Abelian subgroups of pro-2 Galois groups

Efrat, Ido

doi:10.1090/S0002-9939-1995-1242081-X

Abelian subgroups of pro-$2$ Galois groups
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by Ido Efrat

Proc. Amer. Math. Soc. 123 (1995), 1031-1035

DOI: https://doi.org/10.1090/S0002-9939-1995-1242081-X

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Abstract:

Let $a(K)$ be the maximal cardinality $|I|$ such that $\mathbb {Z}_2^I$ is a closed subgroup of the maximal pro-2 Galois group of a field K. We prove estimates on $a(K)$ conjectured by Ware.

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