4 papers
Spin-induced Scalar Clouds around Kerr-Newman Black Holes
Guangzhou Guo, Peng Wang, Tianshu Wu +1
Recent studies have demonstrated that a scalar field non-minimally coupled to the electromagnetic field can experience a spin-induced tachyonic instability near Kerr-Newman black h…
Stationary Scalar Clouds around Kerr-Newman Black Holes
Guangzhou Guo, Peng Wang, Tianshu Wu +1
This study investigates scalar clouds around Kerr-Newman black holes within the Einstein-Maxwell-scalar model. Tachyonic instabilities are identified as the driving mechanism for s…
Distinguishing the Observational Signatures of Hot Spots Orbiting Reissner-Nordström Spacetime
Tianshu Wu, Yiqian Chen
This paper delves into observable signatures of hot spots orbiting Reissner-Nordström (RN) black holes and naked singularities. In a RN black hole case, we find two discernible len…
Gravitational Lensing by Transparent Janis-Newman-Winicour Naked Singularities
Deyou Chen, Yiqian Chen, Peng Wang +2
The Janis-Newman-Winicour (JNW) spacetime can describe a naked singularity with a photon sphere that smoothly transforms into a Schwarzschild black hole. Our analysis reveals that…