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arXiv · 1611.02342

Localizing virtual fundamental cycles for semi-perfect obstruction theories

Young-Hoon Kiem
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Abstract

Recently H.-L. Chang and J. Li generalized the theory of virtual fundamental class to the setting of semi-perfect obstruction theory. A semi-perfect obstruction theory requires only the local existence of a perfect obstruction theory with compatibility conditions. In this paper, we generalize the torus localization, the cosection localization and their combination, to the setting of semi-perfect obstruction theory. As an application, we show that the Jiang-Thomas theory of virtual signed Euler characteristic works without the technical quasi-smoothness assumption from derived algebraic geometry.

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Young-Hoon Kiem. 2016-11-07. Localizing virtual fundamental cycles for semi-perfect obstruction theories. https://arxiv.org/abs/1611.02342

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