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arXiv · 2006.07959

About essential spectra of unbounded Jacobi matrices

Grzegorz Świderski·Bartosz Trojan
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Abstract

We study spectral properties of unbounded Jacobi matrices with periodically modulated or blended entries. Our approach is based on uniform asymptotic analysis of generalized eigenvectors. We determine when the studied operators are self-adjoint. We identify regions where the point spectrum has no accumulation points. This allows us to completely describe the essential spectrum of these operators.

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BibTeXRIS

Grzegorz Świderski, Bartosz Trojan. 2020-06-14. About essential spectra of unbounded Jacobi matrices. https://doi.org/10.1016/j.jat.2022.105746

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