This paper is motivated by looking for a loop solution of the Hamiltonian systems such that (0.1) q'(t)+V′(q(t))=0 for t∈ with some T>0 and (0.2) 12|q′(t)| 2+V(q(t))=h ...This paper is motivated by looking for a loop solution of the Hamiltonian systems such that (0.1) q'(t)+V′(q(t))=0 for t∈ with some T>0 and (0.2) 12|q′(t)| 2+V(q(t))=h for t∈ with q(0)=q(T)=x 0 where q∈C 2(, R n 0}), n≥2, x 0∈R n 0} is a fixed point, h∈R is a given number, V∈C 2(R n 0}), R is a potential with a singularity and V′ denotes its gradient. Our main existence results are obtained by a appropriately defined lengthdecreasing (or rather energy decreasing) deformation and a min max procedure which is a combined version of Bahri Rabinowitz and Klingenberg . Our main assumptions are geodesic convex conditions found by the author and the strong force condition of Gordon . As a direct application, for the relativistic gravitational potential V(x)=|x| -1 +|x| -2 or its large scale perturbation, there always exists an almost periodic solution of (0.1)-(0.2) for any h∈R and any x 0∈R n 0} with | x 0 | small enough. This is an interesting phenomenon because we know that there exists no periodic solution of prescribed nonnegative energy for such a Hamiltonian system.展开更多
文摘This paper is motivated by looking for a loop solution of the Hamiltonian systems such that (0.1) q'(t)+V′(q(t))=0 for t∈ with some T>0 and (0.2) 12|q′(t)| 2+V(q(t))=h for t∈ with q(0)=q(T)=x 0 where q∈C 2(, R n 0}), n≥2, x 0∈R n 0} is a fixed point, h∈R is a given number, V∈C 2(R n 0}), R is a potential with a singularity and V′ denotes its gradient. Our main existence results are obtained by a appropriately defined lengthdecreasing (or rather energy decreasing) deformation and a min max procedure which is a combined version of Bahri Rabinowitz and Klingenberg . Our main assumptions are geodesic convex conditions found by the author and the strong force condition of Gordon . As a direct application, for the relativistic gravitational potential V(x)=|x| -1 +|x| -2 or its large scale perturbation, there always exists an almost periodic solution of (0.1)-(0.2) for any h∈R and any x 0∈R n 0} with | x 0 | small enough. This is an interesting phenomenon because we know that there exists no periodic solution of prescribed nonnegative energy for such a Hamiltonian system.