Uniqueness, non-degeneracy, and exact multiplicity of positive solutions for superlinear elliptic problems

Guglielmo Feltrin, Christophe Troestler

In this paper, we focus our attention on the positive solutions to second-order nonlinear ordinary differential equations of the form $u^{\prime \prime }+q(t)g(u)=0$, where $q$ is a sign-changing…