Landau Damping and Related Phenomena

The physical interpretation of the Vlasov equation singularity-related phenomena, i.e., Landau damping, quasi-linear phase-space diffusion, and wave-wave scattering is sought by deriving these phenomena avoiding singularities. The net impulse experienced by a particle in the presence of a damped wave is calculated; and a Fokker-Planck-like equation is constructed to describe the evolution of an ensemble of particles interacting with such waves. The three phenomena are seen to arise directly from the fact that a particle experiences a net impulse in the presence of waves which are growing or damping.