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A characterization of Banach-star-algebras by numerical range

Published online by Cambridge University Press:  17 April 2009

Brailey Sims
Brailey Sims
Affiliation:
University of Newcastle, Newcastle, New South Wales.
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Abstract

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It is known that in a B*-algebra every self-adjoint element is hermitian. We give an elementary proof that this condition characterizes B*-algetras among Banach*-algebras.

Type
Research Article
Information
Bulletin of the Australian Mathematical Society , Volume 4 , Issue 2 , April 1971 , pp. 193 - 200
Copyright
Copyright © Australian Mathematical Society 1971

References

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