Abstract
In this paper, we consider the special case of the question raised by Halmos (see below). In particular, we show that if T k is p-hyponormal, then T is a subscalar operator of order 4k. As a corollary, we obtain that if T k is p-hyponormal and σ(T) has nonempty interior in the plane, then T has a nontrivial invariant subspace.
| Original language | English |
|---|---|
| Pages (from-to) | 173-187 |
| Number of pages | 15 |
| Journal | Integral Equations and Operator Theory |
| Volume | 59 |
| Issue number | 2 |
| DOIs | |
| State | Published - Oct 2007 |
Bibliographical note
Funding Information:The work was supported by the Korea Research Foundation Grant funded by the Korean Government(MOEHRD, Basic Research Promotion Fund) (KRF-2006-312-C00461).
Keywords
- Invariant subspace
- P-hyponormality
- Subscalarity
- The property (β)