Speaker
Description
Quantum scale symmetry arises at fixed points of the flow of couplings as an exact symmetry. Particle scale symmetry is related to the second order character of the vacuum electroweak phase transition. It makes the gauge hierarchy technically natural.
In the context of quantum gravity even the tiny dimensionless ratio Fermi scale over Planck scale may be explained. Gravity scale symmetry is associated to the ultraviolet fixed point of asymptotic safety that makes quantum gravity a non-perturbatively renormalizable quantum field theory. New predictions for particle physics, as the mass of the Higgs boson, become possible. In cosmology, the presence of a fixed point is at the origin of the almost scale invariant primordial fluctuation spectrum. Spontaneously broken scale symmetry associated to an infrared fixed point can explain the smallness of the cosmological „constant“ in the form of dynamical dark energy. We relate these different facets of scale symmetry.