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arXiv · 2106.07638

Screening vs. gevolution: in chase of a perfect cosmological simulation code

Maxim Eingorn·A. Emrah Yukselci·Alexander Zhuk
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Abstract

We compare two competing relativistic approaches to the N-body simulation of the Universe large-scale structure. To this end, employing the corresponding alternative computer codes ("gevolution" and "screening"), we conduct a series of cosmological simulations in boxes of different sizes and calculate the power spectra of the scalar perturbation $Φ$, the frame-dragging vector potential ${\bf B}$ and the difference between scalar modes $χ=Φ-Ψ$. We demonstrate that the corresponding power spectra are in very good agreement between the compared schemes. For example, the relative difference of the power spectra for $Φ$ is 0.04% maximum. Since the perturbed Einstein equations have much simpler form in the screening approach, the simulation with this code consumes less computational time, saving almost 40% of CPU hours.

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Maxim Eingorn, A. Emrah Yukselci, Alexander Zhuk. 2021-06-14. Screening vs. gevolution: in chase of a perfect cosmological simulation code. https://doi.org/10.1016/j.physletb.2022.136911

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