Timeline for Are there algorithms and/or criteria for determining if a group has a presentation with all commutator relators?
Current License: CC BY-SA 3.0
8 events
when toggle format | what | by | license | comment | |
---|---|---|---|---|---|
Sep 18, 2013 at 8:23 | comment | added | HJRW | Here's another necessary condition: if your group $G$ is not free, then $b_2(G)>0$. Stallings proved (Homology and central series of groups, J. Algebra) that, in a group with $H_2(G,\mathbb{Q})=0$, any linearly independent subset in $H_1$ generates a free subgroup. But the generating set in your presentation is linearly independent in $H_1$. | |
Sep 17, 2013 at 17:00 | history | edited | Nick Salter | CC BY-SA 3.0 |
added 47 characters in body
|
Sep 17, 2013 at 16:58 | comment | added | Nick Salter | Yes, I mean a product of commutators. I'll edit the language to make it more precise. | |
Sep 17, 2013 at 15:49 | comment | added | HJRW | To be clear, for you, a 'commutator relation' is a relation which is a product of commutators, right? | |
Sep 17, 2013 at 15:31 | comment | added | Nick Salter | Ah - that's a good point. I've edited my question. | |
Sep 17, 2013 at 15:30 | history | edited | Nick Salter | CC BY-SA 3.0 |
added 226 characters in body
|
Sep 17, 2013 at 15:23 | comment | added | Andy Putman | This is impossible. The trivial group is the only group with this property whose abelianization is trivial, so if you could solve this problem then you could decide whether a group presentation gave the trivial group. | |
Sep 17, 2013 at 15:18 | history | asked | Nick Salter | CC BY-SA 3.0 |