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arXiv · 1906.03730

Explicit methods for the Hasse norm principle and applications to $A_n$ and $S_n$ extensions

André Macedo·Rachel Newton
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Abstract

Let $K/k$ be an extension of number fields. We describe theoretical results and computational methods for calculating the obstruction to the Hasse norm principle for $K/k$ and the defect of weak approximation for the norm one torus $R^1_{K/k} \mathbb{G}_m$. We apply our techniques to give explicit and computable formulae for the obstruction to the Hasse norm principle and the defect of weak approximation when the normal closure of $K/k$ has symmetric or alternating Galois group.

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André Macedo, Rachel Newton. 2021-01-06. Explicit methods for the Hasse norm principle and applications to $A_n$ and $S_n$ extensions. https://arxiv.org/abs/1906.03730

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