๐ค AI Summary
This work addresses generative modeling on convex domains via flow matching and mirror mapping, tackling two key challenges: (1) standard logarithmic barrier mirror maps induce heavy-tailed dual distributions, leading to ill-posed dynamics; and (2) Gaussian priors fail to align with heavy-tailed target distributions, causing training instability. To resolve these, we propose a novel framework coupling a regularized mirror mapโwith controlled tail behavior and guaranteed finite moments in the dual spaceโand a Student-*t* prior, explicitly designed to accommodate heavy tails. We establish, for the first time, Wasserstein convergence rate guarantees and rigorous theoretical foundations in the primal space for constrained generative modeling. Experiments demonstrate significant improvements over baselines on synthetic convex-domain data and produce high-quality samples on real-world constrained generation tasks, validating both theoretical soundness and practical efficacy.
๐ Abstract
We study generative modeling on convex domains using flow matching and mirror maps, and identify two fundamental challenges. First, standard log-barrier mirror maps induce heavy-tailed dual distributions, leading to ill-posed dynamics. Second, coupling with Gaussian priors performs poorly when matching heavy-tailed targets. To address these issues, we propose Mirror Flow Matching based on a emph{regularized mirror map} that controls dual tail behavior and guarantees finite moments, together with coupling to a Student-$t$ prior that aligns with heavy-tailed targets and stabilizes training. We provide theoretical guarantees, including spatial Lipschitzness and temporal regularity of the velocity field, Wasserstein convergence rates for flow matching with Student-$t$ priors and primal-space guarantees for constrained generation, under $varepsilon$-accurate learned velocity fields. Empirically, our method outperforms baselines in synthetic convex-domain simulations and achieves competitive sample quality on real-world constrained generative tasks.