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arXiv · 2607.27092

Sky sphere representation in language models

Aleksandr Berdnikov·Yevgeny Liokumovich
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Abstract

We analyze whether language models of size ~100B have a representation of the night sky map that is decodable from their residual stream. We find that most of the considered open-source models do have such a representation, and it often even surfaces to the top principal components on prompts that ask questions like ``what is close to this object in the night sky''. In all but one model this representation showed significant scores in LOO testing, containing up to 65-85% of variance ($R^2$-score) and having median angular error down to $12^\circ-21^\circ$. We verify that our representation is not a simple leak from a correlated flat representation. To our knowledge, this representation is the first example of a curved high-dimensional irreducible feature manifold. Codes used in the paper are published at https://github.com/l3erdnik/Decodable-sky

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Aleksandr Berdnikov, Yevgeny Liokumovich. 2026-07-29. Sky sphere representation in language models. https://arxiv.org/abs/2607.27092

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