The discussion focuses on the concepts of inner and outer horizons in black holes, specifically in the context of rotating black holes, or Kerr black holes. The outer horizon is identified as the event horizon, while the inner horizon is referred to as the Cauchy horizon. The ergosphere is also introduced, which is a region outside the event horizon where objects cannot remain stationary but can escape the black hole's gravitational pull. This explanation clarifies the relationship and functions of these horizons within the framework of black hole physics.
PREREQUISITESAstronomy students, physicists, and researchers interested in black hole mechanics and general relativity will benefit from this discussion.