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Phase Transitions and superuniversality in the dynamics of a self-driven particle

R. Grima
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Abstract

We study an active random walker model in which a particle's motion is determined by a self-generated field. The field encodes information about the particle's path history. This leads to either self-attractive or self-repelling behavior. For self-repelling behavior, we find a phase transition in the dynamics: when the coupling between the field and the walker exceeds a critical value, the particle's behavior changes from renormalized diffusion to one characterized by a diverging diffusion coefficient. The dynamical behavior for all cases is surprisingly independent of dimension and of the noise amplitude.

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R. Grima. 2006-07-20. Phase Transitions and superuniversality in the dynamics of a self-driven particle. https://doi.org/10.1103/physreve.74.011125

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