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arXiv · 1808.00181

On a norm inequality for a positive block-matrix

Tomohiro Hayashi
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Abstract

For a positive semidefinite matrix $H= \begin{bmatrix} A&X\\ X^{*}&B \end{bmatrix} $, we consider the norm inequality $ ||H||\leq ||A+B|| $. We show that this inequality holds under certain conditions. Some related topics are also investigated.

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Tomohiro Hayashi. 2018-08-01. On a norm inequality for a positive block-matrix. https://arxiv.org/abs/1808.00181

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