Abelian absolute Galois groups

Pub Date : 2024-02-02 DOI:10.1017/s0017089524000028
Moshe Jarden
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Abstract

Generalizing a result of Wulf-Dieter Geyer in his thesis, we prove that if $K$ is a finitely generated extension of transcendence degree $r$ of a global field and $A$ is a closed abelian subgroup of $\textrm{Gal}(K)$ , then ${\mathrm{rank}}(A)\le r+1$ . Moreover, if $\mathrm{char}(K)=0$ , then ${\hat{\mathbb{Z}}}^{r+1}$ is isomorphic to a closed subgroup of $\textrm{Gal}(K)$ .
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在推广沃尔夫-迪特尔-盖耶尔(Wulf-Dieter Geyer)论文中的一个结果的基础上,我们证明,如果 $K$ 是一个全域的超越度 $r$ 的有限生成扩展,并且 $A$ 是 $\textrm{Gal}(K)$ 的一个封闭无边子群,那么 ${mathrm{rank}}(A)\le r+1$ 。此外,如果 $\mathrm{char}(K)=0$ ,那么 ${hat\mathbb{Z}}^{r+1}$ 与 $textrm{Gal}(K)$ 的一个封闭子群同构。
本文章由计算机程序翻译,如有差异,请以英文原文为准。
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