Invasion-wave induced first-order phase transition in systems of active particles

Thomas Ihle

doi:10.1103/physreve.88.040303

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arXiv · 1304.0149

Invasion-wave induced first-order phase transition in systems of active particles

Thomas Ihle

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Abstract

An Enskog-like kinetic equation for self-propelled particles is solved numerically. I study a density instability near the transition to collective motion and find that while hydrodynamics breaks down, the kinetic approach leads to soliton-like supersonic waves with steep leading kinks and Knudsen numbers of order one. These waves show hysteresis, modify the transition threshold and lead to an abrupt jump of the global order parameter if the noise level is changed. Thus they provide a mechanism to change the second-order character of the phase transition to first order.

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Thomas Ihle. 2013-03-31. Invasion-wave induced first-order phase transition in systems of active particles. https://doi.org/10.1103/physreve.88.040303

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