The beginning of the lecture notes read: Ingemar Bengtsson ANTI-DE SITTER SPACE Fall 1998 Anti-de Sitter space is the maximally symmetric solution of Einstein's equatons with an attractive cosmological constant included; in reality the cosmological constant is certainly not attractive, but it is possible to regard it merely as a kind of regularisation of the long-distance behaviour of gravity. The conformal boundary of asymptotically anti-de Sitter space differs dramatically from that of asymptotically flat spacetimes, and this feature is usually crucial whenever anti-de Sitter space appears in mathematical physics. Notable examples are Friedrich's treatment of isolated systems in GR, the BTZ black holes, and also various studies in supersymmetry and string theory.
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