Ceci n'est pas un committor, yet it samples like one: efficient sampling via approximated committor functions

Fuente: arXiv
Guardado en:
Detalles Bibliográficos
Autores principales: Trizio, Enrico, Rossi, Giorgia, Parrinello, Michele
Formato: Preprint
Publicado: 2026
Materias:
Acceso en línea:
Etiquetas: Agregar Etiqueta
Sin Etiquetas, Sea el primero en etiquetar este registro!
_version_ 1866917299549634560
author Trizio, Enrico
Rossi, Giorgia
Parrinello, Michele
author_facet Trizio, Enrico
Rossi, Giorgia
Parrinello, Michele
contents Atomistic simulations are widely used to investigate reactive processes but are often limited by the rare event problem due to kinetic bottlenecks. We recently introduced an enhanced sampling approach based on the committor function, machine-learned following a variational principle. This method combines a transition-state-oriented bias potential, expressed as a functional of the committor, with a metadynamics-like bias along a committor-based collective variable, enabling uniform exploration of reaction pathways. In its original formulation, the committor is represented by a neural network that takes physical descriptors as input and is trained by minimizing a functional involving gradients with respect to atomic coordinates, which can be computationally demanding in some cases. Here, we propose a simplified learning criterion formulated entirely in the descriptor space, which bypasses the need for explicit and costly coordinate gradients and provides a relaxed upper bound to the original variational principle. Although this approach does not formally target the exact committor, we show that it retains robust sampling performance while significantly reducing computational costs, thus enabling the study of processes that would be practically unfeasible using the original formulation.
format Preprint
id arxiv_https___arxiv_org_abs_2602_23236
institution arXiv
publishDate 2026
record_format arxiv
spellingShingle Ceci n'est pas un committor, yet it samples like one: efficient sampling via approximated committor functions
Trizio, Enrico
Rossi, Giorgia
Parrinello, Michele
Computational Physics
Chemical Physics
Atomistic simulations are widely used to investigate reactive processes but are often limited by the rare event problem due to kinetic bottlenecks. We recently introduced an enhanced sampling approach based on the committor function, machine-learned following a variational principle. This method combines a transition-state-oriented bias potential, expressed as a functional of the committor, with a metadynamics-like bias along a committor-based collective variable, enabling uniform exploration of reaction pathways. In its original formulation, the committor is represented by a neural network that takes physical descriptors as input and is trained by minimizing a functional involving gradients with respect to atomic coordinates, which can be computationally demanding in some cases. Here, we propose a simplified learning criterion formulated entirely in the descriptor space, which bypasses the need for explicit and costly coordinate gradients and provides a relaxed upper bound to the original variational principle. Although this approach does not formally target the exact committor, we show that it retains robust sampling performance while significantly reducing computational costs, thus enabling the study of processes that would be practically unfeasible using the original formulation.
title Ceci n'est pas un committor, yet it samples like one: efficient sampling via approximated committor functions
topic Computational Physics
Chemical Physics
url https://arxiv.org/abs/2602.23236