Screening vs. gevolution: in chase of a perfect cosmological simulation
  code
  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 $\Phi$, the frame-dragging 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.
