How to Recover a Qubit That Has Fallen Into a Black Hole

TL;DR

This paper proposes a method to recover a qubit from a black hole using quantum teleportation principles, relying solely on external measurements of Hawking radiation, thus enabling retrieval without crossing the event horizon.

Contribution

It introduces an algorithm for retrieving a spin-encoded qubit from a black hole via external measurements, advancing quantum information recovery in black hole physics.

Findings

Successful theoretical demonstration of qubit retrieval method

Recovery relies only on external measurements of Hawking radiation

Potential implications for quantum information and black hole complementarity

Abstract

We demonstrate an algorithm for the retrieval of a qubit, encoded in spin angular momentum, that has been dropped into a no-firewall black hole. Retrieval is achieved analogously to quantum teleportation by collecting Hawking radiation and performing measurements on the black hole. Importantly, these methods only require the ability to perform measurements from outside the event horizon.