Timeline for Elementary abelian 2-subgroups of $\mathrm{Aut}(\overline{\mathbb{Q}}/\mathbb{Q})$ (with and without choice)
Current License: CC BY-SA 4.0
5 events
| when toggle format | what | by | license | comment | |
|---|---|---|---|---|---|
| Jul 5, 2023 at 11:19 | comment | added | THC | @ArnoFehm: does Geyer use Choice to obtain that result ? | |
| Apr 20, 2023 at 13:45 | comment | added | THC | @ArnoFehm: so they are finite of size 2 ? | |
| Apr 20, 2023 at 13:38 | comment | added | Arno Fehm | Will Sawin answers the first question, and the structure of that subgroup is known (a result by Fried-Haran-Völklein). The abelian subgroups are also known, in particular every elementary 2-abelian subgroup is in fact cyclic (this I think is an older result by Geyer), see this answer: mathoverflow.net/a/352952/50351 | |
| Apr 20, 2023 at 12:58 | comment | added | Will Sawin | The subgroup generated by all involutions is the Galois group of $\overline{\mathbb Q}$ over the maximal totally real extension of $\mathbb Q$ as this is the fixed field of all the complex conjugations. | |
| Apr 20, 2023 at 10:49 | history | asked | THC | CC BY-SA 4.0 |