Cosmology Without Averaging - General Relativity and Quantum CosmologyReport as inadecuate

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Abstract: We construct cosmological models consisting of large numbers of identical,regularly spaced masses. These models do not rely on any averaging procedures,or on the existence of a global Friedmann-Robertson-Walker FRW background.They are solutions of Einstein-s equations up to higher order corrections in aperturbative expansion, and have large-scale dynamics that are well modelled bythe Friedmann equation. We find that the existence of arbitrarily large densitycontrasts does not change either the magnitude or scale of the backgroundexpansion, at least when masses are regularly arranged, and up to theprescribed level of accuracy. We also find that while the local space-timegeometry inside each cell can be described as linearly perturbed FRW, one couldargue that a more natural description is that of perturbed Minkowski space inwhich case the scalar perturbations are simply Newtonian potentials. We expectthese models to be of use for understanding and testing ideas about averagingin cosmology, as well as clarifying the relationship between globalcosmological dynamics and the static space-times associated with isolatedmasses.

Author: Timothy Clifton



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