title: Nonadditivity of fluctuation-induced forces in fluidized granular media.
abstract: We investigate the effective long-range interactions between intruder particles immersed in a randomly driven granular fluid. The effective Casimir-like force between two intruders, induced by the fluctuations of the hydrodynamic fields, can change its sign when varying the control parameters: the volume fraction, the distance between the intruders, and the restitution coefficient. More interestingly, by inserting more intruders, we verify that the fluctuation-induced interaction is not pairwise additive. The simulation results are qualitatively consistent with the theoretical predictions based on mode coupling calculations. These results shed new light on the underlying mechanisms of collective behaviors in fluidized granular media.
authors.affiliation: Department of Theoretical Physics, University of Duisburg-Essen, 47048 Duisburg, Germany. reza.shaebani@uni-due.de
authors.forename: M Reza
authors.initials: MR
authors.lastname: Shaebani
authors.forename: Jalal
authors.initials: J
authors.lastname: Sarabadani
authors.forename: Dietrich E
authors.initials: DE
authors.lastname: Wolf
mesh_terms: D045424:Complex Mixtures / Q000737:chemistry*; D003198:Computer Simulation; D008956:Models, Chemical
chemical_list: D045424:Complex Mixtures