论文标题
旋转肮脏的黑洞及其阴影
Rotating dirty black hole and its shadow
论文作者
论文摘要
在本文中，我们研究了暗物质对质量$ M $的Kerr黑洞的效果。该度量是使用Newman-Janis算法得出的，该算法的种子度量源自Schwarzschild黑洞，该黑洞被带有质量$ M $和厚度$ΔR_{S} $的暗物质的球形壳包围。还用三种不同条件的分段质量函数来描述种子度量。专门研究观察者位于暗物质壳内部的非平凡情况，我们分析了黑洞环境的有效质量如何影响基本的黑洞特性。需要在旋转黑洞附近的高浓度的暗物质，以使地平线，甲环和光子球半径上有相当大的偏差。然而，即使在非常低的暗物质密度下，时间样的大地测量也会显示出对偏差的更高敏感性。此外，还证明，通过Penrose工艺提取能量的位置保持不变。通过在质量函数中描述暗物质分布的方式，以及如何为Kerr黑洞定义阴影半径的复杂性，从而导致$ΔR_{s} $的分析表达式作为明显的暗物质效应的条件，这仍然不便。
In this paper, we examine the effect of dark matter to a Kerr black hole of mass $m$. The metric is derived using the Newman-Janis algorithm, where the seed metric originates from the Schwarzschild black hole surrounded by a spherical shell of dark matter with mass $M$ and thickness $Δr_{s}$. The seed metric is also described in terms of a piecewise mass function with three different conditions. Specializing in the non-trivial case where the observer resides inside the dark matter shell, we analyzed how the effective mass of the black hole environment affects the basic black hole properties. A high concentration of dark matter near the rotating black hole is needed to have considerable deviations on the horizons, ergosphere, and photonsphere radius. The time-like geodesic, however, shows more sensitivity to deviation even at very low dark matter density. Further, the location of energy extraction via the Penrose process is also shown to remain unchanged. With how the dark matter distribution is described in the mass function, and the complexity of how the shadow radius is defined for a Kerr black hole, deriving an analytic expression for $Δr_{s}$ as a condition for notable dark matter effects to occur remains inconvenient.
