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arXiv · 1407.7979

Large-Scale Structure Observables in General Relativity

Donghui Jeong·Fabian Schmidt
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Abstract

We review recent studies that rigorously define several key observables of the large-scale structure of the Universe in a general relativistic context. Specifically, we consider i) redshift perturbation of cosmic clock events; ii) distortion of cosmic rulers, including weak lensing shear and magnification; iii) observed number density of tracers of the large-scale structure. We provide covariant and gauge-invariant expressions of these observables. Our expressions are given for a linearly perturbed flat Friedmann-Robertson-Walker metric including scalar, vector, and tensor metric perturbations. While we restrict ourselves to linear order in perturbation theory, the approach can be straightforwardly generalized to higher order.

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Donghui Jeong, Fabian Schmidt. 2014-07-30. Large-Scale Structure Observables in General Relativity. https://doi.org/10.1088/0264-9381/32/4/044001

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