# Universality of high-dimensional scaling limits of stochastic gradient descent

arXiv: https://arxiv.org/abs/2512.13634 · HTML: https://mlsanity.com/paper/2512.13634/

## Key facts

- Cited by 3 papers in the map (data through 14 Oct 2026).
- Builds on 32 of its 54 references that are in the map.
- First posted on arXiv 15 Dec 2025.

## Builds on (most cited first, 30 of 32)

- [Neural Networks can Learn Representations with Gradient Descent](https://mlsanity.com/paper/2206.15144/) (2022)
- [SGD learning on neural networks: leap complexity and saddle-to-saddle dynamics](https://mlsanity.com/paper/2302.11055/) (2023)
- [Online stochastic gradient descent on non-convex losses from high-dimensional inference](https://mlsanity.com/paper/2003.10409/) (2020)
- [The Gaussian equivalence of generative models for learning with shallow neural networks](https://mlsanity.com/paper/2006.14709/) (2020)
- [Dynamics of stochastic gradient descent for two-layer neural networks in the teacher-student setup](https://mlsanity.com/paper/1906.08632/) (2019)
- [Universality of empirical risk minimization](https://mlsanity.com/paper/2202.08832/) (2022)
- [High-dimensional limit theorems for SGD: Effective dynamics and critical scaling](https://mlsanity.com/paper/2206.04030/) (2022)
- [Classifying high-dimensional Gaussian mixtures: Where kernel methods fail and neural networks succeed](https://mlsanity.com/paper/2102.11742/) (2021)
- [Neural Networks Efficiently Learn Low-Dimensional Representations with SGD](https://mlsanity.com/paper/2209.14863/) (2022)
- [Smoothing the Landscape Boosts the Signal for SGD: Optimal Sample Complexity for Learning Single Index Models](https://mlsanity.com/paper/2305.10633/) (2023)
- [On Learning Gaussian Multi-index Models with Gradient Flow](https://mlsanity.com/paper/2310.19793/) (2023)
- [Learning a Single Neuron with Gradient Methods](https://mlsanity.com/paper/2001.05205/) (2020)
- [Phase diagram of Stochastic Gradient Descent in high-dimensional two-layer neural networks](https://mlsanity.com/paper/2202.00293/) (2022)
- [Neural network learns low-dimensional polynomials with SGD near the information-theoretic limit](https://mlsanity.com/paper/2406.01581/) (2024)
- [Computational-Statistical Gaps in Gaussian Single-Index Models](https://mlsanity.com/paper/2403.05529/) (2024)
- [From high-dimensional & mean-field dynamics to dimensionless ODEs: A unifying approach to SGD in two-layers networks](https://mlsanity.com/paper/2302.05882/) (2023)
- [SGD Finds then Tunes Features in Two-Layer Neural Networks with near-Optimal Sample Complexity: A Case Study in the XOR problem](https://mlsanity.com/paper/2309.15111/) (2023)
- [SGD in the Large: Average-case Analysis, Asymptotics, and Stepsize Criticality](https://mlsanity.com/paper/2102.04396/) (2021)
- [Online Stochastic Gradient Descent with Arbitrary Initialization Solves Non-smooth, Non-convex Phase Retrieval](https://mlsanity.com/paper/1910.12837/) (2019)
- [Gradient-Based Feature Learning under Structured Data](https://mlsanity.com/paper/2309.03843/) (2023)
- [Universality laws for Gaussian mixtures in generalized linear models](https://mlsanity.com/paper/2302.08933/) (2023)
- [Hitting the High-Dimensional Notes: An ODE for SGD learning dynamics on GLMs and multi-index models](https://mlsanity.com/paper/2308.08977/) (2023)
- [On Single Index Models beyond Gaussian Data](https://mlsanity.com/paper/2307.15804/) (2023)
- [Universality of Approximate Message Passing Algorithms](https://mlsanity.com/paper/2003.10431/) (2020)
- [Phase Retrieval via Randomized Kaczmarz: Theoretical Guarantees](https://mlsanity.com/paper/1706.09993/) (2017)
- [Scaling Limit: Exact and Tractable Analysis of Online Learning Algorithms with Applications to Regularized Regression and PCA](https://mlsanity.com/paper/1712.04332/) (2017)
- [Learning a Single Neuron for Non-monotonic Activation Functions](https://mlsanity.com/paper/2202.08064/) (2022)
- [Spectral alignment of stochastic gradient descent for high-dimensional classification tasks](https://mlsanity.com/paper/2310.03010/) (2023)
- [Online ICA: Understanding Global Dynamics of Nonconvex Optimization via Diffusion Processes](https://mlsanity.com/paper/1808.09642/) (2018)
- [High-dimensional scaling limits and fluctuations of online least-squares SGD with smooth covariance](https://mlsanity.com/paper/2304.00707/) (2023)

## Built on by (most cited first, 3 of 3)

- [Phases of Muon: When Muon Eclipses SignSGD](https://mlsanity.com/paper/2605.09552/) (2026)
- [The Multiscale Single-Index Model: A Stylized Model for Hierarchical Feature Learning](https://mlsanity.com/paper/2607.03347/) (2026)
- [The Phase Transition in Online PCA Depends on n/dlog(d), not n/d](https://mlsanity.com/paper/2607.23914/) (2026)

## Abstract (arXiv)

We consider statistical tasks in high dimensions whose loss depends on the data only through its projection into a fixed-dimensional subspace spanned by the parameter vectors and certain ground truth vectors. This includes classifying mixture distributions with cross-entropy loss with one and two-layer networks, and learning single and multi-index models with one and two-layer networks. When the data is drawn from an isotropic Gaussian mixture distribution, it is known that the evolution of a finite family of summary statistics under stochastic gradient descent converges to an autonomous ordinary differential equation (ODE), as the dimension and sample size go to ∞ and the step size goes to 0 commensurately. Our main result is that these ODE limits are universal in that this limit is the same whenever the data is drawn from mixtures of arbitrary product distributions whose first two moments match the corresponding Gaussian distribution, provided the initialization and ground truth vectors are coordinate-delocalized. We complement this by proving two corresponding non-universality results. We provide a simple example where the ODE limits are non-universal if the initialization is coordinate aligned. We also show that the stochastic differential equation limits arising as fluctuations of the summary statistics around their ODE's fixed points are not universal.
