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arXiv · 1009.4364

Subgroup Distortion in Wreath Products of Cyclic Groups

Tara Davis·Alexander Olshanskii
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Abstract

We study the effects of subgroup distortion in the wreath products A wr Z, where A is finitely generated abelian. We show that every finitely generated subgroup of A wr Z has distortion function equivalent to some polynomial. Moreover, for A infinite, and for any polynomial l^k, there is a 2-generated subgroup of A wr Z having distortion function equivalent to the given polynomial. Also a formula for the length of elements in arbitrary wreath product H wr G easily shows that the group Z_2 wr Z^2 has distorted subgroups, while the lamplighter group Z_2 wr Z has no distorted (finitely generated) subgroups.

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Tara Davis, Alexander Olshanskii. 2011-04-08. Subgroup Distortion in Wreath Products of Cyclic Groups. https://arxiv.org/abs/1009.4364

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