- Group Name:
- Project A10: Population control of multiple walker simulations via a birth/death process
- URL Slug:
- project-a10-population-control-of-multiple-walker-simulations-via-a-birth-death-process
- Description:
- Conventional Molecular Dynamics (MD) simulations are generally unable to access the long-timescale phenomena that are common in nature. This timescale problem comes from the fact that a typical free energy landscape consists of many metastable states separated by high free energy barriers. If the barriers are much higher than the thermal energy, the system is kinetically trapped in some metastable state and barrier crossings will be rare events on the time scales that we can simulate. One strategy to alleviate this time scale problem is to employ collective variable (CV) based enhanced sampling methods such as metadynamics. A common way to improve the performance of CV-based methods is to employ multiple walkers that share a bias potential and collaboratively sample the free energy landscape. In this way, one reduces the wall-clock time for convergence and makes better usage of modern parallel HPC resources. However, the multiple walkers’ usefulness can be severely diminished due to walkers becoming correlated with each other. Thus, there is a need to develop a population control scheme for walkers to improve performance. In this project, we propose to develop a population control scheme for multiple walker CV-based enhanced sampling based on a recently introduced birth/death accelerated Langevin sampling algorithm (Lu et al., arXiv preprint at arXiv:1905.09863 ). We will adapt this birth/death scheme to atomistic/molecular systems and integrate it into a CV-based multiple walker framework.
- Parent Group: