Covering groups of $M_{22}$ as regular Galois groups over $\mathbb{Q}$

Joachim König

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arXiv · 2012.11302

Covering groups of $M_{22}$ as regular Galois groups over $\mathbb{Q}$

Joachim König

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Abstract

We close a gap in the literature by showing that the full covering groups of the Mathieu group $M_{22}$ and of its automorphism group $Aut(M_{22})$ occur as the Galois group of $\mathbb{Q}$-regular Galois extensions of $\mathbb{Q}(t)$.

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Joachim König. 2020-12-21. Covering groups of $M_{22}$ as regular Galois groups over $\mathbb{Q}$. https://arxiv.org/abs/2012.11302

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