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Updated: Jul 4, 2025

Laboratory Drop Towers for the Experimental Simulation of Dust-aggregate Collisions in the Early Solar System
Published on: June 5, 2014
Dust Collapse in Asymptotic Safety: A Path to Regular Black Holes
Alfio Bonanno1, Daniele Malafarina2, Antonio Panassiti3
1INAF, Osservatorio Astrofisico di Catania, via S.Sofia 78, I-95123 Catania, Italy and INFN, Sezione di Catania, via S.Sofia 64, I-95123 Catania, Italy.
Abstract:
Regular black hole spacetimes are obtained from an effective Lagrangian for quantum Einstein gravity. The interior matter is modeled as a dust fluid, which interacts with the geometry through a multiplicative coupling function denoted as χ. The specific functional form of χ is deduced from asymptotically safe gravity, under the key assumption that the Reuter fixed point remains minimally affected by the presence of matter. As a consequence the gravitational coupling vanishes at high energies. The static exterior geometry of the black hole is entirely determined by the junction conditions at the boundary surface. Consequently, the resulting global spacetime geometry remains devoid of singularities at all times. This outcome offers a new perspective on how regular black holes are formed through gravitational collapse.
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