Screening vs. gevolution: in chase of a perfect cosmological simulation code
Abstract
We compare two competing relativistic approaches to the Nbody simulation of the Universe largescale 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 $\Phi$, the framedragging vector potential ${\bf B}$ and the difference between scalar modes $\chi=\Phi\Psi$. 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 $\Phi$ 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.
 Publication:

arXiv eprints
 Pub Date:
 June 2021
 arXiv:
 arXiv:2106.07638
 Bibcode:
 2021arXiv210607638E
 Keywords:

 General Relativity and Quantum Cosmology;
 Astrophysics  Cosmology and Nongalactic Astrophysics;
 High Energy Physics  Theory
 EPrint:
 16 pages, 3 figures