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arXiv · 0911.0134

Context-free pairs of groups. II - cuts, tree sets, and random walks

Wolfgang Woess
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Abstract

This is a continuation of the study, begun by Ceccherini-Silberstein and Woess, of context-free pairs of groups and the related context-free graphs in the sense of Muller and Schupp. Instead of the cones (connected components with respect to deletion of finite balls with respect to the graph metric), a more general approach to context-free graphs is proposed via tree sets consisting of cuts of the graph, and associated structure trees. The existence of tree sets with certain "good" properties is studied. With a tree set, a natural context-free grammar is associated. These investigations of the structure of context free pairs, resp. graphs are then applied to study random walk asymptotics via complex analysis.

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Wolfgang Woess. 2009-11-01. Context-free pairs of groups. II - cuts, tree sets, and random walks. https://arxiv.org/abs/0911.0134

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