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arXiv · 2009.09303

Spectrum of Weighted Composition Operators Part VI Essential spectra of $d$-endomorphisms of Banach $C(K)$-modules

Arkady Kitover·Mehmet Orhon
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Abstract

We investigate properties of essential spectra of disjointness preserving operators acting on Banach $C(K)$-modules. In particular, we prove that under some very mild conditions the upper semi-Fredholm spectrum of such an operator is rotation invariant. In the last part of the paper we provide a full description of the spectrum and the essential spectra of operators acting on Kaplansky modules of the form $T = wU$, where $w \in C(K)$, $U$ is a $d$-isomorphism, and the spectrum of $U$ is a subset of the unit circle.

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Arkady Kitover, Mehmet Orhon. 2020-09-19. Spectrum of Weighted Composition Operators Part VI Essential spectra of $d$-endomorphisms of Banach $C(K)$-modules. https://arxiv.org/abs/2009.09303

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