Chris Lutsko, Univ. of Bristol

The low density limit of the periodic Lorentz gas with polyhedral scatterers.

Abstract: We study the dynamics of a point particle moving through a periodic array of polyhedral scatterers in the low-density Boltzmann-Grad limit. Building on previous results of Marklof and Strömbergsson for spherical scatterers we establish a limiting stochastic process governing the dynamics. Moreover we find that the dynamics depends strongly on the shape of the polyhedra and on the sequence of sides hit by the point particle. This is joint work with Jens Marklof.