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arXiv · 2003.04400

A simple proof of the optimal power in Liouville theorems

Salvador Villegas
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Abstract

Consider the equation div$(φ^2 \nabla σ)=0$ in $\mathbb{R}^N,$ where $φ>0$. It is well-known that if there exists $C>0$ such that $\int_{B_R}(φσ)^2 dx\leq CR^2$ for every $R\geq 1$ then $σ$ is necessarily constant. In this paper we prove that this result is not true if we replace $R^2$ by $R^k$ for $k>2$ in any dimension $N$. This question is related to a conjecture by De Giorgi.

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Salvador Villegas. 2020-10-09. A simple proof of the optimal power in Liouville theorems. https://arxiv.org/abs/2003.04400

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