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arXiv · 2003.08014

Numerical solutions to Einstein's equations in a shearing-dust Universe: a code comparison

Julian Adamek·Cristian Barrera-Hinojosa·Marco Bruni·Baojiu Li·Hayley J. Macpherson·James B. Mertens
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Abstract

A number of codes for general-relativistic simulations of cosmological structure formation have been developed in recent years. Here we demonstrate that a sample of these codes produce consistent results beyond the Newtonian regime. We simulate solutions to Einstein's equations dominated by gravitomagnetism -- a vector-type gravitational field that doesn't exist in Newtonian gravity and produces frame-dragging, the leading-order post-Newtonian effect. We calculate the coordinate-invariant effect on intersecting null geodesics by performing ray tracing in each independent code. With this observable quantity, we assess and compare each code's ability to compute relativistic effects.

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Julian Adamek, Cristian Barrera-Hinojosa, Marco Bruni, Baojiu Li, Hayley J. Macpherson, James B. Mertens. 2020-05-19. Numerical solutions to Einstein's equations in a shearing-dust Universe: a code comparison. https://doi.org/10.1088/1361-6382%2Fab939b

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