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The Diffusion of Passive Tracers in Laminar Shear Flow
Published on: May 1, 2018
Characterizing steady-state and transient properties of reaction-diffusion systems
Sven Dorosz1, Michel Pleimling
1Department of Physics, Virginia Polytechnic Institute and State University, Blacksburg, Virginia 24061-0435, USA.
Summary
This study analyzes diffusion-limited reactions, revealing unique transient behaviors using a novel work observable. Findings highlight how microscopic dynamics influence fluctuation ratios in systems far from equilibrium.
Area of Science:
- Statistical Physics
- Non-equilibrium Thermodynamics
- Chemical Kinetics
Background:
- Reaction-diffusion systems are crucial for understanding far-from-equilibrium many-body systems.
- Microscopic reversibility is often broken in these systems, complicating the study of transient behaviors.
- Existing observables are insufficient for analyzing systems lacking microscopic reversibility.
Purpose of the Study:
- To characterize diffusion-limited reactions in both steady and non-steady states.
- To analyze transient properties of reaction-diffusion systems lacking microscopic reversibility.
- To investigate fluctuation ratios of probability distributions in driven systems.
Main Methods:
- Development and application of a specific work observable, valid even without microscopic reversibility.
- Driving systems out of non-equilibrium steady states using time-dependent reaction rates.
- Numerical exact methods and computer simulations to analyze forward and reversed processes.
Main Results:
- The work observable obeys an exact detailed fluctuation relation when detailed balance is fulfilled.
- Analysis of fluctuation ratios reveals prominent features arising from underlying microscopic dynamics.
- Configuration-space trajectories exhibit peculiarities influenced by microscopic dynamics.
Conclusions:
- The proposed work observable provides a robust method for studying transient properties in systems with broken microscopic reversibility.
- Microscopic dynamics significantly impact fluctuation ratios, offering new insights into non-equilibrium systems.
- This approach enhances the understanding of complex behaviors in diffusion-limited reactions.
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