POSSIBLE RESOLUTION OF THE BLACK-HOLE INFORMATION PUZZLE

The problem of information loss is considered under the assumption that the process of black hole evaporation terminates in the decay of the black hole interior into a baby universe. We show that such theories can be decomposed into superselection sectors labeled by eigenvalues of the third-quantized baby universe field operator, and that scattering is unitary within each superselection sector. This result relies crucially on the quantum-mechanical variability of the decay time. It is further argued that the decay rate in the black hole rest frame is necessarily proportional to etot-S, where Stot is the total entropy produced during the evaporation process, entailing a very long-lived remnant. © 1994 The American Physical Society.