https://youtu.be/cSgyLwg0v00 General Relativity Seminar Speaker: David Kubiznak (Charles University) Title: Remarkable symmetries of rotating black holes Abstract: It is well known that the Kerr geometry admits a non-trivial Killing tensor and its 'square root' known as the Killing-Yano tensor. These two objects stand behind Carter's constant of geodesic motion as well as allow for separability of test […]
https://youtu.be/xTnSasVv4_0 General Relativity Seminar Speaker: Andras Vasy (Stanford) Title: The Feynman propagator and self-adjointness Abstract: In this talk I will discuss the Feynman and anti-Feynman inverses for wave operators on certain Lorentzian manifolds; these are two inverses which from a microlocal analysis perspective are more natural than the standard causal (advanced/retarded) ones. For instance, for the spectral family […]
https://youtu.be/hmRFX1Js6IA General Relativity Seminar Speaker: Aghil Alaee, Clark University Title: A quasi-local mass in general relativity Abstract: In this talk, we define a new gauge-independent quasi-local mass and energy with respect to the Minkowski spacetime. In contrast to other quasi-local masses, this new quasi-local mass/energy has a quasi-local proof of positivity. This positivity property is for spacelike surfaces with any topology. Moreover, we show […]
General Relativity Seminar Speaker: Jinhua Wang, Xiamen University Title: Noncompact n-dimensional Einstein spaces as attractors for the Einstein flow Abstract: We prove that along with the Einstein flow, any small perturbations of an $n$($n\geq4$)-dimensional, non-compact negative Einstein space with some "non-positive Weyl tensor" lead to a unique and global solution, and the solution will be attracted to […]
General Relativity Seminar Speaker: Sifan Yu, NUS Title: Characteristic Initial Value Problem for the 3D Compressible Euler Equations Abstract: We present the first result for the characteristic initial value problem of the compressible Euler equations in three space dimensions without any symmetry assumption. We allow presence of vorticity and consider any equation of state. Compared […]
General Relativity Seminar Speaker: He Mei, Shenzhen University Title: Asymptotic decay for defocusing semilinear wave equations on Schwarzschild spacetimes Abstract: In this talk, I will present a work on the long time dynamics of solutions to the defocusing semilinear wave equations on the Schwarzschild black hole spacetimes. For sufficiently smooth and localized initial data, we show that the […]
https://youtu.be/G98ywTI82fg General Relativity Seminar Speaker: Nishanth Gudapati, Clark University Title: On Axially Symmetric Perturbations of Kerr Black Hole Spacetimes Abstract: The Kerr black hole stability problem is an important open problem in general relativity. In this talk, I will focus on the role of energy methods in the axisymmetric stability of Kerr black hole spacetimes. […]
General Relativity Seminar Speaker: Yuewen Chen, Tsinghua University Title: High order WENO finite difference scheme for Einstein-Yang-Mills equations Abstract: In this talk, we will show the convergence analysis of the first-order finite difference scheme for static spherically symmetric $SU(2)$ Einstein-Yang-Mills (EYM) equations. We also construct a new WENO scheme for EYM.
General Relativity Seminar Speaker: Jin Jia, Hunan University Title: Scattering Rigidity Problem Abstract: If the asymptotic behavior of a solution to a nonlinear equation is the same as that of a solution to its linearized equation, it is called a scattering solution. Scattering phenomena are widely observed near steady-state solutions of various mathematical physics equations, […]
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 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 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 […]