Horizons, Constraints, and Black Hole Entropy

Abstract

Black hole entropy appears to be ``universal''--many independent calculations, involving models with very different microscopic degrees of freedom, all yield the same density of states. I discuss the proposal that this universality comes from the behavior of the underlying symmetries of the classical theory. To impose the condition that a black hole be present, we must partially break the classical symmetries of general relativity, and the resulting Goldstone boson-like degrees of freedom may account for the Bekenstein-Hawking entropy. In particular, I demonstrate that the imposition of a ``stretched horizon'' constraint modifies the algebra of symmetries at the horizon, allowing the use of standard conformal field theory techniques to determine the asymptotic density of states. The results reproduce the Bekenstein-Hawking entropy without any need for detailed assumptions about the microscopic theory.

16 pages, talk given at the "Peyresq Physics 10 Meeting on Micro and Macro structures of spacetime"

References in corpus (11)

• Analogue Gravity
• The fuzzball proposal for black holes: an elementary review
• Relationship between Hawking Radiation and Gravitational Anomalies
• Conformal Field Theory, (2+1)-Dimensional Gravity, and the BTZ Black Hole
• On the Universality of the Hawking Effect
• Quantum Gravity in 2+1 Dimensions: The Case of a Closed Universe
• Dynamics of Asymptotic Diffeomorphisms in (2+1)-Dimensional Gravity
• Horizon constraints and black hole entropy
• Horizon Constraints and Black Hole Entropy
• Black Hole Thermodynamics from Near-Horizon Conformal Quantum Mechanics
• Conformal entropy as a consequence of the properties of stationary Killing horizons

Cited by in corpus (10)

• Scattering of Sound Waves by a Canonical Acoustic Hole
• Effective Conformal Descriptions of Black Hole Entropy
• Black Hole Thermodynamics and Statistical Mechanics
• Covariant Anomalies, Horizons and Hawking Radiation
• Entropy and Temperature From Black-Hole/Near-Horizon-CFT Duality
• Entropy in the Classical and Quantum Polymer Black Hole Models
• Two-Dimensional Quantum Gravity with Boundary
• On horizon constraints and Hawking radiation
• Ergodic Concepts for a Self-Organizing Trivalent Spin Network: A Path to $(2+1)$-dimensional Black Hole Entropy
• Field theory aspects of cosmology and black holes