[en] 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 $mathbb{Z}^N$-invariant semilinear Schrödinger equation on~$mathbb{R}^N$.
Research center :
CREMMI - Modélisation mathématique et informatique
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