EPR Debate: Nature Agrees with Einstein

[RandallB]

Dr C
Cat is referring to the link you originally provided in post #119
http://scotty.quantum.physik.uni-muenchen.de/exp/psrc/entangle.html
(Not sure what wrong with Cat’s link)
This is the one where “in our eyes” the scale seemed off. Your post #128
The scale measures the angle of the ½ wave filter; to translate to polarization angles, the bottom alignment angles need to be doubled! Thus we get 100% correlation at 0 and 90 degrees and also at 45 and 135 (AKA -45) degrees.

Now as Hans pointed out in his post #131. The most important part of the “Spectral Distribution” page of this site is how it shows that “Entanglement” can exist with KNOWN polarities, in areas of the cones not on the intersections!. Testing will show the cones produce FIXED polarity photons in the “known” areas. And I’m quite satisfied that testing on entanglement points not on the intersections (‘entanglement’ with known polarities) will successfully produce the same results as on the “Entanglement” page.

QM still has no problem using the $$\psi$$ formula to predict 100% for both 0/90 and 45/-45 in an A-B test.
But that formula is NOT available to the LR.!
The LR must get 100% at 0/90, But I see 50% as the only option for the 45/-45 part of the A-B test for the LR. For a net 75% LR prediction on the A-B test! I’ve been unable to find any justification for any other LR prediction. And this prediction would be the same for known and unknown polarity with ‘entanglement. Now since the Bell proof relies on a 100% prediction by the LR for A-B testing, I don’t see how I can accept Bell.

Although the tests results posted on that Web site are more directed at using Bell to confirm the quality of their method of producing “Entanglement”. There is enough raw data there to convince me that Bell does not satisfy rejecting EPR.
But rather that the A-B test, standing on its own with no need to even run the A-C part (or use BELL), most clearly demonstrates that there is a huge and unresolved conflict (75% vs. 100%) between EPR and QM.

So as you put it:

2. You can construct a local realistic theory that gives 100% correlation at 0 degrees.

AND only if such a theory is used, is Bell useful!
It’s a mystery to me, what is that LR theory that gives 100% during the A-B test?

 

[DrChinese]

Dr C
Cat is referring to the link you originally provided in post #119
http://scotty.quantum.physik.uni-muenchen.de/exp/psrc/entangle.html
(Not sure what wrong with Cat’s link)
This is the one where “in our eyes” the scale seemed off. Your post #128
The scale measures the angle of the ½ wave filter; to translate to polarization angles, the bottom alignment angles need to be doubled! Thus we get 100% correlation at 0 and 90 degrees and also at 45 and 135 (AKA -45) degrees.

Now as Hans pointed out in his post #131. The most important part of the “Spectral Distribution” page of this site is how it shows that “Entanglement” can exist with KNOWN polarities, in areas of the cones not on the intersections!. Testing will show the cones produce FIXED polarity photons in the “known” areas. And I’m quite satisfied that testing on entanglement points not on the intersections (‘entanglement’ with known polarities) will successfully produce the same results as on the “Entanglement” page.

QM still has no problem using the $$\psi$$ formula to predict 100% for both 0/90 and 45/-45 in an A-B test.
But that formula is NOT available to the LR.!
The LR must get 100% at 0/90, But I see 50% as the only option for the 45/-45 part of the A-B test for the LR. For a net 75% LR prediction on the A-B test! I’ve been unable to find any justification for any other LR prediction. And this prediction would be the same for known and unknown polarity with ‘entanglement. Now since the Bell proof relies on a 100% prediction by the LR for A-B testing, I don’t see how I can accept Bell.

Although the tests results posted on that Web site are more directed at using Bell to confirm the quality of their method of producing “Entanglement”. There is enough raw data there to convince me that Bell does not satisfy rejecting EPR.
But rather that the A-B test, standing on its own with no need to even run the A-C part (or use BELL), most clearly demonstrates that there is a huge and unresolved conflict (75% vs. 100%) between EPR and QM.

So as you put it:
AND only if such a theory is used, is Bell useful!
It’s a mystery to me, what is that LR theory that gives 100% during the A-B test?

We're wandering all over the place here.

First, I didn't write this page per the link. To the extent it is useful, great. It is just a picture so don't get caught up in a literal interpretation. If the scale is off, it is off.

The question for Bell is absolutely NOT can a LR theory that YOU think up give a 100% prediction at 0 degrees. Plenty of folks - Einstein among them - have simply assumed that the probabilistic predictions of QM are correct. Eisntein was also one of the fathers of quantum theory, as you may recall. So he was quite ambivalent about QM. But I don't think you will ever find a reference from him doubting that the statistical spin predictions of QM as simply wrong.

Bell always assumed that the predictions of QM were correct. Almost everyone did. I cannot recall any serious proponent of the position - ever - that QM would yield a wrong prediction in this regard. I am sure plenty of folks held an open mind, but cannot recall anyone actually voicing the expectation that QM was incorrect. You may question it certainly between the period 1935 to 1981 (when Aspect effectively shut the door for good) but most others never gave it as much thought. QM was simply too good.

As previously stated, the point of Bell was to demonstrate - to those who thought the predictions of QM could be neatly accommodated by some to-be-determined future LR theory - that they were flat wrong. If you don't hold this position, then Bell is not for you. Since plenty of famous physicists DID hold such a view, the Bell paper did matter. Today it is widely referenced.

You still cannot support local reality. Per your logic, LR cannot do better than 75% at 0 degrees. Fine. The experimental evidence is 100% so your LR is ruled out, end of subject. You are trying to apply logic to the LR position, and the true LR position all along has been "we will discover the truth in the future to prove our position correct". After Bell that position fell apart and no experiment was needed to cause it to fall apart. You cannot have your cake and eat it too.

As to the PDC cones: if the cones generate fixed polarization outside the area of intersection, also fine. The photons are not entangled there and those photons are masked out of the test. Once you have a mixed state (where there is intersection) then all bets are off. It is the entangled states we want to measure.

Realistically, you should ignore the entire concept of the 75% case, which is throwing you off track. That case ignores entanglement in favor of a naive realism! No one takes it seriously much except those who deny the science of Bell tests, such as Cat, who also deny entanglement, Aspect, double slits, HUP, photons and in most respects the essential philosophy of QM. Cat, have I mistated your postion? :)

 

[Cat]

I couldn't find any graph like the one you described. The link has a number of different slides... can you tell me which one I should reference? I have noticed this link has a bit of difficulty because it seems to come up with different slides for different people. Is it the one where psi2 is measured at 0 and 22.5 degrees?

Yes, that's the one. RandallB has given the correct link: http://scotty.quantum.physik.uni-mu...c/entangle.html .

The difference is not very great but it seems definite enough: the ranges of the two curves are not the same. On its own this might not mean much but, if I remember correctly, we find the same kind of discrepancy in Weihs' graphs. I think this could have the same cause.

A hint as to the explanation of the scale problem is given in Weihs' paper: there are two angular values involved: a phase angle and a geometrical one. A phase difference of 180 deg between H and V components shows up as a geometrical difference of 90 deg in the output from a Wollaston prism. This is a classical wave result, as he says in one of his footnotes.

Cat

 

[RandallB]

We're wandering all over the place here.
----
As to the PDC cones: if the cones generate fixed polarization outside the area of intersection, also fine. The photons are not entangled there and those photons are masked out of the test. Once you have a mixed state (where there is intersection) then all bets are off. It is the entangled states we want to measure.

Realistically, you should ignore the entire concept of the 75% case, which is throwing you off track.

This is the area to focus on to avoid wandering all over.
75% vs 100% is important.

As Hans, I believe the area outside of the intersection DOES provide "entangled" photons and "fixed". See post #131 by Hans. And as I said IF the test is run in the non-intersection area the same 100% correlation will be found when aligned on correct "entangled" points.
I understand that QM-BELL would not expect a result of "entanglement" with KNOWN polierzations. Just as the LR should expect no better tha 75%. Thus IF the result is found to be so, I believe that it would disprove QM-BELL. At least in the photon polarization case, but would not give an opinion on QM alone.

If there is "entanglement" with known polierzations, it could well mean that "entanglement may not really be Entanglement but the result of SOMETHING ELSE that needs a better explanation than we currently have. That is the EPR point.

So is "entanglement" with known polierzations real?
The raw data in the website we are looking at is not directed at answering that question, as they do not show any direct attempt to find them outside the intersections. I know Cat seems to question the value of the data in whole. But for me there is just barely enough data to convice me it is true. I understand for you it may not be enough data to convice you.

SO can we both agree that IF and only IF someone someday can successfully produce 100% correlation in a A-B test for photons outside the intersections, and of cource verify fixed polarization (ie. "entanglement" with known polierzations). That QM-Bell, at least within the photon polarization area, is in trouble?

RB