English

Integration of monomials over the unit spere and unit ball in $R^n$

Classical Analysis and ODEs 2025-01-16 v1

Abstract

We compute the integral of monomials of the form x2βx^{2\beta} over the unit sphere and the unit ball in RnR^n where β=(β1,...,βn)\beta = (\beta_1,...,\beta_n) is a multi-index with real components βk>1/2\beta_k > -1/2, 1kn1 \le k \le n, and discuss their asymptotic behavior as some, or all, βk\beta_k \to\infty. This allows for the evaluation of integrals involving circular and hyperbolic trigonometric functions over the unit sphere and the unit ball in Rn R^n. We also consider the Fourier transform of monomials xαx^\alpha restricted to the unit sphere in RnR^n, where the multi-indices α\alpha have integer components, and discuss their behaviour at the origin.

Keywords

Cite

@article{arxiv.2501.08493,
  title  = {Integration of monomials over the unit spere and unit ball in $R^n$},
  author = {Calixto P. Calderon and Alberto Torchinsky},
  journal= {arXiv preprint arXiv:2501.08493},
  year   = {2025}
}