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arXiv · 2301.08622

The Effect of the Peculiar Motions of the Lens, Source and the Observer on the Gravitational Lensing Time Delay

Gihan Weerasekara·Thulsi Wickramasinghe·Chandana Jayaratne
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Abstract

An intervening galaxy acts as a gravitational lens and produces multiple images of a single source such as a remote galaxy. Galaxies have peculiar speeds in addition to the bulk motion arising due to the expansion of the universe. There is a difference in light arrival times between lensed images. We calculate more realistic time delays between lensed images when galaxy peculiar motions, that is the motion of the Lens, the Source and the Observer are taken into consideration neglecting the gravitomagnetic effects.

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Gihan Weerasekara, Thulsi Wickramasinghe, Chandana Jayaratne. 2023-01-20. The Effect of the Peculiar Motions of the Lens, Source and the Observer on the Gravitational Lensing Time Delay. https://arxiv.org/abs/2301.08622

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