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arXiv · 1012.4221

The automorphism group of separable states in quantum information theory

Shmuel Friedland·Chi-Kwong Li·Yiu-Tung Poon·Nung-Sing Sze
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Abstract

We show that the linear group of automorphism of Hermitian matrices which preserves the set of separable states is generated by \emph{natural} automorphisms: change of an orthonormal basis in each tensor factor, partial transpose in each tensor factor, and interchanging two tensor factors of the same dimension. We apply our results to preservers of the product numerical range.

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Shmuel Friedland, Chi-Kwong Li, Yiu-Tung Poon, Nung-Sing Sze. 2011-04-08. The automorphism group of separable states in quantum information theory. https://doi.org/10.1063/1.3578015

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