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arXiv · 1703.10053

Finite presentations for spherical/braid twist groups from decorated marked surfaces

Yu Qiu·Yu Zhou
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Abstract

We give a finite presentation for the braid twist group of a decorated surface. If the decorated surface arises from a triangulated marked surface without punctures, we obtain a finite presentation for the spherical twist group of the associated 3-Calabi-Yau triangulated category. The motivation/application is that the result will be used to show that the (principal component of) space of stability conditions on the 3-Calabi-Yau category is simply connected in the sequel.

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Yu Qiu, Yu Zhou. 2021-08-25. Finite presentations for spherical/braid twist groups from decorated marked surfaces. https://doi.org/10.1112/topo.12135

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