A theoretical investigation of S-Numerical Range with the respect to a family of projections

Authors

  • Wlat Hamad Department of Mathematics, Faculty of Education, Soran University, Soran, Erbil, Kurdistan Region, Iraq
  • Department of Mathematics, Faculty of Education, Soran University, Soran, Erbil, Kurdistan Region, Iraq

DOI:

https://doi.org/10.21271/ZJPAS.34.6.4

Keywords:

S-numerical range, projections, spectrum, bounded operator

Abstract

The idea of the -numerical range of a bounded linear operator on a complex Hilbert space with respect to a family of projections is introduced in this study. We provide a detailed description and discuss its relationship to the -numerical range and generalizations such as product S-numerical range. The significance of this new concept comes from its unifying character.

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Published

2022-12-20

Issue

Section

Mathematics ,Physics and Engineering Researches