SPECTRA AND PSEUDOSPECTRA OF THE DIRECT SUM OPERATORS

Year 2020, Volume: 38 Issue: 3, 1251 - 1259, 05.10.2021

Zameddin I. Ismaılov Pembe Ipek Al

Abstract

In this paper, the relationships between spectrum and pseudospectrum of the direct sum of linear operators in the direct sum of Hilbert spaces and its coordinate operators have been researched. Also, the analogous relations of some numerical characteristics (spectral and pseudospectral radii) of such operators have been investigated.

Keywords

Direct sum of operators, spectrum, pseudospectrum, spectral radii

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