k-Hyponormality and n-Contractivity for Agler-Type Shifts

Authors

Gregory Adams, Bucknell UniversityFollow
George Exner, Bucknell UniversityFollow

Publication Date

2014

Description

We consider k-hyponormality and n-contractivity (k, n = 1, 2, ...) as "weak subnormalities" for a Hilbert space operator. It is known that k-hyponormality implies 2k-contractivity; we produce some classes of weighted shifts including a parameter for which membership in a certain n-contractive class is equivalent to k-hyponormality. We consider as well some extensions of these results to operators arising as restrictions of these shifts, or from linear combinations of the Berger measures associated with the shifts.

Journal

Journal of Operator Theory

Volume

71

Issue

2

First Page

585

Last Page

600

Department

Mathematics

Link to Published Version

dx.doi.org/10.7900/jot.2012aug08.1965

DOI

10.7900/jot.2012aug08.1965

Recommended Citation

Adams, Gregory and Exner, George. "k-Hyponormality and n-Contractivity for Agler-Type Shifts." Journal of Operator Theory (2014) : 585-600.