Timeline for Are there arbitrarily sparse "lattices" in negatively curved symmetric spaces?
Current License: CC BY-SA 2.5
7 events
| when toggle format | what | by | license | comment | |
|---|---|---|---|---|---|
| May 30, 2010 at 8:31 | vote | accept | Sergei Ivanov | ||
| May 30, 2010 at 0:55 | comment | added | Victor Protsak | Sergei: The fact that cocompact lattices exist doesn't just follow from abstract nonsense type arguments, in fact, Margulis showed that they don't exist for some homogeneous spaces $G/H$ with semisimple $G$ and non-compact $H.$ So some version of Borel and Harish-Chandra is necessary (if I'm not mistaken, the mere existence part is due to Borel alone). | |
| May 29, 2010 at 23:55 | answer | added | Ian Agol | timeline score: 11 | |
| May 29, 2010 at 23:08 | comment | added | Sergei Ivanov | Thanks! One stupid little thing remains: why do co-compact subgroups exist? | |
| May 29, 2010 at 22:44 | answer | added | coudy | timeline score: 3 | |
| May 29, 2010 at 22:23 | comment | added | Greg Kuperberg | Malcev's theorem: Every finitely generated group of matrices is residually finite. | |
| May 29, 2010 at 22:20 | history | asked | Sergei Ivanov | CC BY-SA 2.5 |