Uniqueness of reflectionless Jacobi matrices and the Denisov-Rakhmanov Theorem

Christian Remling

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arXiv · 1006.2780

Uniqueness of reflectionless Jacobi matrices and the Denisov-Rakhmanov Theorem

Christian Remling

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Abstract

If a Jacobi matrix $J$ is reflectionless on $(-2,2)$ and has a single $a_{n_0}$ equal to 1, then $J$ is the free Jacobi matrix $a_n\equiv 1$, $b_n\equiv 0$. I'll discuss this result and its generalization to arbitrary sets and present several applications, including the following: if a Jacobi matrix has some portion of its $a_n$'s close to 1, then one assumption in the Denisov-Rakhmanov Theorem can be dropped.

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BibTeX RIS

Christian Remling. 2010-06-14. Uniqueness of reflectionless Jacobi matrices and the Denisov-Rakhmanov Theorem. https://arxiv.org/abs/1006.2780

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