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arXiv · 1308.3332

A decomposition theorem for positive maps, and the projection onto a spin factor

Erling Størmer
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Abstract

It is shown that each positive map between matrix algebras is the sum of a maximal decomposable map and an atomic map which is both optimal and co-optimal. The result is analyzed in detail for the positive projection onto a spin factor.

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Erling Størmer. 2013-08-16. A decomposition theorem for positive maps, and the projection onto a spin factor. https://arxiv.org/abs/1308.3332

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