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arXiv · 1208.4089

Entrainment and unit velocity: Surprises in an accelerated exclusion process

Jiajia Dong·Stefan Klumpp·Royce K. P. Zia
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Abstract

We introduce a class of distance-dependent interactions in an accelerated exclusion process (AEP) inspired by the observation of transcribing RNA polymerase speeding up when "pushed" by a trailing one. On a ring, the AEP steady state displays a discontinuous transition, from being homogeneous (with augmented currents) to phase-segregated. In the latter state, the holes appear loosely bound and move together, much like a train. Surprisingly, the current-density relation is simply $J=1-ρ$, signifying that the "hole-train" travels with \textit{unit} velocity.

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Jiajia Dong, Stefan Klumpp, Royce K. P. Zia. 2012-08-20. Entrainment and unit velocity: Surprises in an accelerated exclusion process. https://doi.org/10.1103/physrevlett.109.130602

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