Highly accurate numerical solutions to the problem of black holes surrounded by uniformly
rotating rings in axially symmetric, stationary spacetimes are presented. The numerical
methods developed to handle the problem are discussed in some detail. Related Newtonian
problems are described and numerical results provided, which show that configurations can
reach an inner mass-shedding limit as the mass of the central object increases. Exemplary
results for the full relativistic problem for rings of constant density are given and the …

… This paper provides a brief summary of a talk on rings surrounding Black Holes that was
given at the spring meeting 2005 of the German physical society (DPG). A detailed discussion
of the topics covered in the talk can be found in [1]. … The coordinates in which we choose to
formulate the problem of the ring surrounding a Black Hole, the boundary conditions describing
the Black Hole as well as the Einstein equations themselves are all discussed in detail in
[15]. The coordinates are tailored to the symmetries, thus resulting in a two-dimensional …