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Dynamics of condensation in zero-range processes

C. Godreche
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Abstract

The dynamics of a class of zero-range processes exhibiting a condensation transition in the stationary state is studied. The system evolves in time starting from a random disordered initial condition. The analytical study of the large-time behaviour of the system in its mean-field geometry provides a guide for the numerical study of the one-dimensional version of the model. Most qualitative features of the mean-field case are still present in the one-dimensional system, both in the condensed phase and at criticality. In particular the scaling analysis, valid for the mean-field system at large time and for large values of the site occupancy, still holds in one dimension. The dynamical exponent $z$, characteristic of the growth of the condensate, is changed from its mean-field value 2 to 3. In presence of a bias, the mean-field value $z=2$ is recovered. The dynamical exponent $z_c$, characteristic of the growth of critical fluctuations, is changed from its mean-field value 2 to a larger value, $z_c\simeq 5$. In presence of a bias, $z_c\simeq 3$.

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C. Godreche. 2003-01-29. Dynamics of condensation in zero-range processes. https://arxiv.org/abs/cond-mat/0301156

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