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Convex domains and K-spectral sets

Catalin Badea·Michel Crouzeix·Bernard Delyon
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Abstract

Let $Ω$ be an open convex domain of the complex plane. We study constants K such that $Ω$ is K-spectral or complete K-spectral for each continuous linear Hilbert space operator with numerical range included in $Ω$. Several approaches are discussed.

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Catalin Badea, Michel Crouzeix, Bernard Delyon. 2005-04-14. Convex domains and K-spectral sets. https://arxiv.org/abs/math/0501184

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