Communications of the Korean Mathematical Society (대한수학회논문집)

Korean Mathematical Society (대한수학회)
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JOINT ESSENTIAL NUMERICAL SPECTRUM AND JERIBI ESSENTIAL NUMERICAL SPECTRUM OF LINEAR OPERATORS IN BANACH SPACES

  • Bouthaina Abdelhedi (Department of Mathematics Faculty of Sciences of Sfax University of Sfax) ;
  • Wissal Boubaker (Department of Mathematics Faculty of Sciences of Sfax University of Sfax) ;
  • Nedra Moalla (Department of Mathematics Faculty of Sciences of Sfax University of Sfax)
  • Received : 2022.01.29
  • Accepted : 2023.06.07
  • Published : 2023.10.31
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Abstract

The purpose of this paper is to introduce the concept of joint essential numerical spectrum 𝜎en(·) of q-tuple of operators on a Banach space and to study its properties. This notion generalize the notion of the joint essential numerical range.

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References

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