Some conditions implying normality of operators

被引：8

作者：

Moslehian, M. S. ^{[1
]}

Sales, S. M. S. Nabavi ^{[2
]}

机构：

[1] Ferdowsi Univ Mashhad, CEAAS, Dept Pure Math, Mashhad 91775, Iran

[2] TMRG, Mashhad, Iran

来源：

COMPTES RENDUS MATHEMATIQUE | 2011年 / 349卷 / 5-6期

关键词：

LOG-HYPONORMAL OPERATORS; THEOREM; ROOTS;

D O I：

10.1016/j.crma.2011.01.018

中图分类号：

O1 [数学];

学科分类号：

0701 ; 070101 ;

摘要：

Let T epsilon B(H) and T = U vertical bar T vertical bar be its polar decomposition. We prove that (i) if T is log-hyponormal or p-hyponormal and U-n = U* for some n, then T is normal; (ii) if the spectrum of U is contained in some open semicircle, then T is normal if and only if so is its Aluthge transform (T) over tilde = vertical bar T vertical bar U-1/2 vertical bar T vertical bar(1/2). (C) 2011 Academie des sciences. Published by Elsevier Masson SAS. All rights reserved.

引用

页码：251 / 254

页数：4

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