Fe b 20 04 Condensation transition in zero - range processes with diffusion
نویسندگان
چکیده
Recent studies have indicated that the coarse grained dynamics of a large class of traffic models and driven-diffusive systems may be described by urn models. We consider a class of one-dimensional urn models whereby particles hop from an urn to its nearest neighbor by a rate which decays with the occupation number k of the departure site as (1 + b/k). In addition a diffusion process takes place, whereby all particles in an urn may hop to an adjacent one with some rate α. Condensation transition which may take place in this model is studied and the (b, α) phase diagram is calculated within the mean field approximation and by numerical simulations. A driven-diffusive model whose coarse grained dynamics corresponds to this urn model is considered.
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