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Contractibility of deformation spaces of G-trees

Matt Clay
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Abstract

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.

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Matt Clay. 2005-11-24. Contractibility of deformation spaces of G-trees. https://doi.org/10.2140/agt.2005.5.1481

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