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arXiv · 1904.07841

General Relativistic Cosmological N-body Simulations I: time integration

David Daverio·Yves Dirian·Ermis Mitsou
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Abstract

This is the first in a series of papers devoted to fully general-relativistic $N$-body simulations applied to late-time cosmology. The purpose of this paper is to present the combination of a numerical relativity scheme, discretization method and time-integration algorithm that provides satisfyingly stable evolution. More precisely, we show that it is able to pass a robustness test and to follow scalar linear modes around an expanding homogeneous and isotropic space-time. Most importantly, it is able to evolve typical cosmological initial conditions on comoving scales down to tenths of megaparsecs with controlled constraint and energy-momentum conservation violations all the way down to the regime of strong inhomogeneity.

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David Daverio, Yves Dirian, Ermis Mitsou. 2019-04-16. General Relativistic Cosmological N-body Simulations I: time integration. https://doi.org/10.1088/1475-7516%2F2019%2F10%2F065

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