Multiplicity Theorems for Frechet Manifolds

Abstract

We prove multiplicity theorems for Keller $C_c^1$-functionals on Frechet spaces and Finsler manifolds which are invariant under the action of a discrete subgroup. For such functionals, we evaluate the minimal number of critical points by applying the Lusternik-Schnirelmann category.

To appear in Reports of the National Academy of Sciences of Ukraine. arXiv admin note: text overlap with arXiv:2205.01359