We study the effect of primordial non–Gaussianity on the development of large-scale cosmic structure using high-resolution N -body simulations .
In particular , we focus on the topological properties of the “ cosmic web ” , quantitatively characterized by the Minkowski Functionals , for models with quadratic non-linearities with different values of the usual non–Gaussianity parameter f _ { NL } .
In the weakly non-linear regime ( the amplitude of mass density fluctuations \sigma _ { 0 } < 0.1 ) , we find that analytic formulae derived from perturbation theory agree with the numerical results within a few percent of the amplitude of each MF when |f _ { NL } | < 1000 .
In the non-linear regime , the detailed behavior of the MFs as functions of threshold density deviates more strongly from the analytical curves , while the overall amplitude of the primordial non–Gaussian effect remains comparable to the perturbative prediction .
When smaller-scale information is included , the influence of primordial non–Gaussianity becomes increasingly significant statistically due to decreasing sample variance .
We find that the effect of the primordial non-Gaussianity with |f _ { NL } | = 50 is comparable to the sample variance of mass density fields with a volume of 0.125 ( h ^ { -1 } { Gpc } ) ^ { 3 } when they are smoothed by Gaussian filter at a scale of 5 h ^ { -1 } Mpc .
The detectability of this effect in actual galaxy surveys will strongly depend upon residual uncertainties in cosmological parameters and galaxy biasing .