Talk:Group ring
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Some of the edits I just made were based on memory and could thus be slightly wrong. In particular, I'm not sure about the norm used to define the non-reduced C* algebra. Prumpf 00:48, 10 Sep 2004 (UTC)
- It looks right to me. Also various relations between representations weakly contained in the left regular rep and the reduced C*-algebra should be put in at some point. I also think the name group algebra is preferable to group ring.CSTAR 01:02, 10 Sep 2004 (UTC)
There used to be separate group ring and group algebra articles; then they were merged. We need group rings such as Z[G] for abstract algebra. So, I think we should probably go back, now, to separate pages. Charles Matthews 07:47, 10 Sep 2004 (UTC)
- My proposal was moving this page to group algebra and keeping only that one article as long as it doesn't get too long. I guess we could turn it into a disambiguation page as well, but I think I'd prefer some common text. For example, all group algebras are commutative if G is abelian (with the converse being true in the non-pathological cases), and for finite groups, all group algebras coincide (if considered over the complex numbers).
- Maybe you want to fix the group ring section? Some previous author seems to have focussed on group rings over a field, but in my experience, the most common case is ZG, so maybe at least that case should be explained in a bit more detail. Prumpf 11:14, 10 Sep 2004 (UTC)
- A very common case is CG, since this is the fundamental object of study in complex group representations. This probably explains the bias. Ben 11:26, 11 August 2006 (UTC)
Group ring definition does not imply usually that the ring is commutative. Jean-Louis Margot 12:12, 30 Sep 2005 (UTC)
This could use a clean up - at the moment it's a bit of a hodge podge of facts and statements. Leland McInnes 21:16, 28 January 2006 (UTC)
