Covering theory for complexes of groups

Seonhee Lim; Anne Thomas

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Covering theory for complexes of groups

Seonhee Lim·Anne Thomas

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Abstract

We develop an explicit covering theory for complexes of groups, parallel to that developed for graphs of groups by Bass. Given a covering of developable complexes of groups, we construct the induced monomorphism of fundamental groups and isometry of universal covers. We characterize faithful complexes of groups and prove a conjugacy theorem for groups acting freely on polyhedral complexes. We also define an equivalence relation on coverings of complexes of groups, which allows us to construct a bijection between such equivalence classes, and subgroups or overgroups of a fixed lattice $Γ$ in the automorphism group of a locally finite polyhedral complex $X$.

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BibTeX RIS

Seonhee Lim, Anne Thomas. 2007-10-04. Covering theory for complexes of groups. https://arxiv.org/abs/math/0605303

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