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Updated: May 23, 2026
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Published on: April 19, 2021
Nonequilibrium thermodynamics of feedback control
Takahiro Sagawa1, Masahito Ueda
1Hakubi Center, Kyoto University, Kyoto 606-8302, Japan.
Summary
We developed a general theory for feedback control in stochastic thermodynamics, generalizing key equalities like the fluctuation theorem. This framework accounts for multiple measurements and heat baths, enhancing our understanding of information and control efficacy.
Area of Science:
- Thermodynamics
- Statistical Mechanics
- Information Theory
Background:
- Stochastic thermodynamics studies energy transformations in small systems.
- Nonequilibrium equalities provide fundamental insights into these processes.
- Feedback control introduces new dynamics by using measurement information.
Purpose of the Study:
- To develop a general theory of feedback control for classical stochastic thermodynamic systems.
- To generalize fundamental nonequilibrium equalities under feedback control with multiple measurements.
- To investigate the role of measurement information and control efficacy in thermodynamic processes.
Main Methods:
- Formulation of a general feedback control theory for stochastic thermodynamics.
- Generalization of fluctuation theorems and Jarzynski equality.
- Analysis of systems with multiple heat baths and general measurement schemes.
Main Results:
- Established a generalized theory for feedback control in stochastic thermodynamics.
- Derived generalized nonequilibrium equalities incorporating information and control terms.
- Demonstrated the applicability of the derived equalities to a generalized Szilard engine and a feedback-controlled ratchet.
Conclusions:
- Feedback control significantly impacts stochastic thermodynamic equalities.
- The generalized equalities provide a framework for analyzing information-driven thermodynamic processes.
- The theory is applicable to various nanoscale thermodynamic engines and devices.
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