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arXiv · 1210.8306

Fourth-order perturbative equations in Lagrangian perturbation theory for a cosmological dust fluid

Takayuki Tatekawa
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Abstract

We have derived fourth-order perturbative equations in Lagrangian perturbation theory for a cosmological dust fluid. These equations are derived under the supposition of Newtonian cosmology in the Friedmann-Lema\^{i}tre-Robertson-Walker Universe model. Even if we consider the longitudinal mode in the first-order perturbation, the transverse mode appears in the third-order perturbation. Furthermore, in this case, six longitudinal-mode equations and four transverse-mode equations appear in the fourth-order perturbation. The application of the fourth-order perturbation leads to a precise prediction of the large-scale structure.

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Takayuki Tatekawa. 2012-10-31. Fourth-order perturbative equations in Lagrangian perturbation theory for a cosmological dust fluid. https://doi.org/10.1093/ptep/pts053

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