Max Planck Institute for Gravitational Physics  Albert Einstein Institute (AEI)
Talks by Stephen Green
Format results
Lorenzgauge reconstruction for Teukolsky solutions with sources in electromagnetism
Turbulent gravity in asymptotically AdS spacetimes
Nonlinear backreaction in cosmology
In this talk I discuss the effects of nonlinear backreaction of small scale density inhomogeneities in general relativistic cosmology. It has been proposed that in an inhomogeneous universe, nonlinear terms in the Einstein equation could, if properly averaged and taken into account, affect the large scale Friedmannian evolution of the universe. In particular, it was hoped that these terms might mimic a cosmological constant and eliminate the need for dark energy. After reviewing some of these approaches, and some of their flaws, I will describe a perturbative framework (developed with R.
Superradiant instabilities of asymptotically AdS black holes
Asymptotically AdS spacetimes with reflecting boundary conditions represent a natural setting for studying superradiant instabilities of rotating or charged black holes. In the first part of this talk, I prove that all asymptotically AdS black holes with ergoregions in dimension d ≥ 4 are linearly unstable to gravitational perturbations. This proof uses the canonical energy method of Hollands and Wald in a WKB limit.
Holographic Path to the Turbulent Side of Gravity
holographic path to the turbulent side of gravity

Adam Brown Stanford University

Stephen Green Max Planck Institute for Gravitational Physics  Albert Einstein Institute (AEI)