# Quantifying Concentration Phenomena of Mean-Field Transformers in the Low-Temperature Regime

arXiv: https://arxiv.org/abs/2605.10931 · HTML: https://mlsanity.com/paper/2605.10931/

## Key facts

- Cited by 5 papers in the map (data through 14 Oct 2026).
- Builds on 39 of its 47 references that are in the map.
- First posted on arXiv 11 May 2026.

## Builds on (most cited first, 30 of 39)

- [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)
- [Language Models are Few-Shot Learners](https://mlsanity.com/paper/2005.14165/) (2020)
- [The Llama 3 Herd of Models](https://mlsanity.com/paper/2407.21783/) (2024)
- [LLaMA: Open and Efficient Foundation Language Models](https://mlsanity.com/paper/2302.13971/) (2023)
- [Neural Machine Translation by Jointly Learning to Align and Translate](https://mlsanity.com/paper/1409.0473/) (2014)
- [On the Opportunities and Risks of Foundation Models](https://mlsanity.com/paper/2108.07258/) (2021)
- [ALBERT: A Lite BERT for Self-supervised Learning of Language Representations](https://mlsanity.com/paper/1909.11942/) (2019)
- [Root Mean Square Layer Normalization](https://mlsanity.com/paper/1910.07467/) (2019)
- [Transformers learn in-context by gradient descent](https://mlsanity.com/paper/2212.07677/) (2022)
- [Universal Transformers](https://mlsanity.com/paper/1807.03819/) (2018)
- [A mathematical perspective on Transformers](https://mlsanity.com/paper/2312.10794/) (2023)
- [The emergence of clusters in self-attention dynamics](https://mlsanity.com/paper/2305.05465/) (2023)
- [Sinkformers: Transformers with Doubly Stochastic Attention](https://mlsanity.com/paper/2110.11773/) (2021)
- [Dynamic metastability in the self-attention model](https://mlsanity.com/paper/2410.06833/) (2024)
- [Emergence of meta-stable clustering in mean-field transformer models](https://mlsanity.com/paper/2410.23228/) (2024)
- [Clustering in Causal Attention Masking](https://mlsanity.com/paper/2411.04990/) (2024)
- [A Unified Perspective on the Dynamics of Deep Transformers](https://mlsanity.com/paper/2501.18322/) (2025)
- [The Mean-Field Dynamics of Transformers](https://mlsanity.com/paper/2512.01868/) (2025)
- [Quantitative Clustering in Mean-Field Transformer Models](https://mlsanity.com/paper/2504.14697/) (2025)
- [A multiscale analysis of mean-field transformers in the moderate interaction regime](https://mlsanity.com/paper/2509.25040/) (2025)
- [Geometric Dynamics of Signal Propagation Predict Trainability of Transformers](https://mlsanity.com/paper/2403.02579/) (2024)
- [A consensus-based model for global optimization and its mean-field limit](https://mlsanity.com/paper/1604.05648/) (2016)
- [Critical attention scaling in long-context transformers](https://mlsanity.com/paper/2510.05554/) (2025)
- [Consensus-Based Optimization Methods Converge Globally](https://mlsanity.com/paper/2103.15130/) (2021)
- [The Asymptotic Behavior of Attention in Transformers](https://mlsanity.com/paper/2412.02682/) (2024)
- [Synchronization of mean-field models on the circle](https://mlsanity.com/paper/2507.22857/) (2025)
- [On the Structure of Stationary Solutions to McKean-Vlasov Equations with Applications to Noisy Transformers](https://mlsanity.com/paper/2510.20094/) (2025)
- [Normalization in Attention Dynamics](https://mlsanity.com/paper/2510.22026/) (2025)
- [Multistability of Self-Attention Dynamics in Transformers](https://mlsanity.com/paper/2511.11553/) (2025)

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

- [On the Diverse Dynamical Behaviors Arising in Deep Linear Transformers](https://mlsanity.com/paper/2607.18584/) (2026)
- [Multi-Headed Transformer Architectures as Time-dependent Wasserstein Gradient Flows](https://mlsanity.com/paper/2605.18870/) (2026)
- [Reachability and asymptotics of Gaussian Transformer dynamics](https://mlsanity.com/paper/2606.07600/) (2026)
- [Random Quadratic Form with random forcing: Metastable synchronization by noise](https://mlsanity.com/paper/2608.16664/) (2026)
- [The Role of Feed-Forward Layers in Transformer Dynamics](https://mlsanity.com/paper/2609.36230/) (2026)

## Abstract (arXiv)

Transformers with self-attention modules as their core components have become an integral architecture in modern large language and foundation models. In this paper, we study the evolution of tokens in deep encoder-only transformers at inference time which is described in the large-token limit by a mean-field continuity equation. Leveraging ideas from the convergence analysis of interacting multi-particle systems, with particles corresponding to tokens, we prove that the token distribution rapidly concentrates onto the push-forward of the initial distribution under a projection map induced by the key, query, and value matrices, and remains metastable for moderate times. Specifically, we show that the Wasserstein distance of the two distributions scales like √log(β+1)/βexp(Ct)+exp(-ct) in terms of the temperature parameter β-1→ 0 and inference time t≥ 0. For the proof, we establish Lyapunov-type estimates for the zero-temperature equation, identify its limit as t→∞, and employ a stability estimate in Wasserstein space together with a quantitative Laplace principle to couple the two equations. Our result implies that for time scales of order logβ the token distribution concentrates at the identified limiting distribution. Numerical experiments confirm this and, beyond that, complement our theory by showing that for finite β and large t the dynamics enter a different terminal phase, dominated by the spectrum of the value matrix.
