Timeline for Irreducible reps and characters of $G \rtimes A$
Current License: CC BY-SA 3.0
7 events
| when toggle format | what | by | license | comment | |
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| Jan 21, 2016 at 16:41 | vote | accept | CommunityBot | ||
| Jan 13, 2016 at 4:31 | history | edited | user35360 | CC BY-SA 3.0 |
added 2 characters in body
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| Jan 12, 2016 at 17:04 | answer | added | Qiaochu Yuan | timeline score: 7 | |
| Jan 12, 2016 at 11:49 | answer | added | Geoff Robinson | timeline score: 9 | |
| Jan 12, 2016 at 11:43 | comment | added | Derek Holt | Examples like the one you mention (cyclic extensions of simple groups) are in the ATLAS, and you can see easily which characters of $M_{12}$ are stabilized by the automorphism and extend to a character of the larger group, and which ones are not stabilized and give rise to an irreducible induced representation of $M_{12}.2$ of twice the degree. | |
| Jan 12, 2016 at 11:25 | comment | added | Geoff Robinson | In general, you need to understand Clifford's Theorem, and for each irreducible character $\chi$ of $G$, you need to know the stabilizer subgroup in $A$ of $\chi$. Even with this knowledge, it is in general not straightforward to compute the character table of $GA$, and I know of no single "recipe". | |
| Jan 12, 2016 at 11:00 | history | asked | user35360 | CC BY-SA 3.0 |