Trapped photon region in the phase space of sub-extremal Kerr-Newman and Kerr-Sen spacetimes
Abstract
We analyse the geometry and topology of the trapped photon region in the domain of outer communication of sub-extremal Kerr-Newman and Kerr-Sen spacetimes. Specifically, we show that its projection to the (co-)tangent bundle forms a five-dimensional submanifold with topology $SO(3)\times \mathbb{R}^2$ in each setup. The proof adapts the method of Cederbaum and Jahns for sub-extremal Kerr spacetime.
Fields of Study & Subjects
Black Holes and Theoretical Physics
Relativity and Gravitational Theory
Astrophysical Phenomena and Observations
Publication details
- Journal / source
- arXiv (Cornell University)
- Publication date
- 4 February 2026
- Document type
- Preprint