The $2$-adic Absolute Galois Group
Give a presentation for the absolute Galois group of the field of $2$-adic numbers as a profinite group.
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About the problem
Attempts by AI
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Mathematician survey
About the problem
The absolute Galois group of a field $K$ is the projective limit of all of the finite Galois groups $\operatorname{Gal}(E/K)$. It packages together the information about all finite extensions, and studying the Galois group of the rational field $\mathbb{Q}$ is a central problem in algebraic number theory. One method for approaching this group is to study the analogous Galois groups of p-adic fields $\mathbb{Q}_p$. In this case, there is an explicit presentation of $\operatorname{Gal}(\overline{\mathbb{Q}}_p/\mathbb{Q}_p)$ for $p>2$. For $p=2$, we have a description for the absolute Galois group of some extensions of $\mathbb{Q}_2$, but not for $\mathbb{Q}_2$ itself. Finding such a description would fill in a gap in our explicit understanding of Galois groups, and would have consequences in terms of counting p-adic fields with a given Galois group.
Warm-up: We ask for a presentation of the absolute Galois group of $\mathbb{Q}_3$, which is known.
Attempts by AI
We have evaluated the following models on this problem. “Warm-up” refers to an easier variant of the problem with a known solution.
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Mathematician survey
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