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Active matter at high density: Velocity distribution and kinetic temperature
Lorenzo Caprini1, Umberto Marini Bettolo Marconi1
1Dipartimento di Fisica, Universitá di Camerino, Via Madonna delle Carceri, I-62032 Camerino, Italy.
The Journal of Chemical Physics
|November 14, 2020
Summary
We studied active Brownian particles in dense systems, finding their velocity distribution changes from Mexican-hat to Gaussian as particle persistence increases. We derived an exact kinetic temperature formula for these non-equilibrium systems.
Area of Science:
- Physics
- Soft Matter Physics
- Statistical Mechanics
Background:
- Active Brownian particles exhibit complex non-equilibrium phases.
- Understanding their statistical properties is crucial for soft matter systems.
Purpose of the Study:
- Investigate velocity distribution and kinetic temperature in dense active Brownian particle systems.
- Analyze the impact of persistence time on these properties.
Main Methods:
- Numerical simulations of active Brownian particles.
- Theoretical analysis of velocity distribution and kinetic temperature.
- Derivation of analytical expressions for kinetic temperature.
Main Results:
- Observed a transition in velocity distribution shape (Mexican-hat to Gaussian) with changing persistence.
- Derived an exact analytical expression for kinetic temperature in dense non-equilibrium systems.
- Characterized the validity of the derived kinetic temperature formula.
Conclusions:
- The persistence time of active forces significantly influences particle velocity distributions.
- The derived kinetic temperature formula provides a valuable tool for studying dense active matter.
- This work advances the understanding of non-equilibrium statistical mechanics in active systems.
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