Kinetics of self-induced aggregation in Brownian particles

Fabio Cecconi; Giuseppe Gonnella; Gustavo P. Saracco

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arXiv · cond-mat/0703438

Kinetics of self-induced aggregation in Brownian particles

Fabio Cecconi·Giuseppe Gonnella·Gustavo P. Saracco

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Abstract

We study a model of interacting random walkers that proposes a simple mechanism for the emergence of cooperation in group of individuals. Each individual, represented by a Brownian particle, experiences an interaction produced by the local unbalance in the spatial distribution of the other individuals. This interaction results in a nonlinear velocity driving the particle trajectories in the direction of the nearest more crowded regions; the competition among different aggregating centers generates nontrivial dynamical regimes. Our simulations show that for sufficiently low randomness, the system evolves through a coalescence behavior characterized by clusters of particles growing with a power law in time. In addition, the typical scaling properties of the general theory of stochastic aggregation processes are verified.

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Fabio Cecconi, Giuseppe Gonnella, Gustavo P. Saracco. 2007-03-16. Kinetics of self-induced aggregation in Brownian particles. https://arxiv.org/abs/cond-mat/0703438

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