Polynomially partial isometric operators

Year 2023, , 151 - 162, 15.02.2023

Dijana Mosic

https://doi.org/10.15672/hujms.1074783

Cited By: 1

Abstract

In order to extend the notion of semi-generalized partial isometries and partial isometries, we introduce a new class of operators called polynomially partial isometries. Since this new class of operators contains semi-generalized partial isometries, partial isometries, isometries and co-isometries, we proposed a wider class of operators. Several basic properties of polynomially partial isometries and some invariant subspaces of corresponding operators are presented. We study decomposition theorems and spectral theorems for polynomially partial isometries, generalizing some well-known results for partial isometries and semi-generalized partial isometries to polynomially partial isometries. Applying polynomially partial isometries, we solve some equations.

Keywords

partial isometry, isometry, decomposition theorem, Hilbert space

Supporting Institution

Ministry of Education, Science and Technological Development, Republic of Serbia

Project Number

451-03-68/2022-14/200124

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