2020/07/31 by Xiaobao Wang, Peng-Cheng Li, Cheng-Yong Zhang +1 · 2 citations
Physics and Astronomy · #Astronomy #Astrophysical Phenomena and Observations #Astrophysics and Cosmic Phenomena #Black hole (networking) #Charged black hole #Classical mechanics #Event horizon #Geodesic #Geodesics in general relativity #Geometry #Horizon #Observer (physics) #Parameter space #Photon #Photon sphere #Physics #Pulsars and Gravitational Waves Research #Quantum mechanics #Schwarzschild radius #Shadow (psychology) #Spacetime #Theoretical physics #Wormhole #gr-qc
paper · pdf · doi:10.1016/j.physletb.2020.135930
published as Phys.Lett.B 811 (2020) 135930 · 5 pages, 4 figures, published in PLB
openalex publication_date 2020/11/06 · arxiv created 2020/11/20 · arxiv updated 2020/11/23 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/05
For dark compact objects such as black holes or wormholes, the shadow size has long been thought to be determined by the unstable photon sphere (region). However, by considering the asymmetric thin-shell wormhole (ATSW) model, we find that the impact parameter of the null geodesics is discontinuous through the wormhole in general and hence we identify novel shadows whose sizes are dependent of the photon sphere in the other side of the spacetime. The novel shadows appear in three cases: (A2) The observer's spacetime contains a photon sphere and the mass parameter is smaller than that of the opposite side; (B1, B2) there' s no photon sphere no matter which mass parameter is bigger. In particular, comparing with the black hole, the wormhole shadow size is always smaller and their difference is significant in most cases, which provides a potential way to observe wormholes directly through Event Horizon Telescope with better detection capability in the future.