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Unimodular Gravity and Averaging

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DOI: 10.4236/jmp.2012.33036    4,071 Downloads   6,848 Views   Citations

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.

Conflicts of Interest

The authors declare no conflicts of interest.

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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