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arXiv · 1703.08552

Light-Cone Observables and Gauge-Invariance in the Geodesic Light-Cone Formalism

Fulvio Scaccabarozzi·Jaiyul Yoo
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Abstract

The remarkable properties of the geodesic light-cone (GLC) coordinates allow analytic expressions for the light-cone observables, providing a new non-perturbative way for calculating the effects of inhomogeneities in our Universe. However, the gauge-invariance of these expressions in the GLC formalism has not been shown explicitly. Here we provide this missing part of the GLC formalism by proving the gauge-invariance of the GLC expressions for the light-cone observables, such as the observed redshift, the luminosity distance, and the physical area and volume of the observed sources. Our study provides a new insight on the properties of the GLC coordinates and it complements the previous work by the GLC collaboration, leading to a comprehensive description of light propagation in the GLC representation.

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Fulvio Scaccabarozzi, Jaiyul Yoo. 2017-03-24. Light-Cone Observables and Gauge-Invariance in the Geodesic Light-Cone Formalism. https://doi.org/10.1088/1475-7516%2F2017%2F06%2F007

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