Introdução à Obstrução de Euler Local: dos sólidos platônicos às variedades determinantais

Raphael de Omena Marinho

doi:10.14244/lajm.v4i1.37

Authors

Raphael de Omena Marinho UFC

DOI:

https://doi.org/10.14244/lajm.v4i1.37

Keywords:

teoria de obstrução, variedade singular, campo de vetor, índice

Abstract

The local Euler obstruction was initially defined by MacPherson to address the Deligne and Grothendieck conjecture regarding the existence and uniqueness of Chern classes for singular algebraic varieties. In the context of indices of vector fields, Brasselet and Schwartz characterized this invariant, an approach we will follow in this text. Based on this definition, we also present the Euler obstruction of a function and the Euler obstruction of a map.

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