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Jun 29, 2011 at 4:38 vote accept Lee
Jun 29, 2011 at 4:38 vote accept Lee
Jun 29, 2011 at 4:38
Jun 29, 2011 at 3:17 comment added S. Carnahan Your revised question amounts to studying maps of the form $\mathbb{F}_q[H] \to M_n(R)$, where $H$ is the Heisenberg group, and $R$ is your finite ring. This certainly makes sense, and Curtis and Reiner's book might be a decent reference.
Jun 29, 2011 at 1:08 history edited Lee
edited tags
Jun 29, 2011 at 1:01 history edited Lee CC BY-SA 3.0
made it more concretely
Jun 29, 2011 at 0:32 comment added Lee @Richard, David and Dan: I was meant to say maps from groups to matrices over a finite ring. I'll edit my question.
Jun 28, 2011 at 22:51 comment added Dan Ramras Representations of groups over finite fields (i.e. homomorphisms from a group to GL_n (F), where F is a finite field) is a big subject. David Benson has good books about it. But I'm still unclear on whether the OP was talking about maps from groups to matrices over a finite ring, or whether something else was intended.
Jun 28, 2011 at 20:59 comment added Johannes Hahn @David: That's not necessarily true. In modular representation theory $\mathcal{O}[G]$ (where $\mathcal{O}$ is a discrete valuation) and its modules are useful and important objects linking the representation theory over the quotient field (which is usually chosen to have characteristic 0) and the residue field (which is usually chosen to have positive characteristic) of $\mathcal{O}$.
Jun 28, 2011 at 19:33 answer added David White timeline score: 2
Jun 28, 2011 at 18:55 comment added David White I'm a bit confused by the pronouns. I think of representation theory of a group $G$ over $\mathbb{C}$ as the usually studied representation theory. Is the question whether we can replace $\mathbb{C}$ by a finite ring or whether we can replace $G$ by a finite ring? In the former case I think you gain nothing since your ring would need inverses to have a good theory and a finite division ring is a field. I'm searching now for a reference for the latter interpretation
Jun 28, 2011 at 16:54 comment added Richard Rast I believe Lee was wondering whether there was some good reason we shouldn't do representations over finite rings (there isn't), and if not, he would like a good reference to go read about them. I don't have one, but someone should post one.
Jun 28, 2011 at 14:07 comment added Theo Johnson-Freyd Dear Lee, There is, of course, much to be said about the representation theory of groups over finite rings. Indeed, there's much more than can be said in a MathOverflow post, and as such, your question is a bit more open-ended than would be best for this site. Please read mathoverflow.net/howtoask and consider revising this question to be more specific: what do you already know, and what in particular would you like to know?
Jun 28, 2011 at 13:42 history edited Lee CC BY-SA 3.0
added 28 characters in body
Jun 28, 2011 at 13:36 history asked Lee CC BY-SA 3.0