On the B-discrete spectrum

Mohammed Berkani

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arXiv · 1606.03712

On the B-discrete spectrum

Mohammed Berkani

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Abstract

In this paper, we introduce the B-discrete spectrum of an unbounded closed operator and we prove that a closed operator has a purely B-discrete spectrum if and only if it has a meromorphic resolvent. After that, we study the stability of the B-discrete spectrum under several type of perturbations and we establish that two closed invertible linear operators having quasisimilar totally paranormal inverses have equal spectra and B-discrete spectra.

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BibTeX RIS

Mohammed Berkani. 2016-06-12. On the B-discrete spectrum. https://arxiv.org/abs/1606.03712

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