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arXiv · 0706.4421

A presentation for Hilden's subgroup of the braid group

Stephen Tawn
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Abstract

Consider the unit ball, B = D x [0,1], containing n unknotted arcs a_1, ... a_n such that the boundary of each a_i lies in D x {0}. We give a finite presentation for the mapping class group of B fixing the arcs {a_1, ..., a_n} setwise and fixing D x {1} pointwise. This presentation is calculated using the action of this group on a simply-connected complex.

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Stephen Tawn. 2007-10-08. A presentation for Hilden's subgroup of the braid group. https://arxiv.org/abs/0706.4421

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