Learning interpretable dynamics of stochastic complex systems from experimental data
Ting-Ting Gao1,2, Baruch Barzel3,4, Gang Yan5,6
1MOE Key Laboratory of Advanced Micro-Structured Materials, and School of Physical Science and Engineering, Tongji University, Shanghai, P. R. China.
Nature Communications
|July 17, 2024
Summary
We developed a Langevin graph network to infer hidden stochastic differential equations in complex systems. This method accurately models bird flocking and tau pathology spread in brains, enabling new control applications.
Area of Science:
- Complex Systems
- Network Science
- Computational Neuroscience
Background:
- Complex systems with numerous interacting components exhibit inherent randomness, best modeled by stochastic differential equations.
- Inferring these underlying stochastic differential equations from observational data is a significant challenge in analyzing complex systems.
- Existing methods struggle to accurately capture the dynamics of networked systems from empirical data.
Purpose of the Study:
- To introduce a novel Langevin graph network approach for learning hidden stochastic differential equations in complex networked systems.
- To validate the efficacy of the proposed method against state-of-the-art techniques.
- To apply the approach to real-world systems, including biological and physical phenomena.
Main Methods:
- Development of a Langevin graph network architecture designed to infer stochastic differential equations.
- Application of the network to simulated and real-world complex systems.
- Comparative analysis against five leading inference methods.
Main Results:
- The Langevin graph network approach significantly outperformed five state-of-the-art methods in inferring stochastic differential equations.
- Inferred equations for bird flock movement closely matched the second-order Vicsek model, validating its applicability to physical systems.
- The method successfully uncovered the governing equation for tau pathology diffusion in mouse brains, allowing for early prediction and revealing distinct dynamics.
Conclusions:
- The Langevin graph network provides a powerful tool for learning interpretable stochastic dynamics in complex systems.
- This approach offers unprecedented insights into phenomena such as flocking behavior and neurodegenerative disease progression.
- The findings open new possibilities for the control and management of complex networked systems.
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