English

On the Chern classes of singular complete intersections

Algebraic Geometry 2019-11-20 v1

Abstract

We consider two classical extensions for singular varieties of the usual Chern classes of complex manifolds, namely the total Schwartz-MacPherson and Fulton-Johnson classes, cSM(X)c^{SM}(X) and cFJ(X)c^{FJ}(X). Their difference (up to sign) is the total Milnor class M(X){\mathcal M}(X), a generalization of the Milnor number for varieties with arbitrary singular set. We get first Verdier-Riemann-Roch type formulae for the total classes cSM(X)c^{SM}(X) and cFJ(X)c^{FJ}(X), and use these to prove a surprisingly simple formula for the total Milnor class when XX is defined by a finite number of local complete intersection X1,,XrX_1,\cdot \ldots \cdot,X_r in a complex manifold, satisfying certain transversality conditions. As applications we obtain a Parusi\'{n}ski-Pragacz type formula and an Aluffi type formula for the Milnor class, and a description of the Milnor classes of XX in terms of the global L\^e classes of the XiX_i.

Keywords

Cite

@article{arxiv.1909.01117,
  title  = {On the Chern classes of singular complete intersections},
  author = {Roberto Callejas-Bedregal and Michelle Morgado and Jose Seade},
  journal= {arXiv preprint arXiv:1909.01117},
  year   = {2019}
}

Comments

Accepted for publication in the Journal of Topology

R2 v1 2026-06-23T11:03:57.971Z