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On the structure of covariant phase observables

Juha-Pekka Pellonpaa
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Abstract

We study the mathematical structure of covariant phase observables. Such an observable can alternatively be expressed as a phase matrix, as a sequence of unit vectors, as a sequence of phase states, or as an equivalent class of covariant trace-preserving operations. Covariant generalized operator measures are defined by structure matrices which form a W*-algebra with phase matrices as its subset. The properties of the Radon-Nikodym derivatives of phase probability measures are studied.

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Juha-Pekka Pellonpaa. 2001-08-23. On the structure of covariant phase observables. https://doi.org/10.1063/1.1446663

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