The renormalization group plays an essential role in many areas of physics, both
conceptually and as a practical tool to determine the long-distance low-energy properties of …

Asymptotic safety is a theoretical proposal for the ultraviolet completion of quantum field
theories, in particular for quantum gravity. Significant progress on this program has led to a …

This book covers recent developments in the covariant formulation of quantum gravity.
Developed in the 1960s by Feynman and DeWitt, by the 1980s this approach seemed to …

We argue that the well-known beta functions of quadratic gravity do not correspond to the
physical dependence of scattering amplitudes on external momenta, and derive the correct …

The asymptotic safety scenario in quantum gravity is reviewed, according to which a
renormalizable quantum theory of the gravitational field is feasible which reconciles …

Adding the terms quadratic in the curvature to the Einstein-Hilbert action renders gravity
renormalizable. This property is preserved in the presence of the most general …

We review and extend in several directions recent results on the “asymptotic safety”
approach to quantum gravity. The central issue in this approach is the search of a Fixed …

We study the nonperturbative renormalization group flow of higher-derivative gravity
employing functional renormalization group techniques. The nonperturbative contributions …

We suggest and briefly review a new sort of superrenormalizable models of higher
derivative quantum gravity. The higher derivative terms in the action can be introduced in …

We recalculate the beta functions of higher-derivative gravity in four dimensions using the
one-loop approximation to an exact renormalization group equation. We reproduce the beta …