4 papers
Robust topological invariants of timelike circular orbits for spinning test particles in black hole spacetimes
Yong Song, Jiaqi Fu, Yiting Cen
The spin-curvature coupling in the Mathisson-Papapetrou-Dixon (MPD) formalism induces non-geodesic motion, shifting the orbital parameters of spinning test particles in black hole…
The existence and upper bound for stable photon spheres in static spherically symmetric black holes
Yong Song, Jiaqi Fu, Yiting Cen
In this work, we establish the existence conditions and a universal upper bound on the radius of stable photon spheres (SPS) outside the event horizons of static, spherically symme…
Upper bound on the radius of the innermost stable circular orbit of black holes
Yiting Cen, Yong Song
In this work, we investigate a universal upper bound on the radius of the innermost stable circular orbit (ISCOs) for massive particles in static, spherically symmetric, and asympt…
A unified topological classification of circular orbits for charged particles in black hole spacetimes
Yong Song, Jia Li, Yiting Cen +3
The study of circular orbits offers profound insights into the structure of spacetime around black holes. While the topological properties of these orbits are well-established for…