论文标题
动态光子球和时间在黑洞周围带有暂时增生的阴影
Dynamical photon sphere and time evolving shadow around black holes with temporal accretion
论文作者
论文摘要
光子球被称为塑造黑洞阴影的几何结构。对于静态或固定的黑洞空位，例如Schwarzschild和Kerr SpaceTimes，该机制已被充分理解。在本文中，我们研究并明确指定了一个光子球，该光子球在动态时空中塑造了黑洞阴影，同时考虑了时空的全局结构。我们考虑了Vaidya时空的动态和永恒的黑洞案例，该案例代表了球形对称的黑洞，并积聚了无效的灰尘。首先，我们从数值上表明，在中等吸积的情况下，存在与阴影边缘相对应的动态光子球和光子轨道。其次，在特殊情况下，光子球是分析得出的。最后，我们讨论了光子球与定义为光子球概括的几个概念之间的关系。
A photon sphere is known as the geometrical structure shaping a black hole shadow. The mechanism is well understood for static or stationary black hole spacetimes such as the Schwarzschild and the Kerr spacetimes. In this paper, we investigate and explicitly specify a photon sphere that shapes a black hole shadow in a dynamical spacetime while taking the global structure of the spacetime into account. We consider dynamical and eternal black hole cases of the Vaidya spacetime, which represents a spherically symmetric black hole with accreting null dust. First, we numerically show that there are the dynamical photon sphere and photon orbits corresponding to the shadow edge in a moderate accretion case. Second, the photon spheres are derived analytically in special cases. Finally, we discuss the relation between our photon sphere and the several notions defined as a photon sphere generalization.
