Search Results
| Search type | Search syntax |
|---|---|
| Tags | [tag] |
| Exact | "words here" |
| Author |
user:1234 user:me (yours) |
| Score |
score:3 (3+) score:0 (none) |
| Answers |
answers:3 (3+) answers:0 (none) isaccepted:yes hasaccepted:no inquestion:1234 |
| Views | views:250 |
| Code | code:"if (foo != bar)" |
| Sections |
title:apples body:"apples oranges" |
| URL | url:"*.example.com" |
| Saves | in:saves |
| Status |
closed:yes duplicate:no migrated:no wiki:no |
| Types |
is:question is:answer |
| Exclude |
-[tag] -apples |
| For more details on advanced search visit our help page | |
Results tagged with at.algebraic-topology
Search options not deleted
user 63965
Homotopy theory, homological algebra, algebraic treatments of manifolds.
6
votes
1
answer
194
views
A sufficient condition for $\pi_1(\operatorname B\Gamma) = 0$
I am currently reading Ghys and Sergiescu's paper Sur un groupe remarquable de difféomorphisms du cercle (French only I'm afraid), but part of their proof of Corollary 3.4 (page 20 of the pdf) is opaq …
- 171
1
vote
Accepted
A sufficient condition for $\pi_1(\operatorname B\Gamma) = 0$
Peter Greenberg's paper Pseudogroups from group actions held the key.
There is a weak equivalence between $\mathrm{B}\Gamma$ and $(\mathrm{B}K_0 \ast \mathrm{B}K_0) \vee (\mathrm{B}K/\mathrm{B}K_0)$, …
- 171