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arXiv · 1312.1064

Scale-multiplicative semigroups and geometry: automorphism groups of trees

Udo Baumgartner·Jacqui Ramagge·George A. Willis
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Abstract

A scale-multiplicative semigroup in a totally disconnected, locally compact group $G$ is one for which the restriction of the scale function on $G$ is multiplicative. The maximal scale-multiplicative semigroups in groups acting 2-transitively on the set of ends of trees without leaves are determined in this paper and shown to correspond to geometric features of the tree.

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Udo Baumgartner, Jacqui Ramagge, George A. Willis. 2013-12-04. Scale-multiplicative semigroups and geometry: automorphism groups of trees. https://arxiv.org/abs/1312.1064

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