Shadow cast by Kerr-like black hole in the presence of plasma in Einstein-bumblebee gravity

Understand

In the Einstein-bumblebee gravity, the Lorentz symmetry is spontaneously broken by a vector field.

• In this paper, we attempt to test the Lorentz symmetry via the observation of the shadow cast by the Kerr-like black hole with or without plasma.
• A novel phenomenon of the Lorentz-violating parameter on the shadow is observed.
• The result shows that when the observer gradually moves from the poles to the equatorial plane, the shadow radius $R_{\rm s}$ firstly decreases and then increases with the Lorentz-violating parameter.