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Entropy production along a stochastic trajectory and an integral fluctuation theorem
1II. Institut für Theoretische Physik, Universität Stuttgart, Germany.
Physical Review Letters
|August 11, 2005
Summary
This study investigates entropy production in stochastic nonequilibrium systems. A fluctuation theorem is demonstrated for the total entropy change along single trajectories, applicable to various systems and conditions.
Area of Science:
- Physics
- Physical Chemistry
- Statistical Mechanics
Background:
- Stochastic nonequilibrium dynamics are crucial for understanding systems far from equilibrium.
- Entropy production is a key concept in thermodynamics, quantifying irreversibility.
Purpose of the Study:
- To study entropy production along single trajectories for stochastic nonequilibrium dynamics.
- To analyze the contributions of particle entropy and surrounding medium entropy.
- To demonstrate a fluctuation theorem for total entropy change.
Main Methods:
- Analysis of stochastic processes described by Langevin or master equations.
- Calculation of entropy production for individual trajectories.
- Integration of entropy changes over finite time intervals.
Main Results:
- Entropy production includes genuine particle entropy and medium entropy.
- The integrated total entropy change, ΔS(tot), obeys a fluctuation theorem.
- The theorem holds for arbitrary initial conditions and time-dependent driving.
Conclusions:
- A universal fluctuation theorem governs total entropy production in stochastic nonequilibrium systems.
- This finding provides insights into the thermodynamics of small systems and irreversible processes.
- The results are applicable to diverse systems like colloidal particles and discrete state models.
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