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arXiv · 1208.3927

3+1 geodesic equation and images in numerical spacetimes

Frederic H. Vincent·Eric Gourgoulhon·Jérôme Novak
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Abstract

The equations governing null and timelike geodesics are derived within the 3+1 formalism of general relativity. In addition to the particle's position, they encompass an evolution equation for the particle's energy leading to a 3+1 expression of the redshift factor for photons. An important application is the computation of images and spectra in spacetimes arising from numerical relativity, via the ray-tracing technique. This is illustrated here by images of numerically computed stationary neutron stars and dynamical neutron stars collapsing to a black hole.

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Frederic H. Vincent, Eric Gourgoulhon, Jérôme Novak. 2012-10-24. 3+1 geodesic equation and images in numerical spacetimes. https://doi.org/10.1088/0264-9381%2F29%2F24%2F245005

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