Elementary constructive approach to the higher-rank numerical ranges of unitary matrices

A. Ya. Kazakov

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arXiv · 0707.0170

Elementary constructive approach to the higher-rank numerical ranges of unitary matrices

A. Ya. Kazakov

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Abstract

Some problems of the quantum error-correcting codes theory can be reduced to the investigation of the higher-rank numerical ranges of the operators related to the error operators. We constructively verify a conjecture on the structure of higher-rank numerical range for unitary matrices.

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A. Ya. Kazakov. 2007-07-02. Elementary constructive approach to the higher-rank numerical ranges of unitary matrices. https://arxiv.org/abs/0707.0170

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