Original EPR Arguments

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Main Question or Discussion Point

In the book "Quantum: Einstein, Bohr, and the Great Debate about the Nature of Reality", the EPR was told in somewhat different way than other sources I have read. I don't know if it is the original views. The arguments goes like this and very simple.

In Copenhagen, In the absense of a measurement to determine its position, the electron has no position. Einstein didn't believe this. So he proposed the EPR thought experiment to show you can measure the position or momentum of A. Since the pair is entangled. B should have the same position or momentum. This, Einstein argued, means B has position or momentum before measurement. This is all Einstein wanted to argue. The book says it was not being argued that both B position and momentum can be known simultaneously because Einstein knew that it was not possible to simultaneously measure its position and momentum. He is only concern about the element of reality which is the position or mometum being definite before measurement.

Bohr countered that before measurement to determine its position or momentum, there is no position or momentum even in principle. It is in the measurement setup that stored that information.

Are the above arguments the real essence of it all? There are many different versions now that are added by different authors and people which made it complicated. I wanted to know the original arguments. Is the book correct that the above arguments I mentioned were the original ones?
 

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I read another book, Heinz Pagels "Quantum Physics as the Language of Nature" and found out the real story.

When you measure the momentum of A and then the position, the previous momentum value would change. This should reach B too if there is non-local influence. Since Einstein doesn't believe in non-local influence, then he believes there is hidden variables.

Bohr countered that there is no properties before measurements and if measurement were done on B. It should have the updated momentum change and reflecting the measurement details of A.

I missed this part because I was actually listening to the audiobook of "Quantum: Einstein, Bohr and the Great Debate of the Nature of Reality". Moral. Avoid listening to audiobooks for technical subjects because you can miss many important details.

Anyway. Reading Heinz Pagels, I came across Bell's Theorem and wondered the following.

Do Aspect Experiment and the like prove that non-local influence with randomness encryption occurs in nature with properties there before measurement or does it prove Bohr original views that properties like position doesn't exist before measurements? Is it:

1. Non-local reality with randomness encryption, or
2. Realism rejected and there is nothing to be non-local about because properties don't exist prior to measurement so no non-local influence at all for non-existent properties.

Which one is the mainstream view??
 

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