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arXiv · 1901.00358

Linkage of Symbol $p$-Algebras of Degree 3

Adam Chapman
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Abstract

Given a field $F$ of characteristic $3$ and division symbol $p$-algebras $[\alpha,\beta)_{3,F}$ and $[\alpha,\gamma)_{3,F}$ of degree $3$ over $F$, we prove that if $\alpha \text{dlog}(\beta)\wedge \text{dlog}(\gamma)$ is trivial in the Kato-Milne cohomology group $H_3^3(F)$ then the algebras share a common splitting field which is an inseparable degree 3 extension of either $F$ or a quadratic extension of $F$. In the special case of quadratically closed fields, if $\alpha \text{dlog}(\beta)\wedge \text{dlog}(\gamma)=0$, then they share an inseparable degree 3 extension of $F$.

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Adam Chapman. 2019-01-02. Linkage of Symbol $p$-Algebras of Degree 3. https://arxiv.org/abs/1901.00358

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