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arXiv · 0809.2255

The Nevai Condition

Jonathan Breuer·Yoram Last·Barry Simon
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Abstract

We study Nevai's condition that for orthogonal polynomials on the real line, $K_n(x,x_0)^2 K_n(x_0,x_0)^{-1} dρ(x)\toδ_{x_0}$ where $K_n$ is the CD kernel. We prove that it holds for the Nevai class of a finite gap set uniformly on the spectrum and we provide an example of a regular measure on $[-2,2]$ where it fails on an interval.

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Jonathan Breuer, Yoram Last, Barry Simon. 2008-09-12. The Nevai Condition. https://arxiv.org/abs/0809.2255

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