title: Active and passive particles: modeling beads in a bacterial bath.
abstract: A simple model for the motion of passive particles in a bath of active, self-propelled ones is introduced. It is argued that this approach provides the correct framework within which to cast the recent experimental results obtained by Wu and Libchaber [Phys Rev. Lett. 84, 3017 (2000)] for the diffusive properties of polystyrene beads displaced by bacteria suspended in a two-dimensional fluid film. Our results suggest that superdiffusive behavior should indeed be generically observed in the transition region marking the onset of collective motion.
authors.affiliation: CEA, Service de Physique de l'Etat Condensé, Centre d'Etudes de Saclay, 91191, Gif-sur-Yvette, France.
authors.forename: G
authors.initials: G
authors.lastname: Grégoire
authors.forename: H
authors.initials: H
authors.lastname: Chaté
authors.forename: Y
authors.initials: Y
authors.lastname: Tu
mesh_terms: D018407:Bacterial Physiological Phenomena; D055592:Biophysical Phenomena; D001703:Biophysics; D004058:Diffusion; D008954:Models, Biological; D015233:Models, Statistical; D011137:Polystyrenes / Q000737:chemistry*; D013997:Time Factors
chemical_list: D011137:Polystyrenes