The inconsistency of state-vector collapse with Hawking's argument for black hole evaporation

Maaneli Derakhshani

It has been noted many times over the past 40 years that the semiclassical Einstein equation is formally inconsistent with state-vector collapse, whether in the context of the standard quantum formalism or dynamical collapse theories. By contrast, Hawking's 1975 argument (and refinements thereof) that black holes evaporate due to semiclassical-gravitational back-reaction of emitted Hawking radiation, takes as its starting point the assumed validity of the semiclassical Einstein equation. In this talk, I will explain exactly how the assumption of state-vector collapse is inconsistent with Hawking's 1975 derivation of the decay rate of the mass of a black hole emitting Hawking radiation, and likewise for refinements of Hawking's derivation that make more explicit use of the semiclassical Einstein equation. Time permitting, I will also show that a many-worlds interpretation of the quantum state in the semiclassical Einstein equation is non-viable. Finally, I will argue from these results that: (1) Hawking's semiclassical argument for black hole evaporation should be rejected, and (2) black hole evaporation due to emitted Hawking radiation has yet to be rigorously established.