arXiv Machine Learning

Beyond the Semicircle: Free Diffusion Models with Prescribed Equilibria

arXiv Machine Learning
Aug 10

Free Denoising Diffusion Models

arXiv:2510. 22778v3 Announce Type: replace-cross Abstract: We develop a free-probabilistic framework for denoising diffusion, in which the data is a self-adjoint operator and its law a spectral distribution.

By Swagatam Das
arXiv Machine Learning
Aug 20

Foundations of Diffusion Models in General State Spaces: A Self-Contained Introduction

The article "Foundations of Diffusion Models in General State Spaces: A Self-Contained Introduction" presents a unified primer on diffusion models that applies to both continuous Euclidean data and discrete categorical structures. It develops discrete-time forward noising via Markov kernels and learned reverse dynamics, and connects these to continuous-time limits such as stochastic differential equations in ρ^d and continuous-time Markov chains on finite alphabets, deriving the corresponding Fokker–Planck and master equations. The work also shows how different forward corruption choices—Gaussian processes for continuous spaces and structured categorical transition kernels for discrete spaces—affect reverse dynamics and the evidence lower bound used in training, offering a layered exposition for newcomers, practitioners, and experts alike.

By Vincent Pauline, Tobias H\"oppe, Kirill Neklyudov, Alexander Tong, Stefan Bauer, Andrea Dittadi
Hugging Face Trending Papers
Sep 3

Projected Riemannian Gradient Descent for the Bures-Wasserstein Barycenter: Dimension-Independent Linear Convergence at Unit Step Size

The paper introduces a Projected Riemannian Gradient Descent (RGD) algorithm for computing the Bures‑Wasserstein barycenter of positive definite matrices, achieving dimension‑independent linear convergence at unit step size. It resolves a previous dichotomy by showing that clipping eigenvalues to a fixed interval yields a closed‑form, non‑expansive projection in the BW metric, allowing the algorithm to match the empirical speed of unit‑step RGD while maintaining theoretical guarantees. The method also extends to the invariant matrix projection problem, providing a unified dimension‑independent analysis.

arXiv Machine Learning
Oct 16

Spectral Indistinguishability and Learning-Curve Identifiability in Quadratic Networks

The paper investigates how spectral summaries and scalar learning curves can reveal properties of centered quadratic networks. By constructing analytic positive input densities with Gaussian one- and two-coordinate marginals, the authors show that certain teachers with a nonzero cycle invariant produce distinct factorized loss curves, while others yield identical anchored spectral measures. The study further explores the sample complexity required for noisy scalar loss queries and bounded initialization interventions, identifies conditions under which a single scalar loss curve can recover the initial predictor and teacher spectrum, and provides exact recovery guarantees for fixed dimensions and distinct teacher sums.

By Dekun Yang
arXiv Statistics ML
3d ago

Phases of Muon: When Muon Eclipses SignSGD

The paper analyzes the stochastic optimizer Muon, which orthogonalizes an exponential moving average of minibatch gradients, and compares its behavior to the baseline SignSGD on a high‑dimensional matrix‑valued least squares problem. It derives deterministic dynamics showing Muon’s sensitivity to an effective batch size and its failure to resolve small eigenmodes when whitening is exact and the effective batch is small, while Momentum and finite Newton–Shulz iterations can mitigate this. The study presents a phase diagram in terms of data and target exponents, indicating when Muon or SignSGD is preferable based on covariance spectrum steepness and target loss scaling.

By Elliot Paquette, Noah Marshall, Lucas Benigni, Guangyuan Wang, Atish Agarwala, Courtney Paquette