Bimetric Truncations for Quantum Einstein Gravity and Asymptotic Safety

Jul, 2009
48 pages
Published in:
  • Annals Phys. 325 (2010) 785-815
e-Print:
Report number:
  • MZ-TH-09-17

Citations per year

2009201320172021202405101520
Abstract: (arXiv)
In the average action approach to the quantization of gravity the fundamental requirement of 'background independence' is met by actually introducing a background metric but leaving it completely arbitrary. The associated Wilsonian renormalization group defines a coarse graining flow on a theory space of functionals which, besides the dynamical metric, depend explicitly on the background metric. All solutions to the truncated flow equations known to date have a trivial background field dependence only, namely via the classical gauge fixing term. In this paper we analyze a number of conceptual issues related to the bimetric character of the gravitational average action and explore a first nontrivial bimetric truncation in the simplified setting of conformally reduced gravity. Possible implications for the Asymptotic Safety program and the cosmological constant problem are discussed in detail.
  • Renormalization group
  • Quantum gravity
  • quantum gravity
  • asymptotic safety
  • cosmological constant
  • renormalization group
  • background field
  • gauge fixing
  • metric
  • effective action