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Virtual fundamental classes, global normal cones and Fulton's canonical classes

Bernd Siebert
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Abstract

This paper, first written in 1997, aims at a simplified and more elementary construction of algebraic-geometric virtual fundamental classes as defined by Li/Tian and Behrend/Fantechi. We replace the use of Artin stacks in the latter approach by a yoga of cone bundles of possible independent interest. We also observe a formula for virtual fundamental classes involving only the total Chern class of the index bundle and Fulton's canonical class of the moduli space.

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Bernd Siebert. 2005-09-04. Virtual fundamental classes, global normal cones and Fulton's canonical classes. https://arxiv.org/abs/math/0509076

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