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Results tagged with classifying-spaces
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user 63965
The classifying space BG of a group G classifies principal G-bundles, in that homotopy classes of maps [X, BG] are naturally identified with isomorphism classes of principal G-bundles P ⭢ X.
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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
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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