COWEN SETS FOR TOEPLITZ OPERATORS

被引：0

作者：

Kim, Hyoung Joon ^{[1
]}

Park, Jaehui ^{[2
]}

机构：

[1] Seoul Natl Univ, Dept Math Sci, Seoul 08826, South Korea

[2] Seoul Natl Univ, Res Inst Math, Seoul 08826, South Korea

来源：

OPERATORS AND MATRICES | 2023年 / 17卷 / 02期

关键词：

Cowen sets; hyponormal operators; Toeplitz operators;

D O I：

10.7153/oam-2023-17-25

中图分类号：

O1 [数学];

学科分类号：

0701 ; 070101 ;

摘要：

The Cowen set for  E L  is defined by E () = {k E H  : k  1,  - k  E H }. It is known that the Toeplitz operator T  is hyponormal if and only if E () is nonempty. In this paper, we study various properties of Cowen sets. Especially, we investigate in detail the case when E () contains a constant and find a condition where E () consists of exactly one constant.

引用

页码：355 / 365

页数：11

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