Turbulent cascades for a family of damped Szegő equations

Abstract

Abstract In this paper, we study the transfer of energy from low to high frequencies for a family of damped Szegő equations. The cubic Szegő equation has been introduced as a toy model for a totally non-dispersive degenerate Hamiltonian equation. It is a completely integrable system which develops growth of high Sobolev norms, detecting transfer of energy and hence cascades phenomena. Here, we consider a two-parameter family of variants of the cubic Szegő equation and prove that, adding a damping term unexpectedly promotes the existence of turbulent cascades. Furthermore, we give a panorama of the dynamics for such equations on a six-dimensional submanifold.