AdS-CFT correspondence and the information paradox - art. no. 104012

The information paradox in the quantum evolution of black holes is studied within the framework of the anti-de Sitter-conformal field theory (AdS-CFT) correspondence. The unitarity of the CFT strongly suggests that all inform ation about an initial state that forms a black hole is returned in the Haw king radiation. The CFT dynamics implies an information retention time of t he order of the black-hole lifetime. This fact determines many qualitative properties of the nonlocal effects that must show up in a semiclassical eff ective theory in the bulk. We argue that no Violations of causality are app arent to local observers, but the semiclassical theory in the bulk duplicat es degrees of freedom inside and outside the event horizon. Nonlocal quantu m effects are required to eliminate this redundancy. This leads to a breakd own of the usual classical-quantum correspondence principle in Lorentzian b lack-hole spacetimes. [S0556-2821(99)02618-1].