NUMERICAL RANGES OF SOME FOGUEL OPERATORS

被引:0
作者
Jiang, Muyan [1 ]
Spitkovsky, Ilya M. [1 ]
机构
[1] New York Univ Abu Dhabi NYUAD, Div Sci & Math, POB 129188, Abu Dhabi, U Arab Emirates
来源
OPERATORS AND MATRICES | 2023年 / 17卷 / 01期
关键词
Numerical range; Foguel operator; Toeplitz operator; Schur complement;
D O I
10.7153/oam-2023-17-14
中图分类号
O1 [数学];
学科分类号
0701 ; 070101 ;
摘要
The Foguel operator is defined as FT = [S* T], where S is the right shift on a Hilbert 0 S space 7-l and T is an arbitrary bounded linear operator acting on 7-l. Obviously, the numerical range W (F0) of FT with T = 0 is the open unit disk, and it was suggested by Gau, Wang and Wu in their Linear Algebra and Applications (2021) paper that W (FaI) for non-zero a E C might be an elliptical disk. In this paper, we described W (FaI) explicitly and, as it happens, it is not.
引用
收藏
页码:179 / 185
页数:7
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