A four-dimensional mapping class group relation

Takahiro Oba

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arXiv · 2106.10914

A four-dimensional mapping class group relation

Takahiro Oba

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Abstract

In the symplectic mapping class group of a $4$-dimensional Weinstein domain, we give a relation between two products of (right-handed) Dehn twists via holomorphic curve techniques. A key ingredient of the construction is a solution to the symplectic isotopy problem on symplectic submanifolds in del Pezzo surfaces. In the appendix, we provide an alternative proof of a relation between a fibered Dehn twist and a product of Dehn twists.

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Takahiro Oba. 2021-06-21. A four-dimensional mapping class group relation. https://arxiv.org/abs/2106.10914

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