# Normalization Layers Are All That Sharpness-Aware Minimization Needs

arXiv: https://arxiv.org/abs/2306.04226 · HTML: https://mlsanity.com/paper/2306.04226/

## Key facts

- Cited by 27 papers in the map (data through 14 Oct 2026).
- Builds on 54 of its 61 references that are in the map.
- First posted on arXiv 7 Jun 2023.

## Builds on (most cited first, 30 of 54)

- [Attention Is All You Need](https://mlsanity.com/paper/1706.03762/) (2017)
- [Deep Residual Learning for Image Recognition](https://mlsanity.com/paper/1512.03385/) (2015)
- [An Image is Worth 16x16 Words: Transformers for Image Recognition at Scale](https://mlsanity.com/paper/2010.11929/) (2020)
- [Very Deep Convolutional Networks for Large-Scale Image Recognition](https://mlsanity.com/paper/1409.1556/) (2014)
- [Batch Normalization: Accelerating Deep Network Training by Reducing Internal Covariate Shift](https://mlsanity.com/paper/1502.03167/) (2015)
- [Densely Connected Convolutional Networks](https://mlsanity.com/paper/1608.06993/) (2016)
- [Layer Normalization](https://mlsanity.com/paper/1607.06450/) (2016)
- [Intriguing properties of neural networks](https://mlsanity.com/paper/1312.6199/) (2013)
- [Wide Residual Networks](https://mlsanity.com/paper/1605.07146/) (2016)
- [Aggregated Residual Transformations for Deep Neural Networks](https://mlsanity.com/paper/1611.05431/) (2016)
- [Reliable evaluation of adversarial robustness with an ensemble of diverse parameter-free attacks](https://mlsanity.com/paper/2003.01690/) (2020)
- [Sharpness-Aware Minimization for Efficiently Improving Generalization](https://mlsanity.com/paper/2010.01412/) (2020)
- [On Large-Batch Training for Deep Learning: Generalization Gap and Sharp Minima](https://mlsanity.com/paper/1609.04836/) (2016)
- [How to train your ViT? Data, Augmentation, and Regularization in Vision Transformers](https://mlsanity.com/paper/2106.10270/) (2021)
- [Computing Nonvacuous Generalization Bounds for Deep (Stochastic) Neural Networks with Many More Parameters than Training Data](https://mlsanity.com/paper/1703.11008/) (2017)
- [Fantastic Generalization Measures and Where to Find Them](https://mlsanity.com/paper/1912.02178/) (2019)
- [Sharp Minima Can Generalize For Deep Nets](https://mlsanity.com/paper/1703.04933/) (2017)
- [Symbolic Discovery of Optimization Algorithms](https://mlsanity.com/paper/2302.06675/) (2023)
- [High-Performance Large-Scale Image Recognition Without Normalization](https://mlsanity.com/paper/2102.06171/) (2021)
- [How Does Batch Normalization Help Optimization?](https://mlsanity.com/paper/1805.11604/) (2018)
- [ASAM: Adaptive Sharpness-Aware Minimization for Scale-Invariant Learning of Deep Neural Networks](https://mlsanity.com/paper/2102.11600/) (2021)
- [PyHessian: Neural Networks Through the Lens of the Hessian](https://mlsanity.com/paper/1912.07145/) (2019)
- [Train longer, generalize better: closing the generalization gap in large batch training of neural networks](https://mlsanity.com/paper/1705.08741/) (2017)
- [When Vision Transformers Outperform ResNets without Pre-training or Strong Data Augmentations](https://mlsanity.com/paper/2106.01548/) (2021)
- [Understanding and Improving Layer Normalization](https://mlsanity.com/paper/1911.07013/) (2019)
- [Fixup Initialization: Residual Learning Without Normalization](https://mlsanity.com/paper/1901.09321/) (2019)
- [Surrogate Gap Minimization Improves Sharpness-Aware Training](https://mlsanity.com/paper/2203.08065/) (2022)
- [Understanding Batch Normalization](https://mlsanity.com/paper/1806.02375/) (2018)
- [Towards Understanding Sharpness-Aware Minimization](https://mlsanity.com/paper/2206.06232/) (2022)
- [Efficient Sharpness-aware Minimization for Improved Training of Neural Networks](https://mlsanity.com/paper/2110.03141/) (2021)

## Built on by (most cited first, 27 of 27)

- [Transformers without Normalization](https://mlsanity.com/paper/2503.10622/) (2025)
- [Locally Estimated Global Perturbations are Better than Local Perturbations for Federated Sharpness-aware Minimization](https://mlsanity.com/paper/2405.18890/) (2024)
- [On the Duality Between Sharpness-Aware Minimization and Adversarial Training](https://mlsanity.com/paper/2402.15152/) (2024)
- [Sharpness-Aware Minimization Efficiently Selects Flatter Minima Late in Training](https://mlsanity.com/paper/2410.10373/) (2024)
- [Layer-wise Linear Mode Connectivity](https://mlsanity.com/paper/2307.06966/) (2023)
- [Momentum-SAM: Sharpness Aware Minimization without Computational Overhead](https://mlsanity.com/paper/2401.12033/) (2024)
- [Improving Generalization and Convergence by Enhancing Implicit Regularization](https://mlsanity.com/paper/2405.20763/) (2024)
- [QT-DoG: Quantization-aware Training for Domain Generalization](https://mlsanity.com/paper/2410.06020/) (2024)
- [Adaptive Preconditioners Trigger Loss Spikes in Adam](https://mlsanity.com/paper/2506.04805/) (2025)
- [Stronger Normalization-Free Transformers](https://mlsanity.com/paper/2512.10938/) (2025)
- [SAMPa: Sharpness-aware Minimization Parallelized](https://mlsanity.com/paper/2410.10683/) (2024)
- [Adapter Naturally Serves as Decoupler for Cross-Domain Few-Shot Semantic Segmentation](https://mlsanity.com/paper/2506.07376/) (2025)
- [On Surprising Effectiveness of Masking Updates in Adaptive Optimizers](https://mlsanity.com/paper/2602.15322/) (2026)
- [Tilted Sharpness-Aware Minimization](https://mlsanity.com/paper/2410.22656/) (2024)
- [Analyzing limits for in-context learning](https://mlsanity.com/paper/2502.03503/) (2025)
- [Towards Understanding the Role of Sharpness-Aware Minimization Algorithms for Out-of-Distribution Generalization](https://mlsanity.com/paper/2412.05169/) (2024)
- [Can Optimization Trajectories Explain Multi-Task Transfer?](https://mlsanity.com/paper/2408.14677/) (2024)
- [Asynchronous Sharpness-Aware Minimization For Fast and Accurate Deep Learning](https://mlsanity.com/paper/2503.11147/) (2025)
- [Do Flat Minima Improve Sparse Novel View Synthesis?](https://mlsanity.com/paper/2511.17918/) (2025)
- [Forget Sharpness: Perturbed Forgetting of Model Biases Within SAM Dynamics](https://mlsanity.com/paper/2406.06700/) (2024)
- [Equivariant Test-Time Training with Operator Sketching for Imaging Inverse Problems](https://mlsanity.com/paper/2411.05771/) (2024)
- [Unpacking the Implicit Norm Dynamics of Sharpness-Aware Minimization in Tensorized Models](https://mlsanity.com/paper/2508.10435/) (2025)
- [Sharpness-Aware Minimization Can Hallucinate Minimizers](https://mlsanity.com/paper/2509.21818/) (2025)
- [The Hidden Power of Normalization Layers in Neural Networks: Exponential Capacity Control](https://mlsanity.com/paper/2511.00958/) (2025)
- [Stable Coresets via Posterior Sampling: Aligning Induced and Full Loss Landscapes](https://mlsanity.com/paper/2511.17399/) (2025)
- [Gradient-Energy Guided Block-Wise Perturbations for Sharpness-Aware Minimization](https://mlsanity.com/paper/2607.18306/) (2026)
- [SandwichQuant: Which Parameters Matter Before and After Quantization?](https://mlsanity.com/paper/2608.24173/) (2026)

## Abstract (arXiv)

Sharpness-aware minimization (SAM) was proposed to reduce sharpness of minima and has been shown to enhance generalization performance in various settings. In this work we show that perturbing only the affine normalization parameters (typically comprising 0.1% of the total parameters) in the adversarial step of SAM can outperform perturbing all of the parameters.This finding generalizes to different SAM variants and both ResNet (Batch Normalization) and Vision Transformer (Layer Normalization) architectures. We consider alternative sparse perturbation approaches and find that these do not achieve similar performance enhancement at such extreme sparsity levels, showing that this behaviour is unique to the normalization layers. Although our findings reaffirm the effectiveness of SAM in improving generalization performance, they cast doubt on whether this is solely caused by reduced sharpness.
