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Realism in the vein of EPR and Bell

 
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Jan3-13, 01:04 PM   #18
mbd
 

Realism in the vein of EPR and Bell


DrChinese, I am very sorry for having gone out of my way to create an extremely simple, no math necessary, self-evident, example of a system that can violate Bell's Inequality.

My intent: to advance understanding of Bell's Theorem, CHSH experiments, and their assumptions.

I also provided links above to peer-reviewed articles that explore and define the assumptions and loopholes, and present mathematical models that demonstrate the potential of these loopholes.

In contrast, you have misrepresented the state of the science, presented unclear, ambiguous, and inaccurate definitions, dismissed peer-reviewed articles on the basis of your personal opinions, and you have consistently misquoted and mischaracterized the posts of folks using this forum in good faith who disagree with you.
Jan3-13, 01:09 PM   #19
 
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Quote by mbd View Post
DrChinese, I am very sorry for having gone out of my way to create an extremely simple, no math necessary, self-evident, example of a system that can violate Bell's Inequality.
The "counter-example" fails as I have detailed. And it is hardly self-evident. You may as well say it is self-evident that 1=0. I have commented on each of your references. None of these have anything whatsoever to do with your personal local realistic theories.

Last chance: retract or provide the specifics.
Jan3-13, 01:17 PM   #20
 
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Quote by jk22 View Post
In QM treatment of EPRB it is seen from the onset that the measurement disturbs the system since suppose we measure 1st particle with + then
psi_before equals ((+-)-(-+))/sqrt2 and
psi_after equals* (+-)
since both differ we conclude there was a disturbance.

Hence we cannot use the EPR criterion of existence of elem. of phys. reality.
You have made a good point, and I am sure Bohr would agree with you! In QM the system is disturbed.

However, if you ASSUME that there was no such disturbance (as EPR does), then the criterion applies. (Of course there was something of a circular nature to the EPR argument.) They say:

"On the other hand, since at the time of measurement the two systems no longer interact, no real change can take place in the second system in consequence of anything that may be done to the first system."
Jan3-13, 02:05 PM   #21
mbd
 
Quote by DrChinese View Post
You have made a good point, and I am sure Bohr would agree with you! In QM the system is disturbed.

However, if you ASSUME that there was no such disturbance (as EPR does), then the criterion applies. (Of course there was something of a circular nature to the EPR argument.) They say:

"On the other hand, since at the time of measurement the two systems no longer interact, no real change can take place in the second system in consequence of anything that may be done to the first system."
There is nothing circular about the EPR argument. It is a standard proof by contradiction.

The assumption is that special relativity applies to all physical phenomena. With this assumption, measuring the first cannot change the second. QM, though, predicts a change to the second. So, either special relativity does not exclude "spooky action" or QM is an incomplete theory.
Jan3-13, 02:35 PM   #22
 
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Quote by mbd View Post
There is nothing circular about the EPR argument. It is a standard proof by contradiction.

The assumption is that special relativity applies to all physical phenomena. With this assumption, measuring the first cannot change the second. QM, though, predicts a change to the second. So, either special relativity does not exclude "spooky action" or QM is an incomplete theory.
Wrong again! EPR says that if their assumptions are correct, then QM is incomplete. That is circular reasoning because their assumptions will be contested by reasonable people. For an assumption to work, it must be agreeable to someone contesting (ie agreeable to both sides).

EPR assumes no action at a distance - such as QM's application of the HUP non-locally - and concludes QM is incomplete. That conclusion is not generally accepted and never has been (although there were a number of scientists who accepted this early on).

What was accepted from EPR is that IF QM is complete, then the reality of a particle here is dependent on the nature of a measurement there. This is now generally accepted as being the case, although that assessment is somewhat more recent (post Bell).
Jan3-13, 03:44 PM   #23
 
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