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arXiv · 1605.05268

Realistic Observable in Background-Free Quantum Gravity: the Planck-Star Tunnelling-Time

Marios Christodoulou·Carlo Rovelli·Simone Speziale·Ilya Vilensky
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Abstract

A gravitationally collapsed object can bounce-out from its horizon via a tunnelling process that violates the classical equations in a finite region. Since tunnelling is a non-perturbative phenomenon, it cannot be described in terms of quantum fluctuations around a classical solution and a background-free formulation of quantum gravity is needed to analyze it. Here we use Loop Quantum Gravity to compute the amplitude for this process, in a first approximation. The amplitude determines the tunnelling time as a function of the mass. This is the key information to evaluate the astrophysical relevance of this process. The calculation offers a template and a concrete example of how a background-free quantum theory of gravity can be used to compute a realistical observable quantity.

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Marios Christodoulou, Carlo Rovelli, Simone Speziale, Ilya Vilensky. 2016-05-17. Realistic Observable in Background-Free Quantum Gravity: the Planck-Star Tunnelling-Time. https://doi.org/10.1103/physrevd.94.084035

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