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arXiv · 2401.12515

Isotropy indices of Pfister multiples in characteristic two

Nico Lorenz·Kristýna Zemková
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Abstract

Let $F$ be a field of characteristic $2$, $\pi$ be an $n$-fold bilinear Pfister form over $F$ and $\varphi$ an arbitrary quadratic form over $F$. In this note, we investigate Witt index, defect, total isotropy index and higher isotropy indices of $\varphi$ and $\pi\otimes\varphi$ and prove relations among the indices of these two forms over certain field extensions.

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Nico Lorenz, Kristýna Zemková. 2024-01-23. Isotropy indices of Pfister multiples in characteristic two. https://doi.org/10.1016/j.jpaa.2024.107759

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