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Updated: Dec 26, 2025

Author Spotlight: Collective Behavioral Analysis of the Nematode, Caenorhabditis elegans
Published on: August 25, 2023
Spatial organization of active particles with field-mediated interactions.
Ruben Zakine1, Jean-Baptiste Fournier1, Frédéric van Wijland1
1Université de Paris, Laboratoire Matière et Systèmes Complexes (MSC), UMR 7057 CNRS, F-75205 Paris, France.
This study reveals how nonequilibrium noise drives spatial patterns in Brownian particle systems. The research maps phase diagrams, highlighting the impact of internal states on particle organization.
Area of Science:
- Statistical Physics
- Soft Matter Physics
- Nonlinear Dynamics
Background:
- Modeling Brownian motion of pointlike particles interacting with a fluctuating Gaussian background.
- Incorporating a two-state internal degree of freedom subjected to nonequilibrium noise.
- Investigating how internal states influence particle-environment coupling.
Purpose of the Study:
- To explore the phase diagram of the described particle system.
- To identify the role of nonequilibrium drive in spatial pattern formation.
- To analyze the parameter-dependence of phase and pattern boundaries.
Main Methods:
- Weakly nonlinear analysis.
- Phase diagram exploration.
- Stationary state analysis.
Main Results:
- Identification of a nontrivial patterned spatial organization driven by nonequilibrium noise.
- Characterization of the system's phase and pattern diagram boundaries.
- Demonstration of the influence of the internal degree of freedom on collective behavior.
Conclusions:
- Nonequilibrium noise is a key factor in generating spatial patterns in such systems.
- The internal two-state dynamics significantly affect particle organization and system phase.
- Weakly nonlinear analysis provides a method to understand parameter-dependent pattern formation.
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