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arXiv · 1706.07753

Exact non-linear equations for cosmological perturbations

Jinn-Ouk Gong·Jai-chan Hwang·Hyerim Noh·David Wu·Jaiyul Yoo
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Abstract

We present a complete set of exact and fully non-linear equations describing all three types of cosmological perturbations -- scalar, vector and tensor perturbations. We derive the equations in a thoroughly gauge-ready manner, so that any spatial and temporal gauge conditions can be employed. The equations are completely general without any physical restriction except that we assume a flat homogeneous and isotropic universe as a background. We also comment briefly on the application of our formulation to the non-expanding Minkowski background.

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Jinn-Ouk Gong, Jai-chan Hwang, Hyerim Noh, David Wu, Jaiyul Yoo. 2017-06-23. Exact non-linear equations for cosmological perturbations. https://doi.org/10.1088/1475-7516%2F2017%2F10%2F027

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