Twenty Years of Debate with Stephen
Leonard Susskind
TL;DR
The paper surveys a long-running debate on information loss in black holes and advocates a new quantum-gravitational paradigm comprising Horizon Complementarity, the Holographic Principle, the UV/IR connection, and microstate counting. Using AdS/CFT as a concrete realization, it argues that bulk physics is encoded on boundaries and that unitarity can be preserved despite horizons, while locality becomes observer-dependent. The discussion extends to de Sitter space and finite-entropy systems, highlighting the breakdown of naive quantum field theory and the necessity of recurrences and boundary-based descriptions. Overall, it emphasizes information conservation for exterior observers and the need to revise notions of locality to reconcile gravity with quantum mechanics.
Abstract
This is my contribution to Stephen Hawking's 60th birthday party. Happy Birthday Stephen!