The existence of spacetime singularities marks the breakdown of the classical description of gravity within the framework of General Relativity. In this talk I will discuss the modifications of classical black-hole spacetimes induced by Asymptotically Safe Gravity, a particular approach to quantum gravity based on standard Quantum Field Theory, but complemented by the modern, Wilsonian idea of renormalization. A modified black-hole spacetime can be constructed by embedding the running of the gravitational couplings in the classical spacetime geometry. Starting from a classical Schwarzschild black hole, the backreaction effects produced by the running Newton’s coupling are taken into account iteratively. As a key result, if the gravitational renormalization group flow attains a non-trivial fixed point at high energies, the classical singularity is dynamically replaced by a de-Sitter core, and the iteration rapidly converges to a self-consistent black-hole solution, which is devoid of unphysical singularities.
Host: Vincent Moncrief (vincent.moncrief@yale.edu)