Today

  • Asymptotic geometry of null hypersurface in Schwarzschild spacetime and null Penrose inequality

    CMSA Room G10 CMSA, 20 Garden Street, Cambridge, MA, United States

    https://youtu.be/pHDcEX45YKM General Relativity Seminar Speaker: Pengyu Le (BIMSA) Title: Asymptotic geometry of null hypersurface in Schwarzschild spacetime and null Penrose inequality Abstract: Null Penrose inequality is an important case of the well-known Penrose inequality on a null hypersurface. It conjectures the relation between the area of the outmost marginally trapped surface and the Bondi mass at […]

  • CMSA GR Seminar 11.10.22

    Schwarzschild-like Topological Solitons in Gravity

    Virtual

    https://youtu.be/hhjIPdyIM3U General Relativity Seminar Speaker: Pierre Heidmann (Johns Hopkins) Title: Schwarzschild-like Topological Solitons in Gravity Abstract: We present large classes of non-extremal solitons in gravity that are asymptotic to four-dimensional Minkowski spacetime plus extra compact dimensions. They correspond to smooth horizonless geometries induced by topology in spacetime and supported by electromagnetic flux, which characterize coherent states of quantum gravity. We discuss […]

  • Ringdown and geometry of trapping for black holes

    Hybrid

    General Relativity Seminar Speaker: Semyon Dyatlov (MIT) Title: Ringdown and geometry of trapping for black holes Abstract: Quasi-normal modes are complex exponential frequencies appearing in long time expansions of solutions to linear wave equations on black hole backgrounds. They appear in particular during the ringdown phase of a black hole merger when the dynamics is expected to […]

  • CMSA GR Seminar 12.08.22

    A new proof for the nonlinear stability of slowly-rotating Kerr-de Sitter

    Virtual

    https://youtu.be/jwvkS2A2dL8 General Relativity Seminar Speaker: Allen Fang (Princeton) Title: A new proof for the nonlinear stability of slowly-rotating Kerr-de Sitter Abstract: The nonlinear stability of the slowly-rotating Kerr-de Sitter family was first proven by Hintz and Vasy in 2016 using microlocal techniques. In my talk, I will present a novel proof of the nonlinear stability […]

  • Testing spacetime geometry with images of supermassive compact objects: Current status and the future

    Virtual

    https://youtu.be/ParxdL5gREI General Relativity Seminar Speaker: Prashant Kocherlakota (BHI) Title: Testing spacetime geometry with images of supermassive compact objects: Current status and the future Abstract: Astrophysical black holes (BHs) are expected to be described by the Kerr solution of the Einstein equations. Several frameworks have recently been developed to parametrically deform the Kerr metric in significantly […]

  • CMSA GR Seminar 02.03.23

    Near extremal de Sitter black holes and JT gravity

    Virtual

    https://youtu.be/0gWCm0wmgOY General Relativity Seminar Speaker: Chiara Toldo (Harvard) Title: Near extremal de Sitter black holes and JT gravity Abstract: In this talk I will explore the thermodynamic response near extremality of charged black holes in four-dimensional Einstein-Maxwell theory with a positive cosmological constant. The latter exhibit three different extremal limits, dubbed cold, Nariai and ultracold configurations, with […]

  • CMSA GR Seminar 02.09.23

    Quasinormal modes and Ruelle resonances: mathematician’s perspective

    CMSA Room G10 CMSA, 20 Garden Street, Cambridge, MA, United States

    https://youtu.be/FyJ6TieNQBc General Relativity Seminar Speaker: Maciej Zworski, UC Berkeley Title: Quasinormal modes and Ruelle resonances: mathematician's perspective Abstract: Quasinormal modes of gravitational waves and Ruelle resonances in hyperbolic classical dynamics share many general properties and can be considered "scattering resonances": they appear in expansions of correlations, as poles of Green functions and are associated to […]

  • CMSA GR Seminar 02.16.23

    Quasinormal Modes from Penrose Limits

    CMSA Room G10 CMSA, 20 Garden Street, Cambridge, MA, United States

    https://youtu.be/taeAnXApzg4 General Relativity Seminar Speaker: Kwinten Fransen (UC Santa Barbara) Title: Quasinormal Modes from Penrose Limits Abstract: In this talk, I will explain how to describe quasinormal modes with large real frequencies using Penrose limits. To do so, I first recall relevant aspects of the Penrose limit, and its resulting plane wave spacetimes, as well as quasinormal […]

  • CMSA GR Seminar 02.23.23

    Formation of trapped surfaces in the Einstein-Yang-Mills system

    Virtual

    https://youtu.be/z7q0LGNVPII General Relativity Seminar Speaker: Nikolaos Athanasiou (University of Crete, Greece) Title: Formation of trapped surfaces in the Einstein-Yang-Mills system Abstract: The purpose of this talk is to give an overview of a semi-global existence result and a trapped surface formation results in the context of the Einstein-Yang-Mills system. Adopting a “signature for decay rates” […]

  • CMSA GR Seminar 03.09.23

    Pseudospectrum and black hole quasinormal mode instability: An ultraviolet universality conjecture

    CMSA Room G10 CMSA, 20 Garden Street, Cambridge, MA, United States

    https://youtu.be/teqIIXRJXd4 General Relativity Seminar Speaker: Jose Luis Jaramillo (Bourgogne U.) Title: Pseudospectrum and black hole quasinormal mode instability: an ultraviolet universality conjecture Abstract: Can we measure the ‘effective regularity’ of spacetime from the perturbation of quasi-normal mode (QNM) overtones? Black hole (BH) QNMs encode the resonant response of black holes under linear perturbations, their associated […]

  • CMSA GR Seminar 03.23.23

    New Phases of N=4 SYM

    CMSA Room G10 CMSA, 20 Garden Street, Cambridge, MA, United States

    https://youtu.be/Kt7n_0t6sgo General Relativity Seminar Speaker: Prahar Mitra (University of Cambridge) Title: New Phases of N=4 SYM Abstract: We construct new static solutions to gauged supergravity that, via the AdS/CFT correspondence, are dual to thermal phases in N=4 SYM at finite chemical potential. These solutions dominate the micro-canonical ensemble and are required to ultimately reproduce the microscopic entropy of AdS […]

  • CMSA GR Seminar 03.30.23

    Gravitational perturbations near to extreme Kerr

    CMSA Room G10 CMSA, 20 Garden Street, Cambridge, MA, United States

    https://youtu.be/VdfmeuDoofY General Relativity Seminar Speaker: Alejandra Castro (University of Cambridge) Title: Gravitational perturbations near to extreme Kerr Abstract: Gravitational perturbations of a black hole illustrate the invaluable synergy between theory, experiment, and numerical simulations in general relativity. A recent development in the theory side has been the identification of the relevant degrees of freedom describing the low energy […]