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Generalized detailed fluctuation theorem under nonequilibrium feedback control.
1The Institute of Mathematical Sciences, C.I.T. Campus, Taramani, Chennai 600113, India. mpn@imsc.res.in
Physical Review. E, Statistical, Nonlinear, and Soft Matter Physics
|January 15, 2011
Summary
Feedback control in physical systems preserves the detailed fluctuation theorem when the feedback information measure is consistent in forward and reverse directions. This research generalizes fluctuation theorems for nonequilibrium systems under feedback.
Area of Science:
- Thermodynamics
- Statistical Mechanics
- Non-equilibrium Physics
Background:
- The Jarzynski equality relates equilibrium free energy differences to nonequilibrium work fluctuations.
- Generalized Jarzynski equality and detailed fluctuation theorem have been established under nonequilibrium feedback control.
- Previous work proved generalized Jarzynski equality assuming local detailed fluctuation theorem satisfaction under feedback.
Purpose of the Study:
- To derive the generalized detailed fluctuation theorem for nonequilibrium driven systems under feedback control.
- To investigate the conditions under which feedback control preserves the detailed fluctuation theorem.
Main Methods:
- Utilized the same formalism as previous studies on generalized Jarzynski equality under feedback control.
- Derived a generalized detailed fluctuation theorem applicable to systems with feedback.
Main Results:
- Demonstrated that feedback control can preserve the detailed fluctuation theorem in nonequilibrium systems.
- Identified the condition for preservation: the feedback information measure must be the same in forward and reverse directions.
Conclusions:
- Feedback control plays a crucial role in modifying and potentially preserving fundamental thermodynamic relations like the detailed fluctuation theorem.
- The findings offer new insights into the statistical mechanics of open systems operating far from equilibrium under feedback.
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