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arXiv · 1503.08161

Scrambling time from local perturbations of the eternal BTZ black hole

Paweł Caputa·Joan Simón·Andrius Štikonas·Tadashi Takayanagi·Kento Watanabe
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Abstract

We compute the mutual information between finite intervals in two non-compact 2d CFTs in the thermofield double formulation after one of them has been locally perturbed by a primary operator at some time $t_ω$ in the large $c$ limit. We determine the time scale, called the scrambling time, at which the mutual information vanishes and the original entanglement between the thermofield double gets destroyed by the perturbation. We provide a holographic description in terms of a free falling particle in the eternal BTZ black hole that exactly matches our CFT calculations. Our results hold for any time $t_ω$. In particular, when the latter is large, they reproduce the bulk shock-wave propagation along the BTZ horizon description.

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Paweł Caputa, Joan Simón, Andrius Štikonas, Tadashi Takayanagi, Kento Watanabe. 2015-07-12. Scrambling time from local perturbations of the eternal BTZ black hole. https://doi.org/10.1007/jhep08(2015)011

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