Research

Theory

Importance sampling that turns biased simulations into estimates of the original transition rates.

Energy landscape partitioned into two metastable basins, with success and failure transition paths

Accelerated Langevin Dynamics

A neural-network importance function tilts each Langevin step toward rare transitions, and path weights absorb its errors, so the success-probability estimate stays unbiased for any positive importance function while a branching random walk keeps the weights bounded.

Two-dimensional energy landscape on a grid, with minima A and B, saddle points S1 and S2, and a lattice path from A to B

Accelerated MCMC

A neural network learns a bias potential in log space that steers lattice Monte Carlo through rare transitions, while path reweighting and a branching random walk keep the success-probability estimate unbiased; auxiliary failure and success states keep the formulation robust to grid refinement.

Applications

The methods at work on atomistic and biomolecular rare events.

The unanticipated long-jump mechanism of a Pt adatom on Pt(001): the original adatom (orange) pushes a neighbor (green), which pushes the next atom (blue) up onto the surface as the new adatom

Accelerated Atomistic Simulations

Neural-network importance sampling of Langevin dynamics reproduces reference rates and resolves competing channels, including an unanticipated long jump, for the LJ7 cluster and, in a revised manuscript in preparation, a Pt adatom on Pt(001) and a vacancy in bcc iron.

Alanine dipeptide in the beta/C5 metastable conformation

Agent-Guided Variance Reduction for Protein Kinetics

An agentic search driven by Claude Code selects the weight-control scheme that tames path-weight degeneracy, recovering the alanine dipeptide isomerization rate to within 3–6% of brute-force MD.