A minimax method for a class of Hamiltonian systems with singular potentials

@article{Bahri1989AMM,
title={A minimax method for a class of Hamiltonian systems with singular potentials},
author={A. Bahri and P. H. Rabinowitz},
journal={Journal of Functional Analysis},
year={1989},
volume={82},
pages={412-428}
}

Abstract This paper presents a minimax method which gives existence and multiplicity results for time periodic solutions of a class of Hamiltonian systems when a singular potential is present. The singularity satisfies the strong force condition of Gordon. When milder singularities are permitted a notion of generalized T -periodic solution is introduced and we get existence and multiplicity results for such solutions.