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Higher-Rank Numerical Ranges and Compression Problems

Man-Duen Choi·David W. Kribs·Karol Zyczkowski
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Abstract

We consider higher-rank versions of the standard numerical range for matrices. A central motivation for this investigation comes from quantum error correction. We develop the basic structure theory for the higher-rank numerical ranges, and give a complete description in the Hermitian case. We also consider associated projection compression problems.

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BibTeXRIS

Man-Duen Choi, David W. Kribs, Karol Zyczkowski. 2006-04-02. Higher-Rank Numerical Ranges and Compression Problems. https://arxiv.org/abs/math/0511278

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