# Abide by the Law and Follow the Flow: Conservation Laws for Gradient Flows

arXiv: https://arxiv.org/abs/2307.00144 · HTML: https://mlsanity.com/paper/2307.00144/

## Key facts

- Cited by 45 papers in the map (data through 14 Oct 2026).
- Builds on 21 of its 36 references that are in the map.
- First posted on arXiv 30 Jun 2023.

## Builds on (most cited first, 21 of 21)

- [Understanding deep learning requires rethinking generalization](https://mlsanity.com/paper/1611.03530/) (2016)
- [Reconciling modern machine learning practice and the bias-variance trade-off](https://mlsanity.com/paper/1812.11118/) (2018)
- [Exact solutions to the nonlinear dynamics of learning in deep linear neural networks](https://mlsanity.com/paper/1312.6120/) (2013)
- [The Implicit Bias of Gradient Descent on Separable Data](https://mlsanity.com/paper/1710.10345/) (2017)
- [In Search of the Real Inductive Bias: On the Role of Implicit Regularization in Deep Learning](https://mlsanity.com/paper/1412.6614/) (2014)
- [Implicit Regularization in Matrix Factorization](https://mlsanity.com/paper/1705.09280/) (2017)
- [On the Optimization of Deep Networks: Implicit Acceleration by Overparameterization](https://mlsanity.com/paper/1802.06509/) (2018)
- [Implicit Bias of Gradient Descent for Wide Two-layer Neural Networks Trained with the Logistic Loss](https://mlsanity.com/paper/2002.04486/) (2020)
- [Characterizing Implicit Bias in Terms of Optimization Geometry](https://mlsanity.com/paper/1802.08246/) (2018)
- [A Convergence Analysis of Gradient Descent for Deep Linear Neural Networks](https://mlsanity.com/paper/1810.02281/) (2018)
- [Gradient descent aligns the layers of deep linear networks](https://mlsanity.com/paper/1810.02032/) (2018)
- [Algorithmic Regularization in Learning Deep Homogeneous Models: Layers are Automatically Balanced](https://mlsanity.com/paper/1806.00900/) (2018)
- [Neural Mechanics: Symmetry and Broken Conservation Laws in Deep Learning Dynamics](https://mlsanity.com/paper/2012.04728/) (2020)
- [Implicit Regularization in Deep Learning](https://mlsanity.com/paper/1709.01953/) (2017)
- [On the Implicit Bias of Initialization Shape: Beyond Infinitesimal Mirror Descent](https://mlsanity.com/paper/2102.09769/) (2021)
- [Learning deep linear neural networks: Riemannian gradient flows and convergence to global minimizers](https://mlsanity.com/paper/1910.05505/) (2019)
- [Gradient descent follows the regularization path for general losses](https://mlsanity.com/paper/2006.11226/) (2020)
- [Noether's Learning Dynamics: Role of Symmetry Breaking in Neural Networks](https://mlsanity.com/paper/2105.02716/) (2021)
- [Implicit Bias of Gradient Descent on Reparametrized Models: On Equivalence to Mirror Descent](https://mlsanity.com/paper/2207.04036/) (2022)
- [An Embedding of ReLU Networks and an Analysis of their Identifiability](https://mlsanity.com/paper/2107.09370/) (2021)
- [Noether: The More Things Change, the More Stay the Same](https://mlsanity.com/paper/2104.05508/) (2021)

## Built on by (most cited first, 30 of 45)

- [From Lazy to Rich: Exact Learning Dynamics in Deep Linear Networks](https://mlsanity.com/paper/2409.14623/) (2024)
- [Symmetry in Neural Network Parameter Spaces](https://mlsanity.com/paper/2506.13018/) (2025)
- [There Will Be a Scientific Theory of Deep Learning](https://mlsanity.com/paper/2604.21691/) (2026)
- [Algebra Unveils Deep Learning -- An Invitation to Neuroalgebraic Geometry](https://mlsanity.com/paper/2501.18915/) (2025)
- [Parameter Symmetry and Noise Equilibrium of Stochastic Gradient Descent](https://mlsanity.com/paper/2402.07193/) (2024)
- [Parameter Symmetry Potentially Unifies Deep Learning Theory](https://mlsanity.com/paper/2502.05300/) (2025)
- [Keep the Momentum: Conservation Laws beyond Euclidean Gradient Flows](https://mlsanity.com/paper/2405.12888/) (2024)
- [A path-norm toolkit for modern networks: consequences, promises and challenges](https://mlsanity.com/paper/2310.01225/) (2023)
- [Commute Your Domains: Trajectory Optimality Criterion for Multi-Domain Learning](https://mlsanity.com/paper/2501.15556/) (2025)
- [Position: Solve Layerwise Linear Models First to Understand Neural Dynamical Phenomena (Neural Collapse, Emergence, Lazy/Rich Regime, and Grokking)](https://mlsanity.com/paper/2502.21009/) (2025)
- [Neural Thermodynamics: Entropic Forces in Deep and Universal Representation Learning](https://mlsanity.com/paper/2505.12387/) (2025)
- [Transformative or Conservative? Conservation laws for ResNets and Transformers](https://mlsanity.com/paper/2506.06194/) (2025)
- [Sign-In to the Lottery: Reparameterizing Sparse Training From Scratch](https://mlsanity.com/paper/2504.12801/) (2025)
- [Topology and Geometry of the Learning Space of ReLU Networks: Connectivity and Singularities](https://mlsanity.com/paper/2602.00693/) (2026)
- [Path-conditioned training: a principled way to rescale ReLU neural networks](https://mlsanity.com/paper/2602.19799/) (2026)
- [A Theory of How Pretraining Shapes Inductive Bias in Fine-Tuning](https://mlsanity.com/paper/2602.20062/) (2026)
- [Three Mechanisms of Feature Learning in a Linear Network](https://mlsanity.com/paper/2401.07085/) (2024)
- [Implicit Bias of Policy Gradient in Linear Quadratic Control: Extrapolation to Unseen Initial States](https://mlsanity.com/paper/2402.07875/) (2024)
- [Characterizing the Training Dynamics of Private Fine-tuning with Langevin diffusion](https://mlsanity.com/paper/2402.18905/) (2024)
- [A Rescaling-Invariant Lipschitz Bound Based on Path-Metrics for Modern ReLU Network Parameterizations](https://mlsanity.com/paper/2405.15006/) (2024)
- [Intrinsic training dynamics of deep neural networks](https://mlsanity.com/paper/2508.07370/) (2025)
- [Regularization Implies balancedness in the deep linear network](https://mlsanity.com/paper/2511.01137/) (2025)
- [Never Saddle for Reparameterized Steepest Descent as Mirror Flow](https://mlsanity.com/paper/2603.02064/) (2026)
- [Understanding and inverse design of implicit bias in stochastic learning: a geometric perspective](https://mlsanity.com/paper/2601.06597/) (2026)
- [The Symmetries of Three-Layer ReLU Networks](https://mlsanity.com/paper/2605.18319/) (2026)
- [Implicit Bias of Mirror Flow in Homogeneous Neural Networks: Sparse and Dense Feature Learning](https://mlsanity.com/paper/2605.19458/) (2026)
- [Balanced LoRA: Removing Parameter Invariance to Accelerate Convergence](https://mlsanity.com/paper/2605.31484/) (2026)
- [Muon learns balanced solutions in matrix factorization without slow saddle-to-saddle dynamics](https://mlsanity.com/paper/2606.30509/) (2026)
- [Optimization Insights into Deep Diagonal Linear Networks](https://mlsanity.com/paper/2412.16765/) (2024)
- [Convergence of Shallow ReLU Networks on Weakly Interacting Data](https://mlsanity.com/paper/2502.16977/) (2025)

## Abstract (arXiv)

Understanding the geometric properties of gradient descent dynamics is a key ingredient in deciphering the recent success of very large machine learning models. A striking observation is that trained over-parameterized models retain some properties of the optimization initialization. This "implicit bias" is believed to be responsible for some favorable properties of the trained models and could explain their good generalization properties. The purpose of this article is threefold. First, we rigorously expose the definition and basic properties of "conservation laws", that define quantities conserved during gradient flows of a given model (e.g. of a ReLU network with a given architecture) with any training data and any loss. Then we explain how to find the maximal number of independent conservation laws by performing finite-dimensional algebraic manipulations on the Lie algebra generated by the Jacobian of the model. Finally, we provide algorithms to: a) compute a family of polynomial laws; b) compute the maximal number of (not necessarily polynomial) independent conservation laws. We provide showcase examples that we fully work out theoretically. Besides, applying the two algorithms confirms for a number of ReLU network architectures that all known laws are recovered by the algorithm, and that there are no other independent laws. Such computational tools pave the way to understanding desirable properties of optimization initialization in large machine learning models.
