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Analytic study of the null singularity inside spherical charged black holes

Lior M. Burko·Amos Ori
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Abstract

We study analytically the features of the Cauchy horizon (CH) singularity inside a spherically-symmetric charged black hole, nonlinearly perturbed by a self-gravitating massless scalar field. We derive exact expressions for the divergence rate of the blue-shift factors, namely the derivatives in the outgoing direction of the scalar field $Φ$ and the area coordinate $r$. Both derivatives are found to grow along the contracting CH exactly like $1/r$. Our results are valid everywhere along the CH singularity, up to the point of full focusing. These exact analytic expressions are verified numerically.

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Lior M. Burko, Amos Ori. 1997-11-10. Analytic study of the null singularity inside spherical charged black holes. https://doi.org/10.1103/physrevd.57.7084

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