Hasse norm principle for $M_{11}$ and $J_1$ extensions

Akinari Hoshi; Kazuki Kanai; Aiichi Yamasaki

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arXiv · 2210.09119

Hasse norm principle for $M_{11}$ and $J_1$ extensions

Akinari Hoshi·Kazuki Kanai·Aiichi Yamasaki

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Abstract

We give a necessary and sufficient condition for the Hasse norm principle for field extensions $K/k$ when the Galois groups ${\rm Gal}(L/k)$ of the Galois closure $L/k$ of $K/k$ are isomorphic to the Mathieu group $M_{11}$ of degree $11$ of order $7920$ or the Janko group $J_1$ of order $175560$ by determining $H^1(k,{\rm Pic}\, \overline{X})=0$ or $\mathbb{Z}/2\mathbb{Z}$ for norm one tori $T=R^{(1)}_{K/k}(\mathbb{G}_m)$ with a smooth $k$-compactification $X$ and $\overline{X}=X\times_k\overline{k}$. The result gives a first step towards understanding the all pictures of the Hasse norm principle for the $26$ sporadic simple groups.

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Akinari Hoshi, Kazuki Kanai, Aiichi Yamasaki. 2022-10-17. Hasse norm principle for $M_{11}$ and $J_1$ extensions. https://arxiv.org/abs/2210.09119

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