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arXiv · 2410.09805

Inference of non-exponential kinetics through stochastic resetting

Abstract

We present an inference scheme of long timescale, non-exponential kinetics from Molecular Dynamics simulations accelerated by stochastic resetting. Standard simulations provide valuable insight into chemical processes but are limited to timescales shorter than $\sim 1 \mu s$. Slower processes require the use of enhanced sampling methods to expedite them, and inference schemes to obtain the unbiased kinetics. However, most kinetics inference schemes assume an underlying exponential first-passage time distribution and are inappropriate for other distributions, e.g., with a power-law decay. We propose an inference scheme that is designed for such cases, based on simulations enhanced by stochastic resetting. We show that resetting promotes enhanced sampling of the first-passage time distribution at short timescales, but often also provides sufficient information to estimate the long-time asymptotics, which allows the kinetics inference. We apply our method to a model system and a short peptide in an explicit solvent, successfully estimating the unbiased mean first-passage time while accelerating the sampling by more than an order of magnitude.

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Ofir Blumer, Shlomi Reuveni, Barak Hirshberg. 2024-10-13. Inference of non-exponential kinetics through stochastic resetting. https://arxiv.org/abs/2410.09805

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