The Intrinsic Normal Cone For Artin Stacks

Dhyan Aranha; Piotr Pstrągowski

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arXiv · 1909.07478

The Intrinsic Normal Cone For Artin Stacks

Dhyan Aranha·Piotr Pstrągowski

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Abstract

We extend the construction of the normal cone of a closed embedding of schemes to any locally of finite type morphism of higher Artin stacks and show that in the Deligne-Mumford case our construction recovers the relative intrinsic normal cone of Behrend and Fantechi. We characterize our extension as the unique one satisfying a short list of axioms, and use it to construct the deformation to the normal cone. As an application of our methods, we associate to any morphism of Artin stacks equipped with a choice of a global perfect obstruction theory a relative virtual fundamental class in the Chow group of Kresch.

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BibTeX RIS

Dhyan Aranha, Piotr Pstrągowski. 2022-11-11. The Intrinsic Normal Cone For Artin Stacks. https://arxiv.org/abs/1909.07478

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