An explicit section of the Laudenbach exact sequence of the mapping class group of connect sums of $S^2 \times S^1$

Jorge Andres Robinson Arrieta

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arXiv · 2310.13527

An explicit section of the Laudenbach exact sequence of the mapping class group of connect sums of $S^2 \times S^1$

Jorge Andres Robinson Arrieta

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Abstract

Laudenbach proved that the mapping class group of the connect sum of $n$ copies of $S^2 \times S^1$ is an extension of $Out(F_n)$ by a finite group. Brendle-Broaddus-Putman proved that this exact sequence splits. We provide an explicit section $s$ of this split exact sequence.

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Jorge Andres Robinson Arrieta. 2023-10-20. An explicit section of the Laudenbach exact sequence of the mapping class group of connect sums of $S^2 \times S^1$. https://arxiv.org/abs/2310.13527

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