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.