On the Harmonic characterization of domains via mean value formulas

Authors

  • Giovanni Cupini University of Bologna, Italy
  • Ermanno Lanconelli University of Bologna, Italy

Abstract

The Euclidean ball have the following harmonic characterization, via Gauss-mean value property: Let D be an open set with finite Lebesgue measure and let x0 be a point of D. If 

19691.png
for every nonnegative harmonic function u in D, then D is a Euclidean ball centered at x0. On the other hand, on every sufficiently smooth domain D and for every point x0 in there exist Radon measures μ such that
15abstract2.jpg
for every nonnegative harmonic function u in D. In this paper we give sufficient conditions so that this last mean value property characterizes the domain D.

Downloads

Published

2019-12-24

Issue

Section

Articoli