A note on the maximal numerical range

2018/03/28 by Spitkovsky, Ilya M
#47A12 47B15 #FOS: Mathematics #Functional Analysis (math.FA)

paper · doi:10.48550/arxiv.1803.10516

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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