An infinite presentation for the twist subgroup of the mapping class group of a compact non-orientable surface

Ryoma Kobayashi; Genki Omori

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arXiv · 2009.02022

An infinite presentation for the twist subgroup of the mapping class group of a compact non-orientable surface

Ryoma Kobayashi·Genki Omori

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Abstract

A finite presentation for the subgroup of the mapping class group of a compact non-orientable surface generated by all Dehn twists was given by Stukow. In this paper, we give an infinite presentation for this group, mainly using the presentation given by Stukow and Birman exact sequences on mapping class groups of non-orientable surfaces.

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Ryoma Kobayashi, Genki Omori. 2023-03-09. An infinite presentation for the twist subgroup of the mapping class group of a compact non-orientable surface. https://arxiv.org/abs/2009.02022

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