Journal of Inequalities and Applications
Volume 2006 (2006), Article ID 47481, 7 pages
doi:10.1155/JIA/2006/47481
The Fuglede-Putnam theorem for (p,k)-quasihyponormal operators
Department of Mathematics, Seoul National University, Seoul 151-747, Korea
Received 8 September 2004; Accepted 19 September 2004
Copyright © 2006 In Hyoun Kim. 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.
Abstract
We show that if T∈ℬ(ℋ) is a (p,k)-quasihyponormal operator and S∗∈ℬ(𝒦) is a p-hyponormal operator, and if TX=XS, where X:𝒦→ℋ is a quasiaffinity (i.e., a one-one map having dense range), then T is a normal and moreover T is unitarily equivalent to S.