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arXiv · 1501.03864

On CSM classes via Chern-Fulton classes of f-schemes

James Fullwood·Dongxu Wang
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Abstract

The Chern-Fulton class is a generalization of Chern class to the realm of arbitrary embeddable schemes. While Chern-Fulton classes are sensitive to non-reduced scheme structure, they are not sensitive to possible singularities of the underlying support, thus at first glance are not interesting from a singularity theory viewpoint. However, we introduce a class of formal objects which we think of as `fractional schemes', or f-schemes for short, and then show that when one broadens the domain of Chern-Fulton classes to f-schemes one may indeed recover singularity invariants of varieties and schemes. More precisely, we show that for almost all global complete intersections, their Chern-Schwartz-Macpherson classes may be computed via Chern-Fulton classes of f-schemes.

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James Fullwood, Dongxu Wang. 2016-04-29. On CSM classes via Chern-Fulton classes of f-schemes. https://arxiv.org/abs/1501.03864

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