Operational quantities characterizing semi-Fredholm operators

• Autorzy: Manuel González , Antonio Martinón
• Języki publikacji: EN

Abstrakty

EN

Several operational quantities have appeared in the literature characterizing upper semi-Fredholm operators. Here we show that these quantities can be divided into three classes, in such a way that two of them are equivalent if they belong to the same class, and are comparable and not equivalent if they belong to different classes. Moreover, we give a similar classification for operational quantities characterizing lower semi-Fredholm operators.

Słowa kluczowe

EN

operational quantity; semi-Fredholm operator

Kategorie tematyczne

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

• Wydawca: Institute of Mathematics Polish Academy of Sciences
• Czasopismo: Studia Mathematica
• Rocznik: 1995
• Tom: 114
• Numer: 1
• Strony: 13-27

Daty

wydano

1995

otrzymano

1993-07-16

poprawiono

1995-01-05

Twórcy

autor

Manuel González

• Departamento de Matemáticas, Universidad de Cantabria, 39071 Santander, Spain

autor

Antonio Martinón

• Departamento de Análisis Matemático, Universidad de La Laguna, 38271 La Laguna (Tenerife), Spain

Bibliografia

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