Princeton University Gravity Initiative Seminar Series

Abstract: Classical black holes obey laws of thermodynamics, which suggests that quantum black holes are complicated statistical systems. This supposition has been validated in specific examples using string theory and holography, but a general understanding of the statistical properties of black holes remains an important problem. Recent work has made it possible to find a “middle ground” between the coarse thermodynamic properties of black holes and a fine-grained understanding of their quantum microstates — semiclassical black holes admit a Boltzmann-Gibbs-style statistical description that is weaker than a complete quantum description, but is stronger than a simple description in terms of thermodynamics. This colloquium-style talk will review the work that made this description possible, and explain how tools from operator algebras let us quantitatively compare the number of microstates in different black hole ensembles, even if the absolute number of microstates cannot be accessed without a complete theory of quantum gravity. Based in part on 2404.16098 with Akers.