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arXiv · 1212.6944

Boundary unitarity and the black hole information paradox

Ted Jacobson
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Abstract

Both AdS/CFT duality and more general reasoning from quantum gravity point to a rich collection of boundary observables that always evolve unitarily. The physical quantum gravity states described by these observables must be solutions of the spatial diffeomorphism and Wheeler-deWitt constraints, which implies that the state space does not factorize into a tensor product of localized degrees of freedom. The "firewall" argument that unitarity of black hole S-matrix implies the presence of a highly excited quantum state near the horizon is based on such a factorization, hence is not applicable in quantum gravity. In fact, there appears to be no conflict between boundary unitarity and regularity of the event horizon.

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Ted Jacobson. 2012-12-31. Boundary unitarity and the black hole information paradox. https://doi.org/10.1142/s0218271813420029

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