title: Thermodynamic formalism for the Lorentz gas with open boundaries in d dimensions.
abstract: A Lorentz gas may be defined as a system of fixed dispersing scatterers, with a single light particle moving among these and making specular collisions on encounters with the scatterers. For a dilute Lorentz gas with open boundaries in d dimensions we relate the thermodynamic formalism to a random flight problem. Using this representation we analytically calculate the central quantity within this formalism, the topological pressure, as a function of system size and a temperaturelike parameter beta . The topological pressure is given as the sum of the topological pressure for the closed system and a diffusion term with a beta-dependent diffusion coefficient. From the topological pressure we obtain the Kolmogorov-Sinai entropy on the repeller, the topological entropy, and the partial information dimension.
authors.affiliation: Institute for Theoretical Physics, Utrecht University, Leuvenlaan 4, 3584 CE Utrecht, The Netherlands. H.vanBeijeren@phys.uu.nl
authors.forename: Henk
authors.initials: H
authors.lastname: van Beijeren
authors.forename: Oliver
authors.initials: O
authors.lastname: Mülken