Effective integrable dynamics for some nonlinear wave equation
arXiv:1110.5719
Abstract
We consider the following degenerate half wave equation on the one dimensional torus We show that, on a large time interval, the solution may be approximated by the solution of a completely integrable system-- the cubic Szegö equation. As a consequence, we prove an instability result for large norms of solutions of this wave equation.
19 pages