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arXiv:1704.01905 · Russian Mathematical Surveys

On characterization of positive maps preserving continuity of the von Neumann entropy

Максим Евгеньевич Широков

Published Oct 31, 2016• 1 citation
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Abstract

We show that a positive linear map preserves local continuity (convergence) of the entropy if and only if it preserves finiteness of the entropy, i.e. transforms operators with finite entropy to operators with finite entropy. The last property is equivalent to the boundedness of the output entropy of a map on the set of pure states.
DOI
10.1070/rm9735

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