Thierry Bodineau

Joint PAD seminar: Perturbative regimes for deterministic dynamics of a diluted gas of hard spheres

We consider a dilute gas of hard spheres evolving according to Newtonian dynamics and starting close to equilibrium. We will show that, in the Boltzmann Grad limit, the linear and linearized Boltzmann equations can be recovered up to any large time. As a consequence, we prove that a tagged particle behaves as a Brownian motion after rescaling.