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Generic Properties of Stochastic Entropy Production
Simone Pigolotti1,2, Izaak Neri1,3, Édgar Roldán1
1Max Planck Institute for the Physics of Complex Systems, Nöthnitzerstraße 38, 01187 Dresden, Germany.
Physical Review Letters
|October 21, 2017
Summary
We developed a new method to study entropy production in complex systems. This approach simplifies analysis and reveals universal properties of nonequilibrium processes.
Area of Science:
- Statistical Mechanics
- Non-equilibrium Thermodynamics
- Stochastic Processes
Background:
- Entropy production is a key measure of irreversibility in physical systems.
- Analyzing entropy production in complex Langevin processes is challenging due to model dependence.
Purpose of the Study:
- To derive a general Itô stochastic differential equation for entropy production.
- To identify universal properties of entropy production in nonequilibrium Langevin processes.
- To establish an exact uncertainty equality for entropy production.
Main Methods:
- Derivation of an Itô stochastic differential equation for entropy production.
- Introduction of a random-time transformation.
- Analysis of the resulting drift-diffusion equation.
Main Results:
- Entropy production follows a universal one-dimensional drift-diffusion equation after random-time transformation.
- The transformation reveals generic properties of entropy production, independent of the physical model.
- An exact uncertainty equality was derived, relating Fano factors of entropy production and random time, generalized to non-steady states.
Conclusions:
- The random-time transformation provides a powerful, model-independent tool for studying entropy production.
- The derived uncertainty equality offers new insights into the statistical properties of nonequilibrium systems.
- This framework is applicable to various nonequilibrium Langevin processes, including non-steady-state conditions.
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