Finite-size effects on the dynamics of the zero-range process

TL;DR

This paper investigates how finite system size influences the dynamics of a one-dimensional zero-range process, revealing distinct fluctuation behaviors in disordered and condensed phases.

Contribution

It provides a detailed analysis of finite-size effects on current fluctuations and condensate dynamics in the zero-range process, highlighting phase-dependent behaviors.

Findings

Disordered phase exhibits damped oscillations in current variance.

Condensed phase shows long-time condensate relocation dynamics.

Finite-size effects significantly alter fluctuation patterns in both phases.

Abstract

We study finite-size effects on the dynamics of a one-dimensional zero-range process which shows a phase transition from a low-density disordered phase to a high-density condensed phase. The current fluctuations in the steady state show striking differences in the two phases. In the disordered phase, the variance of the integrated current shows damped oscillations in time due to the motion of fluctuations around the ring as a dissipating kinematic wave. In the condensed phase, this wave cannot propagate through the condensate, and the dynamics is dominated by the long-time relocation of the condensate from site to site.