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ON WEIGHTED AND PSEUDO-WEIGHTED SPECTRA OF BOUNDED OPERATORS

  • Athmouni, Nassim (Department of Mathematics Faculty of Sciences of Gafsa University of Gafsa) ;
  • Baloudi, Hatem (Department of Mathematics Faculty of Sciences of Gafsa University of Gafsa) ;
  • Jeribi, Aref (Department of Mathematics Faculty of Sciences of Sfax University of Sfax) ;
  • Kacem, Ghazi (Department of Mathematics Faculty of Sciences of Sfax University of Sfax)
  • Received : 2017.06.09
  • Accepted : 2017.12.21
  • Published : 2018.07.31

Abstract

In the present paper, we extend the main results of Jeribi in [6] to weighted and pseudo-weighted spectra of operators in a nonseparable Hilbert space ${\mathcal{H}}$. We investigate the characterization, the stability and some properties of these weighted and pseudo-weighted spectra.

Keywords

Fredholm operators;${\alpha}-Fredholm$ operator;pseudo-spectrum;weighted spectrum

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