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Similarity invariant semigroups generated by non-Fredholm operators

Published online by Cambridge University Press:  17 April 2009

Iztok Kavkler
Iztok Kavkler
Affiliation:
Department of Mathematics, University of Ljubljana, Jadranska 19, 1000 Ljubljana, Slovenia, e-mail: iztok.kavkler@fmf.uni-lj.si
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Let A ∈ B(H) be a bounded non-compact operator that is not semi-Fredholm. The similarity invariant semigroup generated by A is shown to consist of all operators that are not semi-Fredholm and satisfy obvious inequalities for the nullity and co-nullity.

Type
Research Article
Information
Bulletin of the Australian Mathematical Society , Volume 72 , Issue 3 , December 2005 , pp. 407 - 421
Copyright
Copyright © Australian Mathematical Society 2005

References

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