Title:  

Quantum Superposition Of Black Hole Evaporations

Abstract: 

We revisit Hawking’s black hole evaporation process, allowing a quantum superposition of black

hole masses. The Hawking particles created inside the black hole are assumed to annihilate with

the black hole matter. Since the Hawking particles have an undetermined energy, the black hole

evolves into a superposition of being fully evaporated and not fully evaporated. In the branches of

the superposition where the matter is fully evaporated, the outgoing Hawking particles encode the

initial state of the black hole matter. In the branches where the black hole is not fully evaporated,

more Hawking particle pairs continue to be created. We model this branch-dependent pair creation

with controlled unitaries, which take into account the back-reaction of the radiation emission on

the black hole state. With every burst of radiation the probability of the full annihilation strictly

increases, until the black hole is (asymptotically) fully evaporated in every branch of the quantum

superposition. In this model the evaporation is unitary and the initial state can in principle be

recovered from the radiation.