Nonradial solutions of nonlinear scalar field equations

Jarosław Mederski

Published 2017-11-15Version 1

We prove new results concerning the nonlinear scalar field equation \begin{equation*} \left\{ \begin{array}{ll} -\Delta u = g(u)&\quad \hbox{in }\mathbb{R}^N,\; N\geq 3,\\ u\in H^1(\mathbb{R}^N)& \end{array} \right. \end{equation*} with a nonlinearity $g$ satisfying the general assumptions due to Berestycki and Lions. In particular, we find at least one nonradial solution for any $N\geq 4$ minimizing the energy functional on the topological Pohozaev constraint. If in addition $N\neq 5$, then there are infinitely many nonradial solutions. The results give a partial answer to an open question posed by Berestycki and Lions in [5,6]. Moreover, we build a critical point theory on a topological manifold, which enables us to solve the above equation as well as to treat new elliptic problems.