Bull. Austral. Math. Soc. 72(3) pp.407--421, 2005.

Similarity invariant semigroups generated by non-Fredholm operators

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Abstract

Let A B() 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.

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