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ArticleOriginal scientific text

Title

On inessential and improjective operators.

Authors 1, 2

Affiliations

  1. Dipartimento di Matematica ed Applicazioni, Facoltà di Ingegneria, Università di Palermo, Viale delle Scienze, I-90128 Palermo, Italy
  2. Departamento de Matemáticas, Facultad de Ciencias, Universidad de Cantabria, E-39071 Santander, Spain

Abstract

We give several characterizations of the improjective operators, introduced by Tarafdar, and we characterize the inessential operators among the improjective operators. It is an interesting problem whether both classes of operators coincide in general. A positive answer would provide, for example, an intrinsic characterization of the inessential operators. We give several equivalent formulations of this problem and we show that the inessential operators acting between certain pairs of Banach spaces coincide with the improjective operators.

Keywords

ENG
inessential operator, improjective operator, Fredholm theory

Bibliography

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Studia Mathematica
1998/131/3
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Pages:
271-287
Main language of publication
English
Received
1997-09-30
Accepted
1998-05-22
Published
1998
Exact and natural sciences