Including relativistic and primordial non-Gaussianity contributions in cosmological simulations by modifying the initial conditions

Abstract We present a method to implement relativistic corrections the evolution of dark matter structures in Newtonian simulations ΛCDM universe via initial conditions. take nonlinear correspondence between Lagrangian (Newtonian) inhomogeneities and synchronous-comoving (relativistic) density description, use it promote constraint as condition for numerical structure formation. In this case, incorporation Primordial non-Gaussianity (PNG) contributions conditions is straightforward. relativistic, f NL g L-PICOLA code, compute power spectrum bispectrum evolved field. focus specifically on case largest values allowed at 1- σ by Planck observations ( = −4.2 −7000). As checkup, we show consistency with one-loop perturbative prescription fully simulation GRAMSES ) adequate scales. Our results confirm that both PNG features are most prominent very large scales squeezed triangulations. discuss future prospects probe these two distribution.