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arXiv · 1803.08766

Perturbative treatment of the luminosity distance

Dimitar Ivanov·Stefano Liberati·Matteo Viel·Matt Visser
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Abstract

We derive a generalized luminosity distance versus redshift relation for a linearly perturbed FLRW (Friedmann-Lemaitre-Robertson-Walker) metric with two scalar mode excitations. We use two equivalent approaches, based on the Jacobi map and the van Vleck determinant respectively. We apply the resultant formula to two simple models - an exact FLRW universe and an approximate FLRW universe perturbed by a single scalar mode sinusoidally varying with time. For both models we derive a cosmographic expansion for d_L in terms of z. We comment on the interpretation of our results and their possible application to more realistic cosmological models.

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Dimitar Ivanov, Stefano Liberati, Matteo Viel, Matt Visser. 2018-09-17. Perturbative treatment of the luminosity distance. https://doi.org/10.1103/physrevd.98.063505

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