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arXiv · 1108.3813

Universal Non-Gaussian Initial Conditions for N-body Simulations

D. M. Regan·M. M. Schmittfull·E. P. S. Shellard·J. R. Fergusson
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Abstract

In this paper we present the implementation of an efficient formalism for the generation of arbitrary non-Gaussian initial conditions for use in N-body simulations. The methodology involves the use of a separable modal approach for decomposing a primordial bispectrum or trispectrum. This approach allows for the far more efficient generation of the non-Gaussian initial conditions already described in the literature, as well as the generation for the first time of non-separable bispectra and the special class of diagonal-free trispectra. The modal approach also allows for the reconstruction of the spectra from given realisations, a fact which is exploited to provide an accurate consistency check of the simulations.

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D. M. Regan, M. M. Schmittfull, E. P. S. Shellard, J. R. Fergusson. 2011-08-18. Universal Non-Gaussian Initial Conditions for N-body Simulations. https://doi.org/10.1103/physrevd.86.123524

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