On inessential and improjective operators.

• Autorzy: Pietro Aiena , Manuel González
• Języki publikacji: EN

Abstrakty

EN

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.

Słowa kluczowe

EN

inessential operator; improjective operator; Fredholm theory

Kategorie tematyczne

• 47A53: (Semi-) Fredholm operators; index theories

• Wydawca: Institute of Mathematics Polish Academy of Sciences
• Czasopismo: Studia Mathematica
• Rocznik: 1998
• Tom: 131
• Numer: 3
• Strony: 271-287

Daty

wydano

1998

otrzymano

1997-09-30

poprawiono

1998-05-22

Twórcy

autor

Pietro Aiena

• Dipartimento di Matematica ed Applicazioni, Facoltà di Ingegneria, Università di Palermo, Viale delle Scienze, I-90128 Palermo, Italy

autor

Manuel González

• Departamento de Matemáticas, Facultad de Ciencias, Universidad de Cantabria, E-39071 Santander, Spain

Bibliografia

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