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ON THE STRUCTURE OF COVARIANT PHASE OBSERVABLES

Juha-Pekka Pellonpää

Published Jan 1, 2001• 11 citations
OpenAlex

Abstract

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-Nikod´ym derivatives of phase probability measures are studied. 1.

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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-Nikod´ym derivatives of phase probability measures are studied. 1.
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