Sur la conorme essentielle
Mbekhta, Mostafa ; Paul, Rodolphe
Studia Mathematica, Tome 119 (1996), p. 243-252 / Harvested from The Polish Digital Mathematics Library
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Pour un opérateur T borné sur un espace de Hilbert dans lui-même, nous montrons que γ(π(T))=supγ(T+K):Kopérateurcompact, où γ est la conorme (the reduced minimum modulus) et π(T) est la classe de T dans l’algèbre de Calkin. Nous montrons aussi que ce supremum est atteint. D’autre part, nous montrons que les opérateurs semi-Fredholm caractérisent les points de continuité de l’application T → γ (π(T)).

Publié le : 1996-01-01
EUDML-ID : urn:eudml:doc:216254 
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Mbekhta, Mostafa; Paul, Rodolphe. Sur la conorme essentielle. Studia Mathematica, Tome 119 (1996) pp. 243-252. http://gdmltest.u-ga.fr/item/bwmeta1.element.bwnjournal-article-smv117i3p243bwm/

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