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Dense polar active fluids in a disordered environment
Riccardo Ben Alì Zinati1, Marc Besse1, Gilles Tarjus1
1Sorbonne University, CNRS-UMR7600, Laboratoire de Physique Théorique de la Matière Condensée, F-75005, Paris, France.
Physical Review. E
|July 20, 2022
Summary
Quenched disorder in active matter influences flocking transitions. Both random forces and dilution lead to a new universality class, controlled by a quenched Navier-Stokes fixed point.
Area of Science:
- Physics
- Soft Matter Physics
- Statistical Mechanics
Background:
- Dense polar active matter exhibits flocking transitions.
- Quenched disorder can significantly alter system dynamics.
Purpose of the Study:
- To investigate the impact of quenched disorder on flocking transitions in active matter.
- To characterize the universality class and scaling behavior under disorder.
Main Methods:
- Analysis of incompressible active particle systems with aligning interactions.
- Inclusion of quenched random forces or random dilution (mass).
- Perturbative renormalization group analysis to determine critical exponents.
Main Results:
- A continuous disorder-order (flocking) transition is observed.
- The system's scaling behavior is governed by a novel universality class.
- This class is controlled by a quenched Navier-Stokes fixed point.
- Both random forces and random mass belong to the same universality class.
Conclusions:
- Quenched disorder introduces a new universality class for flocking transitions in active matter.
- The universality class is distinct from equilibrium systems.
- The findings provide insights into the fundamental behavior of disordered active systems.
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