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Vol. 46 No. 1 (2020)
Serdica Mathematical Journal

Articles

On extensions of commuting tuples of symmetric and isometric operators

Published 22-06-2020

  • Sergey M. Zagorodnyuk

Sergey M. Zagorodnyuk
V. N. Karazin Kharkiv National University, Ukraine

Abstract

In this paper we study extensions of commuting tuples of symmetric and isometric operators to commuting tuples of self-adjoint and unitary operators. Some conditions which ensure the existence of such extensions are presented. A multidimensional analog of the Godič–Lucenko Theorem is proved. An application to a multidimensional power-trigonometric moment problem is given.

2020 Mathematics Subject Classification:

47A20

Keywords

extensions of operators, symmetric operators, isometric operators, moment problems

Full text

Author Details

Sergey M. Zagorodnyuk

V. N. Karazin Kharkiv National University
School of Mathematics and Computer Sciences
Department of Higher Mathematics and Informatics
Svobody Square 4, 61022, Kharkiv, Ukraine
e-mail: Sergey.M.Zagorodnyuk@gmail.com/ Sergey.M.Zagorodnyuk@univer.kharkov.ua

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