## Annals of Functional Analysis

### Weyl type theorems for algebraically Quasi-$\mathcal{HNP}$ operators

#### Abstract

In this paper, by introducing the class of quasi hereditarily normaloid polaroid operators, we obtain a theoretical and general framework from which Weyl type theorems may be promptly established for many of these classes of operators. This framework also entails Weyl type theorems for perturbations $f(T + A)$, where $A$ is algebraic and commutes with $T,$ and $f$ is an analytic function, defined on an open neighborhood of the spectrum of $T +A$, such that $f$ is non constant on each of the components of its domain.

#### Article information

Source
Ann. Funct. Anal., Volume 6, Number 3 (2015), 262-274.

Dates
First available in Project Euclid: 17 April 2015

https://projecteuclid.org/euclid.afa/1429286045

Digital Object Identifier
doi:10.15352/afa/06-3-19

Mathematical Reviews number (MathSciNet)
MR3336918

Zentralblatt MATH identifier
1314.47012

#### Citation

Rashid, M. H. M.; Prasad, T. Weyl type theorems for algebraically Quasi-$\mathcal{HNP}$ operators. Ann. Funct. Anal. 6 (2015), no. 3, 262--274. doi:10.15352/afa/06-3-19. https://projecteuclid.org/euclid.afa/1429286045

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