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arXiv · 1306.0041

Gohberg lemma, compactness, and essential spectrum of operators on compact Lie groups

Aparajita Dasgupta·Michael Ruzhansky
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Abstract

In this paper we prove a version of the Gohberg lemma on compact Lie groups giving an estimate from below for the distance from a given operator to the set of compact operators on compact Lie groups. As a consequence, we prove several results on bounds for the essential spectrum and a criterion for an operator to be compact. The conditions are given in terms of the matrix-valued symbols of operators.

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Aparajita Dasgupta, Michael Ruzhansky. 2013-05-31. Gohberg lemma, compactness, and essential spectrum of operators on compact Lie groups. https://doi.org/10.1007/s11854-016-0005-0

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