Articles

A NOTE ON n-PERINORMAL OPERATORS

  • ZUO Hong-Liang ,
  • ZUO Fei
Expand
  • College of Mathematics and Information Science, Henan Normal University, Xinxiang 453007, China

Received date: 2012-08-30

  Revised date: 2013-01-22

  Online published: 2014-01-20

Supported by

This work is partially supported by NNSF (11226185, 11201126) and the Basic Science and Technological Frontier Project of Henan Province (132300410261).

Abstract

The study of operators satisfying σja(T) = σa(T) is of significant interest. Does σja(T) = σa(T) for n-perinormal operator T ∈B(H)? This question was raised by Mecheri and Braha [Oper. Matrices 6 (2012), 725–734]. In the note we construct a
counterexample to this question and obtain the following result: if T is a n-perinormal operator in B(H), then σja(T)\{0} = σa(T)\{0}. We also consider tensor product of n-perinormal operators.

Cite this article

ZUO Hong-Liang , ZUO Fei . A NOTE ON n-PERINORMAL OPERATORS[J]. Acta mathematica scientia, Series B, 2014 , 34(1) : 194 -198 . DOI: 10.1016/S0252-9602(13)60136-8

References

[1] Aluthge A, Wang D. The joint approximate point spectrum of an operator. Hokkaido Mathe J, 2002, 31: 187–197

[2] Aluthge A, Wang D. w-hyponormal operators II. Integr Equ Oper Theory, 2000, 37(3): 324–331

[3] Ando T. Operators with a norm condition. Acta Sci Math (Szeged), 1972, 33: 169–178

[4] Berberian S K. Approximate proper vectors. Proc Amer Math Soc, 1962, 13: 111–114

[5] Braha N L, Lohaj M, Marevci F, et al. Some properties of paranormal and hyponormal operators. Bull Math Anal Appl, 2009, 2: 23–35

[6] Chennappan N, Karthikeyan S. *-Paranormal composition operators. Indian J Pure Appl Math, 2000, 31(6): 591–601

[7] Ch¯o M, Yamazaki T. An operator transform from class A to the class of hyponormal operators and its application. Integr Equ Oper Theory, 2005, 53(4): 497–508

[8] Duggal B P. Tensor products of operators-strong stability and p-hyponormality. Glasgow Math J, 2000, 42(3): 371–381

[9] Fujii M, Izumino S, Nakamoto R. Classes of operators determined by the Heinz-Kato-Furuta inequality and the H¨older-McCarthy inequality. Nihonkai Math J, 1994, 5: 61–67

[10] Furuta T. Invitation to Linear Operators. London: Taylor & Francis, 2001

[11] Hou J C. On tensor products of operators. Acta Math Sin, 1993, 9(2): 195–202

[12] Mecheri S, Braha N L. Spectrum properties of n-perinormal operators. Oper Matrices, 2012, 6: 725–734

[13] Panayappan S, Jayanthi N, Sumathi D. Weyl’s theorem and tensor production for class Ak operators. Pure Math Sci, 2012, 1(1): 13–23

[14] Saitˆo T. Hyponormal Operators and Related Topics. Lect Notes Math, 247. Berlin: Springer-Verlag, 1971

[15] Stochel J. Seminormality of operators from their tensor products. Proc Amer Math Soc, 1996, 124(1): 135–140

[16] Tanahashi K. On log-hyponormal operators. Integr Equ Oper Theory, 1999, 34(3): 364–372

[17] Uchiyama A. Weyl’s theorem for class A operators. Math Inequal Appl, 2001, 4(1): 143–150

[18] Xia D. Spectral Theory of Hyponormal Operators. Basel: Birkhauser Verlag, 1983

[19] Wang Z, Wei J, Li L. Poincar´e series and an application to Weyl algebras. Acta Math Sci, 2011, 31B(2): 459–467

Outlines

/