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arXiv · 1811.08480

Symmetric semi-perfect obstruction theory revisited

Yunfeng Jiang
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Abstract

In this paper we survey some results on the symmetric semi-perfect obstruction theory on a Deligne-Mumford stack $X$ constructed by Chang-Li, and Behrend's theorem equating the weighted Euler characteristic of $X$ and the virtual count of $X$ by symmetric semi-perfect obstruction theories. As an application, we prove that Joyce's d-critical scheme admits a symmetric semi-perfect obstruction theory, which can be applied to the virtual Euler characteristics by Jiang-Thomas.

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Yunfeng Jiang. 2018-11-20. Symmetric semi-perfect obstruction theory revisited. https://arxiv.org/abs/1811.08480

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