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Novel type of phase transition in a system of self-driven particles

Tamas Vicsek·Andras Czirok·Eshel Ben-Jacob·Inon Cohen·Ofer Sochet
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Abstract

A simple model with a novel type of dynamics is introduced in order to investigate the emergence of self-ordered motion in systems of particles with biologically motivated interaction. In our model particles are driven with a constant absolute velocity and at each time step assume the average direction of motion of the particles in their neighborhood with some random perturbation ($η$) added. We present numerical evidence that this model results in a kinetic phase transition from no transport (zero average velocity, $| {\bf v}_a | =0$) to finite net transport through spontaneous symmetry breaking of the rotational symmetry. The transition is continuous since $| {\bf v}_a |$ is found to scale as $(η_c-η)^β$ with $β\simeq 0.45$.

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Tamas Vicsek, Andras Czirok, Eshel Ben-Jacob, Inon Cohen, Ofer Sochet. 2006-11-29. Novel type of phase transition in a system of self-driven particles. https://doi.org/10.1103/physrevlett.75.1226

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