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Closure properties of the quasi-centre of a Banach algebra

Published online by Cambridge University Press:  24 October 2008

J. F. Rennison
J. F. Rennison
Affiliation:
Mathematical Institute, University of Kent, Canterbury, Kent CT2 7NF
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Extract

Throughout the paper, A will denote a unital Banach algebra with centre Z over the complex field ℂ. An element a of A is called quasi-central if, for some K ≥ 1,

The set of elements a satisfying (1) for a particular value of K will be denoted by Q(K) and Q = UK≥1Q(K) will be called the quasi-centre of A.

Type
Research Article
Information
Mathematical Proceedings of the Cambridge Philosophical Society , Volume 108 , Issue 2 , September 1990 , pp. 355 - 364
Copyright
Copyright © Cambridge Philosophical Society 1990

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References

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