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arXiv · 2010.10114

Double bubble plumbings and two-curve flops

Ivan Smith·Michael Wemyss
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Abstract

We discuss the symplectic topology of the Stein manifolds obtained by plumbing two 3-dimensional spheres along a circle. These spaces are related, at a derived level and working in a characteristic determined by the specific geometry, to local threefolds which contain two floppable $(-1,-1)$-curves meeting at a point. Using contraction algebras we classify spherical objects on the B-side, and derive topological consequences including a complete description of the homology classes realised by graded exact Lagrangians.

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Ivan Smith, Michael Wemyss. 2022-12-08. Double bubble plumbings and two-curve flops. https://arxiv.org/abs/2010.10114

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