Periodic solutions of hamiltonian systems of 3-body type
Some existence and multiplicity results for periodic solutions of second order nonautonomous systems with the potentials changing sign are presented. The proofs of the existence results rely on the use of a linking theorem and the Mountain Pass theorem by Ambrosetti and Rabinowitz [2]. The multiplicity results are deduced by the study of constrained critical points of minimum or Mountain Pass type.
The existence of solutions with prescribed period for a class of Hamiltonian systems with a Keplerian singularity is discussed.
* Supported by Ministero dell’Università e della Ricerca Scientifica e Tecnologica (40% – 1993). ** Supported by Ministero dell’Università e della Ricerca Scientifica e Tecnologica (40% – 1993).The perturbation of critical values for continuous functionals is studied. An application to eigenvalue problems for variational inequalities is provided.