# Natural gradient descent with momentum

arXiv: https://arxiv.org/abs/2604.15554 · HTML: https://mlsanity.com/paper/2604.15554/

## Key facts

- Cited by 2 papers in the map (data through 14 Oct 2026).
- Builds on 18 of its 30 references that are in the map.
- First posted on arXiv 16 Apr 2026.

## Builds on (most cited first, 18 of 18)

- [Optimizing Neural Networks with Kronecker-factored Approximate Curvature](https://mlsanity.com/paper/1503.05671/) (2015)
- [New insights and perspectives on the natural gradient method](https://mlsanity.com/paper/1412.1193/) (2014)
- [A Differential Equation for Modeling Nesterov's Accelerated Gradient Method: Theory and Insights](https://mlsanity.com/paper/1503.01243/) (2015)
- [Gauss-Newton Natural Gradient Descent for Physics-Informed Computational Fluid Dynamics](https://mlsanity.com/paper/2402.10680/) (2024)
- [A Kaczmarz-inspired approach to accelerate the optimization of neural network wavefunctions](https://mlsanity.com/paper/2401.10190/) (2024)
- [From Nesterov's Estimate Sequence to Riemannian Acceleration](https://mlsanity.com/paper/2001.08876/) (2020)
- [First-order optimization algorithms via inertial systems with Hessian driven damping](https://mlsanity.com/paper/1907.10536/) (2019)
- [Position: Optimization in SciML Should Employ the Function Space Geometry](https://mlsanity.com/paper/2402.07318/) (2024)
- [Improving Energy Natural Gradient Descent through Woodbury, Momentum, and Randomization](https://mlsanity.com/paper/2505.12149/) (2025)
- [Towards Riemannian Accelerated Gradient Methods](https://mlsanity.com/paper/1806.02812/) (2018)
- [Achieving High Accuracy with PINNs via Energy Natural Gradients](https://mlsanity.com/paper/2302.13163/) (2023)
- [From the Ravine method to the Nesterov method and vice versa: a dynamical system perspective](https://mlsanity.com/paper/2201.11643/) (2022)
- [ANaGRAM: A Natural Gradient Relative to Adapted Model for efficient PINNs learning](https://mlsanity.com/paper/2412.10782/) (2024)
- [Optimal sampling for least-squares approximation](https://mlsanity.com/paper/2409.02342/) (2024)
- [Generalizing Adam to Manifolds for Efficiently Training Transformers](https://mlsanity.com/paper/2305.16901/) (2023)
- [Optimal sampling for stochastic and natural gradient descent](https://mlsanity.com/paper/2402.03113/) (2024)
- [Accelerated Natural Gradient Method for Parametric Manifold Optimization](https://mlsanity.com/paper/2504.05753/) (2025)
- [Weighted least-squares approximation with determinantal point processes and generalized volume sampling](https://mlsanity.com/paper/2312.14057/) (2023)

## Built on by (most cited first, 2 of 2)

- [Dirac-Frenkel dynamics with inertia for nonlinearly parametrized solutions of evolution problems](https://mlsanity.com/paper/2606.24769/) (2026)
- [Beyond PINNs: A Unified Gauss--Newton and Petrov--Galerkin Framework for Neural and Hybrid PDE Solvers](https://mlsanity.com/paper/2609.20641/) (2026)

## Abstract (arXiv)

We consider the problem of approximating a function by an element of a nonlinear manifold which admits a differentiable parametrization, typical examples being neural networks with differentiable activation functions or tensor networks. Natural gradient descent (NGD) for the optimization of a loss function can be seen as a preconditioned gradient descent where updates in the parameter space are driven by a functional perspective. In a spirit similar to Newton's method, a NGD step uses, instead of the Hessian, the Gram matrix of the generating system of the tangent space to the approximation manifold at the current iterate, with respect to a suitable metric. This corresponds to a locally optimal update in function space, following a projected gradient onto the tangent space to the manifold. Still, both gradient and natural gradient descent methods get stuck in local minima. Furthermore, when the model class is a nonlinear manifold or the loss function is not ideally conditioned (e.g., the KL-divergence for density estimation, or a norm of the residual of a partial differential equation in physics informed learning), even the natural gradient might yield non-optimal directions at each step. This work introduces a natural version of classical inertial dynamic methods like Heavy-Ball or Nesterov and show how it can improve the learning process when working with nonlinear model classes.
