title: Effect of spatial bias on the nonequilibrium phase transition in a system of coagulating and fragmenting particles.
abstract: We examine the effect of spatial bias on a nonequilibrium system in which masses on a lattice evolve through the elementary moves of diffusion, coagulation, and fragmentation. When there is no preferred directionality in the motion of the masses, the model is known to exhibit a nonequilibrium phase transition between two different types of steady state, in all dimensions. We show analytically that introducing a preferred direction in the motion of the masses inhibits the occurrence of the phase transition in one dimension, in the thermodynamic limit. A finite-size system, however, continues to show a signature of the original transition, and we characterize the finite-size scaling implications of this. Our analysis is supported by numerical simulations. In two dimensions, bias is shown to be irrelevant.
authors.affiliation: Department of Physics-Theoretical Physics, University of Oxford, 1 Keble Road, United Kingdom. r.ravindran1@physics.ox.ac.uk
authors.forename: R
authors.initials: R
authors.lastname: Rajesh
authors.forename: Supriya
authors.initials: S
authors.lastname: Krishnamurthy