English

Global Chern currents of coherent sheaves and Baum Bott currents

Complex Variables 2024-04-24 v1 Algebraic Geometry Differential Geometry

Abstract

We provide global extensions of previous results about representations of characteristic classes of coherent analytic sheaves and of Baum-Bott residues of holomorphic foliations. We show in the first case that they can be represented by currents with support on the support of the given coherent analytic sheaf, and in the second case, by currents with support on the singular set of the foliation. In previous works, we have constructed such representatives provided global resolutions of the appropriate sheaves existed. In this article, we show that the definition of Chern classes of Green and the associated techniques, which work on arbitrary complex manifolds without any assumption on the existence of global resolutions, may be combined with our previous constructions to yield the desired representatives. We also prove a transgression formula for such representatives, which is new even in the case when global resolutions exist. More precisely, the representatives depend on local resolutions of the sheaf, and on choices of metrics and connections on these bundles, i.e., the currents for two different choices differ by a current of the form dNdN, where NN is an explicit current, which in the first case above has support on the support of the given coherent analytic sheaf, and in the second case above has support on the singular set of the foliation.

Keywords

Cite

@article{arxiv.2404.14585,
  title  = {Global Chern currents of coherent sheaves and Baum Bott currents},
  author = {Lucas Kaufmann and Richard Lärkäng and Elizabeth Wulcan},
  journal= {arXiv preprint arXiv:2404.14585},
  year   = {2024}
}

Comments

27 pages