The semiclassical approximation to quantum gravity
Abstract
A detailed review is given of the semiclassical approximation to quantum gravity in the canonical framework. This includes in particular the derivation of the functional Schr\"odinger equation and a discussion of semiclassical time as well as the derivation of quantum gravitational correction terms to the Schr\"odinger equation. These terms are used to calculate energy shifts for fields in De~Sitter space and non-unitary contributions in black hole evaporation. Emphasis is also put on the relevance of decoherence and correlations in semiclassical gravity. The back reaction of non-gravitational quantum fields onto the semiclassical background and the emergence of a Berry connection on superspace is also discussed in this framework.
Cite
@article{arxiv.gr-qc/9312015,
title = {The semiclassical approximation to quantum gravity},
author = {C. Kiefer},
journal= {arXiv preprint arXiv:gr-qc/9312015},
year = {2009}
}
Comments
LATEX, 47 pages, report Freiburg THEP-93/27, to appear in ``Canonical gravity -- from classical to quantum", edited by J. Ehlers and H. Friedrich (Springer, Berlin, 1994)