Neural Non-Equilibrium Hamiltonian Monte Carlo for Corrected Boltzmann Sampling
arXiv:2607.15682
2026
Sampling
2 ideas extracted · analyzed Aug 30, 2026
What the math gives to ML
The paper's transferable contribution is a train-then-correct sampler: a neural finite-time transport can make global moves without requiring the learned dynamics to preserve the target exactly, because the complete proposal path records a computable probability correction. The key asset is path-space correction rather than endpoint-only correction: minimizing expected generalized work trains the proposal toward a reverse-compatible path law, while the same work yields importance weights, free-energy estimates, and an exact independent Metropolis correction. This suggests neural samplers for multimodal targets that can diagnose proposal failure through work variance, effective sample size, and acceptance rather than silently producing biased samples. The most practical transfers are a learned stochastic Hamiltonian bridge and path-level importance or Metropolis correction.
Ideas from this paper
✓✓ Beats tuned baseline
2026
Use the learned path only as a global proposal, then correct complete trajectories rather than endpoints. Exponentiated negative work gives self-normalized importance weights, while the same path ratio gives an independent Metropolis acceptance probability. This turns an imperfect neural sampler into an asymptotically exact sampler whenever forward and reverse path laws overlap.
Useful8/10
Difficulty4/10
Novelty6/10
△ Mechanism confirmed, baseline not beaten
2026
Train a neural finite-time Hamiltonian-style path from an easy base density to a Boltzmann target by minimizing its generalized nonequilibrium work. The work is a path-space log-density ratio, so its mean is a forward KL divergence up to a constant and the endpoint marginal mismatch is bounded by the same quantity. Unlike an uncorrected neural sampler, this produces a global proposal whose bias and overlap can be measured quantitatively.
Useful7/10
Difficulty6/10
Novelty7/10