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arXiv · 2210.05535

S-spectrum and numerical range of a quaternionic operator

Luís Carvalho·Cristina Diogo·Sérgio Mendes
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Abstract

We study the numerical range of bounded linear operators on quaternionic Hilbert spaces and its relation with the S-spectrum. The class of complex operators on quaternionic Hilbert spaces is introduced and the upper bild of normal complex operators is completely characterized in this setting.

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Luís Carvalho, Cristina Diogo, Sérgio Mendes. 2022-10-11. S-spectrum and numerical range of a quaternionic operator. https://arxiv.org/abs/2210.05535

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