Black Hole Entropy as Causal Links

Abstract

We model a black hole spacetime as a causal set and count, with a certain definition, the number of causal links crossing the horizon in proximity to a spacelike or null hypersurface $\Sigma$. We find that this number is proportional to the horizon's area on $\Sigma$, thus supporting the interpretation of the links as the ``horizon atoms'' that account for its entropy. The cases studied include not only equilibrium black holes but ones far from equilibrium.

Latex, 20 pages, 4 postscript figures, to appear in a special issue of {\it Foundations of Physics} in honor of Jacob Bekenstein, ``Thirty years of black hole physics'', edited by L. Horwitz

References in corpus (3)

• A Classical Sequential Growth Dynamics for Causal Sets
• Statistical Lorentzian geometry and the closeness of Lorentzian manifolds
• Causal Sets, a Possible Interpretation for the Black Hole Entropy,and Related Topics

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• Horizon Molecules in Causal Set Theory
• A causal perspective on random geometry
• Higher dimensional black holes as constrained systems
• Entanglement Entropy of Disjoint Spacetime Intervals in Causal Set Theory
• A Causal Set Black Hole
• The black hole dynamical horizon and generalized second law of thermodynamics
• Everything You Always Wanted to Know About How Causal Set Theory Can Help with Open Questions in Cosmology, but Were Afraid to Ask
• On the horizon entropy of a causal set
• A sequential growth dynamics for a directed acyclic dyadic graph
• Covariant entropy conjecture and concordance cosmological models
• Black holes and singularities in causal set gravity
• Discrete Black Holes