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arXiv · 1304.5800

One-dimensional perturbations of unbounded selfadjoint operators with empty spectrum

Abstract

We study spectral properties of one-dimensional singular perturbations of an unbounded selfadjoint operator and give criteria for the possibility to remove the whole spectrum by a perturbation of this type. A counterpart of our results for the case of bounded operators provides a complete description of compact selfadjoint operators whose rank one perturbation is a Volterra operator.

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Anton D. Baranov, Dmitry V. Yakubovich. 2013-04-21. One-dimensional perturbations of unbounded selfadjoint operators with empty spectrum. https://arxiv.org/abs/1304.5800

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