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arXiv · 1004.2946

Commensurators of surface braid groups

Yoshikata Kida·Saeko Yamagata
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Abstract

We prove that if g and n are integers at least two, then the abstract commensurator of the braid group with n strands on a closed orientable surface of genus g is naturally isomorphic to the extended mapping class group of a compact orientable surface of genus g with n boundary components.

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Yoshikata Kida, Saeko Yamagata. 2011-09-13. Commensurators of surface braid groups. https://doi.org/10.2969/jmsj%2F06341391

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