Every orientable 3-manifold is a B\Gamma
摘要
We show that every orientable 3-manifold is a classifying space B\Gamma where \Gamma is a groupoid of germs of homeomorphisms of R. This follows by showing that every orientable 3-manifold M admits a codimension one foliation F such that the holonomy cover of every leaf is contractible. The F we construct can be taken to be C^1 but not C^2. The existence of such an F answers positively a question posed by Tsuboi [Classifying spaces for groupoid structures, notes from minicourse at PUC, Rio de Janeiro (2001)], but leaves open the question of whether M = B\Gamma for some C^\infty groupoid \Gamma.
关键词
引用
@article{arxiv.math/0206066,
title = {Every orientable 3-manifold is a B\Gamma},
author = {Danny Calegari},
journal= {arXiv preprint arXiv:math/0206066},
year = {2014}
}
备注
Published by Algebraic and Geometric Topology at http://www.maths.warwick.ac.uk/agt/AGTVol2/agt-2-21.abs.html Version 2: Correction to the Example on page 436