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arXiv · 2303.13554

Dark matter spike around Bumblebee black holes

S. Capozziello·S. Zare·D. F. Mota·H. Hassanabadi
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Abstract

The effects of dark matter spike in the vicinity of the supermassive black hole, located at the center of M87 (the Virgo A galaxy), are investigated within the framework of the so-called Bumblebee Gravity. Our primary aim is to determine whether the background of spontaneous Lorentz symmetry breaking has a significant effect on the horizon, ergo-region, and shadow of the Kerr Bumblebee black hole in the spike region. For this purpose, we first incorporate the dark matter distribution in a Lorentz-violating spherically symmetric space-time as a component of the energy-momentum tensors in the Einstein field equations. This leads to a space-time metric for a Schwarzschild Bumblebee black hole with a dark matter distribution in the spike region and beyond. Subsequently, this solution is generalized to a Kerr Bumblebee black hole through the use of the Newman-Janis-Azreg-A\"inou algorithm. Then, according to the available observational data for the dark matter spike density and radius, and the Schwarzschild radius of the supermassive black hole in Virgo A galaxy, we examine the shapes of shadow and demonstrate the influence of the spin parameter $a$, the Lorentz-violating parameter $\ell$ and the corresponding dark matter halo parameters $\rho_{0}$ and $r_{0}$ on the deformation and size of the shadow.

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S. Capozziello, S. Zare, D. F. Mota, H. Hassanabadi. 2023-03-22. Dark matter spike around Bumblebee black holes. https://doi.org/10.1088/1475-7516%2F2023%2F05%2F027

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