Boundary Value Problems
Volume 2008 (2008), Article ID 305291, 22 pages
doi:10.1155/2008/742030

Critical point theory applied to a class of the systems of the superquadratic wave equations

Tacksun Jung1 and Q-Hueng Choi2

1Department of Mathematics, Kunsan National University, Kunsan 573-701, South Korea
2Department of Mathematics Education, Inha University, Incheon 402-751, South Korea

Abstract

We show the existence of a nontrivial solution for a class of the systems of the superquadratic nonlinear wave equations with Dirichlet boundary conditions and periodic conditions with a superquadratic nonlinear terms at infinity which have continuous derivatives. We approach the variational method and use the critical point theory which is the Linking Theorem for the strongly indefinite corresponding functional.