GeoLAN: Geometric Learning of Latent Explanatory Directions in Large Language Models
Paper · 2026 · Tianyu Pan and Damon L. Woodard
Summary
Large language models are hard to inspect. Post hoc tools such as saliency maps or sparse autoencoders run into superposition, and hidden states tend to be anisotropic, crowding into a few dominant directions. GeoLAN addresses this during training rather than after it. The authors treat each token's layer-by-layer hidden states as a path, or "tube", through representation space. They borrow the idea of stickiness from the recent proof of the Kakeya conjecture in three dimensions and state two Wolff-style axioms. One limits how many token tubes can pack into a narrow region. The other limits attention heads from collapsing onto the same subspace. A theorem shows that K-sticky models split into nearly orthogonal "grains" with bounded output sensitivity. Two differentiable penalties, KT-CW and KT-Attn, enforce the axioms in practice. On Gemma-3 (1B, 4B, 12B) and Llama-3-8B, GeoLAN frequently keeps task performance intact, yields better geometric measurements, and lessens certain biases. The gains are clearest in mid-sized models. The work points toward interpretability that is built into training rather than reconstructed afterward.
Key points
- The framework has two regularizers. Katz-Tao Convex Wolff (KT-CW) pushes toward isotropy by using random projections to match projection variance to 1/d. Katz-Tao Attention (KT-Attn) discourages low-rank, collapsed attention routing.
- The theory is inspired by sticky Kakeya sets (Wang and Zahl, 2025). The Semantic Stickiness Theorem claims a grain decomposition, near-orthogonality bounded by O(K⁻¹), and a Lipschitz robustness bound.
- The models tested are Gemma-3 1B, 4B and 12B, plus Llama-3-8B. Llama-3-8B and other mid-sized models benefit most. The 1B model can be harmed, and Gemma-3-12B shows an accuracy drop.
- On CrowS-Pairs, Gemma-3-12B shows a small but statistically significant reduction in stereotype rate, together with a modest decline in clean accuracy.
- Computing the KT-CW loss slows training throughput by about 15–20%. Code is released on GitHub (GeoLAN_ACL26).
Institutions
Fields, topics and concepts
📚 Shelves 4The field of science this work belongs to (OpenAlex fields).Computer Science · 18,614 worksArtificial Intelligence · 17,965 worksArts and Humanities · 17,450 worksLanguage and Linguistics · 17,296 works
🧭 Topics 1Research subjects and languages the work is about.Language models & pretraining · 3,894 works
Cite
Cite as Tianyu Pan and Damon L. Woodard. 2026. GeoLAN: Geometric Learning of Latent Explanatory Directions in Large Language Models. Findings of the Association for Computational Linguistics: ACL 2026.
@inproceedings{pan2026geolan,
title = {{GeoLAN: Geometric Learning of Latent Explanatory Directions in Large Language Models}},
author = {Tianyu Pan and Damon L. Woodard},
booktitle = {Findings of the Association for Computational Linguistics: ACL 2026},
year = {2026},
doi = {10.18653/v1/2026.findings-acl.271},
url = {https://doi.org/10.18653/v1/2026.findings-acl.271}
}References
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