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arXiv · 1804.04753

Scaling and Universality in Extremal Black Hole Perturbations

Samuel E. Gralla·Peter Zimmerman
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Abstract

We show that the emergent near-horizon conformal symmetry of extremal black holes gives rise to universal behavior in perturbing fields, both near and far from the black hole horizon. The scale-invariance of the near-horizon region entails power law time-dependence with three universal features: (1) the decay off the horizon is always precisely twice as fast as the decay on the horizon; (2) the special rates of $1/t$ off the horizon and $1/\sqrt{v}$ on the horizon commonly occur; and (3) sufficiently high-order transverse derivatives grow on the horizon (Aretakis instability). The results are simply understood in terms of near-horizon ($\mathrm{AdS}_2$) holography. We first show how the general features follow from symmetry alone and then go on to present the detailed universal behavior of scalar, electromagnetic, and gravitational perturbations of $d$-dimensional electrovacuum black holes.

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Samuel E. Gralla, Peter Zimmerman. 2018-07-11. Scaling and Universality in Extremal Black Hole Perturbations. https://doi.org/10.1007/jhep06(2018)061

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