Lower central subgroups of a free group and its subgroup

Minkyoung Song

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arXiv · 1807.04002

Lower central subgroups of a free group and its subgroup

Minkyoung Song

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Abstract

For a given free group $F$ of arbitrary rank (possibly infinite), and its subgroup $G$, we address the question whether a lower central subgroup of $G$ can contain a lower central subgroup of $F$. We show that the answer is no if $G$ does not normally generate $F$. The question comes from a study of Hirzebruch-type invariants from iterated $p$-covers for 3-dimensional homology cylinders.

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Minkyoung Song. 2018-07-11. Lower central subgroups of a free group and its subgroup. https://arxiv.org/abs/1807.04002

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