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Growth of correlations in gravitational N-body simulations

Thierry Baertschiger·Francesco Sylos Labini
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Abstract

In the gravitational evolution of a cold infinite particle distribution, two-body interactions can be predominant at early times: we show that, by treating the simple case of a Poisson particle distribution in a static universe as an ensemble of isolated two-body systems, one may capture the origin of the first non-linear correlated structures. The developed power-law like behavior of the two-point correlation function is then simply related to the functional form of the time evolved nearest-neighbor probability distribution, whose time dependence can be computed by using Liouville theorem for the gravitational two-body problem. We then show that a similar dynamical evolution is also found in a large-scale ordered distribution, which has striking similarities to the case of a cosmological CDM simulation which we also consider.

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BibTeXRIS

Thierry Baertschiger, Francesco Sylos Labini. 2004-01-13. Growth of correlations in gravitational N-body simulations. https://doi.org/10.1103/physrevd.69.123001

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