Dual pair of eigenvalues in rank one singular nonsymmetric perturbations
Journal Title: Математичні Студії - Year 2017, Vol 48, Issue 2
Abstract
In the separable Hilbert space, we discuss the eigenvalue problem for a rank one singular nonselfadjoint perturbation of a selfadjoint operator A, by nonsymmetric potential (δ1≠δ2) in the form A~=A+α⟨⋅,δ1⟩δ2. We give the constructive description of such sort operator A~ which possess two new points in the point spectrum in case of weakly singular perturbations.
Authors and Affiliations
Tetyana Vdovenko, M. E. Dudkin
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