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arXiv · 1803.10516

A note on the maximal numerical range

Ilya M Spitkovsky
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Abstract

We show that the maximal numerical range of an operator has a non-empty intersection with the boundary of its numerical range if and only if the operator is normaloid. A description of this intersection is also given.

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Ilya M Spitkovsky. 2018-03-28. A note on the maximal numerical range. https://arxiv.org/abs/1803.10516

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