On the critical points of solutions of Robin boundary problems

Fabio De Regibus, Massimo Grossi

In this paper we prove the uniqueness of the critical point for stable solutions of the Robin problem \[ \begin{cases} -Δu=f(u)&\text{in }Ω\\ u>0&\text{in }Ω\\ \partial_νu+βu=0&\te…