Nonlinear boundary conditions for elliptic equations

Abstract

This work is devoted to the study of the elliptic equation $Delta u = f(x,u)$ in a bounded domain $Omegasubset mathbb{R}^n$ with a nonlinear boundary condition. We obtain various existence results applying coincidence degree theory and the method of upper and lower solutions.

Keywords

• Nonlinear elliptic problems
• nonlinear boundary conditions
• topological methods.