Probing the near-horizon geometry of black rings

Abstract

In many cases, the near-horizon geometry encodes sufficient information to compute conserved charges of a gravitational solution, including thermodynamic quantities. These charges are Noether charges associated to asymptotic isometries that preserve appropriate boundary conditions at the future horizon. For isolated, compact horizons these charges turn out to be integrable, conserved and finite, and they have been studied in many examples of interest, notably in 3+1 dimensions. In higher dimensions, where the variety of horizon structures is more diverse, it is still possible to apply the same method, although explicit examples have so far been limited to simple topologies. In this paper, we demonstrate that such computations can also be applied to higher-dimensional solutions with event horizons whose spacelike cross sections exhibit non-trivial topology. We provide several explicit examples, with particular focus on the 5-dimensional black ring.