Today
  • General Relativity Seminar

    Linearised Second Law for Higher Curvature Gravity and Non-Minimally Coupled Vector Fields

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

    General Relativity Seminar Speaker: Zihan Yan, Cambridge University Title: Linearised Second Law for Higher Curvature Gravity and Non-Minimally Coupled Vector Fields Abstract: Expanding the work of arXiv:1504.08040, we show that black holes obey a second law for linear perturbations to bifurcate Killing horizons, in any covariant higher curvature gravity coupled to scalar and vector fields. The vector […]

  • General Relativity Seminar

    New Well-Posed Boundary Conditions for Semi-Classical Euclidean Gravity

    Virtual

    General Relativity Seminar Speaker: Xiaoyi Liu, UCSB Title: New Well-Posed Boundary Conditions for Semi-Classical Euclidean Gravity Abstract: We consider four-dimensional Euclidean gravity in a finite cavity.  We point out that there exists a one-parameter family of boundary conditions, parameterized by a real constant, where a suitably Weyl-rescaled boundary metric is fixed, and all give a […]

  • General Relativity Seminar

    Quantum Energy Inequalities

    Virtual

    General Relativity Seminar Speaker: Chris Fewster, York University Title: Quantum Energy Inequalities Abstract: Many theorems of mathematical relativity, including singularity and positive mass theorems, include the classical energy conditions among their hypotheses. However, matter described by quantum field theory can violate the classical energy conditions and indeed there is no lower bound to the energy […]

  • General Relativity Seminar

    Real-time observables in horizon thermodynamics

    Virtual

    https://youtu.be/zxjuAlzuW78 General Relativity Seminar Speaker: Albert Law, Stanford Title: Real-time observables in horizon thermodynamics Abstract: Euclidean black hole 1-loop determinants have recently been shown to compute a renormalized thermal canonical partition function for free fields in Lorentzian signature. A key ingredient is a 'quasinormal mode (QNM) character', whose Fourier transform equals the renormalized spectral density of the […]

  • General Relativity Seminar

    An analogue of non-interacting quantum field theory in Riemannian signature

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

    General Relativity Seminar Speaker: Mikhail Molodyk, Stanford Title: An analogue of non-interacting quantum field theory in Riemannian signature Abstract: Recent advances using microlocal tools have led to constructions, for wave operators on various classes of spacetimes, of four distinguished Fredholm inverses which have the singular behavior required of retarded, advanced, Feynman, and anti-Feynman propagators in QFT. Vasy […]

  • Geometry of Generalized Lienard Equations, Contact Geometry and Metriplectic Structure

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

    Speaker: Partha Guha, Khalifa University, Abu Dhabi Title: Geometry of Generalized Lienard Equations, Contact Geometry and Metriplectic Structure Abstract: We start with a self-contained brief review of the construction of non-standard Lagrangian and Hamiltonian structures using the Jacobi Last Multiplier for the (generalized) reduced Lienard equations satisfying Chiellini integrability condition, we then explore its connection […]

  • New Energy Inequality in AdS

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

    General Relativity Seminar Speaker: Diandian Wang, Harvard University Title: New Energy Inequality in AdS Abstract: I will describe evidence for a new energy inequality in asymptotically AdS spacetimes whose conformal boundary contains a spatial circle. It is in some sense analogous but crucially different to the Penrose inequality. In the AdS4 case, this generalizes the […]

  • Quasinormal Corrections to Near-Extremal Black Hole Thermodynamics

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

    General Relativity Seminar Speaker: Daniel Kapec, Harvard Title: Quasinormal Corrections to Near-Extremal Black Hole Thermodynamics Abstract: Recent work on the quantum mechanics of near-extremal non-supersymmetric black holes has identified a characteristic  scaling of the low temperature black hole partition function. This result has only been derived using the path integral in the near-horizon region and relies […]

  • Continuation of solutions of Einstein’s equations

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

    General Relativity Seminar Speaker: Oswaldo Vazquez, Northeastern University Title: Continuation of solutions of Einstein's equations Abstract: Klainerman-Rodnianski improved the continuation criterion for the solutions of Einstein's equations proved by Michael Anderson using Kirchoff-Sobolev type parametrix and geometric Littlewood-Paley theory. Using their technique but a new parametrix we prove a continuation condition in the context of […]

  • Gravitational collapse to extremal Reissner-Nordström and the third law of black hole thermodynamics

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

    General Relativity Seminar Speaker: Christoph Kehle, MIT Title: Gravitational collapse to extremal Reissner-Nordström and the third law of black hole thermodynamics Abstract: In this talk, I will present a proof that extremal Reissner-Nordström black holes can form in finite time in gravitational collapse of charged matter. In particular, this construction provides a definitive disproof of […]

  • Formation of Trapped Surfaces in Geodesic Foliation

    Virtual

    General Relativity Seminar Speaker: Xuantao Chen, Johns Hopkins University Title: Formation of Trapped Surfaces in Geodesic Foliation Abstract: We reprove the formation of trapped surfaces for the Einstein vacuum equation using the incoming geodesic foliation. All previous results, starting with the seminal work of Christodoulou, make use of the double null foliation. In the new […]

  • pp Waves: Quasinormal Modes & Hidden Symmetries of Black Holes

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

    General Relativity Seminar Speaker: Ahmed Seta, Harvard University Title: pp Waves: Quasinormal Modes & Hidden Symmetries of Black Holes Abstract: The spectrum of quasinormal modes of 4D flat space black holes is not analytically tractable, but there are two asymptotic limits where the QNM spectrum is under control: weak damping and strong damping. In this talk, I […]