Does the growth of structure affect our dynamical models of the universe? The averaging, backreaction and fitting problems in cosmology

  title={Does the growth of structure affect our dynamical models of the universe? The averaging, backreaction and fitting problems in cosmology},
  author={Chris A. Clarkson and George F R Ellis and Julien Larena and Obinna Umeh},
  journal={Reports on Progress in Physics},
Structure occurs over a vast range of scales in the Universe. Our large-scale cosmological models are coarse-grained representations of what exists, which have much less structure than there really is. An important problem for cosmology is determining the influence the small-scale structure in the Universe has on its large-scale dynamics and observations. Is there a significant, general relativistic, backreaction effect from averaging over structure? One issue is whether the process of… Expand

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