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arXiv · 1304.0054

Lüders Theorem for Unsharp Quantum Measurements

Paul Busch·Javed Singh
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Abstract

A theorem of Lüders states that an ideal measurement of a sharp discrete observable does not alter the statistics of another sharp observable if, and only if, the two observables commute. It will be shown that this statement extends to certain pairs of unsharp observables. Implications for local relativistic quantum theory will be discussed.

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Paul Busch, Javed Singh. 2013-03-30. Lüders Theorem for Unsharp Quantum Measurements. https://doi.org/10.1016/s0375-9601(98)00704-x

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