Noncontinuity of spectrum for the adjoint

of an operator

Author:
Laura Burlando

Journal:
Proc. Amer. Math. Soc. **128** (2000), 173-182

MSC (1991):
Primary 47A10, 47C05

DOI:
https://doi.org/10.1090/S0002-9939-99-05044-3

Published electronically:
June 17, 1999

MathSciNet review:
1625705

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Abstract | References | Similar Articles | Additional Information

Abstract: This paper deals with the connection between continuity of spectrum at an element of the Banach algebra of all bounded linear operators on a Banach space and at the adjoint of . In particular, we show that, if is not reflexive, the spectrum function may be continuous at and discontinuous at .

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Additional Information

**Laura Burlando**

Affiliation:
Dipartimento di Matematica, Università di Genova, Via Dodecaneso 35, 16146 Genova, Italy

Email:
burlando@dima.unige.it

DOI:
https://doi.org/10.1090/S0002-9939-99-05044-3

Keywords:
Continuity of spectrum,
adjoint operators in Banach spaces

Received by editor(s):
March 12, 1998

Published electronically:
June 17, 1999

Communicated by:
David R. Larson

Article copyright:
© Copyright 1999
American Mathematical Society