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Updated: Sep 30, 2025

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Published on: December 4, 2017
Learning nonequilibrium control forces to characterize dynamical phase transitions
Jiawei Yan1, Hugo Touchette2, Grant M Rotskoff1
1Department of Chemistry, Stanford University, Stanford, California 94305, USA.
This study introduces a machine learning algorithm to efficiently sample rare trajectories in complex systems. The new method scales well for large systems and remains effective near dynamical phase transitions.
Area of Science:
- Statistical Physics
- Complex Systems
- Machine Learning
Background:
- Studying nonequilibrium systems requires analyzing rare dynamical fluctuations.
- Existing methods for sampling rare trajectories struggle with scalability, particularly near phase transitions.
Purpose of the Study:
- To develop a scalable machine learning algorithm for sampling rare trajectories.
- To estimate large deviation functions in systems with many interacting particles.
Main Methods:
- Utilizing deep neural networks for flexible function representation.
- Implementing importance sampling in trajectory space.
- Applying stochastic optimal control theory with a many-body control force.
Main Results:
- The proposed algorithm demonstrates scalability to systems with hundreds of interacting particles.
- The method proves robust even at dynamical phase transitions.
Conclusions:
- This machine learning approach offers a significant advancement in studying nonequilibrium pattern formation.
- The algorithm provides a powerful tool for analyzing complex systems where rare events are critical.
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