arXiv Machine Learning By Andrew O'Desky

On attention heads and bilinear forms

Read the original on arXiv Machine Learning →

The paper investigates the symmetric and antisymmetric components of bilinear forms that arise in the attention heads of large language models. It introduces an orthogonally invariant profile map that projects real bilinear forms onto a three‑dimensional simplex, revealing that the profiles of trained bilinear forms tend to cluster near those of rank‑one bilinear forms. Additionally, the authors prove that for a Zariski‑dense subset of query‑key matrices, the symmetric part of a bilinear form in an attention head can be decomposed into a hyperbolic form plus a zero form.

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