Nontrivial solution of a semilinear schrödinger equation
Christophe Troestler, Michel Willem · Communications in Partial Differential Equations · 1996
This paper deals with strongly indefinite functionals whose gradients are Fredholm operators of index 0 and map weakly convergent sequences to weakly convergent sequences. We show how these results apply to a ZN—invariant semilinear Schrödinger equation on RN.