arXivDaily arXiv每日学术速递 周一至周五更新
arXiv 2006.03376gr-qchep-thmath-phmath.MP
收藏

双黑洞度规中的光线偏折

Light bending in a two black hole metric

M. Alrais Alawadi, D. Batic, M. Nowakowski

AI总结:

本文研究C度规中光的传播,发现零测地线仅在特定轨道锥体上有圆轨道,证明其Jacobi不稳定,并推导了压缩因子及弱强引力透镜偏折角的解析公式。

摘要:

我们讨论了C度规中光的传播。我们发现,零测地线仅对某一族轨道锥体允许圆轨道。我们推导了轨道半径及固定锥体的相应张角的显式解析公式。此外,我们证明了这些基于有效势中鞍点的轨道是Jacobi不稳定的。这完成了先前文献中的稳定性分析,并使我们能够探究双黑洞度规中的光线偏折。更精确地说,通过在新曼-彭罗斯形式中构造合适的标架,我们证明了该几何中的光传播是无剪切、无旋转的,并且经过C黑洞的光束会经历聚焦过程。我们推导并讨论了压缩因子$θ$的精确解析公式。此外,我们研究了当观察者和光线均属于上述不变锥体族时的弱场和强场引力透镜效应。特别地,我们获得了在弱场和强场引力透镜区域中计算偏折角的公式。

英文摘要:

We discuss the propagation of light in the C-metric. We discover that null geodesics admit circular orbits only for a certain family of orbital cones. Explicit analytic formulae are derived for the orbital radius and the corresponding opening angle fixing the cone. Furthermore, we prove that these orbits based on a saddle point in the effective potential are Jacobi unstable. This completes the stability analysis done in previous literature and allows us to probe into the light bending in a two black hole metric. More precisely, by constructing a suitable tetrad in the Newmann-Penrose formalism, we show that light propagation in this geometry is shear-free, irrotational, and a light beam passing by a C-black hole undergoes a focussing process. An exact analytic formula for the compression factor $θ$ is derived and discussed. Furthermore, we study the weak and strong gravitational lensing when both the observer and the light ray belong to the aforementioned family of invariant cones. In particular, we obtain formulae allowing to calculate the deflection angle in the weak and strong gravitational lensing regimes.

机构、总结、中文摘要均由AI分析而来,可能存在错误,请以论文正文为准。

↑