Timeline for About non-abelian finite simple groups
Current License: CC BY-SA 4.0
8 events
| when toggle format | what | by | license | comment | |
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| Jan 24, 2021 at 7:20 | comment | added | ebrahimi | Thanks for your comments. I am working on almost simple groups and so need to answer this question. | |
| Jan 23, 2021 at 17:54 | comment | added | Richard Lyons | @GeoffRobinson: There are no exceptions. Outer diagonal automorphisms are matched by the center of the universal version, so can't be coprime. | |
| Jan 23, 2021 at 14:45 | comment | added | Geoff Robinson | You can discount sporadic simple groups, which always have outer automorphism groups of order at most $2$, and always have even order. You can also discount alternating groups ( $A_{6}$ needs a little extra care. So the answer is determined by simple groups of Lie type. The outer automorphisms of such a group are products of graph, diagonal, and field automorphisms. There may be some small exceptions, but it is usually the field automorphisms which have order coprime to the order of the simple group (if any at all do). | |
| Jan 23, 2021 at 13:26 | history | edited | YCor | CC BY-SA 4.0 |
formatting, changed tags
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| Jan 23, 2021 at 4:47 | comment | added | markvs | $Out(S)$ is usually very small. Can you use that? See mathoverflow.net/questions/20831/… and answers there. | |
| Jan 23, 2021 at 4:33 | comment | added | Yemon Choi | Could you say a bit more about the motivation for this question? That is, are there some theoretical reasons for hoping it is true, or some numerical evidence? | |
| Jan 23, 2021 at 4:30 | review | First posts | |||
| Jan 23, 2021 at 7:49 | |||||
| Jan 23, 2021 at 4:26 | history | asked | ebrahimi | CC BY-SA 4.0 |