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arXiv · 1311.3908

A characterization theorem for matrix variances

Dénes Petz·Dániel Virosztek
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Abstract

Some recent papers formulated sufficient conditions for the decomposition of matrix variances. A statement was that if we have one or two observables, then the decomposition is possible. In this paper we consider an arbitrary finite set of observables and we present a necessary and sufficient condition for the decomposition of the matrix variances.

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Dénes Petz, Dániel Virosztek. 2014-07-01. A characterization theorem for matrix variances. https://doi.org/10.14232/actasm-013-789-z

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