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arXiv · 1104.1167

Light-cone averaging in cosmology: formalism and applications

M. Gasperini·G. Marozzi·F. Nugier·G. Veneziano
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Abstract

We present a general gauge invariant formalism for defining cosmological averages that are relevant for observations based on light-like signals. Such averages involve either null hypersurfaces corresponding to a family of past light-cones or compact surfaces given by their intersection with timelike hypersurfaces. Generalized Buchert-Ehlers commutation rules for derivatives of these light-cone averages are given. After introducing some adapted "geodesic light-cone" coordinates, we give explicit expressions for averaging the redshift to luminosity-distance relation and the so-called "redshift drift" in a generic inhomogeneous Universe.

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M. Gasperini, G. Marozzi, F. Nugier, G. Veneziano. 2011-04-06. Light-cone averaging in cosmology: formalism and applications. https://doi.org/10.1088/1475-7516/2011/07/008

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