The normal closure of a bounding pair map in its mapping class group

Lei Chen; Weiyan Chen; Justin Lanier

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arXiv · 2302.11673

The normal closure of a bounding pair map in its mapping class group

Lei Chen·Weiyan Chen·Justin Lanier

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Abstract

Johnson showed that the normal subgroup of a mapping class group generated by the genus $1$ bounding pair maps is equal to the Torelli group. Generalizing Johnson's result, we give two descriptions of the normal subgroup generated by the genus $n$ bounding pair maps using the Chillingworth and the Casson--Morita invariants.

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Lei Chen, Weiyan Chen, Justin Lanier. 2023-02-22. The normal closure of a bounding pair map in its mapping class group. https://arxiv.org/abs/2302.11673

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