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arXiv · 2406.10609

Orthogonal involutions over fields with I^3=0

Karim Johannes Becher·Fatma Kader Bingöl
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Abstract

We provide upper bounds on the u-invariant for skew-hermitian forms over a quaternion algebra with its canonical involution in terms of the u-invariant of the base field F of characteristic different from 2 when I^3F = 0.

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Karim Johannes Becher, Fatma Kader Bingöl. 2024-06-15. Orthogonal involutions over fields with I^3=0. https://doi.org/10.1016/j.jpaa.2025.107979

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