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Title

Axiomatic theory of spectrum III: semiregularities

Authors 1

Affiliations

  1. Institute of Mathematics AV ČR, Žitná 25, 115 67 Praha 1, Czech Republic

Abstract

We introduce and study the notions of upper and lower semiregularities in Banach algebras. These notions generalize the previously studied notion of regularity - a class is a regularity if and only if it is both upper and lower semiregularity. Each semiregularity defines in a natural way a spectrum which satisfies a one-way spectral mapping property (the spectrum defined by a regularity satisfies the both-ways spectral mapping property).

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Studia Mathematica
2000/142/2
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Pages:
159-169
Main language of publication
English
Received
1999-11-22
Published
2000
Exact and natural sciences