Open Access

The Fuglede-Putnam theorem for -quasihyponormal operators

Journal of Inequalities and Applications20062006:47481

https://doi.org/10.1155/JIA/2006/47481

Received: 8 September 2004

Accepted: 19 September 2004

Published: 22 January 2006

Abstract

We show that if is a -quasihyponormal operator and is a -hyponormal operator, and if , where is a quasiaffinity (i.e., a one-one map having dense range), then is a normal and moreover is unitarily equivalent to .

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Authors’ Affiliations

(1)
Department of Mathematics, Seoul National University

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Copyright

© Hindawi Publishing Corporation. 2006

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.