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

TL;DR

This paper investigates how the peculiar motions of the lens, source, and observer affect gravitational lensing time delays, providing more realistic calculations by including these motions while neglecting gravitomagnetic effects.

Contribution

It introduces a method to account for the peculiar velocities of all three components in gravitational lensing time delay calculations, enhancing accuracy over previous models.

Findings

Peculiar motions significantly influence time delay estimates.

Neglecting these motions can lead to inaccuracies in lensing measurements.

The model improves the precision of cosmological parameter estimation.

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.