**Jan Ambjorn, Utrecht University**

CDT and asymptotic safety

CDT is a lattice regularization of quantum gravity. The phase structure of the lattice theory is discussed and a candidate UV fixed point located.

**Alfio Bonanno, INAF, Catania**

The mass-inflation phenomenon in the asymptotic safety scenario

**John Joseph M. Carrasco, UCLA**

Perturbative cancellations in gravity theories

I will present recent results through four loops demonstrating that the maximally supersymmetric (N=8) generalization of gravity is surprisingly well behaved in the ultraviolet as a result of unexpected cancellations between contributing terms. These cancellations first manifest at one loop in the form of the "no-triangle property," with all-loop order implications through unitarity. I will conclude by discussing similar novel cancelations identified in pure Einstein gravity, at one loop, which suggest a possible explanation for the unexpectedly tame high energy behavior of N=8 supergravity beyond the limited UV protection of supersymmetry.

**Holger Gies, ITP, Jena University**

Mechanisms of Asymptotic Safety

**Renate Loll, Utrecht University**

Nonperturbative Insights from Causal Dynamical Triangulations

**Max Niedermaier, Tours University**

Gravitational fixed points and asymptotic safety from perturbation theory

**Christoph Rahmede, ****Jena University**

**Renormalization Group Flow in Scalar-Tensor Theories**

**Martin Reuter, Mainz University**

Gravitational average action and asymptotic safety: past and future

**Vincent Rivasseau, Université Paris-Sud XI, Orsay**

A New Mechanism for Asymptotic Safeness

**Frank Saueressig, Mainz University**

Exploring the Theory Space of Asymptotically Safe Quantum Gravity

**Michael Scherer, ITP, Jena University **

A mechanism for Asymptotic Safety of chiral Yukawa systems

We will discuss Weinberg's idea of asymptotic safety for a chiral Yukawa system with a U(N_L)_L x U(1)_R symmetry in a leading-order derivative expansion using nonperturbative functional RG equations. As a toy model sharing important features with the standard model we explicitely discuss N_L=10 for which we find a non-Gaussian fixed point and compute its critical exponents. We observe a reduced hierarchy problem and obtain predictions for the toy Higgs and the toy top mass.

**Lee Smolin, Perimeter Institute**

Asymptotic safety and deformed symmetry

I review work on asymptotic safety in quantum gravity in a 1/N expansion. I highlight the result that the scaling behavior governed by the non-trivial fixed point must be characterized by a scaling dimension less than four. Otherwise a Weyl curvature squared counterterm is required, that renders the theory unstable. This reduced scaling dimension then implies that Lorentz invariance is either broken or deformed, and this is transmitted to the matter sector. However, there are strong constraints on breaking of Lorentz invariance at the Planck scale due to the absence of birefringence of photons. The present constraints on deforming Lorentz invariance are, however, just at the Planck scale. I will then review semiclassical quantum gravity arguments that Lorentz symmetry is deformed.

**Arkady Tseytlin, Imperial College, London**

Comments on UV divergences in quantum gravity

**Gian Paolo Vacca, Bologna University**

Quantum Gravitational Corrections to Matter: A Running Controversy

**B.F.L. Ward, Baylor University**

Asymptotic Safety and Resummed Quantum Gravity

In Weinberg’s asymptotic safety approach to quantum gravity, one has a finite dimensional critical surface for a UV stable fixed point to generate a theory of quantum gravity with a finite number of physical parameters. The task is to demonstrate how this fixed point behavior actually arises. We argue that, in a recently formulated extension of Feynman’s original formulation of the theory, which we have called resummed quantum gravity, we recover this fixed-point UV behavior from an exact re-arrangement of the respective perturbative series. We argue that the results we obtain are consistent both with the exact field space Wilsonian renormalization group results of Reuter and Bonanno and with recent Hopf-algebraic Dyson-Schwinger renormalization theory results of Kreimer. We calculate the first "first principles" predictions of the respective dimensionless gravitational and cosmological constants and argue that they support the Planck scale cosmology advocated by Bonanno and Reuter as well. Comments on the prospects for actually predicting the currently observed value of the cosmological constant are also given.

**Steven Weinberg, University of Texas, Austin**

Prospects for Asymptotic Safety

**Omar Zanusso, SISSA**

Asymptotic safety in the nonlinear sigma models and gravity

**Jean Zinn-Justin, CEA, Saclay**

Asymptotic safety: a review

I shall review on field theory examples, the meaning of the concept of asymptotic safety in the context of low energy effective field theories.