6533b85bfe1ef96bd12bb413

RESEARCH PRODUCT

Weyl's theorem for perturbations of paranormal operators

Pietro AienaJesús R. Guillén

subject

Unbounded operatorPure mathematicsApplied MathematicsGeneral MathematicsHilbert spaceBanach spaceMathematics::Spectral TheoryCompact operatorOperator spaceBounded operatorsymbols.namesakesymbolsWeyl transformationContraction (operator theory)Mathematics

description

A bounded linear operator T ∈ L(X) on a Banach space X is said to satisfy "Weyl's theorem" if the complement in the spectrum of the Weyl spectrum is the set of all isolated points of the spectrum which are eigenvalues of finite multiplicity. In this paper we show that if T is a paranormal operator on a Hilbert space, then T + K satisfies Weyl's theorem for every algebraic operator K which commutes with T.

https://doi.org/10.1090/s0002-9939-07-08582-6