Abstract
Some recent papers formulated sufficient conditions for the decomposition of matrix variances [6, 10]. 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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Acknowledgement
This work was partially supported by the Hungarian Research Grant OTKA K104206 and we are grateful to Prof. G. Tóth for communication. The authors wish to thank the referees for their constructive comments and advices.
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Communicated by L. Kérchy
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Petz, D., Virosztek, D. A characterization theorem for matrix variances. ActaSci.Math. 80, 681–687 (2014). https://doi.org/10.14232/actasm-013-789-z
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DOI: https://doi.org/10.14232/actasm-013-789-z