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What is the value of an observable between pre- and postselection?

Lars M. Johansen
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Abstract

Hall's recent derivation of an exact uncertainty relation [Phys. Rev. A64, 052103 (2001)] is revisited. It is found that the Bayes estimator of an observable between pre- and postselection equals the real part of the weak value. The quadratic loss function equals the expectation of the squared imaginary part of the weak value.

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Lars M. Johansen. 2004-02-07. What is the value of an observable between pre- and postselection?. https://doi.org/10.1016/j.physleta.2004.01.041

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