A note on the Liouville theorem of fully nonlinear elliptic equations
Dongsheng Li, Lichun Liang
TL;DR
The paper addresses the Liouville-type asymptotics for fully nonlinear elliptic equations $F(D^2u)=0$ in exterior domains, aiming to characterize solutions with at most quadratic growth without assuming $F$ is $C^2$ or restricting the dimension. It introduces a novel method that uses Evans-Krylov theory, barrier arguments, and Kelvin transformations to derive a sharp asymptotic expansion $u(x)=\frac{1}{2}x^{T}Ax+b\cdot x+d\,\Gamma(x)+c+\frac{e\cdot x}{|x^{T}(DF(A))^{-1}x|^{n/2}}+O(|x|^{1-n-\alpha})$ with a dimension-dependent correction $\Gamma(x)$. The result identifies the asymptotic quadratic form $A$, linear term $b$, and a Kelvin-type correction with coefficient $e$, together with logarithmic or power-like decay terms, and it holds under $F\in C^{1,2/n}$, convex, and uniformly elliptic, for viscosity solutions with quadratic growth. This advances the understanding of exterior-domain behavior for degenerate and fully nonlinear elliptic equations and extends prior works by removing reliance on higher regularity of $F$ and specific dimensional constraints.
Abstract
In this paper, a new method is presented to investigate the asymptotic behavior of solutions to the fully nonlinear uniformly elliptic equation $F(D^2u)=0$ in exterior domains. This method does not depend on the $C^2$ regularity of $F$ and the dimension $n$.
