Open Access

Spectrum of Class Operators

Journal of Inequalities and Applications20072007:027195

DOI: 10.1155/2007/27195

Received: 23 November 2006

Accepted: 16 May 2007

Published: 18 June 2007


This paper discusses some spectral properties of class operators for , , , and . It is shown that if is a class operator, then the Riesz idempotent of with respect to each nonzero isolated point spectrum is selfadjoint and . Afterwards, we prove that every class operator has SVEP and property , and Weyl's theorem holds for when .


Authors’ Affiliations

LMIB and Department of Mathematics, Beihang University
Dedicated to Professor Daoxing Xia on his 77th birthday with respect and affection


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© J. Yuan and Z. Gao. 2007

This article is published under license to BioMed Central Ltd. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.