Operational quantities derived from the norm and generalized Fredholm theory
Gonzalez, Manuel ; Martinón, Antonio
Commentationes Mathematicae Universitatis Carolinae, Tome 32 (1991), p. 645-657 / Harvested from Czech Digital Mathematics Library
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We introduce and study some operational quantities associated to a space ideal $\Bbb A$. These quantities are used to define generalized semi-Fredholm operators associated to $\Bbb A$, and the corresponding perturbation classes which extend the strictly singular and strictly cosingular operators, and we study the generalized Fredholm theory obtained in this way. Finally we present some examples and show that the classes of generalized semi-Fredholm operators are non-trivial for several classical space ideals.

Publié le : 1991-01-01
Classification:  46B28,  47A30,  47A53,  47B10 
@article{118444,
     author = {Manuel Gonzalez and Antonio Martin\'on},
     title = {Operational quantities derived from the norm and generalized Fredholm theory},
     journal = {Commentationes Mathematicae Universitatis Carolinae},
     volume = {32},
     year = {1991},
     pages = {645-657},
     zbl = {0762.47005},
     mrnumber = {1159811},
     language = {en},
     url = {http://dml.mathdoc.fr/item/118444}
}

Gonzalez, Manuel; Martinón, Antonio. Operational quantities derived from the norm and generalized Fredholm theory. Commentationes Mathematicae Universitatis Carolinae, Tome 32 (1991) pp. 645-657. http://gdmltest.u-ga.fr/item/118444/

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