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Entropy production from stochastic dynamics in discrete full phase space
Ian J Ford1, Richard E Spinney
1Department of Physics and Astronomy, University College London, Gower Street, London WC1E 6BT, United Kingdom.
Physical Review. E, Statistical, Nonlinear, and Soft Matter Physics
|September 26, 2012
Summary
Stochastic entropy production in physical systems has three components. Only two have a non-negative mean, with the third reflecting dynamic irreversibility and model limitations.
Area of Science:
- Thermodynamics
- Statistical Mechanics
- Physical Systems
Background:
- Stochastic entropy production quantifies irreversibility in systems interacting with their environment.
- Entropy production can be decomposed into components, with varying mean values.
- Detailed balance is a key concept in equilibrium statistical mechanics.
Purpose of the Study:
- To analyze the components of stochastic entropy production.
- To investigate the conditions under which the third component of entropy production arises.
- To illustrate entropy production using discrete models of physical systems.
Main Methods:
- Decomposition of stochastic entropy into three components.
- Analysis of system trajectories and mean entropy production.
- Modeling of particle drift and diffusion in discrete phase space.
- Inclusion of injection/removal processes and temperature gradients.
Main Results:
- Identified three components of stochastic entropy production.
- The third component is non-negative only under specific conditions related to time-reversal symmetry and stationary state asymmetry.
- Demonstrated entropy production dependence on model details.
Conclusions:
- The third component of entropy production signifies a failure to meet Loschmidt's dynamic reversibility criterion.
- Stochastic thermodynamics provides a framework to measure this failure.
- Model-dependent entropy production highlights the importance of detailed dynamics in physical systems.
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