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arXiv · 1109.0233

Kurosh rank of intersections of subgroups of free products of orderable groups

Yago Antolín·Armando Martino·Inga Schwabrow
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Abstract

We prove that the reduced Kurosh rank of the intersection of two subgroups $H$ and $K$ of a free product of right-orderable groups is bounded above by the product of the reduced Kurosh ranks of $H$ and $K$. In particular, taking the fundamental group of a graph of groups with trivial vertex and edge groups, and its Bass-Serre tree, our Theorem becomes the desired inequality of the usual Strengthened Hanna Neumann conjecture for free groups.

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Yago Antolín, Armando Martino, Inga Schwabrow. 2011-09-01. Kurosh rank of intersections of subgroups of free products of orderable groups. https://arxiv.org/abs/1109.0233

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