Motivated by properties of tensor networks, we conjecture that an arbitrary gravitating region a can be assigned a generalized entanglement wedge E⊃a, such that quasi-local operators in E have a holographic representation in the full algebra generated by quasi-local operators in a. The universe need not be asymptotically flat or AdS, and a need not be asymptotic or weakly gravitating. On a static Cauchy surface Σ, we propose that E is the … Read More
Abstract: Recent progress in quantum gravity is underpinned by a sum over spacetimes of different topologies, providing geometric explanations for a variety of quantum properties of black holes. To better understand the Hilbert space interpretation, I will discuss these results from the perspective of the canonical formalism and Lorentzian spacetimes. A simple model demonstrates that topology change can result in a gravitational … Read More
Abstract: The holographic entanglement entropy is a very useful tool in studying the information-theoretic aspects of AdS/CFT, and its efficacy is manifested in the recent black hole page curve calculation. On the other hand, the one-shot entropies, such as the smooth min/max-entropies, are less discussed in AdS/CFT. They are however more fundamental entropy measures from the quantum information perspective and … Read More
How does the bulk Hilbert space of quantum gravity emerge from a boundary theory? I take up this question in the context of the SYK model in the double scaling limit. Berkooz et. al computed correlation functions in this model by summing chord diagrams. By slicing open these chord diagrams, I will explicitly construct the bulk Hilbert space; it resembles that of a … Read More
Abstract: I will describe the parallel transport of modular Hamiltonians encoding entanglement properties of a state. The Berry curvature associated to state-changing parallel transport is the Kirillov-Kostant symplectic form on an associated coadjoint orbit, one which differs appreciably from known Virasoro orbits. I will show that the boundary parallel transport process computes a bulk symplectic form for a Euclidean geometry … Read More
Abstract: In this talk, I will discuss a formulation of holography as approximate quantum error correction using a large code subspace consisting of multiple background geometries. We find corrections to the JLMS formula in novel regimes and explain the presence of such corrections in an approximate error correcting code. The large code subspace allows us to discuss the bulk dual … Read More
Abstract. In finite entropy quantum systems, correlation functions do not decay all the way to zero at late times, but instead hover around a nonzero constant plateau. In the bulk, those same correlation functions evaluated in black hole backgrounds do decay all the way to zero. This apparent tension raises the question of how the bulk gravitational description captures the … Read More
Abstract: We study collisions between shockwaves inside a black hole interior. We give a holographic boundary description of this process in terms of the overlap of two growing perturbations in a shared quantum circuit. The perturbations grow both exponentially as well as ballistically. Due to a competition between different physical effects, the circuit analysis shows dependence on the transverse locations and … Read More
Abstract:Holography has taught us that spacetime is emergent and its properties depend on the entanglement structure of the dual theory. An interesting question is how changes in the entanglement structure affect the bulk dual description. In this talk, I will describe how local projective measurements performed on a subregion A of the boundary theory modify the bulk dual spacetime. The … Read More
Abstract:In this talk, I argue that the Penrose inequality (PI) can be used to constrain low energy theories compatible with AdS/CFT. It is shown that the PI can be violated for minimally coupled scalar fields, and I produce exclusion plots on couplings that respect the PI. I also present numerical evidence that top-down scalar theories and supersymmetric theories respect the … Read More