Acta mathematica scientia, Series B >
APPLICATION OF TWO OPERATORS TRANSFORM FROM CLASS A OPERATOR TO THE CLASS OF HYPONORMAL OPERATOR
Received date: 2007-09-30
Revised date: 2009-05-09
Online published: 2011-01-20
Supported by
The research was supported by Science Foundation of Ministry of Education of China (208081), Technology and pioneering project in Henan Provice (102300410012), and Education Foundation of Henan Province (2007110016, 2008B110006)
In this article, we give an operator transform T(*)from class A operator to the class of hyponormal operators. It is different from the operator transform T defined by M. Ch\={o} and T. Yamazaki. Then, we show that σ(T)=σ{T(*)) and σa(T)\{0}=σa(T(*)) \{0}, in case T belongs to class A. Next, we obtain some relations between T and T(*).
Key words： Class A operator; hyponormal; p-hyponormal; polar decomposition; numerical radius
YANG Chang-Sen , DING Yan-Feng . APPLICATION OF TWO OPERATORS TRANSFORM FROM CLASS A OPERATOR TO THE CLASS OF HYPONORMAL OPERATOR[J]. Acta mathematica scientia, Series B, 2011 , 31(1) : 93 -101 . DOI: 10.1016/S0252-9602(11)60211-7
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