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arXiv · 1112.6001

Semiregularity via derived deformation theory

J. P. Pridham
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Abstract

We realise Buchweitz and Flenner's semiregularity map (and hence a fortiori Bloch's semiregularity map) as the tangent of a morphism of derived moduli functors. An immediate consequence is that it annihilates all obstructions (not just curvilinear ones) globally. This proves Bloch's semiregularity conjecture and establishes a global reduced obstruction theory.

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J. P. Pridham. 2012-08-16. Semiregularity via derived deformation theory. https://arxiv.org/abs/1112.6001

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