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arXiv · 1511.02220

Second-order cosmological perturbation theory and initial conditions for $N$-body simulations

Adam J. Christopherson·Juan Carlos Hidalgo·Cornelius Rampf·Karim A. Malik
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Abstract

We use gauge-invariant cosmological perturbation theory to calculate the displacement field that sets the initial conditions for $N$-body simulations. Using first and second-order fully relativistic perturbation theory in the synchronous-comoving gauge, allows us to go beyond the Newtonian predictions and to calculate relativistic corrections to it. We use an Einstein--de Sitter model, including both growing and decaying modes in our solutions. The impact of our results should be assessed through the implementation of the featured displacement in cosmological $N$-body simulations.

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Adam J. Christopherson, Juan Carlos Hidalgo, Cornelius Rampf, Karim A. Malik. 2015-12-23. Second-order cosmological perturbation theory and initial conditions for $N$-body simulations. https://doi.org/10.1103/physrevd.93.043539

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