Timeline for Geometric model for classifying spaces of alternating groups
Current License: CC BY-SA 2.5
9 events
| when toggle format | what | by | license | comment | |
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| Jul 30, 2010 at 8:15 | comment | added | Dev Sinha | Natural is perhaps the wrong word (because of the connotations of functoriality). What I mean is more "found in nature." For example you wouldn't want to understand the classifying space of Z/p \times Z/p as some kind of "configurations with ordering up to equivalence" - one model found in nature is the product of Lens spaces. | |
| Jul 30, 2010 at 7:31 | comment | added | Victor Protsak | I don't understand the comment about "natural" models: the classifying space $BG$ is only defined up to homotopy and $BH=EG/H$ for $H<G$ is rather natural! | |
| Jul 1, 2010 at 8:58 | history | edited | Charles Matthews | CC BY-SA 2.5 |
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| Jul 1, 2010 at 5:13 | comment | added | Dev Sinha | Yes, but to get to more "natural" models requires at least a bit more than such a general construction (and presumably won't be possible for arbitrary subgroups). | |
| Jul 1, 2010 at 3:10 | comment | added | Bruce Westbury | For any subgroup $G\subset S_n$ you can proceed by: Take $E$ to be the universal cover of any classifying space of $S_n$. Then $E/G$ is a classifying space for $G$. This is implicit in the answers and in your examples. | |
| Jun 30, 2010 at 23:16 | vote | accept | Dev Sinha | ||
| Jun 30, 2010 at 23:10 | answer | added | Greg Kuperberg | timeline score: 12 | |
| Jun 30, 2010 at 23:00 | answer | added | Kevin Walker | timeline score: 22 | |
| Jun 30, 2010 at 22:27 | history | asked | Dev Sinha | CC BY-SA 2.5 |