数学物理学报(英文版) ›› 2016, Vol. 36 ›› Issue (5): 1487-1491.doi: 10.1016/S0252-9602(16)30084-4

• 论文 • 上一篇    下一篇

RIESZ IDEMPOTENT OF (n,k)-QUASI-*-PARANORMAL OPERATORS

曾清平1, 钟怀杰2   

  1. 1. College of Computer and Information Sciences, Fujian Agriculture and Forestry University, Fuzhou 350002, China;
    2. School of Mathematics and Computer Science, Fujian Normal University, Fuzhou 350007, China
  • 收稿日期:2014-10-16 修回日期:2016-03-12 出版日期:2016-10-25 发布日期:2016-10-25
  • 作者简介:Qingping ZENG,zqpping2003@163.com;Huaijie ZHONG,zhonghuaijie@sina.com
  • 基金资助:

    This work has been supported by National Natural Science Foundation of China (11301077, 11301078, 11401097, 11501108) and Natural Science Foundation of Fujian Province (2015J01579, 2016J05001).

RIESZ IDEMPOTENT OF (n,k)-QUASI-*-PARANORMAL OPERATORS

Qingping ZENG1, Huaijie ZHONG2   

  1. 1. College of Computer and Information Sciences, Fujian Agriculture and Forestry University, Fuzhou 350002, China;
    2. School of Mathematics and Computer Science, Fujian Normal University, Fuzhou 350007, China
  • Received:2014-10-16 Revised:2016-03-12 Online:2016-10-25 Published:2016-10-25
  • Supported by:

    This work has been supported by National Natural Science Foundation of China (11301077, 11301078, 11401097, 11501108) and Natural Science Foundation of Fujian Province (2015J01579, 2016J05001).

摘要:

A bounded linear operator T on a complex Hilbert space H is called (n, k)-quasi-*-paranormal if ‖T1+n(Tkx)‖1/(1+n)Tkx1/(1+n)≥‖T*(Tkx)‖ for all xH, where n, k are nonnegative integers. This class of operators has many interesting properties and contains the classes of n-*-paranormal operators and quasi-*-paranormal operators. The aim of this note is to show that every Riesz idempotent Eλ with respect to a non-zero isolated spectral point λ of an (n)-quasi-*-paranormal operator T is self-adjoint and satisfies ranEλ=ker(T-λ)=ker(T-λ)*.

关键词: *-class A operator, *-paranormal operator, Riesz idempotent

Abstract:

A bounded linear operator T on a complex Hilbert space H is called (n, k)-quasi-*-paranormal if ‖T1+n(Tkx)‖1/(1+n)Tkx1/(1+n)≥‖T*(Tkx)‖ for all xH, where n, k are nonnegative integers. This class of operators has many interesting properties and contains the classes of n-*-paranormal operators and quasi-*-paranormal operators. The aim of this note is to show that every Riesz idempotent Eλ with respect to a non-zero isolated spectral point λ of an (n)-quasi-*-paranormal operator T is self-adjoint and satisfies ranEλ=ker(T-λ)=ker(T-λ)*.

Key words: *-class A operator, *-paranormal operator, Riesz idempotent

中图分类号: 

  • 47A10