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arXiv · 1601.04881

Contraction algebra and invariants of singularities

Zheng Hua·Yukinobu Toda
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Abstract

In [7], Donovan and Wemyss introduced the contraction algebra of flop- ping curves in 3-folds. When the flopping curve is smooth and irreducible, we prove that the contraction algebra together with its A_\infty-structure recovers various invariants associated to the underlying singularity and its small resolution, including the derived category of singularities and the genus zero Gopakuma-Vafa invariants.

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Zheng Hua, Yukinobu Toda. 2016-01-19. Contraction algebra and invariants of singularities. https://arxiv.org/abs/1601.04881

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