N-body simulation of the cosmic screening effect

We consider the large-scale structure formation within the cosmic screening approach. The main feature of this approach is that a careful analysis of the perturbed Einstein equations leads to the conclusion that there is an exponential cutoff of the gravitational interaction on large (of the order of 2–3 Gpc) cosmological scales. This is a purely relativistic effect associated with the non-linearity of Einstein's equations. Consequently, the gravitational potential is described by an equation of Helmholtz-type and not of Poisson-type and it has the form of the Yukawa potential, and not the Newton potential familiar to us from school days. To confirm this effect numerically, we perform the N-body simulation in a box with a comoving size of 5.632 Gps/h employing the relativistic code “gevolution” modified to our approach. We calculate the power spectra of the mass density contrast and find that these spectra cease to depend on time for scales beyond the cosmic screening length. This is a clear manifestation of the cosmic screening effect.