Abstract
Spacetime metrics describing ‘non-singular’ black holes are commonly studied in the literature as effective modification to the Schwarzschild solution that mimic quantum gravity effects removing the central singularity. Here we point out that to be physically plausible, such metrics should also incorporate the 1-loop quantum corrections to the Newton potential and a non-trivial time delay between an observer at infinity and an observer in the regular center. We present a modification of the well-known Hayward metric that features these two properties. We discuss bounds on the maximal time delay imposed by conditions on the curvature, and the consequences for the weak energy condition, in general violated by the large transversal pressures introduced by the time delay.
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Notes
It is worth mentioning that the metric proposed by Bardeen in [5] does reproduce the required behaviour of the newtonian potential. On the other hand, as well as all the line elements proposed, it suffers for the time delay problem.
In the numerical plots, we use the value \(\beta =41/10\pi \).
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We kindly acknowledge support from the A*MIDEX project ANR-11-IDEX-0001-02, as well as the Samy Maroun Center For Space, Time and the Quantum.
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De Lorenzo, T., Pacilio, C., Rovelli, C. et al. On the effective metric of a Planck star. Gen Relativ Gravit 47, 41 (2015). https://doi.org/10.1007/s10714-015-1882-8
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DOI: https://doi.org/10.1007/s10714-015-1882-8