文摘
Under super or asymptotically quadratic assumptions at infinity, we obtain the existence of nontrivial ground state homoclinic orbits for a class of second-order Hamiltonian systems with general potentials by a variant generalized weak linking theorem. For the asymptotically quadratic case, a necessary and sufficient condition is obtained for the existence of nontrivial homoclinic orbits. For the superquadratic case, we use general superquadratic conditions to replace the Ambrosetti–Rabinowitz condition.