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arXiv · 1409.3921

The time delay in strong gravitational lensing with Gauss-Bonnet correction

Jingyun Man·Hongbo Cheng
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Abstract

The time delay between two relativistic images in the strong gravitational lensing governed by Gauss-Bonnet gravity is studied. We derive and calculate the expression of time delay due to the Gauss-Bonnet coupling. It is shown that the time delay for two images with larger space each other is longer. We also find that the ratio of Gauss-Bonnet coefficient and the mass of gravitational source changes in the region like $\fracα{M}\in[0,2)$. The time delay is divergent with $\fracα{M}\longrightarrow 2$.

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Jingyun Man, Hongbo Cheng. 2014-09-13. The time delay in strong gravitational lensing with Gauss-Bonnet correction. https://doi.org/10.1088/1475-7516%2F2014%2F11%2F025

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