Dynamical Self-regulation in Self-propelled Particle Flows

Arvind Gopinath; Michael F. Hagan; M. Cristina Marchetti; Aparna Baskaran

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arXiv · 1112.6011

Dynamical Self-regulation in Self-propelled Particle Flows

Arvind Gopinath·Michael F. Hagan·M. Cristina Marchetti·Aparna Baskaran

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Abstract

We study a continuum model of overdamped self-propelled particles with an aligning interaction in two dimensions. By combining analytical and numerical work, we map out the phase diagram for generic parameters. We find that the system self-organizes into two robust structures in different regions of parameter space: solitary waves of ordered swarms moving through a low density disordered background, and stationary asters. The self-regulating nature of the flow yields phase separation, ubiquitous in this class of systems, and controls the formation of solitary waves. Self-propulsion and the associated active convection play a crucial role in aster formation. A new result of our work is a phase diagram that displays these different regimes in a unified manner.

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Arvind Gopinath, Michael F. Hagan, M. Cristina Marchetti, Aparna Baskaran. 2011-12-27. Dynamical Self-regulation in Self-propelled Particle Flows. https://arxiv.org/abs/1112.6011

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