Andreev reflecting black holes: a black hole analogy in solid state.

We present a microscopic quantum description for Hawking radiation as analogous to Andreev mode conversions from a superconductor/normal metal interface. Our approach, extending our previous proposals [PRD 96, 124011 (2017), PRD 98, 124043 (2018)], provides a manifestly unitary description for a black hole in its late stages of the evaporation process, where it accepts collapsing matter by pairing them with the infalling Hawking quantum into a Bardeen-Cooper-Schrieffer like quantum ground state. The quantum information encoded in the collapsing matter is Andreev reflected in the outgoing modes, resolving the quantum information paradox. Our resolution is similar to the Horowitz-Maldacena black hole final state proposal, where the quantum information is preserved by the black hole applying a final boundary condition at its singularity. The microscopic details we present suggests a possible mechanism by which the quantum final state proposal may emerge, devoid of possibly unphysical computational enhancements resulting from a final state projection.

Journal reference: Manikandan, S. K., & Jordan, A. N. (2020). Black holes as Andreev reflecting mirrors. Physical Review D, 102(6), 064028.