hyponormality of powers of weighted shifts via Schur products
Authors:
Raúl Curto and Sang Soo Park
Journal:
Proc. Amer. Math. Soc. 131 (2003), 27612769
MSC (1991):
Primary 47B37, 47B20; Secondary 4704, 47A13
Published electronically:
November 13, 2002
MathSciNet review:
1974333
Fulltext PDF Free Access
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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 [CF1]
 R. Curto and L. Fialkow, Recursiveness, positivity, and truncated moment problems, Houston J. Math. 17(1991), 603635. MR 93a:47016
 [CF2]
 R. Curto and L. Fialkow, Recursively generated weighted shifts and the subnormal completion problem, Integral Equations Operator Theory 17(1993), 202246. MR 94h:47050
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 R. Curto, I.B. Jung and W.Y. Lee, Extension and extremality of recursively generated weighted shifts, Proc. Amer. Math. Soc. 130(2002), 565576. MR 2002i:47041
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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/S0002993902068053
PII:
S 00029939(02)068053
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 DMS9800931
The research of the second author was partially supported by KOSEF research project no. R01200000003
Communicated by:
Joseph A. Ball
Article copyright:
© Copyright 2002
American Mathematical Society
