Forester has defined spaces of simplicial tree actions for a finitely generated group, called deformation spaces. Culler and Vogtmann’s Outer space is an example of a deformation space. Using ideas from Skora’s proof of the contractibility of Outer space, we show that under some mild hypotheses deformation spaces are contractible.
Clay, Matt  1
@article{10_2140_agt_2005_5_1481,
author = {Clay, Matt},
title = {Contractibility of deformation spaces of {G-trees}},
journal = {Algebraic and Geometric Topology},
pages = {1481--1503},
year = {2005},
volume = {5},
number = {4},
doi = {10.2140/agt.2005.5.1481},
url = {http://geodesic.mathdoc.fr/articles/10.2140/agt.2005.5.1481/}
}
Clay, Matt. Contractibility of deformation spaces of G-trees. Algebraic and Geometric Topology, Tome 5 (2005) no. 4, pp. 1481-1503. doi: 10.2140/agt.2005.5.1481
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