论文标题
使用M87 $^*$和SGR测试通过阴影图像和弱场光子挠度测试符号重力。 $^*$结果
Testing Symmergent gravity through the shadow image and weak field photon deflection by a rotating black hole using the M87$^*$ and Sgr. A$^*$ results
论文作者
论文摘要
在本文中，我们研究了在符号重力中的旋转黑洞，并使用与Kerr黑洞的偏差来限制符号重力的参数。 Symermergent Gravity从平坦的时空循环中引起重力常数$ G $和二次曲率系数$ c _ {\ rm o} $。在所有字段质量归纳的极限下，真空能量$ v _ {\ rm o} $可以按$ g $和$ c _ {\ rm o} $全面表示。我们通过参数$ {\ hatα} $参数偏离此简并限制的偏差，使得黑洞时空为$ {\ hatα} <1 $ ds和$ {\ hat hatα}> 1 $的广告。在约束符号参数$ c _ {\ rm o} $和$ {\hatα} $时，我们利用了M87*和SGR上的EHT观测值。一个黑洞。我们首先研究了光子球和阴影大小的修饰，并在光线范围内发现了显着的偏差以及相对于Kerr溶液的阴影半径。我们还发现，时间样颗粒的测量学对符号重力效应的敏感性比无效的测量学更敏感。最后，我们分析了挠度角的弱场极限，在那里我们使用高斯 - 骨网定理考虑了源的有限距离和接收器到镜头对象的有限距离。值得注意的是，接收器（或源）与镜头对象的距离极大地影响了偏转角。此外，对于一致的解决方案，$ c _ {\ rm o} $需要负面。在我们的分析中，旋转的黑洞充当粒子加速器，并具有探测符号重力的灵敏度。
In this paper, we study rotating black holes in symmergent gravity, and use deviations from the Kerr black hole to constrain the parameters of the symmergent gravity. Symmergent gravity induces the gravitational constant $G$ and quadratic curvature coefficient $c_{\rm O}$ from the flat spacetime matter loops. In the limit in which all fields are degenerate in mass, the vacuum energy $V_{\rm O}$ can be wholly expressed in terms of $G$ and $c_{\rm O}$. We parametrize deviation from this degenerate limit by a parameter ${\hat α}$ such that the black hole spacetime is dS for ${\hat α} < 1$ and AdS for ${\hat α} > 1$. In constraining the symmergent parameters $c_{\rm O}$ and ${\hat α}$, we utilize the EHT observations on the M87* and Sgr. A* black holes. We investigate first the modifications in the photon sphere and shadow size, and find significant deviations in the photonsphere radius and the shadow radius with respect to the Kerr solution. We also find that the geodesics of time-like particles are more sensitive to symmergent gravity effects than the null geodesics. Finally, we analyze the weak field limit of the deflection angle, where we use the Gauss-Bonnet theorem for taking into account the finite distance of the source and the receiver to the lensing object. Remarkably, the distance of the receiver (or source) from the lensing object greatly influences the deflection angle. Moreover, $c_{\rm O}$ needs be negative for a consistent solution. In our analysis, the rotating black hole acts as a particle accelerator and possesses the sensitivity to probe the symmergent gravity.
