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arXiv · 0810.3273

Finite Gap Jacobi Matrices, I. The Isospectral Torus

Jacob S. Christiansen·Barry Simon·Maxim Zinchenko
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Abstract

Let $\frak{e}\subset\mathbb{R}$ be a finite union of disjoint closed intervals. In the study of OPRL with measures whose essential support is $\frak{e}$, a fundamental role is played by the isospectral torus. In this paper, we use a covering map formalism to define and study this isospectral torus. Our goal is to make a coherent presentation of properties and bounds for this special class as a tool for ourselves and others to study perturbations. One important result is the expression of Jost functions for the torus in terms of theta functions.

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BibTeXRIS

Jacob S. Christiansen, Barry Simon, Maxim Zinchenko. 2008-10-17. Finite Gap Jacobi Matrices, I. The Isospectral Torus. https://arxiv.org/abs/0810.3273

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