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Fluctuation theorems and entropy production with odd-parity variables.
Hyun Keun Lee1, Chulan Kwon, Hyunggyu Park
1Department of Physics, University of Seoul, Seoul 130-743, Korea.
Physical Review Letters
|February 19, 2013
Summary
Total entropy production in stochastic processes is split into three parts. Only two parts generally satisfy fluctuation theorems, with implications for understanding equilibrium and detailed balance in systems with odd-parity variables.
Area of Science:
- Statistical physics
- Non-equilibrium thermodynamics
- Stochastic processes
Background:
- Integral fluctuation theorems (FTs) are crucial for understanding non-equilibrium systems.
- Entropy production is a key quantity in characterizing the irreversibility of stochastic processes.
- Odd-parity variables under time reversal present unique challenges in thermodynamic analysis.
Purpose of the Study:
- To investigate the behavior of total entropy production in stochastic systems with odd-parity variables.
- To determine which components of entropy production satisfy integral fluctuation theorems.
- To elucidate the conditions required for thermodynamic equilibrium in such systems.
Main Methods:
- Analysis of total entropy production in stochastic processes.
- Separation of entropy production into distinct contributions based on parity and time-reversal symmetry.
- Examination of the conditions under which integral fluctuation theorems are satisfied.
Main Results:
- Total entropy production is decomposed into three parts: nonadiabatic excess, detailed balance breakage, and steady-state distribution asymmetry.
- Only the nonadiabatic excess and detailed balance breakage contributions generally satisfy integral fluctuation theorems.
- The housekeeping (adiabatic) contribution, combining the latter two, is not always positive, impacting equilibrium conditions.
Conclusions:
- Equilibrium in systems with odd-parity variables requires independent steady-state distribution symmetry, beyond detailed balance.
- The study clarifies the limitations of integral fluctuation theorems for specific entropy production components.
- Findings offer new insights into the thermodynamics of non-equilibrium systems with time-reversal symmetry breaking.
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