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Universal theory of efficiency fluctuations
Gatien Verley1, Tim Willaert2, Christian Van den Broeck2
1Complex Systems and Statistical Mechanics, University of Luxembourg, L-1511 Luxembourg, G.D. Luxembourg.
Physical Review. E, Statistical, Nonlinear, and Soft Matter Physics
|December 11, 2014
Summary
This study reveals universal features of machine efficiency fluctuations using the fluctuation theorem. It shows probabilities for reversible and least likely efficiencies are identical under time-reversed driving.
Area of Science:
- Thermodynamics
- Statistical Mechanics
- Non-equilibrium Systems
Background:
- Understanding efficiency fluctuations is crucial for designing optimal thermal and isothermal machines.
- Current models often simplify driving conditions, limiting applicability to complex, non-equilibrium scenarios.
Purpose of the Study:
- To derive universal features of long-time efficiency fluctuations for machines under various driving conditions.
- To investigate the relationship between efficiency fluctuations and time-reversed processes.
Main Methods:
- Application of the fluctuation theorem.
- Incorporation of geometric arguments.
- Analysis of steady and periodic driving protocols.
Main Results:
- Identical probabilities for observing reversible and least likely efficiencies under time-reversed driving.
- Coincidence of reversible and least probable efficiencies for time-symmetric drivings.
- Universal features applicable to systems close or far from equilibrium.
Conclusions:
- The fluctuation theorem provides a powerful framework for understanding efficiency fluctuations.
- Geometric arguments reveal fundamental symmetries in non-equilibrium thermodynamics.
- Findings offer insights into the fundamental limits and behaviors of energy conversion machines.
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