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Black Hole Singularity Resolution in Unimodular Gravity from Unitarity
Steffen Gielen1, Lucía Menéndez-Pidal2
1University of Sheffield, School of Mathematical and Physical Sciences, Hicks Building, Hounsfield Road, Sheffield S3 7RH, United Kingdom.
Abstract:
We study the quantum dynamics of an interior planar anti-de Sitter black hole, requiring unitarity in the natural time coordinate conjugate to the cosmological "constant of motion" appearing in unimodular gravity. Both the classical singularity and the horizon are replaced by a nonsingular highly quantum region; semiclassical notions of spacetime evolution are only valid in an intermediate region. For the singularity, our results should be applicable to general black holes: unitarity in unimodular time always implies singularity resolution.
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