Nontrivial solutions for superquadratic nonautonomous periodic systems
We consider a nonautonomous second order periodic system with an indefinite linear part. We assume that the potential function is superquadratic, but it may not satisfy the Ambrosetti-Rabinowitz condition. Using an existence result for $C^1$-functionals having a local linking at the origin, we show that the system has at least one nontrivial solution.
superquadratic potential, AR-condition, spectral resolution, local linking, C-condition, periodic solution
Hu, Shouchuan, and Nikolaos S. Papageorgiou. "Nontrivial solutions for superquadratic nonautonomous periodic systems." Topological Methods in Nonlinear Analysis 34, no. 2 (2009): 327-338.
Topological Methods in Nonlinear Analysis