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arXiv · 1204.1804

Dominance of extreme statistics in a prototype many-body Brownian ratchet

Evan Hohlfeld·Phillip L. Geissler
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Abstract

Many forms of cell motility rely on Brownian ratchet mechanisms that involve multiple stochastic processes. We present a computational and theoretical study of the nonequilibrium statistical dynamics of such a many-body ratchet, in the specific form of a growing polymer gel that pushes a diffusing obstacle. We find that oft-neglected correlations among constituent filaments impact steady-state kinetics and significantly deplete the gel's density within molecular distances of its leading edge. These behaviors are captured quantitatively by a self-consistent theory for extreme fluctuations in filaments' spatial distribution.

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Evan Hohlfeld, Phillip L. Geissler. 2014-11-05. Dominance of extreme statistics in a prototype many-body Brownian ratchet. https://doi.org/10.1063/1.4899052

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