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Spatially averaged cosmology in an arbitrary coordinate system

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 Added by Julien Larena
 Publication date 2009
  fields Physics
and research's language is English
 Authors J. Larena




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This paper presents a general averaging procedure for a set of observers which are tilted with respect to the cosmological matter fluid. After giving the full set of equations describing the local dynamics, we define the averaging procedure and apply it to the scalar parts of Einsteins field equations. In addition to the standard backreaction, new terms appear that account for the effect of the peculiar velocity of the matter fluid as well as the possible effect of a shift in the coordinate system.



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