English

Approximation properties of the double Fourier sphere method

Numerical Analysis 2022-03-23 v1 Numerical Analysis Functional Analysis

Abstract

We investigate analytic properties of the double Fourier sphere (DFS) method, which transforms a function defined on the two-dimensional sphere to a function defined on the two-dimensional torus. Then the resulting function can be written as a Fourier series yielding an approximation of the original function. We show that the DFS method preserves smoothness: it continuously maps spherical H\"older spaces into the respective spaces on the torus, but it does not preserve spherical Sobolev spaces in the same manner. Furthermore, we prove sufficient conditions for the absolute convergence of the resulting series expansion on the sphere as well as results on the speed of convergence.

Keywords

Cite

@article{arxiv.2108.05662,
  title  = {Approximation properties of the double Fourier sphere method},
  author = {Sophie Mildenberger and Michael Quellmalz},
  journal= {arXiv preprint arXiv:2108.05662},
  year   = {2022}
}
R2 v1 2026-06-24T05:03:37.642Z