Black hole interior volume and topology changes in quantum gravity

09.09.2026 11:00 – 12:00

Topology change has been one of the main theme in the study of quantum gravity, as it diagnoses the microscopic spectral statistics of quantum gravity microstates. Yet, it is highly nontrivial to incorporate these quantum effects into the bulk observables such as black hole interior volume. These observables are also interesting from the dual CFT point of view as their close relationship to the Krylov state complexity. In this talk, I describe several distinct ways to define BH interior observables, and explain how they are related to the boundary Krylov complexity. I will particularly emphasize the existence of infinitely many maximal volume timeslices in the presence of baby universe, which leads to an over-complete length basis and a divergence in naive definitions of length. Such divergence disappears once we construct proper complete length basis using Gram-Schmidt orthogonalization. Consequently, we can see the transition to smaller interior BH at late times. As a closely related topic, if time allows, I will also explain a generalization of the ETH matrix model which describes multi-closed universe, whose microscopic Hilbert space is given by H\otimes \bar{H}.

Lieu

Bâtiment: Ecole de Physique

EP234

entrée libre