The Atiyah-Chern Character yields the Semiregularity Map as well as the Infinitesimal Abel-Jacobi Map

Abstract

We construct a general semiregularity map for cycles on a complex analytic or algebraic manifold and show that such semiregularity map can be obtained from the classical tool of the Atiyah-Chern character. The first part of the paper is fairly detailed, deducing the existence and explicit form of a generalized semiregularity map from known results and constructions. We obtain as well a description of the infinitesimal Abel-Jacobi map for smooth cycles as the leading term of this generalized semiregularity map, indicate why for locally complete intersections the appropriate component of our semiregularity map coincides with the one constructed by Bloch, and give applications to embedded deformations and deformations of coherent modules.