-hyponormality of powers of weighted shifts via Schur products

Authors:
Raúl Curto and Sang Soo Park

Journal:
Proc. Amer. Math. Soc. **131** (2003), 2761-2769

MSC (1991):
Primary 47B37, 47B20; Secondary 47-04, 47A13

Published electronically:
November 13, 2002

MathSciNet review:
1974333

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Abstract | References | Similar Articles | Additional Information

Abstract: We characterize -hyponormality and quadratic hyponormality of powers of weighted shifts using Schur product techniques.

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Additional Information

**Raúl Curto**

Affiliation:
Department of Mathematics, The University of Iowa, Iowa City, Iowa 52242

Email:
curto@math.uiowa.edu

**Sang Soo Park**

Affiliation:
Department of Mathematics, Kyungpook National University, Deagu, Korea

Email:
pss4855@hanmail.net

DOI:
http://dx.doi.org/10.1090/S0002-9939-02-06805-3

Keywords:
$k$-hyponormality,
powers of weighted shifts,
Schur products

Received by editor(s):
October 5, 2001

Received by editor(s) in revised form:
March 27, 2002

Published electronically:
November 13, 2002

Additional Notes:
The research of the first author was partially supported by NSF grant DMS-9800931

The research of the second author was partially supported by KOSEF research project no. R01-2000-00003

Communicated by:
Joseph A. Ball

Article copyright:
© Copyright 2002
American Mathematical Society