Norm-parallelism and the Davis-Wielandt radius of Hilbert space operators

被引：21

作者：

Zamani, Ali ^{[1
]}

Moslehian, Mohammad Sal ^{[2
]}

Chien, Mao-Ting ^{[3
]}

Nakazato, Hiroshi ^{[4
]}

机构：

[1] Farhangian Univ, Dept Math, Tehran, Iran

[2] Ferdowsi Univ Mashhad, CEAAS, Dept Pure Math, Mashhad, Razavi Khorasan, Iran

[3] Soochow Univ, Dept Math, Taipei, Taiwan

[4] Hirosaki Univ, Fac Sci & Technol, Hirosaki, Aomori, Japan

来源：

LINEAR & MULTILINEAR ALGEBRA | 2019年 / 67卷 / 11期

基金：

美国国家科学基金会;

关键词：

Birkhoff-James orthogonality; norm-parallelism; numerical radius; Davis-Wielandt radius; NUMERICAL RADIUS; LOWER BOUNDS; ORTHOGONALITY; INEQUALITIES; MATRICES;

D O I：

10.1080/03081087.2018.1484422

中图分类号：

O1 [数学];

学科分类号：

0701 ; 070101 ;

摘要：

We present a necessary and sufficient condition for the norm-parallelism of bounded linear operators on a Hilbert space. We also give a characterization of the Birkhoff-James orthogonality for Hilbert space operators. Moreover, we discuss the connection between norm-parallelism to the identity operator and an equality condition for the Davis-Wielandt radius. Some other related results are also discussed.

引用

页码：2147 / 2158

页数：12

共 20 条

[1] Orthogonality of matrices and some distance problems [J].