# Localization of Bott-Chern classes and Hermitian residues

## TL;DR

This paper develops a unified theory of Bott-Chern cohomology, introduces relative versions, and proves a residue theorem for Hermitian vector bundles with applications to singular distributions.

## Contribution

It introduces a unified framework for three related Bott-Chern cohomologies, including localization, duality, and a residue theorem for Hermitian vector bundles.

## Key findings

- Established a long exact sequence linking three Bott-Chern cohomologies.
- Defined cup product and integration in the new cohomology framework.
- Proved a residue theorem for Hermitian vector bundles with compatible connections.

## Abstract

We develop a theory of Cech-Bott-Chern cohomology and in this context we naturally come up with the relative Bott-Chern cohomology. In fact Bott-Chern cohomology has two relatives and they all arise from a single complex. Thus we study these three cohomologies in a unified way and obtain a long exact sequence involving the three. We then study the localization problem of characteristic classes in the relative Bott-Chern cohomology. For this we define the cup product and integration in our framework and we discuss local and global duality homomorphisms. After reviewing some materials on connections, we give a vanishing theorem relevant to our localization. With these, we prove a residue theorem for a vector bundle admitting a Hermitian connection compatible with an action of the non-singular part of a singular distribution. As a typical case, we discuss the action of a distribution on the normal bundle of an invariant submanifold (so-called the Camacho-Sad action) and give a specific example.