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Updated: Jul 4, 2026
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Visually Based Characterization of the Incipient Particle Motion in Regular Substrates: From Laminar to Turbulent Conditions
Published on: February 22, 2018
Collective motion of self-propelled particles interacting without cohesion
Hugues Chaté1, Francesco Ginelli, Guillaume Grégoire
1CEA-Service de Physique de l'Etat Condensé, Centre d'Etudes de Saclay, 91191 Gif-sur-Yvette, France.
Summary
This study reveals that Vicsek-style self-propelled particle models exhibit a discontinuous transition to collective motion. Propagating solitary structures dominate near the transition, while a homogeneous phase with strong fluctuations appears farther away.
Area of Science:
- Complex systems
- Statistical physics
- Non-equilibrium dynamics
Background:
- Vicsek-style models are fundamental for understanding collective behavior in systems with local alignment.
- Stochasticity and dimensionality significantly influence emergent phenomena.
- Characterizing phase transitions is crucial for predicting system-level behaviors.
Purpose of the Study:
- To comprehensively study Vicsek-style self-propelled particle models in 2D and 3D.
- To analyze the nature of the transition to collective motion.
- To investigate the properties of the ordered phase and its dependence on model parameters.
Main Methods:
- Simulations of Vicsek-style self-propelled particle models.
- Analysis of systems in two and three space dimensions.
- Investigation of parameter space, focusing on the transition region and homogeneous phases.
Main Results:
- The onset of collective motion is discontinuous (first-order-like).
- Propagating solitary structures (high-density, high-order) dominate dynamics near the transition.
- Far from the transition, a statistically homogeneous ordered phase emerges, exhibiting strong density fluctuations, superdiffusion, and intermittency.
Conclusions:
- The collective motion transition in Vicsek models is abrupt and exhibits distinct phases.
- The presence and dominance of solitary structures are sensitive to proximity to the transition.
- Anomalous behaviors like superdiffusion and intermittency characterize the homogeneous ordered phase.
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