Central Limit Theorem for a Class of One-dimensional Kinetic Equations

We introduce a class of Boltzmann equations on the real line, which constitute extensions of the classical Kac caricature. The collisional gain operators are defined by smoothing transformations with quite general properties. By establishing a connection to the central limit problem, we are able to prove long-time convergence of the equation’s solutions towards a limit distribution. If the initial condition for the Boltzmann equation belongs to the domain of normal attraction of a certain stable law gα, then the limit is non-trivial and is a scale mixture of gα. Under some additional assumptions, explicit exponential rates for the equilibration in Wasserstein metrics are calculated, and strong convergence of the probability densities is shown.