Abstract
We study the interior electrovacuum region of axisymmetric and stationary black holes with surrounding matter and find that there exists always a regular inner Cauchy horizon inside the black hole, provided the angular momentum and charge of the black hole do not vanish simultaneously. In particular, we derive an explicit relation for the metric on the Cauchy horizon in terms of that on the event horizon. Moreover, our analysis reveals the remarkable universal relation , where and denote the areas of event and Cauchy horizon, respectively.
- Received 31 March 2009
DOI:https://doi.org/10.1103/PhysRevLett.102.221102
©2009 American Physical Society