Effects of Nonlinear Inhomogeneity on the Cosmic Expansion with Numerical Relativity.

  title={Effects of Nonlinear Inhomogeneity on the Cosmic Expansion with Numerical Relativity.},
  author={Eloisa Bentivegna and Marco Bruni},
  journal={Physical review letters},
  volume={116 25},
We construct a three-dimensional, fully relativistic numerical model of a universe filled with an inhomogeneous pressureless fluid, starting from initial data that represent a perturbation of the Einstein-de Sitter model. We then measure the departure of the average expansion rate with respect to this homogeneous and isotropic reference model, comparing local quantities to the predictions of linear perturbation theory. We find that collapsing perturbations reach the turnaround point much… Expand

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