Sergio Hernandez-Cuenca (MIT) “Black Holes at Non-Perturbatively Low Temperatures”
Abstract:At exponentially low temperatures in the black hole entropy, (doubly) non-perturbative effects are not merely important; they dominate. In this talk, I’ll address this regime using the near-extremal sector universally captured by JT-like theories and its matrix integral description. I’ll begin by explaining how the matrix ensemble generically implies a negative divergence at extremality of the annealed entropy traditionally computed … Read More
Chintan Patel (Tata Institute of Fundamental Research/Kavli Institute for Theoretical Physics) “Charged Superradiance in AdS5 x S5 black holes”
Abstract:It has been known since more than a decade that a class of charged black holes in AdS space are unstable to emission of charged particles. There have been many attempts to understand the endpoint of this instability, including the construction of hairy black hole solutions which consist of a condensate of a charged scalar field in the black hole background. … Read More
Zixia Wei (Harvard) “Holographic Dual of Crosscap CFT and Emergent de Sitter Features”
Abstract: I propose a bottom-up correspondence between a CFT defined on 2D non-orientable manifolds, such as the real projective plane (RP2) and the Klein bottle (K2), and AdS3 Einstein gravity with dS2 end-of-the-world branes. In this correspondence, a global dS2 end-of-the-world brane (a quotient by Z2) is described by the unitary time evolution of a crosscap state in the CFT, post-selected … Read More
Mark Van Raamsdonk (UBC) “Cosmology from Holography”
Abstract: I will describe how the standard tools of holography might be used to define microscopic models of big-bang cosmology. I discuss “local” models where a bubble of the cosmological spacetime is embedded in an asymptotically AdS spacetime, and “global” models where the full spacetime is encoded in some auxiliary degrees of freedom. While the gravitational effective field theories arising from holographic models … Read More
Beatrix Muehlmann (IAS) “The complex Liouville string: toward dS”
I will introduce a new 2d gravity/matrix integral duality. The bulk theory is a two-dimensional string theory defined by coupling two copies of Liouville CFT with central charges c = 13 ± is on the worldsheet. We call this string theory the complex Liouville string (CLS). I will argue that the CLS admits a dual description in terms of a … Read More
Joaquin Turiaci (University of Washington) ” “Revisiting Small Black Holes””
Abstract: Black holes with two charges in string theory are singular due to vanishing horizon area at extremality. Two seemingly contradictory resolutions are available in the literature. On one hand, it has been argued that higher-derivative effects create a string-sized extremal horizon. On the other hand, it has been argued that before such a small black hole even forms, there is a transition … Read More
Henry Maxfield (Stanford) “de Sitter JT: a case study for canonical quantum gravity”
I will discuss the quantisation of de Sitter JT gravity in the canonical formalism to illustrate constructions of Hilbert spaces in quantum gravity. Our aim is a description of states which makes spacetime locality manifest with a positive inner product, which is challenging due to the Hamiltonian constraints. The key ideas include representing states either as “invariants” (solutions to the Wheeler-DeWitt … Read More
Adam Brown (Stanford) “The Channel Capacity of a Relativistic String”
I explore the limitations on the capacity of a relativistic channel to transmit power and information that arise because of the finiteness of the transverse speed of light. As a model system, I consider a rope constructed from a fundamental string, for which relativistic invariance is built in. By wiggling one end of the string, both power and information may … Read More