Stringy Chern classes of singular varieties
arXiv:math/0407314
Abstract
Motivic integration and MacPherson's transformation are combined in this paper to construct a theory of "stringy" Chern classes for singular varieties. These classes enjoy strong birational invariance properties, and their definition encodes data coming from resolution of singularities. The singularities allowed in the theory are those typical of the minimal model program; examples are given by quotients of manifolds by finite groups. For the latter an explicit formula is proven, assuming that the canonical line bundle of the manifold descends to the quotient. This gives an expression of the stringy Chern class of the quotient in terms of Chern-Schwartz-MacPherson classes of the fixed-point set data.
24 pages; v2: small remarks and one reference added; v3: reviewed esposition, with minor changes and corrections and slightly greater generality in section 5; all main results remain unchanged; to appear in Advances in Math