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arXiv · 1210.2922

Decomposition and partial trace of positive matrices with Hermitian blocks

Jean-Christophe Bourin·Eun-Young Lee
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Abstract

Let H be a positive semidefinite matrix partitioned into Hermitian blocks. Then, up to a direct sum operation, H is the average of matrices isometrically congruent to its partial trace. A few corollaries are given, related to important inequalities in quantum information theory such as the Nielsen-Kempe separability criterion.

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Jean-Christophe Bourin, Eun-Young Lee. 2012-10-11. Decomposition and partial trace of positive matrices with Hermitian blocks. https://arxiv.org/abs/1210.2922

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