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Controlling Flow Speeds of Microtubule-Based 3D Active Fluids Using Temperature
Published on: November 26, 2019
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Biased Ensembles of Pulsating Active Matter
William D Piñeros1, Étienne Fodor1
1University of Luxembourg, Department of Physics and Materials Science, L-1511 Luxembourg, Luxembourg.
Physical Review Letters
|February 10, 2025
Summary
We found links between particle packing and rare fluctuations in active particle systems. System geometry changes can lead to distinct dynamical states, revealing new insights into active matter behavior.
Area of Science:
- Physics
- Statistical Mechanics
- Soft Matter Physics
Background:
- Dense systems of active particles exhibit complex dynamics.
- Pulsation of particle size introduces unique challenges in understanding system behavior.
- Rare fluctuations and packing configurations are crucial for dense active matter.
Purpose of the Study:
- To explore connections between packing configurations and rare fluctuations in active particle systems.
- To investigate how system geometry influences dynamical states under size pulsation.
- To understand the emergence of order and transitions in biased active matter dynamics.
Main Methods:
- Utilizing large deviation theory to examine biased ensembles.
- Analyzing atypical realizations of dynamics with synchronized particle size.
- Investigating the role of system geometry and packing configurations.
Main Results:
- Discovered unexpected links between packing and rare fluctuations.
- Identified distinct dynamical states (high to vanishing pulsation current) emerging at high bias.
- Showcased transitions between states driven by geometry changes at fixed bias and density.
- Rationalized transitions via packing configurations (ordered vs. geometrically frustrated).
- Revealed a master curve correlating polydispersity and current in unbiased dynamics.
- Demonstrated propagation of deformation waves under specific geometries and local order biasing.
Conclusions:
- Packing configurations significantly influence rare fluctuations in active particle systems.
- System geometry is a key factor in controlling dynamical states and transitions.
- A predictive relationship exists between unbiased and biased dynamics through a master curve.
- Deformation waves can be induced and propagated via geometric control and local order.
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