On regular rotating black holes

Understand

Different proposals for regular rotating black hole spacetimes have appeared recently in the literature.

• However, a rigorous analysis and proof of the regularity of this kind of spacetimes is still lacking.
• In this note we analyze rotating Kerr-like black hole spacetimes and find the necessary and sufficient conditions for the regularity of all their second order scalar invariants polynomial in the Riemann tensor.
• We also show that the regularity is linked to a violation of the weak energy conditions around the core of the rotating black hole.