# Forget BIT, It is All about TOKEN: Towards Semantic Information Theory for LLMs

arXiv: https://arxiv.org/abs/2511.01202 · HTML: https://mlsanity.com/paper/2511.01202/

## Key facts

- Cited by 3 papers in the map (data through 14 Oct 2026).
- Builds on 26 of its 102 references that are in the map.
- First posted on arXiv 3 Nov 2025.

## Builds on (most cited first, 26 of 26)

- [Attention Is All You Need](https://mlsanity.com/paper/1706.03762/) (2017)
- [Language Models are Few-Shot Learners](https://mlsanity.com/paper/2005.14165/) (2020)
- [Training language models to follow instructions with human feedback](https://mlsanity.com/paper/2203.02155/) (2022)
- [Direct Preference Optimization: Your Language Model is Secretly a Reward Model](https://mlsanity.com/paper/2305.18290/) (2023)
- [Representation Learning with Contrastive Predictive Coding](https://mlsanity.com/paper/1807.03748/) (2018)
- [DeepSeek-R1: Incentivizing Reasoning Capability in LLMs via Reinforcement Learning](https://mlsanity.com/paper/2501.12948/) (2025)
- [Mamba: Linear-Time Sequence Modeling with Selective State Spaces](https://mlsanity.com/paper/2312.00752/) (2023)
- [Efficient Estimation of Word Representations in Vector Space](https://mlsanity.com/paper/1301.3781/) (2013)
- [Distributed Representations of Words and Phrases and their Compositionality](https://mlsanity.com/paper/1310.4546/) (2013)
- [Deep contextualized word representations](https://mlsanity.com/paper/1802.05365/) (2018)
- [Enriching Word Vectors with Subword Information](https://mlsanity.com/paper/1607.04606/) (2016)
- [Transformers are SSMs: Generalized Models and Efficient Algorithms Through Structured State Space Duality](https://mlsanity.com/paper/2405.21060/) (2024)
- [Large Language Diffusion Models](https://mlsanity.com/paper/2502.09992/) (2025)
- [Optimizing Neural Networks with Kronecker-factored Approximate Curvature](https://mlsanity.com/paper/1503.05671/) (2015)
- [On Variational Bounds of Mutual Information](https://mlsanity.com/paper/1905.06922/) (2019)
- [Gated Delta Networks: Improving Mamba2 with Delta Rule](https://mlsanity.com/paper/2412.06464/) (2024)
- [Opening the Black Box of Deep Neural Networks via Information](https://mlsanity.com/paper/1703.00810/) (2017)
- [Hopfield Networks is All You Need](https://mlsanity.com/paper/2008.02217/) (2020)
- [Text and Code Embeddings by Contrastive Pre-Training](https://mlsanity.com/paper/2201.10005/) (2022)
- [A mathematical perspective on Transformers](https://mlsanity.com/paper/2312.10794/) (2023)
- [Gromov-Wasserstein Alignment of Word Embedding Spaces](https://mlsanity.com/paper/1809.00013/) (2018)
- [Structured Attention Networks](https://mlsanity.com/paper/1702.00887/) (2017)
- [From Tokens to Thoughts: How LLMs and Humans Trade Compression for Meaning](https://mlsanity.com/paper/2505.17117/) (2025)
- [Beyond Scaling Laws: Understanding Transformer Performance with Associative Memory](https://mlsanity.com/paper/2405.08707/) (2024)
- [TREET: TRansfer Entropy Estimation via Transformers](https://mlsanity.com/paper/2402.06919/) (2024)
- [A Constrained BA Algorithm for Rate-Distortion and Distortion-Rate Functions](https://mlsanity.com/paper/2305.02650/) (2023)

## Built on by (most cited first, 3 of 3)

- [A Categorical Analysis of Large Language Models and Why LLMs Circumvent the Symbol Grounding Problem](https://mlsanity.com/paper/2512.09117/) (2025)
- [TONIC: Token-Centric Semantic Communication for Task-Oriented Wireless Systems](https://mlsanity.com/paper/2605.21553/) (2026)
- [TWIST: Closed-Loop token Synchronization for Application-Aware Wireless Digital Twins](https://mlsanity.com/paper/2605.27205/) (2026)

## Abstract (arXiv)

Despite the empirical successes of Large Language Models (LLMs), the prevailing paradigm is heuristic and experiment-driven, tethered to massive compute and data, while a first-principles theory remains absent. This treatise develops a Semantic Information Theory at the confluence of statistical physics, signal processing, and classical information theory, organized around a single paradigm shift: replacing the classical BIT - a microscopic substrate devoid of semantic content - with the macroscopic TOKEN as the atomic carrier of meaning and reasoning. Within this framework we recast attention and the Transformer as energy-based models, and interpret semantic embedding as vectorization on the semantic manifold. Modeling the LLM as a stateful channel with feedback, we adopt Massey's directed information as the native causal measure of autoregressive generation, from which we derive a *directed rate-distortion function for pre-training, a directed rate-reward function for RL-based post-training, and a sub-martingale account of inference-time semantic information flow. This machinery makes precise the identification of next-token prediction with Granger causal inference, and sharpens the limits of LLM reasoning against Pearl's Ladder of Causation - affirming that *whereas the BIT defined the Information Epoch, the TOKEN will define the AI Epoch.
