Abstract

Seeking singularity free solutions are important for further understanding black holes in quantum level. Recently, a five-dimensional singularity free black hole/topological star was constructed (Bah and Heidmann in Phys Rev Lett 126:151101, 2021). Through the Kaluza–Klein reduction, an effective four-dimensional static spherically symmetric charged black hole with scalar hair can be obtained. In this paper, we study shadow of this charged black hole with scalar hair in terms of four kinds of observers, i.e., static observers, surrounding observers, freely falling observers, and escaping observers in four-dimensional spacetime. For a spherically symmetric black hole, the shadow is circular for any observer, but the shadow size depends on the motion status of the observer. On the other hand, the effect of plasma is also investigated by a simple model. The radius of the photon sphere depends on the plasma model. Most importantly, we find that the shadow sizes do not monotonically decrease with r in some cases.

Details

Title
Shadow of a charged black hole with scalar hair
Author
Guo, Wen-Di 1 ; Wei, Shao-Wen 1 ; Liu, Yu-Xiao 1 

 Lanzhou University, Lanzhou Center for Theoretical Physics, Key Laboratory of Theoretical Physics of Gansu Province, School of Physical Science and Technology, Lanzhou, People’s Republic of China (GRID:grid.32566.34) (ISNI:0000 0000 8571 0482); Lanzhou University, Institute of Theoretical Physics and Research Center of Gravitation, Lanzhou, People’s Republic of China (GRID:grid.32566.34) (ISNI:0000 0000 8571 0482) 
Pages
197
Publication year
2023
Publication date
Mar 2023
Publisher
Springer Nature B.V.
ISSN
14346044
e-ISSN
14346052
Source type
Scholarly Journal
Language of publication
English
ProQuest document ID
2783522377
Copyright
© The Author(s) 2023. This work is published under http://creativecommons.org/licenses/by/4.0/ (the “License”). Notwithstanding the ProQuest Terms and Conditions, you may use this content in accordance with the terms of the License.