Superradiant instability of the Kerr-like black hole in Einstein-bumblebee gravity

Understand

An exact Kerr-like solution has been obtained recently in Einstein-bumblebee gravity model where Lorentz symmetry is spontaneously broken.

• In this paper, we investigate the superradiant instability of the Kerr-like black hole under the perturbation of a massive scalar field.
• We find the Lorentz breaking parameter $L$ does not affect the superradiance regime or the regime of the bound states.
• However, since $L$ appears in the metric and its effect cannot be erased by redefining the rotation parameter $\tilde{a}=\sqrt{1+L}a$, it indeed affects the bound state spectrum and the superradiance.