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arXiv · 1811.02145

Rationality problem for norm one tori in small dimensions

Sumito Hasegawa·Akinari Hoshi·Aiichi Yamasaki
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Abstract

We classify stably/retract rational norm one tori in dimension $n-1$ for $n=2^e$ $(e\geq 1)$ is a power of $2$ and $n=12, 14, 15$. Retract non-rationality of norm one tori for primitive $G\leq S_{2p}$ where $p$ is a prime number and for the five Mathieu groups $M_n\leq S_n$ $(n=11,12,22,23,24)$ is also given.

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Sumito Hasegawa, Akinari Hoshi, Aiichi Yamasaki. 2018-11-06. Rationality problem for norm one tori in small dimensions. https://arxiv.org/abs/1811.02145

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