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arXiv · 2011.04440

Gravitational lenses in arbitrary space-times

Pierre Fleury·Julien Larena·Jean-Philippe Uzan
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Abstract

The precision reached by current and forthcoming strong-lensing observations requires to accurately model various perturbations to the main deflector. Hitherto, theoretical models have been developed to account for either cosmological line-of-sight perturbations, or isolated secondary lenses via the multi-plane lensing framework. This article proposes a general formalism to describe multiple lenses within an arbitrary space-time background. The lens equation, and the expressions of the amplification and time delays, are rigorously derived in that framework. Our results may be applied to a wide range of set-ups, from strong lensing in anisotropic cosmologies, to line-of-sight perturbations beyond the tidal regime.

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Pierre Fleury, Julien Larena, Jean-Philippe Uzan. 2020-11-09. Gravitational lenses in arbitrary space-times. https://doi.org/10.1088/1361-6382%2Fabea2d

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