2018/11/16 by J. Bardeen, Bardeen, James M. · 1 citation
Physics and Astronomy · #Black Holes and Theoretical Physics #Noncommutative and Quantum Gravity Theories #Quantum Electrodynamics and Casimir Effect
paper · pdf · doi:10.48550/arxiv.1811.06683
There have been a number of suggestions that the r = 0 singularity of a\nspherically symmetric (uncharged) evaporating black hole can be circumvented by\na quantum transition to a white hole, which eventually releases all trapped\nquantum information, consistent with overall unitary evolution of the quantum\nfields. Some of these scenarios rely on loop quantum gravity to impose a\nminimum area of two-spheres, but are quite vague on how to deal with black hole\nevaporation, particularly its endpoint. In this paper I present a rather\ncomplete toy model for the evolution of the geometry and the effective\nstress-energy tensor derived from the geometry via the classical Einstein\nequations. Modifications of the Schwarzschild geometry once the formation of\nthe black hole is complete are very small outside regions of high curvature,\nand the curvature never becomes super-Planckian. The evolution of the white\nhole is roughlythe time reverse of the formation and evaporation of the black\nhole. The mass of the white hole increases as it gradually emits the negative\nenergy that flowed into the black hole during its evaporation until the matter\nand radiaton that collapsed to form the black hole emerges and the white hole\ndisappears. I consider the compatibility of the model with some of the quantum\nenergy condition proposed in the literature, and the implications for the\ninterpretation of black hole entropy.\n