NONTRIVIAL SOLUTIONS FOR ASYMPTOTICALLY LINEAR HAMILTONIAN SYSTEMS WITH LAGRANGIAN BOUNDARY CONDITIONS

In this article, we study the existence of nontrivial solutions for a class of asymptotically linear Hamiltonian systems with Lagrangian boundary conditions by the Galerkin approximation methods and the L-index theory developed by the first author.     

HOMOCLINIC SOLUTIONS NEAR THE ORIGIN FOR A CLASS OF FIRST ORDER HAMILTONIAN SYSTEMS

In this paper, we study the existence of infinitely many homoclinic solutions for a class of first order Hamiltonian systems ■= JHz_{t, z}, where the Hamiltonian function H possesses the form H(t, z) =1/2L(t)z·z + G(t, z), and G(t, z) is only locally defined near the origin with respect to z. Under some mild conditions on L and G, we show that the existence of a sequence of homoclinic solutions is actually a local phenomenon in some sense, which is essentially forced by the subquadratici...