Quantum-improved Schwarzschild-(A)dS and Kerr-(A)dS spacetimes

Abstract

We discuss quantum black holes in asymptotically safe quantum gravity with a scale identification based on the Kretschmann scalar. After comparing this scenario with other scale identifications, we investigate in detail the Kerr-(A)dS and Schwarzschild-(A)dS space-times. The global structure of these geometries is studied as well as the central curvature singularity and test particle trajectories. The existence of a Planck-sized, extremal, zero temperature black hole remnant guarantees a stable endpoint of the evaporation process via Hawking radiation.

Towards Black-Hole Singularity-Resolution in the Lorentzian Gravitational Path Integral

“…It is worth noting that arguments from quantum gravity have been used to motivate Hayward black holes, see, e.g., [74][75][76]. For instance, the asymptotic-safety-inspired approach to resolve singularities based on a Renormalization Group improvement of classical line elements [57,61,62,77,78] results in an effective Hayward spacetime.…”

Resolving Spacetime Singularities within Asymptotic Safety

“…Similarly, the fuzzball proposal [8,9] provides a mechanism for obtaining regular black holes in the framework of string theory. For the gravitational asymptotic safety program [10][11][12][13][14], the method of renormalization group improvement suggests that black hole singularities may be removed by quantum effects [15,16], also see [17,18] for the current status and further references. The present work takes a key step towards understanding the fate of spacetime singularities within asymptotic safety, based on a first principles computation.…”

Critical Reflections on Asymptotically Safe Gravity

“…Proceeding in a similar way in a gravitational context, it has been a common strategy to retain the dependence of some of the couplings, G k and k say, on the RG scale k and identify the latter with a geometrical quantity or momentum. Based on such RG improvement ideas there is a substantial body of work investigating black-hole physics [341][342][343][344][345][346][347][348][349][350][351][352][353][354][355], gravitational collapse [356][357][358][359][360][361][362], and cosmological scenarios [320,360,[363][364][365][366][367][368][369][370][371][372][373][374][375][376] inspired by Asymptotic Safety. One might expect that this procedure could be justified in some cases where the external scale in question acts as an IR cutoff for fluctuations.…”