论文标题
Rastall Gravity中轴向对称黑洞的光学特性
Optical Properties of an Axially Symmetric Black Hole in the Rastall Gravity
论文作者
论文摘要
这项工作致力于研究重力理论中带电的旋转 - nut-kiselev（CRNK）黑洞的光学性质。通过研究rastall重力中CRNK黑洞时空中光子的运动，我们表明，由于重力透镜引起的光子的挠度角度主要受螺母电荷，典当状态和典型强度的状态方程的参数。我们观察到，其余的时空参数的效果在偏转角上可以忽略不计。我们介绍了Rastall Gravity中Crnk Black Hole铸造的阴影的形状，以实现时空参数的各种值。我们证明，旋转参数$ a $的黑洞很少会改变黑洞阴影的位置和大小。在更改时空参数的值时，可以显着改变黑洞的阴影的形状和大小。我们观察到，与Kerr Black Hole的情况相比，对于Rastall Gravity中的CRNK黑洞，黑洞阴影的半径和光子的挠度角度更大。最后，我们展示了时空参数如何更改可观察到的$ r_s $和$δ_s$，这是阴影的平均半径和分别测量阴影形状偏离完美圆圈的变形参数，分别是半径$ r_s $。我们的结果表明，在大多数情况下，对于$ r_s $的较大值，我们获得了较小的参数$δ_s$的值。
This work is devoted to the study of the optical properties of the charged-rotating-NUT-Kiselev (CRNK) black hole in the Rastall theory of gravity. By investigating the motion of photons in the CRNK black hole spacetime in the Rastall gravity we show that the deflection angle of photons due to the gravitational lensing is mostly influenced by the NUT charge, parameter of the equation of state for the quintessence and the quintessential intensity. We observe that the effects of the rest of the spacetime parameters are negligible on the deflection angle. We present the shape of the shadow cast by the CRNK black hole in the Rastall gravity for various values of the spacetime parameters. We demonstrate that spin parameter $a$ of the black hole changes the position and size of the shadow of the black hole very little. While changing the values of the rest of the spacetime parameters can alter the shape and the size of the observed shadow of the black hole significantly. We observe that the radius of the black hole shadow and the deflection angle of a photon are bigger for the CRNK black hole in the Rastall gravity, as compared with the case of the Kerr black hole. Lastly, we show how the spacetime parameters can change the observables $R_s$ and $δ_s$, being the average radius of the shadow and the distortion parameter that measures the deviation of the shape of the shadow from a perfect circle with radius $R_s$, respectively. Our results show that in most scenarios, for bigger values of $R_s$ we get smaller values of the parameter $δ_s$.
