Fredholm theory for demicompact linear relations

Authors

  • Aymen Ammar University of Sfax
  • Slim Fakhfakh University of Sfax
  • Aref Jeribi University of Sfax

DOI:

https://doi.org/10.4995/agt.2022.16940

Keywords:

demicompact linear relations, Fredholm theory, block matrix

Abstract

We first attempt to determine conditions on a linear relation T such that μT becomes a demicompact linear relation for each μ ∈ [0,1)(see Theorems 2.4 and 2.5). Second, we display some results on Fredholm and upper semi-Fredholm linear relations involving a demicompact one(see Theorems 3.1 and 3.2). Finally, we provide some results in which a block matrix of linear relations becomes a demicompact block matrix of linear relations (see Theorems 4.2 and 4.3).

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Author Biographies

Aymen Ammar, University of Sfax

Department of mathematics, Faculty of Sciences of Sfax

Slim Fakhfakh, University of Sfax

Department of Mathematics, Faculty of Sciences of Sfax

Aref Jeribi, University of Sfax

Department of Mathematics, Faculty of Sciences of Sfax

References

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Published

2022-10-03

How to Cite

[1]
A. Ammar, S. Fakhfakh, and A. Jeribi, “Fredholm theory for demicompact linear relations”, Appl. Gen. Topol., vol. 23, no. 2, pp. 425–436, Oct. 2022.

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