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arXiv · 1208.1029

A Note Concerning von Neumann Projector Measurement Pointer States, Weak Values, and Interference

A. D. Parks·J. E. Gray
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Abstract

It is well known that the pointer state |Φ> resulting from the von Neumann measurement of a projection operator A performed upon an ensemble of quantum systems in the preselected state |ψ> depends upon A|ψ>. Here it is shown that the pointer state |Ψ> obtained from such a measurement performed upon an ensemble that is also postselected depends upon the weak value of A - regardless of the measurement interaction strength. It is also found that, while the spatial distribution of |Ψ> exhibits interference, the idempotency of A prohibits interference in that of |Φ>. This is explained in terms of welcher Weg information.

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A. D. Parks, J. E. Gray. 2012-08-05. A Note Concerning von Neumann Projector Measurement Pointer States, Weak Values, and Interference. https://arxiv.org/abs/1208.1029

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