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Generic Coupling between Internal States and Activity Leads to Activation Fronts and Criticality in Active Systems
Hadrien-Matthieu Gascuel1,2, Parisa Rahmani3, Richard Bon1
1<a href="https://ror.org/02feahw73">CNRS</a>, <a href="https://ror.org/02v6kpv12">Centre de Recherches sur la Cognition Animale</a>, 118 route de Narbonne, F-31062 Toulouse Cedex 9, France.
Physical Review Letters
|August 19, 2024
Summary
Active systems with on/off particle movement exhibit critical behavior. This study reveals how these systems transition, showing emergent criticality and scale-invariant activity avalanches in collective motion.
Area of Science:
- Physics
- Statistical Mechanics
- Complex Systems
Background:
- Collective motion is crucial in biological and physical systems.
- Understanding the dynamics of active matter, where particles generate their own motion, is key.
- The role of intermittent self-propulsion in emergent behavior is not fully understood.
Purpose of the Study:
- To investigate the onset of collective motion in active systems with intermittent self-propulsion.
- To analyze the behavior of active two-state systems with off→on transitions.
- To explore the emergence of criticality and phase transitions in these systems.
Main Methods:
- Theoretical analysis of active two-state systems.
- Modeling particle self-propulsion switching between on and off states.
- Investigating system behavior in one-dimensional (1D) and two-dimensional (2D) spaces.
Main Results:
- An active two-state system with off→on transitions effectively behaves as a three-state system.
- A sharp phase transition is observed in 1D.
- Critical behavior with scale-invariant activity avalanches is found in 2D.
Conclusions:
- Criticality can naturally emerge in active systems through simple switching mechanisms.
- These findings offer insights into how collectives process and respond to environmental cues.
- The study provides a framework for understanding emergent collective motion in active matter.
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