Stability of relative essential spectra involving relative demicompactness concept in Banach subalgebra-Reference-Cited by-同舟云学术

Stability of relative essential spectra involving relative demicompactness concept in Banach subalgebra

Published:2023 Issue:3 Volume:37 Page:891-903
ISSN:0354-5180
Container-title:Filomat
language:en
Short-container-title:Filomat

Author:

Chelly Slim¹

Affiliation:

1. Department of Mathematics, Faculty of Sciences of Sfax, University of Sfax, Sfax, Tunisia

Abstract

This paper develops the notion of relative demicompact elements of an algebra with respect to a Banach subalgebra as a generalization of relative demicompact linear operators acting on Banach spaces. Drawing on this novel notion, we build a new class of Fredholm perturbation regarding a given Banach subalgebra B which contains its inessential ideal kB and the set of left Fredholm perturbations suggested in [6]. The developed class of Fredholm perturbation exhibits that is a two-sided closed ideal of B that is key in the characterization of the weyl spectrum of elements affiliated with B.

Publisher

National Library of Serbia

Subject

General Mathematics

Reference20 articles.

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