Zooming in on fermions and quantum gravity

Understand

We zoom in on the microscopic dynamics for fermions and quantum gravity within the asymptotic-safety paradigm.

• A key finding of our study is the unavoidable presence of a nonminimal derivative coupling between the curvature and fermion fields in the ultraviolet.
• Its backreaction on the properties of the Reuter fixed point remains small for finite fermion numbers within a bounded range.
• This constitutes a nontrivial test of the asymptotic-safety scenario for gravity and fermionic matter, additionally supplemented by our studies of the momentum-dependent vertex flow which indicate the subleading nature of higher-derivative couplings.