Pointwise Remez inequality
Classical Analysis and ODEs
2020-07-06 v1
Abstract
The standard well-known Remez inequality gives an upper estimate of the values of polynomials on if they are bounded by on a subset of of fixed Lebesgue measure. The extremal solution is given by the rescaled Chebyshev polynomials for one interval. Andrievskii asked about the maximal value of polynomials at a fixed point, if they are again bounded on a set of fixed size. We show that the extremal polynomials are either Chebyshev (one interval) or Akhiezer polynomials (two intervals) and prove Totik-Widom bounds for the extremal value, thereby providing a complete asymptotic solution to the Andrievskii problem.
Keywords
Cite
@article{arxiv.2007.01607,
title = {Pointwise Remez inequality},
author = {B. Eichinger and P. Yuditskii},
journal= {arXiv preprint arXiv:2007.01607},
year = {2020}
}