Index theory, eta forms, and Deligne cohomology
Abstract
Description
The Chern classes of a K-theory class which is represented by a vector bundle with connection admit refinements to Cheeger-Simons classes in Deligne cohomology. In the present paper we consider similar refinements in the case where the classes in K-theory are represented by geometric families of Dirac operators. In low dimensions these refinements correspond to the exponentiated eta-invariant, the determinant line bundle with Quillen metric and Bismut-Freed connection, and Lott's index gerbe with connection and curving. We give a unified treatement of these cases as well as their higher generalizations.
Our main technical tool is a variant of local index theory for Dirac operators of families of manifolds with corners.
Revised version (some arguments expanded and examples added) 147 pages
Revised version (some arguments expanded and examples added) 147 pages