## Multiple critical points of perturbed symmetric functionals.(English)Zbl 0589.35004

Summary: Variational problems which are invariant under a group of symmetries often possess multiple solutions. This paper studies the effect of perturbations which are not small and which destroy the symmetry for two classes of such problems and shows how multiple solutions persist despite the perturbation.

### MSC:

 35A15 Variational methods applied to PDEs 35J20 Variational methods for second-order elliptic equations 35B20 Perturbations in context of PDEs

### Keywords:

Variational problems; multiple solutions; perturbations
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### References:

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