摘要
In this note, we study the Liouville equation Delta u = -e(u) on a graph G satisfying a certain isoperimetric inequality. Following the idea of W. Ding, we prove that there exists a uniform lower bound for the energy, Sigma(G)e(u) , of any solution u to the equation. In particular, for the 2-dimensional lattice graph Z(2) , the lower bound is given by 4.