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arXiv · 2601.22349

Forward-KL Convergence of Time-Inhomogeneous Langevin Diffusions

Andreas Habring·Martin Zach
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Abstract

Many practical samplers rely on time-dependent drifts -- often induced by annealing or tempering schedules -- to improve exploration and stability. This motivates a unified non-asymptotic analysis of the corresponding Langevin diffusions and their discretizations. We provide a convergence analysis that includes non-asymptotic bounds for the continuous-time diffusion and its Euler--Maruyama discretization in the forward-Kullback--Leibler divergence under a single set of abstract conditions on the time-dependent drift. The results apply to many practically-relevant annealing schemes, including geometric tempering and annealed Langevin sampling. In addition, we provide numerical experiments comparing the annealing schemes covered by our theory in low- and high-dimensional settings.

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Andreas Habring, Martin Zach. 2026-01-29. Forward-KL Convergence of Time-Inhomogeneous Langevin Diffusions. https://arxiv.org/abs/2601.22349

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