Summary: For an old evaporating black hole the entanglement wedge of radiation can include an entanglement island that covers a big portion of the black hole interior. We explore a few simple cases where these islands appear and lead to a resolution of apparent information problems. We also discuss how these islands arise through a standard replica trick computation of … Read More
Abstract: It is currently not well understood whether the holographic principle can be applied to asymptotically flat space-times. This talk considers a flat limit of AdS/CFT that leads to a formula relating S-matrix amplitudes in flat space and correlators in a conformal field theory. The limit translates flat physics into the language of conformal theory and holography. As an example, … Read More
Abstract: I will describe effective field theory methods that can be used to study the physics of large-c CFTs in even dimensions. I will argue that an effective field theory of conformal Goldstone modes provides a useful computational and conceptual framework. This generalizes some of the important lessons from studies of the Schwarzian theory in the low-energy SYK model to … Read More
Abstract: The Weak Gravity Conjecture holds that in any consistent theory of quantum gravity, gravity must be the weakest force. This simple proposition has surprisingly nontrivial physical consequences, which in the case of supersymmetric string/M-theory compactifications lead to nontrivial geometric consequences for Calabi-Yau manifolds. In this talk we will describe these conjectured geometric consequences in detail and show how they … Read More
Quantum information science is an emerging frontier of physics which seeks to understand and control quantum systems with a large amount of entanglement and complexity. In this talk, we discuss a novel type of phase transition that arises at this new frontier. We investigate the dynamics of quantum entanglement in a generic quantum many-body system coupled to a noisy environment, … Read More
Abstract: Correlation functions of operators widely separated in time in black hole backgrounds often decay semiclassically. However, for black holes with finite entropy, these correlation functions cannot decay forever. While the non-decaying behavior is erratic and depends sensitively on the microscopic details of the system, certain “averaged” behaviors of these correlation functions follow simple universal patterns, predicted by the Eigenstate … Read More
Abstract: The quantum complexity of a unitary or state is defined as the size of the shortest quantum computation that implements the unitary or prepares the state, and the notion has far-reaching implications spanning computer science, quantum many-body physics, and high energy theory. Complexity growth in time is a phenomenon expected to occur in holographic theories and strongly-interacting many-body systems … Read More
Abstract: According to Harlow and Hayden [arXiv:1301.4504] the task of distilling information out of Hawking radiation appears to be computationally hard despite the fact that the quantum state of the black hole and its radiation is relatively un-complex. We trace this computational difficulty to a geometric obstruction in the Einstein-Rosen bridge connecting the black hole and its radiation. Inspired by … Read More
Two-dimensional Yang-Mills theory at large N has a dual description as a theory of closed strings, making it a useful model for entanglement in gauge/string duality. Definition of entanglement in this theory requires the introduction of an extended Hilbert space, and I will show how this extension fits into the framework of open/closed topological field theory. In the string description, … Read More
abst: We propose a new formula for a bi-partite correlation measure called reflected entropy, in the presence of evaporating black holes, or {\it entanglement islands}. Our new formula is written in terms of the reflected entropy of the bulk matter plus area term of a surface inside the entanglement island. We show that the measure shows interesting phase transition, which … Read More