Backreaction from inhomogeneous matter fields during large-scale structure formation

  title={Backreaction from inhomogeneous matter fields during large-scale structure formation},
  author={Stefan Floerchinger and Nikolaos Tetradis and Urs Achim Wiedemann},
  journal={Physical Review D},
We study how inhomogeneities of the cosmological fluid fields backreact on the homogeneous part of energy density and how they modify the Friedmann equations. In general, backreaction requires to go beyond the pressureless ideal fluid approximation, and this can lead to a reduced growth of cosmological large scale structure. Since observational evidence favours evolution close to the standard growing mode in the linear regime, we focus on two-component fluids in which the non-ideal fluid is… Expand

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