论文标题
$ 4D $ EINSTEIN-GAUSS-BONNET重力的黑洞重力镜头
Gravitational lensing by black holes in the $4D$ Einstein-Gauss-Bonnet gravity
论文作者
论文摘要
最近，通过将GB耦合参数重新缩放为$α/（D-4）$的非客气$ 4D $ 4D $ 4D $ EINSTEIN-GAUSS-BONNET（EGB）的重力理论，在\ cite {glavan：glavan：2019inb}中得出，绕过Lovelock lovelock lovelock的Theorem and Expersskyskyskysboilagradsy。该理论承认一个静态的球形对称黑洞，与$ 5D $ EGB或一般相对论对应物不同，该黑洞可能具有cauchy和事件范围。我们将先前的工作推广到Schwarzschild Black Hole上的重力镜头，以$ 4D $ EGB黑洞的强和弱挠度极限，以计算挠度系数$ \ bar {a} $和$ \ bar {b} $，而以前的增长和以前的增加和以后会增加$ al $α$α$。我们还发现，偏转角$α_d$，角度位置$θ_ {\ infty} $和$ u_ {m} $减少，但是Angular Spairation $ S $随$α$增加。在SGRA*和M87*黑洞的背景下，讨论了GB耦合参数$α$ $α$对位置和源相对学图像的放大的影响。 A brief description of the weak gravitational lensing using the Gauss-Bonnet theorem is presented.
Recently, a non-trivial $4D$ Einstein-Gauss-Bonnet (EGB) theory of gravity, by rescaling the GB coupling parameter as $α/(D-4)$, was formulated in \cite{Glavan:2019inb}, which bypasses Lovelock's theorem and avoids Ostrogradsky instability. The theory admits a static spherically symmetric black hole, unlike $5D$ EGB or general relativity counterpart, which can have both Cauchy and event horizons. We generalize previous work, on gravitational lensing by a Schwarzschild black hole, in the strong and weak deflection limits to the $4D$ EGB black holes to calculate the deflection coefficients $\bar{a}$ and $\bar{b}$, while former increases and later decrease with increasing $α$. We also find that the deflection angle $α_D$, angular position $θ_{\infty}$ and $u_{m}$ decreases, but angular separation $s$ increases with $α$. The effect of the GB coupling parameter $α$ on positions and magnification of the source relativistic images is discussed in the context of SgrA* and M87* black holes. A brief description of the weak gravitational lensing using the Gauss-Bonnet theorem is presented.
