English

Harmonic approximation by finite sums of moduli

Classical Analysis and ODEs 2021-08-20 v1

Abstract

Let h(Bd)h(B_d) denote the space of real-valued harmonic functions on the unit ball BdB_d of Rd\mathbb{R}^d, d2d\ge 2. Given a radial weight ww on BdB_d, consider the following problem: construct a finite family {f1,f2,,fJ}\{f_1, f_2, \dots, f_J\} in h(Bd)h(B_d) such that the sum f1+f2++fJ|f_1| + |f_2|+\dots + |f_J| is equivalent to ww. We solve the problem for weights ww with a doubling property. Moreover, if dd is even, then we characterize those ww for which the problem has a solution.

Keywords

Cite

@article{arxiv.1502.03775,
  title  = {Harmonic approximation by finite sums of moduli},
  author = {Evgueni Doubtsov},
  journal= {arXiv preprint arXiv:1502.03775},
  year   = {2021}
}

Comments

9 pages

R2 v1 2026-06-22T08:28:38.838Z