Stability Theory for Nullity and Deficiency of Linear Relations

Silas Luliro Kito, Gerald Wanjala*

*Corresponding author for this work

Research output: Contribution to journalArticlepeer-review


Let A and B be two closed linear relations acting between two Banach spaces X and Y, and let λ be a complex number. We study the stability of the nullity and deficiency of A when it is perturbed by λB. In particular, we show the existence of a constant ρ>0 for which both the nullity and deficiency of A remain stable under perturbation by λB for all λ inside the disk λ<ρ.

Original languageEnglish
Article number5517215
JournalAbstract and Applied Analysis
Publication statusPublished - 2021
Externally publishedYes

ASJC Scopus subject areas

  • Analysis
  • Applied Mathematics

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