2020/03/31 by Kazumasa Okabayashi, Nobuyuki Asaka, Ken-ichi Nakao
Mathematics · Physics and Astronomy · #Artificial intelligence #Astronomy #Astrophysical Phenomena and Observations #Black Holes and Theoretical Physics #Black hole (networking) #Charged black hole #Computer science #Computer security #Event horizon #Extremal black hole #Geodesic #Geometry #Horizon #Mathematics #Merge (version control) #Nonsingular black hole models #Physics #Pulsars and Gravitational Waves Research #Quantum mechanics #Rotating black hole #Silhouette #Spacetime #White hole #astro-ph.HE #gr-qc
paper · pdf · doi:10.1103/physrevd.102.044011
published as Phys. Rev. D 102, 044011 (2020) · 11 pages, 7 figures, published version
arxiv created 2020/08/06 · openalex publication_date 2020/08/06 · arxiv updated 2020/08/12 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/05
The so-called black hole shadow is not a silhouette of a black hole but an image of a collapsing object or a white hole. Hence it is nontrivial whether black hole shadows merge with each other when black holes coalesce with each other. In this paper, by analyzing the null geodesic generators of the event horizon in Kastor-Traschen spacetime which describes a coalescence of black boles, we see that observers who will never see a merger of black hole shadows exist.