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arXiv · 1209.4326

The second-order luminosity-redshift relation in a generic inhomogeneous cosmology

Ido Ben-Dayan·Giovanni Marozzi·Fabien Nugier·Gabriele Veneziano
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Abstract

After recalling a general non-perturbative expression for the luminosity-redshift relation holding in a recently proposed "geodesic light-cone" gauge, we show how it can be transformed to phenomenologically more convenient gauges in which cosmological perturbation theory is better understood. We present, in particular, the complete result on the luminosity-redshift relation in the Poisson gauge up to second order for a fairly generic perturbed cosmology, assuming that appreciable vector and tensor perturbations are only generated at second order. This relation provides a basic ingredient for the computation of the effects of stochastic inhomogeneities on precision dark-energy cosmology whose results we have anticipated in a recent letter. More generally, it can be used in connection with any physical information carried by light-like signals traveling along our past light-cone.

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Ido Ben-Dayan, Giovanni Marozzi, Fabien Nugier, Gabriele Veneziano. 2012-11-02. The second-order luminosity-redshift relation in a generic inhomogeneous cosmology. https://doi.org/10.1088/1475-7516%2F2012%2F11%2F045

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