eng
Max Planck Institute for Gravitational Physics (Albert Einstein Institute)
Living Reviews in Relativity
1433-8351
2006-12-01
9
5
10.12942/lrr-2006-5
lrr-2006-5
article
The Asymptotic Safety Scenario in Quantum Gravity
Max Niedermaier
1
Martin Reuter
2
Laboratoire de Mathematiques et Physique Theorique, CNRS/UMR 6083, Université de Tours, Parc de Grandmont, 37200 Tours, France
Institute of Physics, University of Mainz, Staudingerweg 7, 55099 Mainz, Germany
The asymptotic safety scenario in quantum gravity is reviewed, according to which a renormalizable quantum theory of the gravitational field is feasible which reconciles asymptotically safe couplings with unitarity. The evidence from symmetry truncations and from the truncated flow of the effective average action is presented in detail. A dimensional reduction phenomenon for the residual interactions in the extreme ultraviolet links both results. For practical reasons the background effective action is used as the central object in the quantum theory. In terms of it criteria for a continuum limit are formulated and the notion of a background geometry self-consistently determined by the quantum dynamics is presented. Self-contained appendices provide prerequisites on the background effective action, the effective average action, and their respective renormalization flows.
http://www.livingreviews.org/lrr-2006-5
quantum gravity