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Updated: Aug 6, 2026
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Visually Based Characterization of the Incipient Particle Motion in Regular Substrates: From Laminar to Turbulent Conditions
Published on: February 22, 2018
Hydrodynamic theory of wetting by active particles
Noah Grodzinski1, Michael E Cates1, Robert L Jack1,2
1University of Cambridge, Department of Applied Mathematics and Theoretical Physics, Wilberforce Road, Cambridge, United Kingdom.
Physical Review. E
|July 24, 2026
Summary
Active wetting, where self-propelled particles accumulate on barriers, mirrors equilibrium wetting transitions. This study reveals unique nonequilibrium effects like spontaneous currents and altered densities in active matter systems.
Area of Science:
- Active Matter Physics
- Soft Condensed Matter
Background:
- Wetting phenomena are crucial in biological processes like biofilm formation.
- The behavior of self-propelled particles at surfaces (active wetting) is not fully understood.
- Active matter systems exhibit complex dynamics distinct from equilibrium systems.
Purpose of the Study:
- To investigate active wetting using a precisely defined model.
- To compare active wetting phenomena with equilibrium wetting transitions.
- To explore nonequilibrium effects unique to active wetting.
Main Methods:
- Studied an active lattice gas model interacting with a permeable barrier.
- Employed periodic boundary conditions for an exact hydrodynamic description.
- Utilized a hydrodynamic scaling limit to remove noise and enable precise characterization.
Main Results:
- Active wetting transitions show strong similarities to equilibrium critical wetting.
- Identified unique nonequilibrium effects: spontaneous ratchet effect, global steady-state current.
- Observed departures of bulk densities from binodal values and modified transition pathways.
Conclusions:
- Developed a nonequilibrium framework for studying active wetting.
- Demonstrated connections between active and passive wetting phenomena.
- Clarified the distinct consequences of activity in wetting transitions.
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