TY - JOUR
T1 - Quantum gravity on the black hole horizon
AU - Gaddam, Nava
AU - Groenenboom, Nico
AU - 't Hooft, Gerard
N1 - 6 pages
PY - 2022/1
Y1 - 2022/1
N2 - We study scattering on the black hole horizon in a partial wave basis, with an impact parameter of the order of the Schwarzschild radius or less. This resembles the strong gravity regime where quantum gravitational effects appear. The scattering is governed by an infinite number of virtual gravitons exchanged on the horizon. Remarkably, they can all be summed non-perturbatively in $\hbar$ and $\gamma \sim M_{Pl}/M_{BH}$. These results generalise those obtained from studying gravitational backreaction. Unlike in the eikonal calculations in flat space, the relevant centre of mass energy of the collisions is not necessarily Planckian; instead it is easily satisfied, $s \gg \gamma^2 M^2_{Pl}$, for semi-classical black holes. Therefore, infalling observers experience no firewalls. The calculation lends further support to the scattering matrix approach to quantum black holes, and is a second-quantised generalisation of the same.
AB - We study scattering on the black hole horizon in a partial wave basis, with an impact parameter of the order of the Schwarzschild radius or less. This resembles the strong gravity regime where quantum gravitational effects appear. The scattering is governed by an infinite number of virtual gravitons exchanged on the horizon. Remarkably, they can all be summed non-perturbatively in $\hbar$ and $\gamma \sim M_{Pl}/M_{BH}$. These results generalise those obtained from studying gravitational backreaction. Unlike in the eikonal calculations in flat space, the relevant centre of mass energy of the collisions is not necessarily Planckian; instead it is easily satisfied, $s \gg \gamma^2 M^2_{Pl}$, for semi-classical black holes. Therefore, infalling observers experience no firewalls. The calculation lends further support to the scattering matrix approach to quantum black holes, and is a second-quantised generalisation of the same.
UR - https://arxiv.org/abs/2012.02357
U2 - 10.1007/JHEP01(2022)023
DO - 10.1007/JHEP01(2022)023
M3 - Article
SN - 1126-6708
VL - 2022
SP - 1
EP - 12
JO - Journal of High Energy Physics
JF - Journal of High Energy Physics
IS - 1
M1 - 23
ER -