# Global Convergence of Over-parameterized Deep Equilibrium Models

arXiv: https://arxiv.org/abs/2205.13814 · HTML: https://mlsanity.com/paper/2205.13814/

## Key facts

- Cited by 10 papers in the map (data through 14 Oct 2026).
- Builds on 25 of its 34 references that are in the map.
- First posted on arXiv 27 May 2022.

## Builds on (most cited first, 25 of 25)

- [A Convergence Theory for Deep Learning via Over-Parameterization](https://mlsanity.com/paper/1811.03962/) (2018)
- [Gradient Descent Provably Optimizes Over-parameterized Neural Networks](https://mlsanity.com/paper/1810.02054/) (2018)
- [Deep Equilibrium Models](https://mlsanity.com/paper/1909.01377/) (2019)
- [Gradient Descent Finds Global Minima of Deep Neural Networks](https://mlsanity.com/paper/1811.03804/) (2018)
- [On Exact Computation with an Infinitely Wide Neural Net](https://mlsanity.com/paper/1904.11955/) (2019)
- [Learning Overparameterized Neural Networks via Stochastic Gradient Descent on Structured Data](https://mlsanity.com/paper/1808.01204/) (2018)
- [Towards moderate overparameterization: global convergence guarantees for training shallow neural networks](https://mlsanity.com/paper/1902.04674/) (2019)
- [Tensor Programs I: Wide Feedforward or Recurrent Neural Networks of Any Architecture are Gaussian Processes](https://mlsanity.com/paper/1910.12478/) (2019)
- [Multiscale Deep Equilibrium Models](https://mlsanity.com/paper/2006.08656/) (2020)
- [Tensor Programs II: Neural Tangent Kernel for Any Architecture](https://mlsanity.com/paper/2006.14548/) (2020)
- [Stochastic Gradient Descent Optimizes Over-parameterized Deep ReLU Networks](https://mlsanity.com/paper/1811.08888/) (2018)
- [Toward Deeper Understanding of Neural Networks: The Power of Initialization and a Dual View on Expressivity](https://mlsanity.com/paper/1602.05897/) (2016)
- [Deep Equilibrium Architectures for Inverse Problems in Imaging](https://mlsanity.com/paper/2102.07944/) (2021)
- [Implicit Deep Learning](https://mlsanity.com/paper/1908.06315/) (2019)
- [An Improved Analysis of Training Over-parameterized Deep Neural Networks](https://mlsanity.com/paper/1906.04688/) (2019)
- [Monotone operator equilibrium networks](https://mlsanity.com/paper/2006.08591/) (2020)
- [On the Convergence Rate of Training Recurrent Neural Networks](https://mlsanity.com/paper/1810.12065/) (2018)
- [Global Convergence of Deep Networks with One Wide Layer Followed by Pyramidal Topology](https://mlsanity.com/paper/2002.07867/) (2020)
- [Tensor Programs III: Neural Matrix Laws](https://mlsanity.com/paper/2009.10685/) (2020)
- [Lipschitz Bounded Equilibrium Networks](https://mlsanity.com/paper/2010.01732/) (2020)
- [On the Proof of Global Convergence of Gradient Descent for Deep ReLU Networks with Linear Widths](https://mlsanity.com/paper/2101.09612/) (2021)
- [On the Theory of Implicit Deep Learning: Global Convergence with Implicit Layers](https://mlsanity.com/paper/2102.07346/) (2021)
- [A global convergence theory for deep ReLU implicit networks via over-parameterization](https://mlsanity.com/paper/2110.05645/) (2021)
- [On the Provable Generalization of Recurrent Neural Networks](https://mlsanity.com/paper/2109.14142/) (2021)
- [Gradient Descent Optimizes Infinite-Depth ReLU Implicit Networks with Linear Widths](https://mlsanity.com/paper/2205.07463/) (2022)

## Built on by (most cited first, 10 of 10)

- [Deep Equilibrium Approaches to Diffusion Models](https://mlsanity.com/paper/2210.12867/) (2022)
- [Deep Equilibrium Models are Almost Equivalent to Not-so-deep Explicit Models for High-dimensional Gaussian Mixtures](https://mlsanity.com/paper/2402.02697/) (2024)
- [Global Convergence Rate of Deep Equilibrium Models with General Activations](https://mlsanity.com/paper/2302.05797/) (2023)
- [IGNN-Solver: A Graph Neural Solver for Implicit Graph Neural Networks](https://mlsanity.com/paper/2410.08524/) (2024)
- [Understanding Representation of Deep Equilibrium Models from Neural Collapse Perspective](https://mlsanity.com/paper/2410.23391/) (2024)
- [Certified Robustness for Deep Equilibrium Models via Serialized Random Smoothing](https://mlsanity.com/paper/2411.00899/) (2024)
- [Consistency Deep Equilibrium Models](https://mlsanity.com/paper/2602.03024/) (2026)
- [Lipschitz Multiscale Deep Equilibrium Models: A Theoretically Guaranteed and Accelerated Approach](https://mlsanity.com/paper/2602.03297/) (2026)
- [On the Equivalence between Implicit and Explicit Neural Networks: A High-dimensional Viewpoint](https://mlsanity.com/paper/2308.16425/) (2023)
- [Certified Inference and Training for Deep Equilibrium Networks: A Continuation Framework with Polynomial Complexity Guarantees](https://mlsanity.com/paper/2609.16485/) (2026)

## Abstract (arXiv)

A deep equilibrium model (DEQ) is implicitly defined through an equilibrium point of an infinite-depth weight-tied model with an input-injection. Instead of infinite computations, it solves an equilibrium point directly with root-finding and computes gradients with implicit differentiation. The training dynamics of over-parameterized DEQs are investigated in this study. By supposing a condition on the initial equilibrium point, we show that the unique equilibrium point always exists during the training process, and the gradient descent is proved to converge to a globally optimal solution at a linear convergence rate for the quadratic loss function. In order to show that the required initial condition is satisfied via mild over-parameterization, we perform a fine-grained analysis on random DEQs. We propose a novel probabilistic framework to overcome the technical difficulty in the non-asymptotic analysis of infinite-depth weight-tied models.
