Graph braid groups and right-angled Artin groups

Jee Hyoun Kim; Ki Hyoung Ko; Hyo Won Park

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arXiv · 0805.0082

Graph braid groups and right-angled Artin groups

Jee Hyoun Kim·Ki Hyoung Ko·Hyo Won Park

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Abstract

We give a necessary and sufficient condition for a graph to have a right-angled Artin group as its braid group for braid index $\ge 5$. In order to have the necessity part, graphs are organized into small classes so that one of homological or cohomological characteristics of right-angled Artin groups can be applied. Finally we show that a given graph is planar iff the first homology of its 2-braid group is torsion-free and leave the corresponding statement for $n$-braid groups as a conjecture along with few other conjectures about graphs whose braid groups of index $\le 4$ are right-angled Artin groups.

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Jee Hyoun Kim, Ki Hyoung Ko, Hyo Won Park. 2010-06-13. Graph braid groups and right-angled Artin groups. https://arxiv.org/abs/0805.0082

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