Why Transformers Need Adam: A Hessian Perspective
Not on the map. Why?
Abstract (arXiv)
SGD performs worse than Adam by a significant margin on Transformers, but the reason remains unclear. In this work, we provide an explanation through the lens of Hessian: (i) Transformers are "heterogeneous": the Hessian spectrum across parameter blocks vary dramatically, a phenomenon we call "block heterogeneity"; (ii) Heterogeneity hampers SGD: SGD performs worse than Adam on problems with block heterogeneity. To validate (i) and (ii), we check various Transformers, CNNs, MLPs, and quadratic problems, and find that SGD can perform on par with Adam on problems without block heterogeneity, but performs worse than Adam when the heterogeneity exists. Our initial theoretical analysis indicates that SGD performs worse because it applies one single learning rate to all blocks, which cannot handle the heterogeneity among blocks. This limitation could be ameliorated if we use coordinate-wise learning rates, as designed in Adam.
Key facts. Cited by 123 papers in the map (data through 7 Oct 2026). Builds on 74 of its 114 references that are in the map. First posted on arXiv 26 Feb 2024.
Builds on
74 of 114 references.
References · 74
- 2017Attention Is All You Needcited by 59,932
- 2015Deep Residual Learning for Image Recognitioncited by 51,809
- 2018BERT: Pre-training of Deep Bidirectional Transformers for Language Understandingcited by 40,204
- 2020An Image is Worth 16x16 Words: Transformers for Image Recognition at Scalecited by 29,915
- 2023GPT-4 Technical Reportcited by 18,132
- 2014Very Deep Convolutional Networks for Large-Scale Image Recognitioncited by 15,267
- 2020Scaling Laws for Neural Language Modelscited by 6,411
- 2022PaLM: Scaling Language Modeling with Pathwayscited by 5,304
- 2023Mamba: Linear-Time Sequence Modeling with Selective State Spacescited by 4,616
- 2022FlashAttention: Fast and Memory-Efficient Exact Attention with IO-Awarenesscited by 3,611
- 2022OPT: Open Pre-trained Transformer Language Modelscited by 3,464
- 2021MLP-Mixer: An all-MLP Architecture for Visioncited by 1,441
38 more
- 2020On Layer Normalization in the Transformer Architecturecited by 906
- 2022GLM-130B: An Open Bilingual Pre-trained Modelcited by 837
- 2019On the Convergence of Adam and Beyondcited by 834
- 2015Optimizing Neural Networks with Kronecker-factored Approximate Curvaturecited by 776
- 2019On the Variance of the Adaptive Learning Rate and Beyondcited by 763
- 2023Scaling Vision Transformers to 22 Billion Parameterscited by 690
- 2023Baichuan 2: Open Large-scale Language Modelscited by 664
- 2018signSGD: Compressed Optimisation for Non-Convex Problemscited by 561
- 2021Attention is Not All You Need: Pure Attention Loses Rank Doubly Exponentially with Depthcited by 411
- 2021Early Convolutions Help Transformers See Bettercited by 395
- 2016Entropy-SGD: Biasing Gradient Descent Into Wide Valleyscited by 357
- 2023Fine-Tuning Language Models with Just Forward Passescited by 337
- 2019Why gradient clipping accelerates training: A theoretical justification for adaptivitycited by 335
- 2019Learning Deep Transformer Models for Machine Translationcited by 309
- 2019PyHessian: Neural Networks Through the Lens of the Hessiancited by 291
- 2019An Investigation into Neural Net Optimization via Hessian Eigenvalue Densitycited by 289
- 2017Empirical Analysis of the Hessian of Over-Parametrized Neural Networkscited by 283
- 2022Tensor Programs V: Tuning Large Neural Networks via Zero-Shot Hyperparameter Transfercited by 272
- 2020ReZero is All You Need: Fast Convergence at Large Depthcited by 260
- 2023Sophia: A Scalable Stochastic Second-order Optimizer for Language Model Pre-trainingcited by 260
- 2020Understanding the Difficulty of Training Transformerscited by 210
- 2018Gradient Descent Happens in a Tiny Subspacecited by 208
- 2023Small-scale proxies for large-scale Transformer training instabilitiescited by 182
- 2019Adaptive Gradient Methods with Dynamic Bound of Learning Ratecited by 181
- 2022DeepNet: Scaling Transformers to 1,000 Layerscited by 176
- 2018On the Convergence of A Class of Adam-Type Algorithms for Non-Convex Optimizationcited by 173
- 2020A Simple Convergence Proof of Adam and Adagradcited by 169
- 2016Eigenvalues of the Hessian in Deep Learning: Singularity and Beyondcited by 156
- 2023Stabilizing Transformer Training by Preventing Attention Entropy Collapsecited by 154
- 2019Transformers without Tears: Improving the Normalization of Self-Attentioncited by 153
- 2022Signal Propagation in Transformers: Theoretical Perspectives and the Role of Rank Collapsecited by 136
- 2023Full Parameter Fine-tuning for Large Language Models with Limited Resourcescited by 134
- 2018A Sufficient Condition for Convergences of Adam and RMSPropcited by 124
- 2019Which Algorithmic Choices Matter at Which Batch Sizes? Insights From a Noisy Quadratic Modelcited by 116
- 2023Noise Is Not the Main Factor Behind the Gap Between SGD and Adam on Transformers, but Sign Descent Might Becited by 114
- 2022Adam Can Converge Without Any Modification On Update Rulescited by 112
- 2018The Best of Both Worlds: Combining Recent Advances in Neural Machine Translationcited by 101
- 2023Convergence of Adam Under Relaxed Assumptionscited by 97
50 most cited of 74 All 74 (JSON)
Built on by
Citing papers per year: 2024: 25; 2025: 40; 2026: 58.
123 papers.
Sort:
By area:
- 2024Adam-mini: Use Fewer Learning Rates To Gain Morecited by 134
- 2024Heavy-Tailed Class Imbalance and Why Adam Outperforms Gradient Descent on Language Modelscited by 78
- 2024Preserving Diversity in Supervised Fine-Tuning of Large Language Modelscited by 68
- 2025ASGO: Adaptive Structured Gradient Optimizationcited by 55
- 2024APOLLO: SGD-like Memory, AdamW-level Performancecited by 50
- 2024Deconstructing What Makes a Good Optimizer for Language Modelscited by 40
- 2025In Search of Adam's Secret Saucecited by 40
- 2025Muon Outperforms Adam in Tail-End Associative Memory Learningcited by 38
- 2025Small Batch Size Training for Language Models: When Vanilla SGD Works, and Why Gradient Accumulation Is Wastefulcited by 36
- 2024Does SGD really happen in tiny subspaces?cited by 35
- 2025Implicit Bias of Spectral Descent and Muon on Multiclass Separable Datacited by 33
- 2025Peri-LN: Revisiting Normalization Layer in the Transformer Architecturecited by 32
38 more
- 2025Isotropic Curvature Model for Understanding Deep Learning Optimization: Is Gradient Orthogonalization Optimal?cited by 30
- 2025COSMOS: A Hybrid Adaptive Optimizer for Memory-Efficient Training of LLMscited by 28
- 2026Preconditioning Benefits of Spectral Orthogonalization in Muoncited by 28
- 2025The Sharpness Disparity Principle in Transformers for Accelerating Language Model Pre-Trainingcited by 27
- 2025The emergence of sparse attention: impact of data distribution and benefits of repetitioncited by 25
- 2024Adam with model exponential moving average is effective for nonconvex optimizationcited by 22
- 2024AdaGrad under Anisotropic Smoothnesscited by 22
- 2024Adam Exploits ℓ_∞-geometry of Loss Landscape via Coordinate-wise Adaptivitycited by 20
- 2024SWAN: SGD with Normalization and Whitening Enables Stateless LLM Trainingcited by 20
- 2024Encryption-Friendly LLM Architecturecited by 15
- 2025Sculpting Subspaces: Constrained Full Fine-Tuning in LLMs for Continual Learningcited by 15
- 2025FedAdamW: A Communication-Efficient Optimizer with Convergence and Generalization Guarantees for Federated Large Modelscited by 15
- 2024AdaFisher: Adaptive Second Order Optimization via Fisher Informationcited by 14
- 2025Is your batch size the problem? Revisiting the Adam-SGD gap in language modelingcited by 14
- 2024MoFO: Momentum-Filtered Optimizer for Mitigating Forgetting in LLM Fine-Tuningcited by 13
- 2025Towards Quantifying the Hessian Structure of Neural Networkscited by 13
- 2025Unveiling the Basin-Like Loss Landscape in Large Language Modelscited by 13
- 2025The Rich and the Simple: On the Implicit Bias of Adam and SGDcited by 12
- 2024Addax: Utilizing Zeroth-Order Gradients to Improve Memory Efficiency and Performance of SGD for Fine-Tuning Language Modelscited by 11
- 2024Convergence Rate Analysis of LIONcited by 11
- 2026RMNP: Row-Momentum Normalized Preconditioning for Scalable Matrix-Based Optimizationcited by 11
- 2024Understanding Adam Requires Better Rotation Dependent Assumptionscited by 10
- 2024What Does It Mean to Be a Transformer? Insights from a Theoretical Hessian Analysiscited by 9
- 2025Understanding Overadaptation in Supervised Fine-Tuning: The Role of Ensemble Methodscited by 9
- 2026Learning Rate Matters: Vanilla LoRA May Suffice for LLM Fine-tuningcited by 9
- 2025PiKE: Adaptive Data Mixing for Large-Scale Multi-Task Learning Under Low Gradient Conflictscited by 8
- 2026Accelerating LLM Pre-Training through Flat-Direction Dynamics Enhancementcited by 8
- 2024HyperINF: Unleashing the HyperPower of the Schulz's Method for Data Influence Estimationcited by 7
- 2025On Provable Benefits of Muon in Federated Learningcited by 7
- 2024No More Adam: Learning Rate Scaling at Initialization is All You Needcited by 6
- 2025Mechanistic Insights into Grokking from the Embedding Layercited by 6
- 2025GradPower: Powering Gradients for Faster Language Model Pre-Trainingcited by 6
- 2026Do We Need Adam? Surprisingly Strong and Sparse Reinforcement Learning with SGD in LLMscited by 6
- 2026A Defense of the Quadratic Modelcited by 6
- 2024Exact Risk Curves of signSGD in High-Dimensions: Quantifying Preconditioning and Noise-Compression Effectscited by 5
- 2025On the Origin of Algorithmic Progress in AIcited by 5
- 2026On Surprising Effectiveness of Masking Updates in Adaptive Optimizerscited by 5
- 2026MUON+: Towards More Effective Muon via One Additional Normalization Step for LLM Pre-trainingcited by 5
50 most cited of 123 All 123 (JSON)
- 2026Learning Rate Transfer for Hybrid Transformer-SSM Architectures1 Oct 2026
- 2026How Does Local Landscape Geometry Evolve in Language Model Pre-Training?30 Sep 2026
- 2026Physical Muon: Orthogonalization as an Equilibrium Computation29 Sep 2026
- 2026Scalable Kronecker-Fisher Approximation: Efficient Hessian Analysis for Billion-Parameter Language Models Compression2 Sep 2026
- 2026Curvature-Conditioned Multiscale Momentum with Sphere Constraints for LLM Pretraining28 Aug 2026
- 2026Spectral Allocation: Why Muon Outperforms Adam, and How to Improve Muon26 Aug 2026
- 2026Blockwise Stabilized Adaptive Cubic Regularization with Subsolvers via Recurrence22 Aug 2026
- 2026Measuring Structured Predictability in Neural Training Dynamics: A Cross-Regime Study16 Aug 2026
- 2026MALT: Lightweight Curvature-Aware Muon via Diagonal Preconditioning5 Aug 2026
- 2026Muon Meets Mamba: Spectral Optimization for State Space Models4 Aug 2026
- 2026Distribution-Specific Curvature Control with Finite-Sample Guarantees for Open-Weight Safety24 Jul 2026
- 2026A Defense of the Quadratic Model23 Jul 2026
38 more
- 2026Muse: Representation Geometry of Muon Beyond Normalized Momentum16 Jul 2026
- 2026FedACT: Federated Adaptive Coordinate Trust Modulation for Robust Transformer Training under Data Heterogeneity4 Jul 2026
- 2026Staleness-Learning Rate Scaling Laws for Asynchronous RLHF1 Jul 2026
- 2026Schattor: Schatten-family methods for deep learning optimization14 Jun 2026
- 2026Beyond a Single Explanation of the Adam--SGD Gap12 Jun 2026
- 2026Muon Learns More Robust and Transferable Features than Adam8 Jun 2026
- 2026Why Muon Outperforms Adam: A Curvature Perspective3 Jun 2026
- 2026MAdam: Metric-Aware Multi-Objective Adam2 Jun 2026
- 2026Outer-Momentum Restarting in High-Dimensional Two-Phase Optimization27 May 2026
- 2026One LR Doesn't Fit All: Heavy-Tail Guided Layerwise Learning Rates for LLMs21 May 2026
- 2026AMO: Operator-level Adaptive Muon Orthogonalization18 May 2026
- 2026Revisiting the Adam-SGD Gap in LLM Pre-Training: The Role of Large Effective Learning Rates18 May 2026
- 2026Multi-Headed Transformer Architectures as Time-dependent Wasserstein Gradient Flows15 May 2026
- 2026PowerStep: Memory-Efficient Adaptive Optimization via ℓp-Norm Steepest Descent11 May 2026
- 2026Optimizer-Model Consistency: Full Finetuning with the Same Optimizer as Pretraining Forgets Less7 May 2026
- 2026Revealing Modular Gradient Noise Imbalance in LLMs: Calibrating Adam via Signal-to-Noise Ratio7 May 2026
- 2026Adapt or Forget: Provable Tradeoffs Between Adam and SGD in Nonstationary Optimization5 May 2026
- 2026On Adaptivity in Zeroth-Order Optimization5 May 2026
- 2026Nora: Normalized Orthogonal Row Alignment for Scalable Matrix Optimizer5 May 2026
- 2026Personalized Federated Learning for Gradient Alignment4 May 2026
- 2026AdaMeZO: Adam-style Zeroth-Order Optimizer for LLM Fine-tuning Without Maintaining the Moments1 May 2026
- 2026Generalization at the Edge of Stability21 Apr 2026
- 2026AdaCubic: An Adaptive Cubic Regularization Optimizer for Deep Learning10 Apr 2026
- 2026Efficient Unlearning through Maximizing Relearning Convergence Delay10 Apr 2026
- 2026Nexus: Same Pretraining Loss, Better Downstream Generalization via Common Minima10 Apr 2026
- 2026Optimal Projection-Free Adaptive SGD for Matrix Optimization2 Apr 2026
- 2026RMNP: Row-Momentum Normalized Preconditioning for Scalable Matrix-Based Optimization20 Mar 2026
- 2026Towards Understanding Adam Convergence on Highly Degenerate Polynomials10 Mar 2026
- 2026NerVE: Nonlinear Eigenspectrum Dynamics in LLM Feed-Forward Networks6 Mar 2026
- 2026HomeAdam: Adam and AdamW Algorithms Sometimes Go Home to Obtain Better Provable Generalization3 Mar 2026
- 2026Same Error, Different Function: The Optimizer as an Implicit Prior in Financial Time Series3 Mar 2026
- 2026Accelerating LLM Pre-Training through Flat-Direction Dynamics Enhancement26 Feb 2026
- 2026MUON+: Towards More Effective Muon via One Additional Normalization Step for LLM Pre-training25 Feb 2026
- 2026DP-FedAdamW: An Efficient Optimizer for Differentially Private Federated Large Models23 Feb 2026
- 2026On Surprising Effectiveness of Masking Updates in Adaptive Optimizers17 Feb 2026
- 2026Do We Need Adam? Surprisingly Strong and Sparse Reinforcement Learning with SGD in LLMs7 Feb 2026
- 2026Towards Robust Scaling Laws for Optimizers7 Feb 2026
- 2026Convex Dominance in Deep Learning I: A Scaling Law of Loss and Learning Rate6 Feb 2026
50 newest of 123 All 123 (JSON)
- 2025HessFormer: Hessians at Foundation Scalecited by 4
- 2025HessFormer: Hessians at Foundation Scale16 May 2025
- 2024Adam-mini: Use Fewer Learning Rates To Gain Morecited by 134
- 2024Heavy-Tailed Class Imbalance and Why Adam Outperforms Gradient Descent on Language Modelscited by 78
- 2024Preserving Diversity in Supervised Fine-Tuning of Large Language Modelscited by 68
- 2025ASGO: Adaptive Structured Gradient Optimizationcited by 55
- 2024APOLLO: SGD-like Memory, AdamW-level Performancecited by 50
- 2024Deconstructing What Makes a Good Optimizer for Language Modelscited by 40
- 2025In Search of Adam's Secret Saucecited by 40
- 2025Muon Outperforms Adam in Tail-End Associative Memory Learningcited by 38
- 2025Small Batch Size Training for Language Models: When Vanilla SGD Works, and Why Gradient Accumulation Is Wastefulcited by 36
- 2024Does SGD really happen in tiny subspaces?cited by 35
- 2025Implicit Bias of Spectral Descent and Muon on Multiclass Separable Datacited by 33
- 2025Peri-LN: Revisiting Normalization Layer in the Transformer Architecturecited by 32
12 most cited of 119 All 119 (JSON)
- 2026Learning Rate Transfer for Hybrid Transformer-SSM Architectures1 Oct 2026
- 2026How Does Local Landscape Geometry Evolve in Language Model Pre-Training?30 Sep 2026
- 2026Physical Muon: Orthogonalization as an Equilibrium Computation29 Sep 2026
- 2026Scalable Kronecker-Fisher Approximation: Efficient Hessian Analysis for Billion-Parameter Language Models Compression2 Sep 2026
- 2026Curvature-Conditioned Multiscale Momentum with Sphere Constraints for LLM Pretraining28 Aug 2026
- 2026Spectral Allocation: Why Muon Outperforms Adam, and How to Improve Muon26 Aug 2026
- 2026Blockwise Stabilized Adaptive Cubic Regularization with Subsolvers via Recurrence22 Aug 2026
- 2026Measuring Structured Predictability in Neural Training Dynamics: A Cross-Regime Study16 Aug 2026
- 2026MALT: Lightweight Curvature-Aware Muon via Diagonal Preconditioning5 Aug 2026
- 2026Distribution-Specific Curvature Control with Finite-Sample Guarantees for Open-Weight Safety24 Jul 2026
- 2026A Defense of the Quadratic Model23 Jul 2026
- 2026Muse: Representation Geometry of Muon Beyond Normalized Momentum16 Jul 2026
12 newest of 119 All 119 (JSON)