Equivariant Hirzebruch class for singular varieties
Abstract
The Hirzebruch class of a complex manifold X is a formal combination of Chern characters of the sheaves of differential forms multiplied by the Todd class. The related -genus admits a generalization for singular complex algebraic varieties. The equivariant version of the Hirzebruch class can be developed as well. The general theory applied in the situation when a torus acts on a singular variety allows to apply powerful tools as the Localization Theorem of Atiyah and Segal for equivariant K-theory and Berline-Vergne formula for equivariant cohomology. We obtain a meaningful invariant of a germ of singularity. When it is made explicit it turns out to be just a polynomial in characters of the torus. We discuss a relation of the properties of a singularity germ with its local Hirzebruch class. The issue of positivity of coefficients in a certain expansion remains mysterious. The quotient singularities, toric singularities, the singularities of Schubert varieties are of special interest.
Cite
@article{arxiv.1308.0788,
title = {Equivariant Hirzebruch class for singular varieties},
author = {Andrzej Weber},
journal= {arXiv preprint arXiv:1308.0788},
year = {2015}
}
Comments
38 pages, 3 figures