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

Wlat Hamad; Botin Ibrahim

doi:10.21271/ZJPAS.34.6.4

Authors

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