General relativistic weak-field limit and Newtonian N-body simulations

  title={General relativistic weak-field limit and Newtonian N-body simulations},
  author={Christian Fidler and Thomas Tram and Cornelius Rampf and Robert G. Crittenden and Kazuya Koyama and David I F Wands},
  journal={arXiv: Cosmology and Nongalactic Astrophysics},
We show how standard Newtonian N-body simulations can be interpreted in terms of the weak-field limit of general relativity by employing the recently developed Newtonian motion gauge. Our framework allows the inclusion of radiation perturbations and the non-linear evolution of matter. We show how to construct the weak-field metric by combining Newtonian simulations with results from Einstein-Boltzmann codes. We discuss observational effects on weak lensing and ray tracing, identifying important… Expand

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