Inclusion - Exclusion and Segre
نویسنده
چکیده
Considerations based on the known relation between different characteristic classes for singular hypersufaces suggest that a form of the ‘inclusionexclusion’ principle may hold for Segre classes. We formulate and prove such a principle for a notion closely related to Segre classes. This is used to provide a simple computation of the classes introduced in [Alu], in certain special (but representative) cases.
منابع مشابه
Inclusion-exclusion and Segre Classes
We propose a variation of the notion of Segre class, by forcing a naive `inclusion-exclusion' principle to hold. The resulting class is computationally tractable, and is closely related to Chern-Schwartz-MacPherson classes. We deduce several general properties of the new class from this relation, and obtain an expression for the Milnor class of an arbitrary scheme in terms of this class.
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