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arXiv · 1609.07633

Exact gravitational lensing in conformal gravity and Schwarzschild-de Sitter spacetime

Yen-Kheng Lim·Qing-hai Wang
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Abstract

An exact solution is obtained for the gravitational bending of light in static, spherically symmetric metrics which includes the Schwarzschild-de Sitter spacetime and also the Mannheim-Kazanas metric of conformal Weyl gravity. From the exact solution, we obtain a small bending-angle-approximation for a lens system where the source, lens and observer are co-aligned. This expansion improves previous calculations where we systematically avoid parameter ranges that correspond to non-existent null trajectories. The linear coefficient $\gamma$ characteristic to conformal gravity is shown to contribute enhanced deflection compared to the angle predicted by General Relativity for small $\gamma$.

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Yen-Kheng Lim, Qing-hai Wang. 2016-09-24. Exact gravitational lensing in conformal gravity and Schwarzschild-de Sitter spacetime. https://doi.org/10.1103/physrevd.95.024004

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