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arXiv · 1511.03370

Linkage of Quadratic Pfister Forms

Adam Chapman·Shira Gilat·Uzi Vishne
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Abstract

We study the necessary conditions for sets of quadratic $n$-fold Pfister forms to have a common $(n-1)$-fold Pfister factor. For any set $S$ of $n$-fold Pfister forms generating a subgroup of $I_q^n F/I_q^{n+1} F$ of order $2^s$ in which every element has an $n$-fold Pfister representative, we associate an invariant in $I_q^{n+1} F$ which lives inside $I_q^{n+s-1} F$ when the forms in $S$ have a common $(n-1)$-fold Pfister factor. We study the properties of this invariant and compute it explicitly in a few interesting cases.

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Adam Chapman, Shira Gilat, Uzi Vishne. 2015-11-11. Linkage of Quadratic Pfister Forms. https://arxiv.org/abs/1511.03370

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