ON QUASI-A(n, κ) CLASS OPERATORS

Title & Authors
ON QUASI-A(n, κ) CLASS OPERATORS
Lee, Mi Ryeong; Yun, Hye Yeong;

Abstract
To study the operator inequalities, the notions of class A operators and quasi-class A operators are developed up to recently. In this paper, quasi-$\small{A(n,{\kappa})}$ class operator for $\small{n{\geq}2}$ and $\small{{\kappa}{\geq}0}$ is introduced as a new notion, which generalizes the quasi-class A operator. We obtain some structural properties of these operators. Also we characterize quasi-$\small{A(n,{\kappa})}$ classes for n and $\small{{\kappa}}$ via backward extension of weighted shift operators. Finally, we give a simple example of quasi-$\small{A(n,{\kappa})}$ operators with two variables.
Keywords
class A;quasi-class A;weighted shift operator;
Language
English
Cited by
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