Stable Rationality and Cyclicity

David J Saltman

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arXiv · 2409.07240

Stable Rationality and Cyclicity

David J Saltman

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Abstract

There are two outstanding questions about division algebras of prime degree $p$. The first is whether they are cyclic, or equivalently crossed products. The second is whether the center, $Z(F,p)$, of the generic division algebra $UD(F,p)$ is stably rational over $F$. When $F$ is characteristic 0 and contains a primitive $p$ root of one, we show that there is a connection between these two questions. Namely, we show that if $Z(F,p)$ is not stably rational then $UD(F,p)$ is not cyclic.

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David J Saltman. 2024-09-11. Stable Rationality and Cyclicity. https://arxiv.org/abs/2409.07240

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