Pseudo Numerical Ranges and Spectral Enclosures.

Borbala Gerhat1, Christiane Tretter1

  • 1Math. Institut, Universität Bern, Sidlerstr. 5, 3012 Bern, Switzerland.

Complex Analysis and Operator Theory
|July 5, 2022
PubMed
Summary

This study introduces pseudo numerical ranges and pseudo block numerical ranges for operator functions and matrices. These new concepts provide improved spectral enclosures for operator matrices and damped wave equations.

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