On the essential spectrum of the sum of self-adjoint operators and the closedness of the sum of operator ranges

Ivan S. Feshchenko

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arXiv · 1212.2954

On the essential spectrum of the sum of self-adjoint operators and the closedness of the sum of operator ranges

Ivan S. Feshchenko

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Abstract

We get a criterion for 0 to be in the essential spectrum of a sum of self-adjoint operators whose pairwise products are compact. Using this result, we obtain necessary and sufficient conditions for the sum of ranges of such operators to be closed.

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BibTeX RIS

Ivan S. Feshchenko. 2013-06-01. On the essential spectrum of the sum of self-adjoint operators and the closedness of the sum of operator ranges. https://arxiv.org/abs/1212.2954

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