The minimum entropy output of a quantum channel is locally additive

Gilad Gour; Shmuel Friedland

doi:10.1109/tit.2012.2210859

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arXiv · 1105.6122

The minimum entropy output of a quantum channel is locally additive

Gilad Gour·Shmuel Friedland

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Abstract

We show that the minimum von-Neumann entropy output of a quantum channel is locally additive. Hasting's counterexample for the additivity conjecture, makes this result quite surprising. In particular, it indicates that the non-additivity of the minimum entropy output is a global effect of quantum channels.

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Gilad Gour, Shmuel Friedland. 2011-12-14. The minimum entropy output of a quantum channel is locally additive. https://doi.org/10.1109/tit.2012.2210859

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