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arXiv · 0801.4208

Lagrangian reconstruction of cosmic velocity fields

G. Lavaux
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Abstract

We discuss a Lagrangian reconstruction method of the velocity field from galaxy redshift catalog that takes its root in the Euler equation. This results in a ``functional'' of the velocity field which must be minimized. This is helped by an algorithm solving the minimization of cost-flow problems. The results obtained by applying this method to cosmological problems are shown and boundary effects happening in real observational cases are then discussed. Finally, a statistical model of the errors made by the reconstruction method is proposed.

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G. Lavaux. 2008-01-28. Lagrangian reconstruction of cosmic velocity fields. https://doi.org/10.1016/j.physd.2008.02.016

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