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


  • 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




S-numerical range, projections, spectrum, bounded operator


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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