Enhanced Sampling using Birth-Death Algorithm*

Molecular dynamics simulations face challenges to effectively sample rare event scenarios such as transitions between metastable states that are separated by high-energy barriers, all within a specific time frame. One approach to address this issue is through collective variable -based enhanced sampling methods. These methods involve multiple walkers with the same bias potential to collectively sample the free energy landscape, thereby reducing convergence time. However, when walkers become correlated, it becomes crucial to implement a population control strategy to enhance their performance. In this talk, we introduce one such population control scheme for running multiple walkers in parallel, where we enhance the molecular sampling strategy by augmenting with a birth/death process¹. This process periodically eliminates and duplicates walkers based on a Fokker-Planck Birth-Death equation.

References

1.        Pampel, B., Holbach, S., Hartung, L. & Valsson, O. Sampling rare event energy landscapes via birth-death augmented dynamics. Phys. Rev. E 107, 24141 (2023).