A Structured Inverse Spectrum Problem For Infinite Graphs

Keivan Hassani Monfared; Ehssan Khanmohammadi

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arXiv · 1512.05834

A Structured Inverse Spectrum Problem For Infinite Graphs

Keivan Hassani Monfared·Ehssan Khanmohammadi

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Abstract

It is shown that for a given infinite graph $G$ on countably many vertices, and a compact, infinite set of real numbers $Λ$ there is a real symmetric matrix $A$ whose graph is $G$ and its spectrum is $Λ$. Moreover, the set of limit points of $Λ$ equals the essential spectrum of $A$, and the isolated points of $Λ$ are eigenvalues of $A$ with multiplicity one. It is also shown that any two such matrices constructed by our method are approximately unitarily equivalent.

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BibTeX RIS

Keivan Hassani Monfared, Ehssan Khanmohammadi. 2016-10-05. A Structured Inverse Spectrum Problem For Infinite Graphs. https://arxiv.org/abs/1512.05834

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