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 JMP  Vol.3 No.3 , March 2012
Unimodular Gravity and Averaging
Alan Coley, Johan Brannlund, Joey Latta
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Abstract: The question of the averaging of inhomogeneous spacetimes in cosmology is important for the correct interpretation of cosmological data. In this paper a conceptually simpler approach to averaging in cosmology is suggested, based on the averaging of scalars within unimodular gravity. As an illustration, the example of an exact spherically symmetric dust model is considered, and it is shown that within this approach averaging introduces correlations (corrections) to the effective dynamical evolution equation in the form of a spatial curvature term.
Keywords: Inhomogeneous Cosmology; Averaging; Unimodular Gravity
Cite this paper: A. Coley, J. Brannlund and J. Latta, "Unimodular Gravity and Averaging," Journal of Modern Physics, Vol. 3 No. 3, 2012, pp. 266-270. doi: 10.4236/jmp.2012.33036.
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