Lower Characteristic and Essential Spectra

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DOI: https://doi.org/10.28924/2291-8639-23-2025-94
Published: Apr 14, 2025
Cite as:
Aref Jeribi, Lower Characteristic and Essential Spectra, Int. J. Anal. Appl., 23 (2025), 94.

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Aref Jeribi

Abstract

In this paper, we show that a lower characteristic linear operator T acting on a Banach space, can be characterized by closed subspace. Some results concerning the essential spectra of the sum of the two bounded linear operators and the essential spectra of each of these operators, where their products are compacts operators on a Banach space X, are given.

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