Non-perturbative Renormalization for Quantum Gravity - Lecture 2 | Astrid Eichhorn
I will introduce the asymptotic-safety paradigm and how it can make a quantum field theory both ultraviolet complete and predictive. I will discuss mechanisms to generate asymptotic safety, which rely on the effect of quantum fluctuations and will provide examples for theories which are asymptotically safe and do not contain the gravitational interaction. Then, I will review the existing evidence for asymptotic safety in quantum gravity. My main focus will be on results from functional Renormalization Group techniques, but I will also mention results from lattice approaches such as Causal Dynamical Triangulations. Finally, I will discuss the phenomenology of asymptotic safety with a focus on its predictions for particle physics. The key point here will not be effects of quantum gravity at Planckian energies, but an explanation how the interplay of quantum gravity and matter at the Planck scale could result in predictions of the values of some of the couplings in the Standard Model of particle physics and beyond. I will finish with implications of asymptotic safety for the dark sector of the universe.
Suggested reading material:
An introduction to asymptotic safety with non-gravitational and gravitational examples: https://inspirehep.net/literature/169...
An up-to-date review of the interplay of asymptotically safe gravity with matter: https://inspirehep.net/literature/261...
Two introductions to functional Renormalization Group techniques in quantum gravity: https://inspirehep.net/literature/263... and https://inspirehep.net/literature/179...
Critical reflections on asymptotic safety, which address open problems and challenges, but also misconceptions about the approach https://inspirehep.net/literature/179...