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minkwe wrote:Fred, actually you can test and confirm EPR realism by performing a single run of the EPRB experiment with identical settings at Alice and Bob. If you obtain perfect correlation after accounting for noise, then you have realism. Inequalities are simply paradox factories.

FrediFizzx wrote:

minkwe wrote:Fred, actually you can test and confirm EPR realism by performing a single run of the EPRB experiment with identical settings at Alice and Bob. If you obtain perfect correlation after accounting for noise, then you have realism. Inequalities are simply paradox factories.

Ah yes, that is true. So all a hidden variable theory needs to predict is correlation with a and b settings the same (a = b) to be considered realistic. That is pretty simple.

Or anti-correlation with a = -b. And it actually should probably predict both. Well... I guess it should also predict that the A and B outcomes will be 50-50 +1 or -1.
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thray wrote:

FrediFizzx wrote:

minkwe wrote:Fred, actually you can test and confirm EPR realism by performing a single run of the EPRB experiment with identical settings at Alice and Bob. If you obtain perfect correlation after accounting for noise, then you have realism. Inequalities are simply paradox factories.

Ah yes, that is true. So all a hidden variable theory needs to predict is correlation with a and b settings the same (a = b) to be considered realistic. That is pretty simple.

Or anti-correlation with a = -b. And it actually should probably predict both. Well... I guess it should also predict that the A and B outcomes will be 50-50 +1 or -1.
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Fred, what Bell loyalists will tell you, is that setting a = b, leaves out the freedom of the experimenter to choose and change detector settings. They don't recognize non-arbitrarily-chosen initial conditions. They really don't understand physical measure space -- they take it to be the quantum configuration space -- and since the conclusion of Bell's Theorem is that quantum configuration space cannot map onto physical space without a nonlocal model, non-locality is a prior assumption.

To prove it -- ask a Bell believer to define a measure space. Should be simple enough -- in what space are Bell-Aspect measures taken?

FrediFizzx wrote:

thray wrote:

FrediFizzx wrote:

minkwe wrote:Fred, actually you can test and confirm EPR realism by performing a single run of the EPRB experiment with identical settings at Alice and Bob. If you obtain perfect correlation after accounting for noise, then you have realism. Inequalities are simply paradox factories.

Ah yes, that is true. So all a hidden variable theory needs to predict is correlation with a and b settings the same (a = b) to be considered realistic. That is pretty simple.

Or anti-correlation with a = -b. And it actually should probably predict both. Well... I guess it should also predict that the A and B outcomes will be 50-50 +1 or -1.
.

Fred, what Bell loyalists will tell you, is that setting a = b, leaves out the freedom of the experimenter to choose and change detector settings. They don't recognize non-arbitrarily-chosen initial conditions. They really don't understand physical measure space -- they take it to be the quantum configuration space -- and since the conclusion of Bell's Theorem is that quantum configuration space cannot map onto physical space without a nonlocal model, non-locality is a prior assumption.

To prove it -- ask a Bell believer to define a measure space. Should be simple enough -- in what space are Bell-Aspect measures taken?

Hi Tom,

We are just talking about the realism part of the equation here not the locality part. So Joy's S^3 model is perfectly realistic since it predicts correlation when a = b and anti-correlation when a = -b and also predicts 50-50 +/- 1 outcomes at A and B via realistic means for the EPR-Bohm scenario. It does not have to predict what the individual event by event outcomes might be.
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Q-reeus wrote:Slightly off-topic. This link posted recently at another site: http://thebigbelltest.org/

A bit late to participate it seems, not that anyone here would be particularly keen I'd imagine! Got to wonder what level of education was being aimed at - trippy if nothing else.

minkwe wrote:
Tom according to EPR, realism is defined as -- If a theory can predict with certainty the result of a measurement, without disturbing the system then there is an element of reality corresponding to the measured quantity in the theory.

If the theory predicts that measurement at (a=b) will produce perfect anti-correlation, and measurement in fact produces anti-correlation, then the theory is realistic and has been proven experimentally.

But as Joy has been explaining, Bell assumed that B + B' was an element of realism in LR theories. The question so far unanswered by Bell believers is: "What is the prediction that Bell-LR theories make for measurement of the impossible B + B' quantity.

In effect, Bell concluded that LR theories were impossible by including an impossible element of realism in the assumptions. The reason experiments can't confirm Bell's realism, is because his realism includes impossible quantities such as B + B', that can never be measured in the first place.

Joy Christian wrote:
For convenience, here is how EPR would specify “elements of reality” for the singlet state:

The singlet state has two remarkable properties. First, it happens to be rotationally invariant. That is to say, it remains the same for all directions in space, denoted by the unit vector n. Second, it entails perfect spin correlations: If the component of spin along direction n is found to be “up” for particle 1, then with certainty it will be found to be “down” for particle 2, and vice versa. Consequently, one can predict with certainty the result of measuring any component of spin of particle 2 by previously measuring the same component of spin of particle 1. However, locality demands that measurements performed on particle 1 cannot bring about any real change in the remotely situated particle 2. Therefore, according to the criterion of reality, the chosen spin component of particle 2 is an element of physical reality. But this argument goes through for any component of spin, and hence all infinitely many of the spin components of particle 2 are elements of physical reality (cf. the paper by GHSZ).

It is evident to me that B(b) + B(b’ ) is NOT an element of reality according to EPR’s criterion.

minkwe wrote:Tom according to EPR, realism is defined as -- If a theory can predict with certainty the result of a measurement, without disturbing the system then there is an element of reality corresponding to the measured quantity in the theory.

If the theory predicts that measurement at (a=b) will produce perfect anti-correlation, and measurement in fact produces anti-correlation, then the theory is realistic and has been proven experimentally.

But as Joy has been explaining, Bell assumed that B + B' was an element of realism in LR theories. The question so far unanswered by Bell believers is: "What is the prediction that Bell-LR theories make for measurement of the impossible B + B' quantity.

In effect, Bell concluded that LR theories were impossible by including an impossible element of realism in the assumptions. The reason experiments can't confirm Bell's realism, is because his realism includes impossible quantities such as B + B', that can never be measured in the first place.

Joy Christian
Jay, as you probably know, I would not use your (14) as a criterion for the elements of reality. So my answers to your questions in Part A and Part B are both in the negative, with more negative for the question in Part B for obvious reasons.
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FD wrote:That is correct and applied to the EPR-Bohm situation, A, B, A’ and B’ cannot be elements of reality until they are measured. The best any theory can do is predict that their averages will be zero after many trials.

FrediFizzx wrote:Posted at RW which they did not let thru so far,

Joy Christian
Jay, as you probably know, I would not use your (14) as a criterion for the elements of reality. So my answers to your questions in Part A and Part B are both in the negative, with more negative for the question in Part B for obvious reasons.
…

FD wrote:That is correct and applied to the EPR-Bohm situation, A, B, A’ and B’ cannot be elements of reality until they are measured. The best any theory can do is predict that their averages will be zero after many trials.

That should really end the debate about "elements of reality" as far as Bell's theory goes. No one can make a prediction with 100 percent certainty for A, B, A', B' therefore they have to be measured. And since it is impossible to measure B + B' simultaneously, it can never be an element of reality. Bell's theory is junk physics as far as realism goes.
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Joy Christian wrote:

FrediFizzx wrote:Posted at RW which they did not let thru so far,

Joy Christian
Jay, as you probably know, I would not use your (14) as a criterion for the elements of reality. So my answers to your questions in Part A and Part B are both in the negative, with more negative for the question in Part B for obvious reasons.
…

FD wrote:That is correct and applied to the EPR-Bohm situation, A, B, A’ and B’ cannot be elements of reality until they are measured. The best any theory can do is predict that their averages will be zero after many trials.

That should really end the debate about "elements of reality" as far as Bell's theory goes. No one can make a prediction with 100 percent certainty for A, B, A', B' therefore they have to be measured. And since it is impossible to measure B + B' simultaneously, it can never be an element of reality. Bell's theory is junk physics as far as realism goes.
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Not quite, Fred. Alice can predict Bob's result B(b) with certainty by measuring A(b), since there is perfect anti-correlation between B(b) and A(b); i.e., A(b)B(b) = -1.

***

FrediFizzx wrote:

Joy Christian wrote:
Not quite, Fred. Alice can predict Bob's result B(b) with certainty by measuring A(b), since there is perfect anti-correlation between B(b) and A(b); i.e., A(b)B(b) = -1.

***

Yes, Michel already addressed that. That prediction can only be when a = b or a = -b. With any other arbitrary b, Alice cannot predict what Bob will get. But as Michel points out, it is sufficient that if any hidden variable theory does predict anti-correlation or correlation when a = b or a = -b then it can be considered a realistic theory. I think he is right.
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Joy Christian wrote:

FrediFizzx wrote:

Joy Christian wrote:
Not quite, Fred. Alice can predict Bob's result B(b) with certainty by measuring A(b), since there is perfect anti-correlation between B(b) and A(b); i.e., A(b)B(b) = -1.
***

Yes, Michel already addressed that. That prediction can only be when a = b or a = -b. With any other arbitrary b, Alice cannot predict what Bob will get. But as Michel points out, it is sufficient that if any hidden variable theory does predict anti-correlation or correlation when a = b or a = -b then it can be considered a realistic theory. I think he is right.
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Yes, Michel is right. That follows from the EPR criterion of reality, when applied to the singlet state.

***

FrediFizzx wrote:

Joy Christian wrote:

FrediFizzx wrote:

Joy Christian wrote:
Not quite, Fred. Alice can predict Bob's result B(b) with certainty by measuring A(b), since there is perfect anti-correlation between B(b) and A(b); i.e., A(b)B(b) = -1.
***

Yes, Michel already addressed that. That prediction can only be when a = b or a = -b. With any other arbitrary b, Alice cannot predict what Bob will get. But as Michel points out, it is sufficient that if any hidden variable theory does predict anti-correlation or correlation when a = b or a = -b then it can be considered a realistic theory. I think he is right.
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Yes, Michel is right. That follows from the EPR criterion of reality, when applied to the singlet state.

***

Well, this fact takes a bit of "pressure" off your model since you make that prediction plus can make the prediction that the averages of A(a, lambda) and B(b, lambda) will be zero after many trials. You can put in the effect of the polarizers and the model is still perfectly local-realistic. The model doesn't have to predict individual event by event outcomes. Which are impossible in the EPR-Bohm scenario anyways. But the bottom line as far as realism goes, is that it is impossible for B + B' to be an element of reality taking EPR-Bohm into consideration.
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Joy Christian wrote:The GA model predicts the individual +/-1 also. ***

FrediFizzx wrote:

Joy Christian wrote:The GA model predicts the individual +/-1 also. ***

Hmm... I don't think so as the effect of the polarizers is not included, IIRC. I will have to look at the simulation again.

But it doesn't have to predict the individual event by event outcomes to be completely local-realistic is the new point I am making.