# Infinite-Width Limit of a Single Attention Layer: Analysis via Tensor Programs

arXiv: https://arxiv.org/abs/2506.00846 · HTML: https://mlsanity.com/paper/2506.00846/

## Key facts

- Cited by 5 papers in the map (data through 14 Oct 2026).
- Builds on 31 of its 47 references that are in the map.
- First posted on arXiv 1 Jun 2025.

## Builds on (most cited first, 30 of 31)

- [Attention Is All You Need](https://mlsanity.com/paper/1706.03762/) (2017)
- [BERT: Pre-training of Deep Bidirectional Transformers for Language Understanding](https://mlsanity.com/paper/1810.04805/) (2018)
- [GPT-4 Technical Report](https://mlsanity.com/paper/2303.08774/) (2023)
- [Neural Tangent Kernel: Convergence and Generalization in Neural Networks](https://mlsanity.com/paper/1806.07572/) (2018)
- [A Survey of Large Language Models](https://mlsanity.com/paper/2303.18223/) (2023)
- [Deep Neural Networks as Gaussian Processes](https://mlsanity.com/paper/1711.00165/) (2017)
- [A Mean Field View of the Landscape of Two-Layers Neural Networks](https://mlsanity.com/paper/1804.06561/) (2018)
- [Gaussian Process Behaviour in Wide Deep Neural Networks](https://mlsanity.com/paper/1804.11271/) (2018)
- [Exponential expressivity in deep neural networks through transient chaos](https://mlsanity.com/paper/1606.05340/) (2016)
- [Deep Information Propagation](https://mlsanity.com/paper/1611.01232/) (2016)
- [Bayesian Deep Convolutional Networks with Many Channels are Gaussian Processes](https://mlsanity.com/paper/1810.05148/) (2018)
- [Tensor Programs I: Wide Feedforward or Recurrent Neural Networks of Any Architecture are Gaussian Processes](https://mlsanity.com/paper/1910.12478/) (2019)
- [Scaling Limits of Wide Neural Networks with Weight Sharing: Gaussian Process Behavior, Gradient Independence, and Neural Tangent Kernel Derivation](https://mlsanity.com/paper/1902.04760/) (2019)
- [Tensor Programs II: Neural Tangent Kernel for Any Architecture](https://mlsanity.com/paper/2006.14548/) (2020)
- [Toward Deeper Understanding of Neural Networks: The Power of Initialization and a Dual View on Expressivity](https://mlsanity.com/paper/1602.05897/) (2016)
- [Infinite attention: NNGP and NTK for deep attention networks](https://mlsanity.com/paper/2006.10540/) (2020)
- [Tensor Programs VI: Feature Learning in Infinite-Depth Neural Networks](https://mlsanity.com/paper/2310.02244/) (2023)
- [Mean Field Residual Networks: On the Edge of Chaos](https://mlsanity.com/paper/1712.08969/) (2017)
- [Scaling Exponents Across Parameterizations and Optimizers](https://mlsanity.com/paper/2407.05872/) (2024)
- [A Mean Field Theory of Batch Normalization](https://mlsanity.com/paper/1902.08129/) (2019)
- [Tensor Programs IIb: Architectural Universality of Neural Tangent Kernel Training Dynamics](https://mlsanity.com/paper/2105.03703/) (2021)
- [Tensor Programs III: Neural Matrix Laws](https://mlsanity.com/paper/2009.10685/) (2020)
- [The Shaped Transformer: Attention Models in the Infinite Depth-and-Width Limit](https://mlsanity.com/paper/2306.17759/) (2023)
- [Dynamical Isometry and a Mean Field Theory of RNNs: Gating Enables Signal Propagation in Recurrent Neural Networks](https://mlsanity.com/paper/1806.05394/) (2018)
- [Tensor Programs IVb: Adaptive Optimization in the Infinite-Width Limit](https://mlsanity.com/paper/2308.01814/) (2023)
- [Infinite Limits of Multi-head Transformer Dynamics](https://mlsanity.com/paper/2405.15712/) (2024)
- [Geometric Dynamics of Signal Propagation Predict Trainability of Transformers](https://mlsanity.com/paper/2403.02579/) (2024)
- [Effective Theory of Transformers at Initialization](https://mlsanity.com/paper/2304.02034/) (2023)
- [Wide Neural Networks with Bottlenecks are Deep Gaussian Processes](https://mlsanity.com/paper/2001.00921/) (2020)
- [Wide Neural Networks as Gaussian Processes: Lessons from Deep Equilibrium Models](https://mlsanity.com/paper/2310.10767/) (2023)

## Built on by (most cited first, 5 of 5)

- [Gaussian Equivalence for Self-Attention: Asymptotic Spectral Analysis of Attention Matrix](https://mlsanity.com/paper/2510.06685/) (2025)
- [A Unified Framework for Critical Scaling of Inverse Temperature in Self-Attention](https://mlsanity.com/paper/2605.12697/) (2026)
- [Quantitative Gaussian-Process limits of Tensor Programs](https://mlsanity.com/paper/2607.06290/) (2026)
- [Neural Network Quantum Field Theory from Transformer Architectures](https://mlsanity.com/paper/2602.10209/) (2026)
- [Linearized Attention Cannot Enter the Kernel Regime at Any Practical Width](https://mlsanity.com/paper/2603.13085/) (2026)

## Abstract (arXiv)

In modern theoretical analyses of neural networks, the infinite-width limit is often invoked to justify Gaussian approximations of neuron preactivations (e.g., via neural network Gaussian processes or Tensor Programs). However, these Gaussian-based asymptotic theories have so far been unable to capture the behavior of attention layers, except under special regimes such as infinitely many heads or tailored scaling schemes. In this paper, leveraging the Tensor Programs framework, we rigorously identify the infinite-width limit distribution of variables within a single attention layer under realistic architectural dimensionality and standard 1/√n-scaling with n dimensionality. We derive the exact form of this limit law without resorting to infinite-head approximations or tailored scalings, demonstrating that it departs fundamentally from Gaussianity. This limiting distribution exhibits non-Gaussianity from a hierarchical structure, being Gaussian conditional on the random similarity scores. Numerical experiments validate our theoretical predictions, confirming the effectiveness of our theory at finite width and accurate description of finite-head attentions. Beyond characterizing a standalone attention layer, our findings lay the groundwork for developing a unified theory of deep Transformer architectures in the infinite-width regime.
