On the sum of normal matrices

Minghua Lin

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arXiv · 1202.1207

On the sum of normal matrices

Minghua Lin

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Abstract

This short paper revisits a remarkable but almost overlooked result of Djokovi\'{c} [Proc. Amer. Math. Soc. 27 (1971) 19-23]. A connection to a result of \u{S}emrl is pointed out. With Djokovi\'{c}'s result, an extension of Craig-Sakamoto theorem to $k$ ($k\ge 2$) normal matrices is presented. A comment to a recent monthly problem is also given.

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Minghua Lin. 2012-02-06. On the sum of normal matrices. https://arxiv.org/abs/1202.1207

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