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arXiv · 1108.2233

On exposed positive maps: Robertson and Breuer-Hall maps

Dariusz Chruściński
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Abstract

It is well known that so called Breuer-Hall positive maps used in entanglement theory are optimal. We show that these maps possess much more subtle property --- they are exposed. As a byproduct it proves that a Robertson map in the algebra of 4 x 4 complex matrices is not only extreme, which was already shown by Robertson, but also exposed.

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Dariusz Chruściński. 2011-08-10. On exposed positive maps: Robertson and Breuer-Hall maps. https://arxiv.org/abs/1108.2233

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