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

In Hyoun Kim

 Department of Mathematics, Seoul National University, Seoul 151-747, Korea
Received 8 September 2004; Accepted 19 September 2004

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.