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Buzz Bloom

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- Has the thought experiment described as the Einstein-Pedolsky-Rosen 1935 "paradox" ever been experimentally explored?

While I have have heard about it for years, I have just read a more-or-less clear description of the EPR "paradox" in David Lindley's

A pair of particles (say A and B) is created which move at the same momentum in opposite directions. A device is set up to measure the position of A. The Heisenberg uncertainty principle requires that the the product of the uncertainty (standard deviation) in position (σ

Assume that the standard deviation σ

It seems plausible that an experiment might be performed similar to the above which would confirm that the change in the value of σ

__Where Does the Weirdness Go?__(1996), page 91, "The fatal blow?". Here is a summary (paraphrasing what I read) as I understand it.A pair of particles (say A and B) is created which move at the same momentum in opposite directions. A device is set up to measure the position of A. The Heisenberg uncertainty principle requires that the the product of the uncertainty (standard deviation) in position (σ

_{x}) and the uncertainty in momentum (σ_{p}) must exceed h/4π.σ

_{x}σ_{p}≥ h/4πh = 6.62607015×10

^{−34}kg m2 / sH = h/4π = 5.29285909×10

There is another device set up to measure B's momentum, some time after A's position is measured.^{−33}kg m2 / sAssume that the standard deviation σ

_{x}of 1,000,000,000 A's measurements is (for example)σ

Assume that if A is _{x}= 5.00000000×10^{−30}m.__not__measured, then the standard deviation σ_{p}of 1,000,000,000 B's measurements is (for example)σ

However, if A and B are measured 1,000,000,000 times, the standard deviation of B's measurements must then be the much greater value_{p}= 5.00000000×10^{−30}kg m / s.σ

_{p}≥ 1.05457182×10^{−3}kg m / s.It seems plausible that an experiment might be performed similar to the above which would confirm that the change in the value of σ

_{p}depends on whether or not A is measured. Does anyone know if such an experiment has ever been performed?