Is action at a distance possible as envisaged by the EPR Paradox.

[ThomasT]

Bell's ansatz assumes a locally realistic mechanism must take a form that linearly transitions with the change in angle. What we have is a transition that changes with the square of the angle. Yet this empirical fact is ubiquitous. The same rules apply to polarizers, the efficiency loss in aerial antennas offset from the ideal setting, etc.

It was from evaluations along these lines that suggested to me that there might be something wrong with Bell's formulation. For example, if EPR elements of reality are too restrictively represented, or if the statistical independence represented by Bell's equation (2) supercedes it's represention of causal independence between A and b (B and a), then Bell's formulation isn't logically rigorous, and violations of BIs aren't physically relevant.

This empirical fact may or may not have a realistic basis.

What do you mean by this? That the cos^2 theta rule can't be understood realistically?

But the fact that EPR correlations exhibit the same detection profile says nothing about locality when the same effect occurs without any correlations involved. EPR correlations, in this view, would only indicate the mechanism is deterministically replicable.

This is the way everyone would think about it in the absence of interpretations of Bell to the contrary. And, this is why it's so important to continue to examine the assumptions underlying Bell's formulation. A couple of generations of professionals in the field going back and forth on what BI violations mean is reason enough to think that it's just possible that some subtle point which would render Bell's theorem physically irrelevant (except for it's possible application as an indicator of the presence and degree of entanglement) has been glossed over.

Here is an interest paper by Michael Seevinck, which rigorously derives a version of Bell's inequalities for correlations.
The Quantum World is Not Built Up From Correlations.
Found. Phys. 36, 1573-1586 (2006)

I just briefly looked at this so far, but it would seem to support the idea that the nature of entanglement is relationships between and among things. Not things in themselves. Whether or not we see entanglement depends on how we look at things. Hence the nonseparability of the relationship between (the relationship between) the things being observed and the observational context. Which Bell doesn't quite capture in his LR ansatz.

 

[DrChinese]

It was from evaluations along these lines that suggested to me that there might be something wrong with Bell's formulation. For example, if EPR elements of reality are too restrictively represented, or if the statistical independence represented by Bell's equation (2) supercedes it's represention of causal independence between A and b (B and a), then Bell's formulation isn't logically rigorous, and violations of BIs aren't physically relevant.

If you are going to make statements like this, you had better back it up.

So perhaps you can give me an example if how a) EPR elements of reality are too restrictive; b) a classical case in which Bell's (2) is violated when considering the full universe.

In other words, what is wrong with Bell's definitions (other that you don't like the conclusions they inevitably lead to) ?

 

[ThomasT]

They most certainly ARE polarization clones of each other. And they are entangled. But they are not polarization entangled, which is quite different.

How do we know that they're polarization clones of each other if they don't produce entanglement stats?

Also, if

...the only difference in producing the entangled state versus the product state is a small rotation of a wave plate.

That wouldn't seem to indicate that they're "quite different", unless we are to assume that a "small rotation of a wave plate" somehow switches on some sort of action at a distance or ftl communication between the photons.

If we accept your physical assumption of "counter-propagating influences", then these should produce the same statistics as entangled particles. But they don't.

The fact that a wave plate rotation is required to produce polarization entanglement would seem to indicate that they weren't clones of each other to begin with. Or, maybe the wave plate rotation keeps them cloned but adjusts some other parameter which then results in entanglement. Or, maybe the wave plate rotation unclones them, and then, since they're uncloned they have to communicate via action at a distance or ftl to be 'entangled'.

Now why are these particles acting different? Because they are NOT in a superposition of polarization states. This is meaningful within QM but has no counterpart in a local realistic theory - in which there is no such thing as a superposition (by definition).

I think we both agree that (1) quantum superposition and quantum entanglement can't be understood in terms of separable (factorable) combinations of the individual systems. However, contrary to (1), (2) Bell (via a certain interpretation of the scope of EPR's definition of reality) has required LR models of entanglement to be represented in a separable form which contradicts the reality of the experimental situations to which that form is being applied. The paper that you referenced agrees with (1). So does every other paper I've read on this. I haven't found anything yet that specifially addresses (2), except for viable LR models that, in agreement with (1), encode the fact that joint detection is determined by different parameters than those which determine individual results -- but, according to you, we can't accept those because their predictions agree with qm and experiments.

By the way, thanks for the reference. My 'assertion' wrt a simplified 'realistic' view of the underlying optical disturbances is probably much too simplistic. It does seem to work for entangled photons produced by atomic cascades though. I'm just beginning a study of OPDC. So, my little simplification might turn out to be ridiculous.

Here's another paper (you've probably read it) that some viewers might be interested in. There's lots of good stuff at Sergienko's group's website.

http://people.bu.edu/alexserg/PRL3893_1993.pdf
Einstein-Podolsky-Rosen-Bohm Experiment Using Pairs of Light Quanta Produced by Type-II Parametric Down-Conversion
Authors:T.E. Kiess, Y.H. Shih, A.V. Sergienko, and C.O. Alley
Phys. Rev. Lett. v.71, pp. 3893-3897 (1993)

So far I don't find anybody saying that the correlations are due to action at a distance or ftl. Eg., in the paper referenced below, they define nonlocality rather innocuously (and in fact state that action at a distance isn't indicated). I think this might be the way that lots (most?) physicists think about it. Quantum nonlocality doesn't mean nonlocality. (The first link might time out, so I included a link to the preprint version.)

http://qopt.postech.ac.kr/publications/PhysRevA-60-p2685.pdf
http://arxiv.org/PS_cache/quant-ph/pdf/9811/9811060v1.pdf
Experimental study of a photon as a subsystem of an entangled two-photon state
Authors: Dmitry V. Strekalov, Yoon-Ho Kim, Yanhua Shih
Phys. Rev. A v.60, pp. 2685-2688 (1999)

The fact is that entangled particles have attributes that do not follow a local realistic explanation.

Only wrt Bell's LR model. Which we know doesn't fit the requirements of the experimental situation.

Considering the small experimental differences necessary for entanglement vs nonentanglement stats, and the fact that even LR models conforming to Bell's restrictions aren't that far away from qm predictions, and the fact that there are viable LR models that don't conform to Bell's restrictions, all support the idea that the 'problem of nonlocality' has to do with the way things are being talked about, and not anything to do with the existence of action at a distance or ftl anything.

Talk to Bell about this. Or God. I did not create our universe, so it is not my requirement. Next you will be complaining about the 4 color map theorem as being "inane".

The 4 color map theorem is logically rigorous. Bell's assessment of the form that an LR model of entanglement must take isn't.

Anyway, the requirement than any LR model in any form be incorrect is your requirement. You've been shown LR models whose predictions agree with those of qm and experimental results -- and your response is that you want them to produce a dataset that disagrees with qm and experimental results.

I know how you got there (there's only one way -- Bell's way), but wouldn't it make sense to at least look at them and evaluate whether they're realistic and/or local instead of dismissing them because they're quantitatively correct?

I'm going to keep my Bell talk to a minimum for the time being. You've opened up a whole new world for me with the OPDC stuff, and I feel compelled to learn as much about it as I can. (Hmmmm, maybe there is a method to your madness.) Anyway, thanks again.

 

[ThomasT]

If you are going to make statements like this, you had better back it up.

So perhaps you can give me an example if how a) EPR elements of reality are too restrictive; b) a classical case in which Bell's (2) is violated when considering the full universe.

In other words, what is wrong with Bell's definitions (other that you don't like the conclusions they inevitably lead to) ?

Wrt a), they're in the literature, and they encode the more reasonable interpretation of EPR's conception of reality that would allow joint detection to be represented in a nonseparable form. Wrt b), I don't understand what you're asking.

Bell represented locality via the factorability (separability) of the joint situation which is entailed by the requirement to represent joint detection in terms of individual detections. However, because this isn't the reality of the joint situation, then the locality condition's relevance to locality is screened out or superceded by the fact that the joint situation is being modeled in terms of individual parameters which simply can't be combined in the way that Bell requires them to be combined (and also correctly model the nonseparability of the experimental situation) in his LR model.

 

[my_wan]

This empirical fact may or may not have a realistic basis.

What do you mean by this? That the cos^2 theta rule can't be understood realistically?

No, that's not what I mean. But, at the end of the day, pragmatism trumps preconceptions. The empirical is what you take to the bank. We don't get to decide what nature is and isn't. I have an extensive list of classical analogs of QM, but in the general case it still breaks, and why it always breaks is tied with the issues in BI violations in some ways. So just because I agree with you, in principle, that there may be realistic mechanisms by some definition, I can't claim it must be so just because I can justify it in principle. It's just as unreasonable to marginalize people for trying, as it is unreasonable to claim what is true based solely on what can be heuristically justified.

%%%%%%%%%%

I reject the idea that a realistic theory is possible. It is really that simple. My definition of reality being the same as the EPR definition: if it can be predicted in advance, there must be an element of reality. But there cannot be 3 simultaneously real.

Here's a simplistic fundamental issue I have with that: Given an initial condition and momentums of a set of pool balls, I can predict in advance the topology of those balls will form an X. Does that make the X an 'element of reality' of those balls? If a measuring instrument simply selects a range of topologies, consistent with some condition, what does that leave you with wrt realism in EPR. I'll make this even clearer wrt Mermin's work you mention below.

This is not a requirement of QM, and in no way is QM given a preferred status in Bell other than by way of comparison.

Which was exactly my point. Bell counterfactually imposed a condition on QM that QM doesn't allow.

You cannot get a realistic theory with ANY function where there is rotational invariance, as Mermin demonstrated. Hess has provided nothing for me to reject other than his conclusion. There is no realistic model. Again.

Thanks for reminding me of this! In fact this is a fully general feature of all vectors, including vectorial components of classical objects!

Consider a pair of unit vectors, P and Q. You can even view them as a pair of balls colliding in space.
R_x = P_xQ_x
R_y = P_yQ_y
R_z = P_zQ_z

Now we consider the perpendicular case:
R_x = 0
R_y = 0
R_z = 0

But, if we rotate this coordinate system 45 degrees we get:
R_x = 1/2
R_y = -1/2
R_z = 0

But nature doesn't care how we labeled our coordinate system, or that these labels give us incongruent results wrt values. The fact remains that 'reality' is the same (even the same instance of reality) no matter how we choose our coordinate basis. If we claim unreality on the grounds that 1/2 = -1/2 = 0 is false, that's our problem, not one of reality. The arbitrary angle verses relative offset requirement in BI imposes this absolutely general mathematically incongruent wrt values of ALL vectors, not just polarizer settings in EPR experiments, but ANY classical vector.

Based on this, following the BI version of realism, it's trivially provable that, since vectorial components of pool balls is a measurable property, pool balls are not real.

QM does not ask for counterfactuality, so your argument is backwards. It is realism that requires extra assumptions, not QM.

Again
That was exactly my point. It was imposed on QM, not asked for by QM. In fact I went farther and said it's invalid under QM alone, just as it's invalid as settings for 3 unfair coins. It remains confusing how my point is continually objected to by making my point.

So if you think these requirements are absurd, well, that would simply mean you reject realism. Sorry, but you cannot have your cake and eat it too.

So if realism requires this extra assumption, this means that, since the vectorial components of pool ball collisions are measurable, yet incongruent wrt values, pool balls can't be real.

So define realism however you like. Define it like Hess if that makes you happy (or whatever his latest absurd definition of the week happens to be). But I won't agree that day is night, that blue is red, or whatever. I will stick with Einstein's elements of reality.

I don't agree that 1/2 = -1/2 = 0 either, but if that means I'm supposed to define the pool balls as not real on these grounds, I'll pass.

 

[billschnieder]

That may be the strongest objection yet. Like trying to define 3 coins that can all land on opposite sides, because couterfactually any 2 can.

You may be interested in this post from a previous thread that discusses the issue raised by Hess, clearly showing that correct labelling of variables is paramount to understanding violations of BIs.
https://www.physicsforums.com/showpost.php?p=2707087&postcount=69"

Consider a certain disease that strikes persons in different ways depending on circumstances. Assume that we deal with sets of patients born in Africa, Asia and Europe (denoted a,b,c). Assume further that doctors in three cities Lyon, Paris, and Lille (denoted 1,2,3) are are assembling information about the disease. The doctors perform their investigations on randomly chosen but identical days (n) for all three where n = 1,2,3,...,N for a total of N days. The patients are denoted Alo(n) where l is the city, o is the birthplace and n is the day. Each patient is then given a diagnosis of A = +1/-1 based on presence or absence of the disease. So if a patient from Europe examined in Lille on the 10th day of the study was negative, A3c(10) = -1.

According to the Bell-type Leggett-Garg inequality

Aa(.)Ab(.) + Aa(.)Ac(.) + Ab(.)Ac(.) >= -1

In the case under consideration, our doctors can combine their results as follows

A1a(n)A2b(n) + A1a(n)A3c(n) + A2b(n)A3c(n)

It can easily be verified that by combining any possible diagnosis results, the Legett-Garg inequalitiy will not be violated as the result of the above expression will always be >= -1, so long as the cyclicity (XY+XZ+YZ) is maintained. Therefore the average result will also satisfy that inequality and we can therefore drop the indices and write the inequality only based on place of origin as follows:

<AaAb> + <AaAc> + <AbAc> >= -1

Now consider a variation of the study in which only two doctors perform the investigation. The doctor in Lille examines only patients of type (a) and (b) and the doctor in Lyon examines only patients of type (b) and (c). Note that patients of type (b) are examined twice as much. The doctors not knowing, or having any reason to suspect that the date or location of examinations has any influence decide to designate their patients only based on place of origin.

After numerous examinations they combine their results and find that

<AaAb> + <AaAc> + <AbAc> = -3

They also find that the single outcomes Aa, Ab, Ac, appear randomly distributed around +1/-1 and they are completely baffled. How can single outcomes be completely random while the products are not random. After lengthy discussions they conclude that there must be superluminal influence between the two cities.

But there are other more reasonable reasons. Note that by measuring in only two citites they have removed the cyclicity intended in the original inequality. It can easily be verified that the following scenario will result in what they observed:

- on even dates Aa = +1 and Ac = -1 in both cities while Ab = +1 in Lille and Ab = -1 in Lyon
- on odd days all signs are reversed

In the above case
<A1aA2b> + <A1aA2c> + <A1bA2c> >= -3
which is consistent with what they saw. Note that this equation does NOT maintain the cyclicity (XY+XZ+YZ) of the original inequality for the situation in which only two cities are considered and one group of patients is measured more than once. But by droping the indices for the cities, it gives the false impression that the cyclicity is maintained.

The reason for the discrepancy is that the data is not indexed properly in order to provide a data structure that is consistent with the inequalities as derived.Specifically, the inequalities require cyclicity in the data and since experimenters can not possibly know all the factors in play in order to know how to index the data to preserve the cyclicity, it is unreasonable to expect their data to match the inequalities.

For a fuller treatment of this example, see Hess et al, Possible experience: From Boole to Bell. EPL. 87, No 6, 60007(1-6) (2009)

Note that in deriving Bell's inequalities, Bell used Aa(l), Ab(l) Ac(l), where the hidden variables (l) are the same for all three angles. For this to correspond to the Aspect-type experimental situation, the hidden variables must be exactly the same for all the angles, which is an unreasonable assumption because each particle could have it's own hidden variables with the measurement equipment each having their own hidden variables, and the time of measurement after emission itself a hidden variable. So it is more likely than not that the hidden variables will be different for each measurement. However, in actual experiments the photons are only measured in pairs (a,b), (a,c) and (b,c). The experimenters, not knowing the exact nature of the hidden variables, can not possibly collect the data in a way that ensures the cyclicity is preserved. Therefore, it is not possible to perform an experiment that can be compared with Bell's inequalities.

 

[DrChinese]

Wrt a), they're in the literature, and they encode the more reasonable interpretation of EPR's conception of reality that would allow joint detection to be represented in a nonseparable form. Wrt b), I don't understand what you're asking.

I am asking for a reference for these alternative reasonable definitions. I am not familiar with any others generally out there. I have yet to see actual proposed ones.

As to b): if you think there is a classical counterexample, give it! And please, nothing where we have an unfair sample of doctors or similar. A full universe. You won't be able to do it!

 

[DrChinese]

Which was exactly my point. Bell counterfactually imposed a condition on QM that QM doesn't allow.

You still have it backwards. QM has nothing to do with it. And I don't follow your pool ball example.

 

[DrChinese]

You may be interested in this post from a previous thread that discusses the issue raised by Hess, clearly showing that correct labelling of variables is paramount to understanding violations of BIs.
https://www.physicsforums.com/showpost.php?p=2707087&postcount=69"

Again, this example is an attempt to show that there is an unfair sample of a full universe. This is not Bell at all. For Bell, you use a full universe of trials.

 

[ThomasT]

I am asking for a reference for these alternative reasonable definitions. I am not familiar with any others generally out there. I have yet to see actual proposed ones.

As to b): if you think there is a classical counterexample, give it! And please, nothing where we have an unfair sample of doctors or similar. A full universe. You won't be able to do it!

The few that I know of aren't published. Just in preprint. You're probably aware of most, if not all, of them. Since it's unlikely that any of it will get published, there's not much to discuss.

By the way, after thinking about it, I think you're right about Bell's (2) wrt EPR settings. There's nothing special about these settings except that a certain LR implementation of Bell's (2) does agree with qm for EPR settings (and |a-b|=45^o). But other than that no. And after looking at Bell's paper more closely it does seem that he's showing that an LR implementation of (2) is incompatible with all qm predictions for any settings.

 

[my_wan]

You still have it backwards. QM has nothing to do with it. And I don't follow your pool ball example.

But QM does have something to do with it. QM says the counterfactual case is interfered with by some some mechansim, often presumed FTL. Perhaps it's really interefereing with the absurdity the pre-conditions placed on the HV's from the start.

When you say you don't follow my pool ball example, what don't you get? Can you look at any single vectorial outcome of a classical interaction, and ask what that vectorial product looks like under different coordinate rotations? The 'values' of the 'predicted' measurables are incompatible wrt those 'values' obtained under an arbitrary coordinate rotation. Per the realism definition the predictability of those values, given any particular rotation, requires us to defines those vectorial products as 'elements of reality'. But rotate your coordinate system on this same physical event and your value obtained from this 'element of reality' becomes inconsistent with the prior 'value' of the same event.

 

[DevilsAvocado]

And please, nothing where we have an unfair sample of doctors or similar.

 

[ThomasT]

No, that's not what I mean. But, at the end of the day, pragmatism trumps preconceptions. The empirical is what you take to the bank. We don't get to decide what nature is and isn't. I have an extensive list of classical analogs of QM, but in the general case it still breaks, and why it always breaks is tied with the issues in BI violations in some ways. So just because I agree with you, in principle, that there may be realistic mechanisms by some definition, I can't claim it must be so just because I can justify it in principle. It's just as unreasonable to marginalize people for trying, as it is unreasonable to claim what is true based solely on what can be heuristically justified.

Thanks for the reply. Some interesting considerations for future threads.

 

[my_wan]

Again, this example is an attempt to show that there is an unfair sample of a full universe. This is not Bell at all. For Bell, you use a full universe of trials.

No, only that's it's, in principle, possible that the sampling used by Bell isn't valid. It has nothing to do with the full universe's sampling, and everything to do with how we choose to define our sampling of it.

Wrt the vector argument, there's a very simple reason vectors are not generally rotation invariant. When looking at the product of a pair of vectors, the defining vectors are indeterminate. That is there is an arbitrarily large possible number of vector pairs that could have created that vector. That 1 vector can even represent the result of an arbitrarily large number of products from actual vectors.

So when Bell's inequalities specifies any arbitrary theta must be modeled to avoid FTL, it could be requiring the particular vectorial instances that defined a vector to be uniquely identified after the fact. This is impossible even for the product of a single pair of vectors, given only a single resulting vector.

---------
I hoped a more reasonable objection would be posed. Like the fact that the pool ball example doesn't define a rotationally invariant function, like Mermin defined. Whereas QM is dependent on the existence rotationally invariant functions. So how can a rotationally invariant functions represent anything real, if the pool ball analogy holds?

Consider a particle with a real default polarization. The default polarization is -only- unique in that a polarizer at that setting has essentially a 100% chance of passing that particle, but offsets can also pass some of the time via cos^2(theta). If the default polarization is completely randomized over a large group of particles, it's physically impossible for anyone polarizer setting to uniquely define a statistical function unique to a given polarizer setting. Only the particular sequence of detections can be unique, case instances of a probability which, by definition, are not themselves probabilities, which are later used to define the coincidences. Thus probability functions, not the case instances that result from them, are physically -required- to be rotationally invariant.

This would explain also why I could only model inequality violations, in my computer simulations, if I restricted one or the other setting to be defined at 0 angle. Even though the 0 angle could be arbitrarily chosen, and this didn't uniquely identify the other detector setting in calculating the detection sequence for later comparison to derive coincidences. Perhaps I should attempt to replace my binary bits with some form of predefined sets of vectors.

 

[billschnieder]

Again, this example is an attempt to show that there is an unfair sample of a full universe. This is not Bell at all. For Bell, you use a full universe of trials.

I suspect you have ready to produce a citation to a published example of an experiment in which they made absolutely sure that the full universe of all possible values of all hidden variables was realized.

In any case, the point of the example is that by making similar errors in macroscopic situations, you can create FTL paradoxes at the macroscopic level too.

As my_wan already explained, the error is NOT the fact that the data is incomplete or sampled unfairly. The error is the fact that the data is not properly indexed according to the contexts. In other words, multiple contexts are mixed together in a manner not expected by the inequalities, such that the only cases for which the inequalities will be universally valid irrespective of how the data is indexed, are non-contextual variables.

 

[DrChinese]

I suspect you have ready to produce a citation to a published example of an experiment in which they made absolutely sure that the full universe of all possible values of all hidden variables was realized...

I think you are admitting that Bell is correct. There is no local realistic universe.

And we have already been through the bit about the fair sampling. There are a number of experiments that do not require the fair sampling assumption that I have already referenced. You reject all counterevidence so it is meaningless to discuss this with you.

I suspect you even like the Monkees more than the Beatles.

 

[DrChinese]

So when Bell's inequalities specifies any arbitrary theta must be modeled to avoid FTL, it could be requiring the particular vectorial instances that defined a vector to be uniquely identified after the fact. This is impossible even for the product of a single pair of vectors, given only a single resulting vector.

...

This would explain also why I could only model inequality violations, in my computer simulations, if I restricted one or the other setting to be defined at 0 angle. Even though the 0 angle could be arbitrarily chosen, and this didn't uniquely identify the other detector setting in calculating the detection sequence for later comparison to derive coincidences. Perhaps I should attempt to replace my binary bits with some form of predefined sets of vectors.

All it takes is one.

 

[my_wan]

All it takes is one.

What conditions must be met to qualify as this "one"? Does it require an explicit theory that explains exactly the mechanism by which BI violations occur? Does is simply require a toy models which mimics such violations? Are these (toy) models required to be rotational invariant, in spite of the fact that you pointed out Mermin showed rotational invariance entail non-real variables? Are you denying that realistic classical variables exist that lack rotational invariance?

Why do I ask so many questions at once? Because I give detailed explanations and spread dozens of questions and you never answer anyway, so I ask in irony. You responses, or lack of, are tipping my scales.

Look at how you just now responded to the -RAW- sarcasm of billschnieder, by accusing him of an admission of your point of view.

I think you are admitting that Bell is correct. There is no local realistic universe.

And we have already been through the bit about the fair sampling. There are a number of experiments that do not require the fair sampling assumption that I have already referenced. You reject all counter evidence so it is meaningless to discuss this with you.

I suspect you even like the Monkees more than the Beatles.

The "fair sampling" accusation here is facetious as hell., and you know it. You've taken a prior issue, where the sampling accuracy of the experimental data was questioned, and pretending it's the same argument contained in a toy model describing contextually of variables. I think you know good and well that "fair sampling" is a separate issue, and if I'm wrong, why respond to explanations that its not with accusations of your opponents admitting they are wrong in the same post they are explaining this to you?

You've continually mirrored my points, as if they were a denial of my points. You've claimed ignorance repeatedly, even of something so simple as a vectorial product before and after a coordinate rotation. Failed to explain your position when asked. Failed to even explain what you claimed not to understand, even when asked. Continually, and chronically, fail to provide any context, or justification, or explanation, to your rebuttals. You even fail to specify what, in post for which much effort was put in, your rebuttals actually refer to in that post.

What's your point of even debating here? To run authoritative interference of any viewpoints you don't like?

Show me I'm wrong, and answer some questions. Ask some questions if somethings not clear. But to simply keep accusing people of viewpoints they are expending great effort and honest feedback to deny, with no good faith return rebuttals, appears awfully bad to me. My apologies for the aggravation, but it appears well called for when I'm not the only one getting this treatment, and others seem to understand what you deny understanding of. Without even the courtesy of questions indicate where the clarity was lacking, only accusations of admissions to your point of view.

The real shame is that you have a perspective I really really want to understand.

 

[DevilsAvocado]

Changes in the set up are all that you need to change the distribution of outcomes -- you don't need any 'thing' other than equipment characteristics, i.e., no reference to quantum entities, waves, etc. For example, see section 4.3 Geometrical Account of QLE starting on p 28 of our FoP paper, http://users.etown.edu/s/stuckeym/FOP 2008.pdf. In particular notice how how Eq. 31 becomes Eq. 32 on p. 29.

Thanks RUTA, for the interesting paper.

"[URL Spacetime and the Quantum:
Relational Blockworld and the Quantum Liar Paradox[/B][/URL]

W.M. Stuckey • Michael Silberstein • Michael Cifone

...
It is now generally believed that Einstein-Podolsky-Rosen (EPR) correlations, i.e., correlated space-like separated experimental outcomes which violate Bell’s inequality, force us to abandon either the separability or locality principle.
...
As we will show, the Relational Blockworld [9–11] interpretation of NRQM points to a far more intimate and unifying connection between spacetime and the quantum than most have appreciated.
...
RBW employs the spatiotemporal relations via symmetries of the entire (past, present and future) experimental configuration and is thus fundamentally kinematical. And unlike other BW inspired accounts of quantum mechanics such as BCQM, RBW is truly acausal, adynamical and atemporal.

I guess that in this field of view you are right – there is nothing 'special' about the wires 'interacting' with the wave function in the Afshar experiment – it’s just a different setup that generates a different mathematical (RBW) formula to explain what happens.

For a layman like me it’s quite easy, if one has to make a choice of, what can be consider more real than the other – and I intuitively choose the experiment and the physical wires, not the RBW mathematics, as my reality. Maybe future progress in science can physically prove me wrong – and then I have to change my mind, whether I like it or not.

Another 'objection' I have against RBW is the way you get rid of 'one problem' (separability vs. locality principle) by introducing another (to me stranger) 'phenomena' in; symmetries of the entire past, present and future + truly acausal, adynamical and atemporal...?

It doesn’t give me that 'natural' "WOW-feeling"... but maybe it’s idiocy to look/hope for some "human/natural/logical" explanation to what’s going on in the QM-world... ??

 

[DrChinese]

What conditions must be met to qualify as this "one"? Does it require an explicit theory that explains exactly the mechanism by which BI violations occur? Does is simply require a toy models which mimics such violations? Are these (toy) models required to be rotational invariant, in spite of the fact that you pointed out Mermin showed rotational invariance entail non-real variables? Are you denying that realistic classical variables exist that lack rotational invariance?

Why do I ask so many questions at once? Because I give detailed explanations and spread dozens of questions and you never answer anyway, so I ask in irony. You responses, or lack of, are tipping my scales.

Look at how you just now responded to the -RAW- sarcasm of billschnieder, by accusing him of an admission of your point of view.



The "fair sampling" accusation here is facetious as hell., and you know it. You've taken a prior issue, where the sampling accuracy of the experimental data was questioned, and pretending it's the same argument contained in a toy model describing contextually of variables. I think you know good and well that "fair sampling" is a separate issue, and if I'm wrong, why respond to explanations that its not with accusations of your opponents admitting they are wrong in the same post they are explaining this to you?

You've continually mirrored my points, as if they were a denial of my points. You've claimed ignorance repeatedly, even of something so simple as a vectorial product before and after a coordinate rotation. Failed to explain your position when asked. Failed to even explain what you claimed not to understand, even when asked. Continually, and chronically, fail to provide any context, or justification, or explanation, to your rebuttals. You even fail to specify what, in post for which much effort was put in, your rebuttals actually refer to in that post.

What's your point of even debating here? To run authoritative interference of any viewpoints you don't like?

Show me I'm wrong, and answer some questions. Ask some questions if somethings not clear. But to simply keep accusing people of viewpoints they are expending great effort and honest feedback to deny, with no good faith return rebuttals, appears awfully bad to me. My apologies for the aggravation, but it appears well called for when I'm not the only one getting this treatment, and others seem to understand what you deny understanding of. Without even the courtesy of questions indicate where the clarity was lacking, only accusations of admissions to your point of view.

The real shame is that you have a perspective I really really want to understand.

I have repeated indicated that it is not possible to come up with a local realistic dataset. That is all it takes to refute Bell. You tried and failed, as have others - including myself! Yes, I have tried to break Bell many times and this has taught me where its strengths are.

I am trying to be patient, but what I actually have on my hands is people who deny a standard scientific viewpoint which has been scrutinized by thousands. Which has over a thousand papers published annual with both theoretical and experimental support. And you are treating my position - the standard one - as if it requires non-stop defense. Well, actually the burden is on you.

Yes, I know that science can be wrong but that possibility does not make it wrong and is in NO WAY a help to your position. It should give you pause, however, in your assertions. I know that whenever I find myself speculating against the mainstream, that is usually a sure sign that I need to do some additional research. I do actively disagree with some scientific research - especially in the area of human research studies - but I temper that with the desire to present something USEFUL in its place. I have repeatedly suggested that

It does little good for you to say "I reject standard definitions" and "I need more proof". I can't provide that for you, and in fact no one can. Only you can do that.

-----------------------------

If you think that Bell is wrong, consider one of the following:

a) Come up with a dataset. You should have already learned the difficulty with this after developing your model.
b) Come up with a different and better definition of locality that yields the possibility of a local realistic dataset (under this revised definition). Then present it and see if others accept this as an alternative definition.
c) Come up with a different and better definition of realism that yields the possibility of a local realistic dataset (under this revised definition). Then present it and see if others accept this as an alternative definition.

As to the fair sampling assumption: billschnieder brought it up again, not me. It does not properly belong in discussions of EPR and Bell, instead is more appropriate to the evaluation of Bell tests. I take this area quite seriously and am involved in active research into such models, specifically looking at the De Raedt local realistic models. But please note: they are the ONLY team that has EVER - to my knowledge - provided a local realistic dataset to critique. So you are far off the mark, my friend. Give me something specific that addresses the meat of the subject.

Stuff like your billiard ball example - and billschnieder's African doctors - does not come close. This is the quantum world, and experimentalists are running hundreds of experiments that are flat out in contradiction to the local realistic world.

 

[my_wan]

I have repeated indicated that it is not possible to come up with a local realistic dataset. That is all it takes to refute Bell. You tried and failed, as have others - including myself! Yes, I have tried to break Bell many times and this has taught me where its strengths are.

The only failure I had was rotational invariance in the underlying mechanism, which did not destroy rotational invariance in the sense that it made no difference how the coordinate system was rotated. Thus in spite of lacking rotational invariance, like ALL classical mechanisms, it was in fact coordinate independent. This is nothing new in the literature. Consider:
http://arxiv.org/abs/quant-ph/0407232"
Phys. Rev. Lett. 93, 230403 (2004)

http://arxiv.org/abs/quant-ph/0407232]Rotational[/PLAIN] invariance of physical laws is a generally accepted principle. We show that it leads to an additional external constraint on local realistic models of physical phenomena involving measurements of multiparticle spin 1/2 correlations. This new constraint rules out such models even in some situations in which standard Bell inequalities allow for explicit construction of such models. The whole analysis is performed without any additional assumptions on the form of local realistic models.

Are you denying that such models exist? You have pointed out that Mermin showed rotational invariance cannot be mimicked by any realistic mechanism. I showed why not even the vectorial product of a pool ball collision is rotational invariant, though you deemed it incomprehensible. So any such underlying realistic mechanism can't be rotational invariant.

Yet it's trivial to show that any probability function written for a randomized rotation of a mechanism lacking rotational invariance will itself be rotational invariant. Do you deny this?

If you cannot deny both of the red questions, then the only way to deny the possibility of realistic models is to invoke rotational invariance is to invoke it as -fundamental-, rather than a probabilistic result of a mechanism lacking rotational invariance. But that only invokes the completeness claim of QM that Einstein denied, in order to deny the incompleteness LHV's depend on to attempt such models to begin with! It's having your cake and eating it to.

Yes, I want a very specific answer to BOTH of those questions. What opinion you indicate based on authority means nothing.

Here are the questions again for which even a yes/no answer would be a breakthrough:
1) Do coordinate independent LHV models of BI violations exist that lack rotational invariance?
2) Does a rotational invariant probability function exist for any mechanism with a randomized rotation?

Answers are non-negotiable.

 

[ThomasT]

... snip long tirade re DrC ...

The real shame is that you have a perspective I really really want to understand.

I agree with much of what you said in your tirade re DrC. But since I have learned much from him (as well as you and others) I have wanted to give him the benefit of the doubt and simply assume that he had a deeper understanding of Bell's theorem -- and then proceed to present my current lines of thought via my still developing comprehension of the subject in a sort of authoritative style. Despite the fact that my thinking has been wrong wrt certain details, or maybe because of it, I've learned from these recent Bell threads.

Wrt DrC's perspective on Bell, it seems pretty clear to me that he thinks that Bell's LR construction is unassailable and physically significant -- so that even if Bell locality doesn't represent locality, that, nevertheless, Bell's modelling of the experimental situation does indeed represent the reality of the experimental situation -- and hence nature is either nonlocal or, well, I'm not sure what the alternative (wrt reality) is. The possibility that Bell's ansatz might not actually be representing the reality of the situation, and therefore be physically insignificant, simply isn't considered. *

So, vetting your ideas to someone of that persuasion is something of a nonstarter. Of course, the difficulty of the task for those who think there might be something about Bell's treatment, and certain interpretations thereof, that isn't quite right is compounded by the apparent fact that DrC's view is the mainstream view (at least wrt the set of physicists who have an opinion re Bell). So, there are few published articles (quite a few preprints, but they're off limits for discussion here) and very little discussion by professionals of the approaches they present.

Anyway, I think that I understand, superficially at least, and conceptually to a certain extent, what you're talking about -- and it's interesting.
-------------------------------------------
* (The upside to Bell's theorem, even if it's eventually generally interpreted to be physically insignificant, is that it will remain extremely significant because of what it's generated experimentally, theoretically, and philosophically.)

 

[my_wan]

ThomasT,
I to have benefited from DrC. I'm more than happy to have any notions I present here completely destroyed. That's the only reason I take one side of the debate, knowing that it's open to be destroyed.

My tripping point was not his denials, nor his opinions. My tripping point was consistent, chronic, failures to respond to any rebuttals, or even reference what specifically was the issue in his general denials.

 

[DrChinese]

The only failure I had was rotational invariance in the underlying mechanism, which did not destroy rotational invariance in the sense that it made no difference how the coordinate system was rotated. Thus in spite of lacking rotational invariance, like ALL classical mechanisms, it was in fact coordinate independent. This is nothing new in the literature. Consider:
http://arxiv.org/abs/quant-ph/0407232"
Phys. Rev. Lett. 93, 230403 (2004)



Are you denying that such models exist? You have pointed out that Mermin showed rotational invariance cannot be mimicked by any realistic mechanism. I showed why not even the vectorial product of a pool ball collision is rotational invariant, though you deemed it incomprehensible. So any such underlying realistic mechanism can't be rotational invariant.

Yet it's trivial to show that any probability function written for a randomized rotation of a mechanism lacking rotational invariance will itself be rotational invariant. Do you deny this?

If you cannot deny both of the red questions, then the only way to deny the possibility of realistic models is to invoke rotational invariance is to invoke it as -fundamental-, rather than a probabilistic result of a mechanism lacking rotational invariance. But that only invokes the completeness claim of QM that Einstein denied, in order to deny the incompleteness LHV's depend on to attempt such models to begin with! It's having your cake and eating it to.

Yes, I want a very specific answer to BOTH of those questions. What opinion you indicate based on authority means nothing.

Here are the questions again for which even a yes/no answer would be a breakthrough:
1) Do coordinate independent LHV models of BI violations exist that lack rotational invariance?
2) Does a rotational invariant probability function exist for any mechanism with a randomized rotation?

Answers are non-negotiable.

You make me laff. Non-negotiable?

Apparently you are not aware of PhysicsForums policy regarding personal theories. Generally, these are not allowed. That is why I repeatedly mention that what I am saying is standard, accepted physics. Not because it is a resort to authority. Not that authoritative sources are bad, they are the best. But as I said before, it only takes one.

So to answer some of your "questions": Yes, I deny that that rotational invariance cannot be modeled by any local realistic theory. But I do think it is a constraint. In fact, thatnks for the reference, not sure if I had seen that or not. Can such models be constructed or whatever it is you ask? I guess so, haven't thought much about it and don't plan to. The problems of constructing local realistic theories is not one of my priorities as I follow Bell. Apparently you have convinced yourself that local realistic theories cannot be constructed for other reasons. Ergo, you should likewise reject local realism as I do.

I am not otherwise sure why you are focusing on rotational invariance, in fact I am not even sure we are talking about the same thing. In my mind, rotational invariable is getting the same answer in any rotated reference frame. There can be no preferred frame. You model suffered from the problem that it appears to work as long as one of the angles is 0 - but not at other angle settings. Therefore it is not rotationally invariant. Is that a requirement of a model? I guess so, because no one has ever done an experiment demonstrating rotational variance. Therefore I would expect any rotational variant model - such as your simulation - to be falsifiable by experiment. A fair requirement, don't you think, that the model be held up to experimental examination? Or is that too much to ask?

 

[DrChinese]

(The upside to Bell's theorem, even if it's eventually generally interpreted to be physically insignificant, is that it will remain extremely significant because of what it's generated experimentally, theoretically, and philosophically.)

I think that is praise for Bell.

And yes, I think Bell's logic is unassailable but that certainly doesn't mean it is off limits.

 

[unusualname]

Don't want to appear insensitive, but shouldn't someone point out that arguing about the validity of Bell's Theorem experiments seems pretty redundant now, since multi-particle entanglement experiments have trivially demonstrated that local realism fails (and in particular that the EPR argument for it fails)

eg google Greenberger Horne Zellinger Going Beyond Bell's Theorem

 

[DrChinese]

Don't want to appear insensitive, but shouldn't someone point out that arguing about the validity of Bell's Theorem experiments seems pretty redundant now, since multi-particle entanglement experiments have trivially demonstrated that local realism fails (and in particular that the EPR argument for it fails)

eg google Greenberger Horne Zellinger


Going Beyond Bell's Theorem

This is a great point!

In addition to the amazing GHZ, there are also: Hardy's Paradox, Leggett's Theorem, and works by Cabello including ones following Kocken-Specker. And others as well, generally casting strong doubt on ANY form of realism (although for technical reasons, the Bohmians generally believe that non-local realism is not ruled out by these).

[Bill Murray]I'm really close on this one...[/Bill Murray]

 

[my_wan]

You make me laff. Non-negotiable?

Apparently you are not aware of PhysicsForums policy regarding personal theories. Generally, these are not allowed. That is why I repeatedly mention that what I am saying is standard, accepted physics. Not because it is a resort to authority. Not that authoritative sources are bad, they are the best. But as I said before, it only takes one.

I have dropped many lines of reasoning to maintain distance from personal theories, and you know it. Neither can you claim that HV models are lacking in the published literature. So you can only claim what you take to be the predominate view toward what is published. Yet few I have spoken to take as absolute a few as what you have expressed. Of course I haven't hired Gallup to give me any numbers on that.

So to answer some of your "questions": Yes, I deny that that rotational invariance cannot be modeled by any local realistic theory.

This was not an answer to any question I asked, in any post. It sounds more like you looked at the consequences of actually answering the questions, and chose a preemptive response to those consequences.

But I do think it is a constraint. In fact, thatnks for the reference, not sure if I had seen that or not. Can such models be constructed or whatever it is you ask? I guess so, haven't thought much about it and don't plan to. The problems of constructing local realistic theories is not one of my priorities as I follow Bell.

Hmm, that makes your response here suspect:

You tried and failed, as have others - including myself!

Apparently you have convinced yourself that local realistic theories cannot be constructed for other reasons. Ergo, you should likewise reject local realism as I do.

There you go again. Avoided the questions, and added woefully ridiculous characterizations of other peoples post to claim consistency with you pov.

I am not otherwise sure why you are focusing on rotational invariance, in fact I am not even sure we are talking about the same thing. In my mind, rotational invariable is getting the same answer in any rotated reference frame. There can be no preferred frame.

You brought it up, and I thanked you for reminding me. Yes but frame independence is not the same thing as value independence. If you call the pockets on a pool table detectors, then measured outcomes of the exact same physical set of events on the table will be very dependent on the orientation of the table relative to the events on it. Given the trajectory of a pool ball alone, you can't even determine after the fact what angle the q-ball hit it.

You model suffered from the problem that it appears to work as long as one of the angles is 0 - but not at other angle settings. Therefore it is not rotationally invariant.

Woefully misleading mischaracterization. In fact the 0 angle of the detector can be anywhere, and you can change the 0 angle to any other 0 angle you wish, anytime. You can also move it to the other detector instead. Because rotating the coordinate system is not a physical thing, because coordinate systems are not a physical thing.

The photons are written as numbers in a text file. So you can create new randomized photons anytime, or use the exact same ones in the same order with 0 angle defined anywhere entirely differently from the last run of the same set of photon numbers, and still get the same BI violations. You can even account for this rotating coordinate system by making sure the photon definition of default orientation is not rotated when you rotate the coordinate system and still get BI violations.

Your characterization is flat out false. It needs a 0 definition for the same reason the self velocity of an inertial observer either needs a 0 self definition or FTL signal to account for a non-zero self velocity definition. Else no 2 observers could ever agree on what the momentum should be under arbitrarily defined self velocities.

Is that a requirement of a model? I guess so, because no one has ever done an experiment demonstrating rotational variance. Therefore I would expect any rotational variant model - such as your simulation - to be falsifiable by experiment. A fair requirement, don't you think, that the model be held up to experimental examination? Or is that too much to ask?

My model didn't rotationally vary even when the rotation was varied, only the definitions of the frame of reference was changed to match the various settings. In other words you could also rotate all the default orientations of the individual photons and still get BI violations also. Rotating a coordinate system is non-physical, and either detector can have any -absolute- orientation variations wrt each other in space you want. Do you get it?

But, you still didn't answer my questions. Why is that? Do you wish another try at answering those questions, or is that too tough? You challenged me on negative probabilities before I even found your page on them. I not only demonstrated, by academic definition, that your negative probabilities were not probabilities but case instances, I also demonstrated and identified exactly which case instances they were. Irrespective of any interpretation. Though I provided a possible interpretation also. I now challenge you to a far more basic request: Answer questions!

 

[my_wan]

Don't want to appear insensitive, but shouldn't someone point out that arguing about the validity of Bell's Theorem experiments seems pretty redundant now, since multi-particle entanglement experiments have trivially demonstrated that local realism fails (and in particular that the EPR argument for it fails)

eg google Greenberger Horne Zellinger


Going Beyond Bell's Theorem

Nobody is arguing the empirical validity of any experiment, or the reality of BI violations in general. Only what is and isn't physically required to model them.

 

[unusualname]

Nobody is arguing the empirical validity of any experiment, or the reality of BI violations in general. Only what is and isn't physically required to model them.

But why?

 

[my_wan]

But why?

Certainly not because the inequality is wrong, but because it's physical meaning may be taken with a far higher level of generality than what the empirical fact of it justifies.

 

[unusualname]

Certainly not because the inequality is wrong, but because it's physical meaning may be taken with a far higher level of generality than what the empirical fact of it justifies.

Maybe, but don't you agree that the subtlety of the arguments are more in the philosophically delicate vein than scientifically interesting? The resolution to your logical conundrums can't be scientifically useful since as you probably know, EPR type arguments have been refuted now using trivial 100% correlation results (see links above) rather than statistical ones.

If you find some doubt in the reasoning attached to the implications of results of Bell experiments, it's a bit like discovering there are logical issues in Newton's Principia.

Your ideas do seem deeply thought out and might make an interesting paper from a historical/philosopical perspective.

And after all the thread title does ask a specific question

 

[DrChinese]

a. Neither can you claim that HV models are lacking in the published literature.

b. Here are the questions again for which even a yes/no answer would be a breakthrough:
1) Do coordinate independent LHV models of BI violations exist that lack rotational invariance?
2) Does a rotational invariant probability function exist for any mechanism with a randomized rotation?

a. The only suitably realistic one is the De Raedt et al model. And by suitably I mean able to generate simultaneous values for a, b, c. (Keep in mind that it exploits the Fair Sampling assumption, which is generally not used by other groups.) ALL of the others are not realistic, i.e. they cannot generate a local realistic dataset. Examples of published failures would be Hess, Phillipp, Santos, Christian, Laudisa, Broda, Matzkin, Thompson etc. If they could provide a dataset, my assumption is that they would - which makes them failures. Many have also be attacked on other grounds (Santos, Hess, Phillipp possibly gaining some kind of records in that regard). De Raedt's, on the other hand, provides an event by event dataset, which I have personally verified. I would be glad to look at anything any of these other authors presents in the way of a realistic dataset. In fact, you can consider it an open challenge.

So there are none such remaining in the literature as far as I am aware. That is my claim.


b. As to your "questions": Sure, let's see if I can be clearer (although these questions are really weird to me):
1. No, because there are NO LHVs that violate Bell inequalities. See Bell.
2. I believe a linear one might work. But I am not an expert in this.

P.S. Your comment about my having tried to find loopholes in Bell ("suspect") is off the mark. It is no different that ways I may have tried to find loopholes in the HUP. Or in other aspects of QM or GR. Just because I follow them does not mean I don't try to push the envelope. No telling what I might learn from trying.

 

[DrChinese]

Certainly not because the inequality is wrong, but because it's physical meaning may be taken with a far higher level of generality than what the empirical fact of it justifies.

"No physical theory of local Hidden Variables can ever reproduce all of the predictions of Quantum Mechanics."

You think that is shows a physical meaning which is more general than justified empirically?

I don't see this as something which is empirical. Nor do I see it as more general than warranted. Nor am I aware of any physical theory which threatens this conclusion.

 

[my_wan]

"No physical theory of local Hidden Variables can ever reproduce all of the predictions of Quantum Mechanics."

You think that is shows a physical meaning which is more general than justified empirically?

I don't see this as something which is empirical. Nor do I see it as more general than warranted. Nor am I aware of any physical theory which threatens this conclusion.

Again you have placed a backward interpretation of my words.
1) Yes. BI violations are an empirical fact. That is ALL that empirical means in this case.
2) No, I didn't imply "empirical" meant physical in any way. It's merely a fact that BI violations are an empirical fact.

I don't see this as something which is empirical.

Do you even know what "empirical" means? It means it is an observable fact, independent of any interpretation placed on it.

Nor do I see it as more general than warranted.

Presumably your associating "more general" with the empirical fact itself. An empirical fact is only a repeatable observation. The generality of it applies only to the interpretation, not the empirical fact.

Nor am I aware of any physical theory which threatens this conclusion.

I'm not aware of any physical theory which threatens the color orange either. I didn't know it was possible to butcher a parsing of my sentences so badly. Is my English really that bad?

I give up...