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arXiv · quant-ph/0312142

Covariant fuzzy observables and coarse-graining

T. Heinonen·P. Lahti·K. Ylinen
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Abstract

A fuzzy observable is regarded as a smearing of a sharp observable, and the structure of covariant fuzzy observables is studied. It is shown that the covariant coarse-grainings of sharp observables are exactly the covariant fuzzy observables. A necessary and sufficient condition for a covariant fuzzy observable to be informationally equivalent to the corresponding sharp observable is given.

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T. Heinonen, P. Lahti, K. Ylinen. 2003-12-16. Covariant fuzzy observables and coarse-graining. https://doi.org/10.1016/s0034-4877(04)90028-6

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