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

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 نشر من قبل Carlos Hidalgo
 تاريخ النشر 2015
  مجال البحث فيزياء
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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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