Event Category: String Seminar

String Seminar:
Tuesdays at 3:40pm on campus

–

Abstract: Recently it has been shown that JT gravity is dual to a hermitian matrix model. This means that JT gravity is not dual to a single boundary theory, as we would expect from higher dimensional examples of AdS/CFT, but rather to an ensemble of theories. In this talk I will present a gravitational theory that interpolates between JT gravity, … Read More

–

Abstract: The Covariant Entropy Bound implies a singularity in the domain of dependence of hyperentropic regions, i.e., regions whose entropy exceeds their boundary area. This extends the Penrose singularity theorem to a large class of compact regions. The quantum version of the bound implies a similar theorem in settings where quantum effects are dominant, such as a black hole after … Read More

–

We review and extend recent progress on the quantum description of near-extremal black holes in the language of effective quantum field theory. With black holes in Einstein-Maxwell theory as the main example, we derive the low energy description of the AdS(2) region from a spacetime point of view. We also give a concise formula for the symmetry breaking scale, we … Read More

–

Streaming link https://berkeley.zoom.us/j/370438207 Abstract: This talk will be a guided tour of some of the essential insights from arXiv:2107.00009. In pure AdS3 gravity, I will present a rigorous bound on boundary reflected entropy in terms of a topological feature of bulk spacetime (the “edge count”), and give an interpretation of the bound in terms of irreducible multipartite entanglement structures in holography. I … Read More

–

Streaming link https://berkeley.zoom.us/j/370438207 Abstract: The late-time, long-distance behaviour of gravitational perturbations of planar AdS black holes is controlled by hydrodynamic quasinormal modes. In the dual CFT these are modes of the conserved currents which control the infra-red dynamics. While the on-shell structure of these modes has been understood for a long-time, we have recently begun to understand how to construct an off-shell … Read More

–

Abstract: I will discuss recent work on a Hayden & Preskill like setup for both maximally chaotic and sub- maximally chaotic quantum field theories. We act on the vacuum with an operator in a Rindler like wedge R and transfer a small subregion I of R to the other wedge. The chaotic scrambling dynamics of the QFT Rindler time evolution reveals … Read More

–

Streaming link https://berkeley.zoom.us/j/370438207   In 2007.07444, it was pointed out that wormholes do not only arise in the replica trick for the von Neumann entropy, but also in the gravitational path integral for extensive quantities like the (quenched) free energy. A replica trick computation of the free energy requires an analytic continuation to zero replicas which is not well understood and appears to … Read More

–

Streaming link https://berkeley.zoom.us/j/370438207   Abstract: In 2016 Harlow taught us that we can understand the Ryu-Takayanagi formula as a feature of quantum error correction. This explained how we should think about both the entanglement wedge and the area term in the formula. However, his analysis only applied in the special case of small code subspaces, in which the entanglement wedge is the same … Read More

–

Abstract:“I will argue that a sufficiently large spatial region in a bubble universe has an entanglement island surrounding it. This island arises due to mandatory collisions with adjacent AdS bubbles. The Unruh radiation from the accelerating domain walls plays a key role in making the bulk entropy term compete with the area term. Based on https://arxiv.org/abs/2106.05271“  Streaming link https://berkeley.zoom.us/j/370438207