  The Reeh-Schlieder theorem, with the time-slice axiom of quantum field
theory, may be used to recover the information which falls into a black hole.
Analyticity of quantum fields in states with finite energy plays the crucial
role. In AdS spacetime, our argument based on the Reeh-Schlieder theorem is
consistent with the argument that there is no information loss because of the
AdS/CFT correspondence.
