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Novel Cauchy-horizon instability

Hideki Maeda·Takashi Torii·Tomohiro Harada
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Abstract

The evolution of weak discontinuity is investigated on horizons in the $n$-dimensional static solutions in the Einstein-Maxwell-scalar-$Λ$ system, including the Reissner-Nordström-(anti) de Sitter black hole. The analysis is essentially local and nonlinear. We find that the Cauchy horizon is unstable, whereas both the black-hole event horizon and the cosmological event horizon are stable. This new instability, the so-called kink instability, of the Cauchy horizon is completely different from the well-known ``infinite-blueshift'' instability. The kink instability makes the analytic continuation beyond the Cauchy horizon unstable.

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Hideki Maeda, Takashi Torii, Tomohiro Harada. 2005-03-10. Novel Cauchy-horizon instability. https://doi.org/10.1103/physrevd.71.064015

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