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ArticleOriginal scientific text

Title

On the semi-Browder spectrum

Authors 1, 1, 2

Affiliations

  1. Institute of Mathematics AV ČR, Žitná 25, 11567 Praha 1, Czech Republic
  2. Department of Mathematics, Faculty of Philosophy, University of Niš, Ćirila and Metodija 2, 18000 Niš, Yugoslavia - Serbia

Abstract

An operator in a Banach space is called upper (lower) semi-Browder if it is upper (lower) semi-Fredholm and has a finite ascent (descent). We extend this notion to n-tuples of commuting operators and show that this notion defines a joint spectrum. Further we study relations between semi-Browder and (essentially) semiregular operators.

Bibliography

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Studia Mathematica
1997/123/1
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Pages:
1-13
Main language of publication
English
Received
1995-08-07
Accepted
1996-08-09
Published
1997
Exact and natural sciences