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arXiv · 2112.08773

New Kind of Echo from Quantum Black Holes

Sreenath K. Manikandan·Karthik Rajeev
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Abstract

We propose that a quantum black hole can produce a new kind of late-time gravitational echoes, facilitated by a near-horizon process analogous to Andreev reflection in condensed matter systems. In comparison to the traditional echo scenarios where the near-horizon region is treated as an ordinary reflector, we argue that, consequent to near-horizon gravitational scattering, this region is better described by an Andreev reflector. Such interactions lead to a novel contribution to gravitational echoes with a characteristic phase difference, an effect which is analogous to how Andreev reflections lead to propagating particle-like and hole-like components with a relative phase in certain condensed matter scenarios. Moreover, this novel contribution to the echo signal encodes information about the `near-horizon quantum state', hence offering a possible new window to probe the quantum nature of black holes.

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BibTeXRIS

Sreenath K. Manikandan, Karthik Rajeev. 2021-12-16. New Kind of Echo from Quantum Black Holes. https://doi.org/10.1103/physrevd.105.064024

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