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Demicompact linear operator. Essential pseudospectra and perturbation

  • Aymen Ammar , Houcem Daoud und Aref Jeribi EMAIL logo
Veröffentlicht/Copyright: 26. Juni 2024
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Abstract

In this paper, we give new results on demicompact linear operators, study some properties and some results on Fredholm and upper semi-Fredholm relations involving demicompact operators. Our results are used to provide a fine description of the essential pseudospectra.

MSC 2020: 47A53

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Received: 2023-01-10
Accepted: 2024-02-28
Published Online: 2024-06-26
Published in Print: 2025-02-01

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Heruntergeladen am 24.9.2025 von https://www.degruyterbrill.com/document/doi/10.1515/gmj-2024-2032/html
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