Timeline for Is there a classification relating split extensions $G$ by $K$ and homomorphisms $G \to \mathrm{Aut}(K)$?
Current License: CC BY-SA 2.5
2 events
| when toggle format | what | by | license | comment | |
|---|---|---|---|---|---|
| May 4, 2010 at 17:41 | comment | added | Dan Ramras | For example, there are semi-direct products in which the action is non-trivial, and yet the group is isomorphic to a direct product. This happens if you let $H$ act on $G$ by inner automorphisms of $G$: if $H$ acts through a map $f:G \rightarrow H$, then the isomorphism $G \rtimes H \rightarrow G \times H$ sends $(g,h)$ to $(g f(h), h)$. | |
| May 4, 2010 at 17:24 | history | answered | Mariano Suárez-Álvarez | CC BY-SA 2.5 |