On completely hyperexpansive operators

Author:
Ameer Athavale

Journal:
Proc. Amer. Math. Soc. **124** (1996), 3745-3752

MSC (1991):
Primary 47B20; Secondary 47B39

DOI:
https://doi.org/10.1090/S0002-9939-96-03609-X

MathSciNet review:
1353373

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Abstract | References | Similar Articles | Additional Information

Abstract: We introduce and discuss a class of operators, to be referred to as the class of completely hyperexpansive operators, which is in some sense antithetical to the class of contractive subnormals. The new class is intimately related to the theory of negative definite functions on abelian semigroups. The known interplay between positive and negative definite functions from the theory of harmonic analysis on semigroups can be exploited to reveal some interesting connections between subnormals and completely hyperexpansive operators.

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Additional Information

**Ameer Athavale**

Affiliation:
Department of Mathematics, University of Pune, Pune - 411007, India

Email:
athavale@math.unipune.ernet.in

DOI:
https://doi.org/10.1090/S0002-9939-96-03609-X

Keywords:
Positive definite,
negative definite,
completely monotone,
completely alternating,
subnormal,
completely hyperexpansive

Received by editor(s):
May 17, 1995

Communicated by:
Palle E. T. Jorgensen

Article copyright:
© Copyright 1996
American Mathematical Society