Stable and unstable time quasi periodic solutions for a system of coupled NLS equations
arXiv:1710.09173 · doi:10.1088/1361-6544/aad3d9
Abstract
We prove that a system of coupled nonlinear Schr{ö}dinger equations on the torus exhibits both stable and unstable small KAM tori. In particular the unstable tori are related to a beating phenomena which has been proved recently in [6]. This is the first example of unstable tori for a 1d PDE.