6 papers
Black holes with dark matter halos and a positive cosmological constant: Energy conditions and signatures
Long-Yue Li, Li-Ming Cao, Yungui Gong +3
We study static, spherically symmetric black holes surrounded by dark matter halos in the presence of a positive cosmological constant. Assuming vanishing radial pressure, we deriv…
Analytic Electromagnetic Effective Source for Geodesic Orbit in Schwarzschild Spacetime
Xuchen Lu, Yungui Gong, Bokai Zhang +2
Self-force effects are essential for accurately describing the motion of small bodies in curved spacetime. The effective-source approach privides a promising route to higher-order…
Frequency-domain extended-effective-source gravitational self-force for eccentric Schwarzschild orbits
Xuchen Lu, Yungui Gong, Bokai Zhang +2
Effective-source formulations provide a practical route to gravitational self-force (GSF) calculations when singular retarded fields cannot be handled directly mode by mode. Up to…
The point-particle-limit effective-source approach for computing gravitational self-force in the Lorenz gauge
Chao Zhang, Yungui Gong, Xuchen Lu +1
The traditional effective-source method is hampered by complex analytical expressions and the inherent smoothness limit, which incur high computational costs and complicate impleme…
Signatures of the Israel Junction II: Double Photon Rings in Slowly Rotating Kerr Spacetime with Thin Shell
Long-Yue Li, Li-Ming Cao, Yungui Gong +2
Applying the junction conditions to the slowly rotating Kerr spacetime with a thin shell, when higher order terms in the spin parameter a can be neglected, we find that while the a…
Images and photon regions of continuous photon sphere spacetime
Long-Yue Li, Xia-Yuan Liu, Rong-Gen Cai +2
We study images of spacetimes containing continuous photon spheres (CPS). For a self-gravitating, isotropic, spherically symmetric spacetime with CPS, we find that a thin accretion…