3 papers
gr-qc2025
A Family of Horizon-penetrating Coordinate Systems for the Schwarzschild Black Hole Geometry with Cauchy Temporal Functions
Christian Röken
We introduce a new family of horizon-penetrating coordinate systems for the Schwarzschild black hole geometry featuring time coordinates that are Cauchy temporal functions for whic…
gr-qc2025
A Quasi-local, Functional Analytic Detection Method for Stationary Limit Surfaces of Black Hole Spacetimes
Christian Röken
We present a quasi-local, functional analytic method to locate and invariantly characterize the stationary limit surfaces of black hole spacetimes with stationary regions. The meth…
astro-ph.SR2024
An exact analytical solution for the weakly magnetized flow around an axially symmetric paraboloid, with application to magnetosphere models
Jens Kleimann, Christian Röken
Rotationally symmetric bodies with longitudinal cross sections of parabolic shape are frequently used to model astrophysical objects, such as magnetospheres and other blunt objects…