On Numerical Ranges and Spectra of Norm Attaining Operators in C*-Algebras

Omaoro, Sabasi; Okelo, Benard; Ongati, Omolo

doi:10.28919/cpr-pajm/2-10

Research article

On Numerical Ranges and Spectra of Norm Attaining Operators in C*-Algebras

Sabasi Omaoro, Benard Okelo, Omolo Ongati

Abstract

In this paper, we study norm attaining operators in C∗-algebras. We characterize their numerical ranges and spectra. In particular, we show that if a norm-attaining operator S is self-adjoint, then its spectrum lies in the interval [−||S||, ||S||].

How to cite

S. Omaoro, B. Okelo, O. Ongati, On Numerical Ranges and Spectra of Norm Attaining Operators in C*-Algebras, Pan-Amer. J. Math. 2 (2023), 10. https://doi.org/10.28919/cpr-pajm/2-10

BibTeX

@article{Omaoro2023,
  author  = {Omaoro, Sabasi and Okelo, Benard and Ongati, Omolo},
  title   = {On Numerical Ranges and Spectra of Norm Attaining Operators in C*-Algebras},
  journal = {Pan-Amer. J. Math.},
  volume  = {2},
  year    = {2023},
  pages   = {10},
  doi     = {10.28919/cpr-pajm/2-10}
}