Imaging a non-singular rotating black hole at the center of the Galaxy

التفاصيل البيبلوغرافية
العنوان: Imaging a non-singular rotating black hole at the center of the Galaxy
المؤلفون: Lamy, Frédéric, Gourgoulhon, Eric, Paumard, Thibaut, Vincent, Frédéric H.
المصدر: Classical and Quantum Gravity, 2018, Volume 35, Number 11
سنة النشر: 2018
المجموعة: Astrophysics
General Relativity and Quantum Cosmology
مصطلحات موضوعية: General Relativity and Quantum Cosmology, Astrophysics - High Energy Astrophysical Phenomena
الوصف: We show that the rotating generalization of Hayward's non-singular black hole previously studied in the literature is geodesically incomplete, and that its straightforward extension leads to a singular spacetime. We present another extension, which is devoid of any curvature singularity. The obtained metric depends on three parameters and, depending on their values, yields an event horizon or not. These two regimes, named respectively regular rotating Hayward black hole and naked rotating wormhole, are studied both numerically and analytically. In preparation for the upcoming results of the Event Horizon Telescope, the images of an accretion torus around Sgr A*, the supermassive object at the center of the Galaxy, are computed. These images contain, even in the absence of a horizon, a central faint region which bears a resemblance to the shadow of Kerr black holes and emphasizes the difficulty of claiming the existence of an event horizon from the analysis of strong-field images. The frequencies of the co- and contra-rotating orbits at the innermost stable circular orbit (ISCO) in this geometry are also computed, in the hope that quasi-periodic oscillations may permit to compare this model with Kerr's black hole on observational grounds.
Comment: 25 pages, 31 figures; v2: two figures and some clarifications added, version published in CQG
نوع الوثيقة: Working Paper
DOI: 10.1088/1361-6382/aabd97
URL الوصول: http://arxiv.org/abs/1802.01635
رقم الأكسشن: edsarx.1802.01635
قاعدة البيانات: arXiv
الوصف
DOI:10.1088/1361-6382/aabd97