Carla Cederbaum

A universal inequality between the angular momentum and horizon area for axisymmetric and stationary black holes with surrounding matter

We prove that for sub-extremal axisymmetric and stationary black holes with arbitrary surrounding matter the inequality 8π|J| < A holds, where J is the angular momentum and A the horizon area of the black hole.

Universal properties of distorted Kerr–Newman black holes

We discuss universal properties of axisymmetric and stationary configurations consisting of a central black hole and surrounding matter in Einstein–Maxwell theory. In particular, we find that certain physical equations and inequalities (involving angular momentum, electric charge and horizon area) are not restricted to the Kerr–Newman solution but can be generalized to the situation where the black hole is distorted by an arbitrary axisymmetric and stationary surrounding matter distribution.

On the center of mass of asymptotically hyperbolic initial data sets

We define the (total) center of mass for suitably asymptotically hyperbolic time-slices of asymptotically anti-de Sitter spacetimes in general relativity. We do so in analogy to the picture that has been consolidated for the (total) center of mass of suitably asymptotically Euclidean time-slices of asymptotically Minkowskian spacetimes (isolated systems). In particular, we unite—an altered version of—the approach based on Hamiltonian charges with an approach based on CMC-foliations near infinity. The newly defined center of mass transforms appropriately under changes of the asymptotic coordinates and evolves in the direction of an appropriately defined linear momentum under the Einstein evolution equations.

Asymptotically flat extensions of CMC Bartnik data

Let

Geometrostatics: The Geometry of Static Space-Times

g

Knoten und Bänder

be a metric on the

Level Sets of the Lapse Function in Static GR

2

A Universal Inequality for Axisymmetric and Stationary Black Holes with Surrounding Matter in the Einstein-Maxwell Theory

-sphere

Explicit Riemannian Manifolds with Unexpectedly Behaving Center of Mass

\mathbb{S}^2

The Newtonian limit of geometrostatics

with positive Gaussian curvature and