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arXiv · 1202.3557

On Vassiliev invariants of braid groups of the sphere

N. Kaabi·V. V. Vershinin
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Abstract

We construct a universal Vassiliev invariant for braid groups of the sphere and the mapping class groups of the sphere with $n$ punctures. The case of a sphere is different from the classical braid groups or braids of oriented surfaces of genus strictly greater than zero, since Vassiliev invariants in a group without 2-torsion do not distinguish elements of braid group of a sphere.

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N. Kaabi, V. V. Vershinin. 2012-02-16. On Vassiliev invariants of braid groups of the sphere. https://arxiv.org/abs/1202.3557

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