journal club on aspects of information, quantum theory, and gravity
29 Feb 2024
We discuss the loss of information in black holes in the context of a globally hyperbolic spacetime that maintains unchanged the whole semiclassical picture except for the ‘‘last evaporation breath’’, which actually pertains to full quantum gravity. Although observers outside the black hole will not have access to information that enters the horizon, no information is lost in the sense it is carried over from one Cauchy surface to the next one (provided the evolution is unitary). In this token, the loss of information in black holes becomes as benign as in the usual classical stellar collapse into a non-evaporating black hole.