations are precisely what are involved. Spin correlation of co-generated photons, for example. Since quantum entanglement is not a mediator of any of the forces, I would want to know what the influence would be.

If Bob measures ↓ here and Alice measures ↑ at the Andromeda galaxy, they are only measuring a single down-up attribute shared (somewhere in nowhere-ville) by two co-generated particles.

 

[DrChinese]

... by two co-generated particles.

Of course that is not a requirement for entanglement, that they are co-generated. They don't even need to interact by conventional means - or even have interacted at all if entanglement swapping is considered.

 

[nanosiborg]

In hindsight, I'm not sure Gisin's argument that Newton's non-locality is more "radical" is accurate. For instance, quantum non-locality would not also have to be FTL (instantaneous) but would also have to be unattenuated and discriminating as Maudlin and others note:
The quantum connection is unattenuated:

Quantum theory predicts that exactly the same correlations will continue unchanged no matter how far apart the two wings of the experiment are.

That QM predicts (and experiment confirms) that quantum entanglement is unaffected by distance is based on the classical conservation laws and empirically based optics principles (eg., Malus' Law). The quantum entanglement correlations (and the idea that distance isn't a factor) aren't unexpected or 'weird' given what's been ported from classical physics and wave optics to the quantum theory.

The quantum connection is discriminating:

...The quantum connection ... is a private arrangement between our two photons. When one is measured its twin is affected, but no other particle in the universe need be...

This is essentially correct, except for the bolded part (and also that the 'private arrangement' need not be between just two particles). In a typical optical Bell test involving paired photons, measurement at one end need not be affecting the photon at the other end in order to produce the observed correlations. There just needs to have been a relationship produced between the motional properties of paired photons. The production of such an entanglement doesn't require that the photons have interacted or that they have a common source.

It's true that ...

The quantum connection depends on history.

... but it's not true, as DrChinese has pointed out, that ...

Only particles which have interacted with each other in the past seem to retain this power of private communication.

The motional properties of entangled particles need only to have undergone some sort of similar modification which produces a measurable relationship between their resulting motions.

In light of the contributions of the classical conservation laws and classical wave optics to the QM treatment of polarization entangled photons, it's maybe a bit misleading to say that ...

No classical force exhibits this kind of exclusivity.

The difference between the sorts of relationships that can be produced in classical preparations and those that can be produced in quantum preparations is one of degree. But the principle is essentially the same. A common origin, interaction, or imparting a common or related motional property to spatially separated particles produces statistical dependence and predictable correlations ... with the underlying fine tuning of quantum entanglement correlations remaining something of a mystery.

Regarding the question of why there is locality, this is similar to the question of why disturbances in media expand more or less omnidirectionally (depending on the properties of the medium in which the disturbance is produced), in that they both might well be unanswerable questions. That is, they both might be irreducibly fundamental properties of physical reality, and as such would form part of the axiomatic structure of a comprehensive theory. Which is sort of the place that the principle of local action, along with causal determinism, has in contemporary physical science. These are (at least tacitly held) assumptions that are required for physical science to have any unambiguously communicable meaning.

The metaphysical speculations about nonlocality, etc. remain just that. If violations of Bell inequalities actually informed regarding nature, well, that would be great. Unfortunately, they don't.
But that doesn't make Bell's theorem 'short-sighted', as another current thread asked. Bell's analysis provides a very clear answer to the question he was asking. Namely, are QM-compatible LHV models of quantum entanglement possible? The answer, mathematically proven, is no, they aren't. If you take Bell's formulation to be generalizable, and I do, then QM-compatible LHV models of quantum entanglement are definitively ruled out. Beyond that, violations of Bell inequalities tell us nothing about nature. If that doesn't do it for you, then you might be talking round and round about this stuff, and getting nowhere, for a really long time.

 

[stevendaryl]

That QM predicts (and experiment confirms) that quantum entanglement is unaffected by distance is based on the classical conservation laws and empirically based optics principles (eg., Malus' Law).

Here's a wild idea that's probably nonsensical, but I wonder if anyone has investigated it: Kaluza-Klein theory introduced the trick of having extra spatial dimensions that are unobservable because they are wrapped into tiny little circles. I'm wondering if there is some topology that can be constructed using extra dimensions, so that, essentially, every point in space is the same, very short, distance from every other point, if one travels in the hidden dimensions. For illustration, imagine a flat sheet of paper, crumpled into a ball and compressed to a tiny volume. Travel within the plane of the paper is unaffected by the crumpling, but the crumpling allows a "short-cut" between any two points, by traveling perpendicular to the plane of the paper.

So I'm wondering if there is a way to understand the "instantaneous" quantum interactions of Bohm theory as interactions that only seem instantaneous because they only travel a short distance.

 

[stevendaryl]

I don't see how 'action at a distance' applies to entanglement in quantum world, even by analogy, where/(if) there is no 'action' or 'distance'.

Well, following the Bohm interpretation of quantum mechanics, the weird statistics is explained through action at a distance via an instantaneous "quantum potential" term in the equations of motion.

 

[nanosiborg]

Here's a wild idea that's probably nonsensical, but I wonder if anyone has investigated it: Kaluza-Klein theory introduced the trick of having extra spatial dimensions that are unobservable because they are wrapped into tiny little circles. I'm wondering if there is some topology that can be constructed using extra dimensions, so that, essentially, every point in space is the same, very short, distance from every other point, if one travels in the hidden dimensions. For illustration, imagine a flat sheet of paper, crumpled into a ball and compressed to a tiny volume. Travel within the plane of the paper is unaffected by the crumpling, but the crumpling allows a "short-cut" between any two points, by traveling perpendicular to the plane of the paper.

Interesting stevendaryl, but I think that whatever you're getting at is way over my head.

So I'm wondering if there is a way to understand the "instantaneous" quantum interactions of Bohm theory as interactions that only seem instantaneous because they only travel a short distance.

In line with danR's statement, I don't think that instantaneous action at a distance is understandable. There's no mechanics, no propagation, no time for any sort of physical interaction. I view it as basically a collection of terms that function as a placeholder for our ignorance and refer to something that happens in the mathematics of a theory.

But it sounds like you might be able to fashion some sort of novel mathematical contrivance or other. Not that that would provide any understanding either, but then mathematical contrivances (and placeholders) don't have to. They just need to help facilitate the calculation of accurate quantitative predictions.

 

[nanosiborg]

Well, following the Bohm interpretation of quantum mechanics, the weird statistics is explained through action at a distance via an instantaneous "quantum potential" term in the equations of motion.

But the statistics aren't weird. They're understandable through the QM incorporation and application of classical laws.

 

[stevendaryl]

But the statistics aren't weird. They're understandable through the QM incorporation and application of classical laws.

They seem pretty weird to me. When you are measuring, for instance, the projection of the spin of an electron on the z-axis, for example, I think it's understandable that the result may be nondeterministic. The measurement process may interact with the electron in an uncontrollable way, and so a deterministic prediction might not be possible. But if that electron is part of an electron-positron twin pair, then it's weird to me that you can tell with absolute certainty that if you measure spin-up in the z-direction, then whoever checks the spin of the positron will find spin-down in the z-direction.

That's the weirdness of quantum randomness--not the randomness by itself, but the combination of randomness with a kind of certainty of the distant correlations.

 

[nanosiborg]

They seem pretty weird to me. When you are measuring, for instance, the projection of the spin of an electron on the z-axis, for example, I think it's understandable that the result may be nondeterministic. The measurement process may interact with the electron in an uncontrollable way, and so a deterministic prediction might not be possible. But if that electron is part of an electron-positron twin pair, then it's weird to me that you can tell with absolute certainty that if you measure spin-up in the z-direction, then whoever checks the spin of the positron will find spin-down in the z-direction.

That's the weirdness of quantum randomness--not the randomness by itself, but the combination of randomness with a kind of certainty of the distant correlations.

So, what can be inferred from the predictability of distant correlations? Can it be said, for example, that there has been an invariant relationship between entangled particles created through the entangling process, ie., through common source, interaction, common motion imparted to particles that don't have a common source and have never interacted, etc.? If so, does this seem weird? It doesn't to me, and the fact that the totality of results of optical Bell tests are in line with the conservation laws and optics principles further supports that view.