Resumen de Notes on Multiple Periodic Solutions for Second Order Hamiltonian Systems
Yiwei Ye, Shan Liu
In this paper, we study the multiplicity of periodic solutions for the second order Hamiltonian systems u¨ + ∇F(t, u) = 0 with the boundary condition u(0) − u(T ) = u˙(0) − ˙u(T ) = 0, where the potential F is either subquadratic k(t)-concave or subquadratic μ(t)-convex. Based on the reduction method and a three-critical-point theorem due to Brezis and Nirenberg, we obtain the multiplicity results, which complement and sharply improve some related results in the literature.
