# Lensing in the geodesic light-cone coordinates and its (exact) illustration to an off-center observer in Lemaȋtre-Tolman-Bondi models

@article{Fanizza2015LensingIT,
title={Lensing in the geodesic light-cone coordinates and its (exact) illustration to an off-center observer in Lemaȋtre-Tolman-Bondi models},
author={Giuseppe Fanizza and Fabien Nugier},
journal={Journal of Cosmology and Astroparticle Physics},
year={2015},
volume={2015},
pages={002 - 002}
}
• Published 7 August 2014
• Physics
• Journal of Cosmology and Astroparticle Physics
We present in this paper a new application of the geodesic light-cone (GLC) gauge for weak lensing calculations. Using interesting properties of this gauge, we derive an exact expression of the amplification matrix—involving convergence, magnification and shear—and of the deformation matrix—involving the optical scalars. These expressions are simple and non-perturbative as long as no caustics are created on the past light-cone and are, by construction, free from the thin lens approximation. We…
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