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arXiv · 1504.04010

Numerical evidence for universality in the excited instability spectrum of magnetically charged Reissner-Nordström black holes

Shahar Hod
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Abstract

It is well-known that the SU(2) Reissner-Nordström black-hole solutions of the Einstein-Yang-Mills theory are characterized by an infinite set of unstable (imaginary) eigenvalues $\{ω_n(T_{\text{BH}})\}_{n=0}^{n=\infty}$ (here $T_{\text{BH}}$ is the black-hole temperature). In this paper we analyze the excited instability spectrum of these magnetically charged black holes. The numerical results suggest the existence of a universal behavior for these black-hole excited eigenvalues. In particular, we show that unstable eigenvalues in the regime $ω_n\ll T_{\text{BH}}$ are characterized, to a very good degree of accuracy, by the simple universal relation $ω_n(r_+-r_-)={\text{constant}}$, where $r_{\pm}$ are the horizon radii of the black hole.

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Shahar Hod. 2015-04-15. Numerical evidence for universality in the excited instability spectrum of magnetically charged Reissner-Nordström black holes. https://doi.org/10.1140/epjc%2Fs10052-015-3414-9

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