English

Covering and separation of Chebyshev points for non-integrable Riesz potentials

Classical Analysis and ODEs 2017-03-02 v1

Abstract

For Riesz ss-potentials K(x,y)=xysK(x,y)=|x-y|^{-s}, s>0s>0, we investigate separation and covering properties of NN-point configurations ωN={x1,,xN}\omega^*_N=\{x_1, \ldots, x_N\} on a dd-dimensional compact set ARA\subset \mathbb{R}^\ell for which the minimum of j=1NK(x,xj)\sum_{j=1}^N K(x, x_j) is maximal. Such configurations are called NN-point optimal Riesz ss-polarization (or Chebyshev) configurations. For a large class of dd-dimensional sets AA we show that for s>ds>d the configurations ωN\omega^*_N have the optimal order of covering. Furthermore, for these sets we investigate the asymptotics as NN\to \infty of the best covering constant. For these purposes we compare best-covering configurations with optimal Riesz ss-polarization configurations and determine the ss-th root asymptotic behavior (as ss\to \infty) of the maximal ss-polarization constants. In addition, we introduce the notion of "weak separation" for point configurations and prove this property for optimal Riesz ss-polarization configurations on AA for s>dim(A)s>\text{dim}(A), and for d1s<dd-1\leqslant s < d on the sphere Sd\mathbb{S}^d.

Keywords

Cite

@article{arxiv.1703.00106,
  title  = {Covering and separation of Chebyshev points for non-integrable Riesz potentials},
  author = {Alexander Reznikov and Edward B. Saff and Alexander Volberg},
  journal= {arXiv preprint arXiv:1703.00106},
  year   = {2017}
}