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Jun 26, 2015 at 11:32 answer added Anupam Singh timeline score: 1
Jul 7, 2011 at 2:41 answer added Larry timeline score: 1
Jun 21, 2011 at 8:09 comment added Tom De Medts In addition to Andy Putnam's comment, you might want to have a look at the related question mathoverflow.net/questions/59884/… that I asked some time ago.
Jun 21, 2011 at 6:39 answer added mathphysicist timeline score: 2
Jun 21, 2011 at 5:47 comment added Andy Putman To give you an idea of how hard it is to do linear algebra over rings that aren't fields, let's forget symplectic/orthogonal groups for a second and consider $G_n = SL_n(\mathbb{Z}[t,t^{-1}])$. In an absolute tour de force, Suslin proved that $G_n$ is generated by elementary matrices for $n$ at least $3$ (and, in particular, is finitely generated). However, for $n=2$ it is not known whether or not $G_n$ is generated by elementary matrices or finitely generated, though a deep theorem of Krstic-McCool shows that it is not finitely presentable.
Jun 21, 2011 at 4:59 comment added Andy B Are these linear algebraic groups defined over Z? If so you can consider them as group schemes over any ring.
Jun 21, 2011 at 2:33 comment added Andy Putman Is there something specific you want to know? It is a rather big subject, and it is hard to say anything nontrivial about totally general rings...
Jun 21, 2011 at 2:07 history asked Larry CC BY-SA 3.0