ATTRACTORS AND TRANSIENTS FOR A PERTURBED PERIODIC KDV EQUATION - A NONLINEAR SPECTRAL-ANALYSIS

In this paper we rigorously show the existence and smoothness in epsilon of traveling wave solutions to a periodic Korteweg-deVries equation with a Kuramoto-Sivashinsky-type perturbation for sufficiently small values of the perturbation parameter epsilon. The shape and the spectral transforms of these traveling waves are calculated perturbatively to first order. A linear stability theory using squared eigenfunction bases related to the spectral theory of the KdV equation is proposed and carried out numerically. Finally, the inverse spectral transform is used to study the transient and asymptotic stages of the dynamics of the solutions.