Existence of four solutions of some nonlinear Hamiltonian system.
Existence of homoclinic orbits for Hamiltonian systems with superquadratic potentials.
Existence of periodic solutions of linear Hamiltonian systems with sublinear perturbation.
Existence of solutions and of multiple solutions for nonlinear nonsmooth periodic systems
In this paper we examine nonlinear periodic systems driven by the vectorial -Laplacian and with a nondifferentiable, locally Lipschitz nonlinearity. Our approach is based on the nonsmooth critical point theory and uses the subdifferential theory for locally Lipschitz functions. We prove existence and multiplicity results for the “sublinear” problem. For the semilinear problem (i.e. ) using a nonsmooth multidimensional version of the Ambrosetti-Rabinowitz condition, we prove an existence theorem...
Existence of solutions for a nonlinear discrete system involving the -Laplacian
The existence of solutions for boundary value problems for a nonlinear discrete system involving the -Laplacian is investigated. The approach is based on critical point theory.
Existence of solutions to a Hamiltonian system without convexity condition on the nonlinearity.