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arXiv · 2206.05987

Isotropy of quadratic forms over function fields in characteristic 2

Kristýna Zemková
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Abstract

We extend to characteristic two recent results about isotropy of quadratic forms over function fields. In particular, we provide a characterization of function fields not only of quadratic forms but also more generally of polynomials in several variables, over which a quadratic form becomes isotropic. As an application of these results, we obtain criteria for stable birational equivalence of quadratic forms.

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Kristýna Zemková. 2022-06-13. Isotropy of quadratic forms over function fields in characteristic 2. https://doi.org/10.1080/00927872.2024.2346638

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