Published May 2023 | Version Published
Journal Article

Asymptotics of Chebyshev polynomials, V. residual polynomials

  • 1. ROR icon Lund University
  • 2. ROR icon California Institute of Technology
  • 3. ROR icon University of New Mexico

Abstract

We study residual polynomials, R^((e))_(x₀,n), e ⊂ , x₀ ∈ ∖e, which are the degree at most n polynomials with R(x₀) = 1 that minimize the sup sup norm on e. New are upper bounds on their norms (that are optimal in some cases) and Szegő–Widom asymptotics under fairly general circumstances. We also discuss several illuminating examples and some results in the complex case such as root asymptotics, a universal lower bound, and a new characterization of sets saturating this lower bound.

Copyright and License

© The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature 2023.

Acknowledgement

We would like to thank M. Ismail, D. Lubinsky, and K. Schiefermayr for useful comments.

Funding

J. S. Christiansen: Research supported by VR Grant 2018-03500 from the Swedish Research Council.
B. Simon: Research supported by NSF Grant DMS-1665526.
M. Zinchenko: Research supported in part by Simons Foundation Grant CGM-581256.

Additional details

Related works

Is new version of
Discussion Paper: arXiv:2008.09669 (arXiv)

Funding

Swedish Research Council
2018-03500
NSF
DMS-1665526
Simons Foundation
CGM-581256

Dates

Submitted
2020-09-18
Accepted
2021-07-29
Available
2021-10-18
Published