Hi. I have read a little about the EPR paradox; however I haven’t fully understood it yet, therefore I was hoping for someone to answer my questions, so I can get a better understanding.(adsbygoogle = window.adsbygoogle || []).push({});

I have read the link underneath, however I don’t get it.

http://en.wikipedia.org/wiki/EPR_paradox

Suppose we prepare the system consisting of two particles, A and B, initially interacting with each other but separated far away after that. However, by the help of measurement of one, we can know the state of the other. Here, the point is that this measurement is done when the two cannot interact because of a great separation.

Suppose you measure the momentum of A, then you know the momentum of B as well. Likewise you could measure the position of A and then you know the position of B. However the quantum mechanics implies that the two cannot be real at the same time. So you could either measure the position or the momentum.

Suppose we measure the momentum of A and the position of B, then we both know the momentum and the position for both A and B. However we have just stated that this is not possible. But what could prevent us from measuring it? This measurement is done when the two cannot interact because of a great separation. And even if they could interact with each other, what would happen, which would prevent us from measuring both things?

In wikipedia they use an example with measuring the spin. So what will prevent us from measuring the spin along the z-axis for A, and the spin along the x-axis for B. Again, this measurement is done when the two cannot interact because of a great separation. Then we would know both the spin along the z-axis and x-axis for both A and B. However this is not possible. But what could prevent us from measuring it? And even if A and B could interact which each other, what would happen, which would prevent us from measuring both things?

I hope someone can explain this for me.

Thanks in advance.

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# Einstein-Podolsky-Rosen (EPR) Paradox

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