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Sampling Efficiency of Transverse Forces in Dense Liquids
Federico Ghimenti1, Ludovic Berthier2,3, Grzegorz Szamel4
1Laboratoire Matière et Systèmes Complexes (MSC), Université Paris Cité et CNRS (UMR 7057), 75013 Paris, France.
Physical Review Letters
|January 5, 2024
Summary
Using nonequilibrium forces can accelerate sampling of the Boltzmann distribution in dense liquids. This speedup depends non-monotonically on temperature and decreases in glassy systems, revealing insights into sampling efficiency.
Area of Science:
- Statistical Mechanics
- Computational Physics
- Soft Matter Physics
Background:
- Sampling the Boltzmann distribution is crucial for molecular simulations.
- Nonequilibrium methods can accelerate sampling but their efficiency varies.
- Forces transverse to energy gradients offer a potential route for faster sampling.
Purpose of the Study:
- To investigate the efficiency of transverse forces for sampling in dense liquids.
- To understand how temperature and system's glassy nature affect sampling speedup.
- To characterize the relationship between distance from equilibrium and sampling efficiency.
Main Methods:
- Brownian dynamics simulations.
- Exact infinite-dimensional calculations.
- Mode-coupling approximations.
Main Results:
- Sampling speedup shows non-monotonic dependence on temperature.
- Efficiency of transverse forces decreases as systems become more glassy.
- Odd transport coefficients quantify the interplay between equilibrium distance and efficiency.
Conclusions:
- Transverse forces offer a tunable method for accelerating Boltzmann distribution sampling.
- Temperature and glassiness are critical factors governing the effectiveness of nonequilibrium sampling strategies.
- Understanding these factors is key to optimizing simulation efficiency in complex systems.
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