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Title: Improved effective dynamics of loop-quantum-gravity black hole and Nariai limit
Abstract

We propose a new model of the spherical symmetric quantum black hole in the reduced phase space formulation. We deparametrize gravity by coupling to the Gaussian dust which provides the material coordinates. The foliation by dust coordinates covers both the interior and exterior of the black hole. After the spherical symmetry reduction, our model is a 1 + 1 dimensional field theory containing infinitely many degrees of freedom. The effective dynamics of the quantum black hole is generated by an improved physical HamiltonianHΔ. The holonomy correction inHΔis implemented by theμ¯-scheme regularization with a Planckian area scale Δ (which often chosen as the minimal area gap in loop quantum gravity). The effective dynamics recovers the semiclassical Schwarzschild geometry at low curvature regime and resolves the black hole singularity with Planckian curvature, e.g.RμνρσRμνρσ∼ 1/Δ2. Our model predicts that the evolution of the black hole at late time reaches the charged Nariai geometry dS2×S2with Planckian radiiΔ. The Nariai geometry is stable under linear perturbations but may be unstable by nonperturbative quantum effects. Our model suggests the existence of quantum tunneling of the Nariai geometry and a scenario of black-hole-to-white-hole transition.

 
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Award ID(s):
1912278
NSF-PAR ID:
10361710
Author(s) / Creator(s):
;
Publisher / Repository:
IOP Publishing
Date Published:
Journal Name:
Classical and Quantum Gravity
Volume:
39
Issue:
3
ISSN:
0264-9381
Page Range / eLocation ID:
Article No. 035011
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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