Computing the Fredholm index of Toeplitz operators with continuous symbols

Authors:
Nathan S. Feldman and Paul McGuire

Journal:
Proc. Amer. Math. Soc. **133** (2005), 1357-1364

MSC (2000):
Primary 47B20, 47A53; Secondary 47A10

Published electronically:
October 15, 2004

MathSciNet review:
2111959

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Abstract | References | Similar Articles | Additional Information

Abstract: We show how to compute the Fredholm index of a Toeplitz operator with a continuous symbol constructed from any subnormal operator with compact self-commutator. We also show that the essential spectral pictures of such Toeplitz operators can be prescribed arbitrarily.

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Additional Information

**Nathan S. Feldman**

Affiliation:
Department of Mathematics, Washington and Lee University, Lexington, Virginia 24450

Email:
feldmanN@wlu.edu

**Paul McGuire**

Affiliation:
Department of Mathematics, Bucknell University, Lewisburg, Pennsylvania 17837

Email:
pmcguire@bucknell.edu

DOI:
http://dx.doi.org/10.1090/S0002-9939-04-07642-7

Keywords:
Subnormal operator,
essentially normal operator,
Fredholm operator,
Fredholm index

Received by editor(s):
October 6, 2003

Received by editor(s) in revised form:
December 23, 2003

Published electronically:
October 15, 2004

Communicated by:
Joseph A. Ball

Article copyright:
© Copyright 2004
American Mathematical Society

The copyright for this article reverts to public domain 28 years after publication.