On isolated points of the approximate point spectrum of a closed linear relation

Authors

  • Melik Lajnef Department of Mathematics, University of Sfax. Faculty of Sciences of Sfax, Route de Soukra Km 3.5. B.P. 1171, 3000, Sfax, Tunisia
  • Maher Mnif Department of Mathematics, University of Sfax. Faculty of Sciences of Sfax, Route de Soukra Km 3.5. B.P. 1171, 3000, Sfax, Tunisia

DOI:

https://doi.org/10.17398/2605-5686.37.1.75

Keywords:

Linear relation, isolated point of the approximate point spectrum, analytic core, quasinilpotent part

Abstract

We investigate in this paper the isolated points of the approximate point spectrum of a closed linear relation acting on a complex Banach space by using the concepts of quasinilpotent part and the analytic core of a linear relation.

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References

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Published

2022-06-01

Issue

Section

Operator Theory

How to Cite

On isolated points of the approximate point spectrum of a closed linear relation. (2022). Extracta Mathematicae, 37(1), 75-90. https://doi.org/10.17398/2605-5686.37.1.75