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Tameness and geodesic cores of subgroups

Published online by Cambridge University Press:  09 April 2009

Rita Gitik
Affiliation:
A & H Consultants Ann Arbor, MI 48104 USA e-mail: ritagtk@math.lsa.umich.edu
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Abstract

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Let N be a finitely generated normal subgroup of a finitely generated group G. We show that if the trivial subgroup is tame in the factor group G/N, then N is that in G. We also give a short new proof of the fact that quasiconvex subgroups of negatively curved groups are tame. The proof utilizes the concept of the geodesic core of the subgroup and is related to the Dehn algorithm.

Type
Research Article
Copyright
Copyright © Australian Mathematical Society 2000

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