# Effect of gravitational wave on shadow of a Schwarzschild black hole

Authors
• 1 Qingdao University of Science and Technology, Qingdao, Shandong, 266061, People’s Republic of China , Qingdao (China)
• 2 Hunan Normal University, Changsha, Hunan, 410081, People’s Republic of China , Changsha (China)
• 3 Yangzhou University, Yangzhou, 225009, China , Yangzhou (China)
Type
Published Article
Journal
The European Physical Journal C
Publisher
Springer-Verlag
Publication Date
Jun 08, 2021
Volume
81
Issue
6
Identifiers
DOI: 10.1140/epjc/s10052-021-09287-2
Source
Springer Nature
We have studied the shadows of a Schwarzschild black hole under a special polar gravitational perturbation, which is a particular solution of Einstein equations expanded up to first order. It is shown that the black hole shadow changes periodically with time and the change of shadow depends on the Legendre polynomial order parameter l and the frequency σ\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$\sigma$$\end{document} of gravitational wave. For the odd order of Legendre polynomial, the center of shadow oscillates along the direction which is vertical to equatorial plane. For even l, the center of shadow does not move, but the shadow alternately stretches and squeezes with time along the vertical direction. Moreover, the presence of the gravitational wave leads to the self-similar fractal structures appearing in the boundary of the black hole shadow. We also find that this special gravitational wave has a greater influence on the vertical direction of black hole shadow.