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Quantities related to upper and lower semi-Fredholm type linear relations

Published online by Cambridge University Press:  17 April 2009

Teresa Alvarez ,
Ronald Cross  and
Diane Wilcox
Teresa Alvarez
Affiliation:
Department of Mathematics, University of Oviedo, 33007 Oviedo, Spain e-mail: seco@pinon.ccu.uniovi.es
Ronald Cross
Affiliation:
Department of Mathematics and Applied Mathematics, University of Cape Town, Rondebosch, 7700, South Africa e-mail: cross@maths.uct.ac.za
Diane Wilcox
Affiliation:
Department of Mathematics and Applied Mathematics, University of Cape Town, Rondebosch 7700, South Africa e-mail: diane@maths.uct.ac.za
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Certain norm related functions of linear operators are considered in the very general setting of linear relations in normed spaces. These are shown to be closely related to the theory of strictly singular, strictly cosingular, F+ and F− linear relations. Applications to perturbation theory follow.

Type
Research Article
Information
Bulletin of the Australian Mathematical Society , Volume 66 , Issue 2 , October 2002 , pp. 275 - 289
Copyright
Copyright © Australian Mathematical Society 2002

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