Abstract
We give an improvement of the result that if $hP\ge0$ on $\R^n$, where $h$ is a harmonic function and $P$ a non-trivial harmonic polynomial, then $h$ is proportional to $P$.
Citation
D. H. Armitage. "The Determination of a Harmonic Function by Its Sign." Real Anal. Exchange 33 (2) 275 - 278, 2007/2008.
Information
Published: 2007/2008
First available in Project Euclid: 18 December 2008
zbMATH: 1165.31001
MathSciNet: MR2458244
Subjects:
Primary:
31A05
Keywords:
Harmonic function
,
Liouville theorem
Rights: Copyright © 2007 Michigan State University Press
