Finite Rank and Small Perturbations of Linear Relations

  • Ezzeddine ChafaiEmail author
  • Teresa Álvarez


In this paper, we investigate the stability of regular, semi-Fredholm, finite essential ascent and finite essential descent linear relations under small and commuting finite rank perturbations as well as the behavior of the nullity, the defect and the index under such perturbations.


Linear relation Regular and semi-Fredholm linear relations Essential ascent Essential descent 

Mathematics Subject Classification

47A06 47A53 47A10 



The work of Teresa Álvarez was supported by Micinn (Spain). Grant MTM 2013-45643.


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Copyright information

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Authors and Affiliations

  1. 1.Department of MathematicsPrince Sattam Bin Abdulaziz UniversityAl-KharjSaudi Arabia
  2. 2.Department of Mathematics, Faculty of Sciences of SfaxUniversity of SfaxSfaxTunisia
  3. 3.Department of MathematicsUniversity of OviedoOviedoSpain

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