Timeline for Does every automorphism of G come from an inner automorphism of S_G?
Current License: CC BY-SA 2.5
6 events
| when toggle format | what | by | license | comment | |
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| Jun 12, 2010 at 18:13 | comment | added | Pete L. Clark | This result reminds me of the Skolem-Noether theorem on automorphisms of simple subalgebras of central simple algebras, or at least the special case where the CSA is $M_n(K)$. Is there any connection here? | |
| Jun 12, 2010 at 15:16 | comment | added | Jack Schmidt | The normalizer you mention is called the holomorph. It is the semi-direct product of G and Aut(G) and is very often used as a containing group where automorphisms become group elements. I think you'll find this in most group theory texts, though the permutation description is clearest in Burnside. Remember an automorphism is just a permutation of the elements of a group. | |
| Jun 11, 2010 at 19:29 | comment | added | S. Carnahan♦ | Note that left and right Cayley embeddings may be different (although this doesn't affect the answer to your question). | |
| Jun 11, 2010 at 19:26 | vote | accept | James D. Taylor | ||
| Jun 11, 2010 at 19:24 | answer | added | Simon Thomas | timeline score: 16 | |
| Jun 11, 2010 at 19:14 | history | asked | James D. Taylor | CC BY-SA 2.5 |