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ArticleOriginal scientific text

Title

Adjoint characterisations of unbounded weakly compact, weakly completely continuous and unconditionally converging operators

Authors 1, 2, 2

Affiliations

  1. Department of Mathematics, University of Oviedo, 33007 Oviedo, Spain
  2. Department of Mathematics, University of Cape Town, 7700 Rondebosch, South Africa

Abstract

Characterisations are obtained for the following classes of unbounded linear operators between normed spaces: weakly compact, weakly completely continuous, and unconditionally converging operators. Examples of closed unbounded operators belonging to these classes are exhibited. A sufficient condition is obtained for the weak compactness of T' to imply that of T.

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Studia Mathematica
1995/113/3
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Pages:
283-298
Main language of publication
English
Received
1994-11-08
Accepted
1994-12-08
Published
1995
Exact and natural sciences