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Perturbations by operators converging compactly to zero

Published online by Cambridge University Press:  24 October 2008

Eric Martens
Eric Martens
Affiliation:
University of Stellenbosch, South Africa
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Abstract

This paper considers perturbations in locally convex spaces of semi Fredholm operators T by a sequence of operators {Kn} converging compactly to zero in a sense extending that from (2). It is shown that, under suitable conditions, α(T + Kn) ≤ α(T), β(T + Kn) ≤ β;(T) and κ(T + Kn) = κ(T) for large n.

Type
Research Article
Information
Mathematical Proceedings of the Cambridge Philosophical Society , Volume 81 , Issue 3 , May 1977 , pp. 387 - 391
Copyright
Copyright © Cambridge Philosophical Society 1977

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References

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