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arXiv · 2004.07533

Numerical range and positive block matrices

Jean Christophe Bourin·Eun-Young Lee
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Abstract

We obtain several norm and eigenvalue inequalities for positive matrices partitioned into four blocks. The results involve the numerical range of the off-diagonal block X, especially the distance from 0 to W(X).

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Jean Christophe Bourin, Eun-Young Lee. 2020-04-16. Numerical range and positive block matrices. https://arxiv.org/abs/2004.07533

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