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Future weak lensing constraints in a dark coupled universe

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 نشر من قبل Alessandro Melchiorri dr.
 تاريخ النشر 2011
  مجال البحث فيزياء
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Coupled cosmologies can predict values for the cosmological parameters at low redshifts which may differ substantially from the parameters values within non-interacting cosmologies. Therefore, low redshift probes, as the growth of structure and the dark matter distribution via galaxy and weak lensing surveys constitute a unique tool to constrain interacting dark sector models. We focus here on weak lensing forecasts from future Euclid and LSST-like surveys combined with the ongoing Planck cosmic microwave background experiment. We find that these future data could constrain the dimensionless coupling to be smaller than a few $times 10^{-2}$. The coupling parameter $xi$ is strongly degenerate with the cold dark matter energy density $Omega_{c}h^2$ and the Hubble constant $H_0$.These degeneracies may cause important biases in the cosmological parameter values if in the universe there exists an interaction among the dark matter and dark energy sectors.



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