Light fermions in quantum gravity

Understand

We study the impact of quantum gravity, formulated as a quantum field theory of the metric, on chiral symmetry in a fermionic matter sector.

• We specifically address the question as to whether metric fluctuations can induce chiral symmetry breaking and bound state formation.
• Our results based on the functional Renormalization Group indicate that chiral symmetry is left intact even at strong gravitational coupling.
• In particular, we find that asymptotically safe quantum gravity where the gravitational couplings approach a non-Gaussian fixed point generically admits universes with light fermions.