Two - dimensional black holes as open strings : A new realization of the ADS / CFT correspondence ∗

We show that weak-coupled two-dimensional dilaton gravity on Anti-de Sitter space can be described by the dynamics of an open string. Neumann and Dirichlet boundary conditions for the string lead to two different realizations of the Anti-de Sitter/Conformal Field Theory correspondence. In particular, in the Dirichlet case the thermodynamical entropy of two-dimensional black holes can be exactly reproduced by counting the string states. 04.70.Dy; 11.25.Pm; 04.50.+h Typeset using REVTEX E–Mail: [email protected] Post office address: Massachusetts Institute of Technology, Marco Cavaglià 6-408, 77 Massachusetts Avenue, Cambridge MA 02139-4307, USA. E-mail: [email protected] This work is supported in part by funds provided by the U.S. Department of Energy (D.O.E.) under cooperative research agreement DE-FC02-94ER40818 and by a FCT grant, contract number BPD/20166/99.