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arXiv · 0908.4281

Averaging in cosmological models using scalars

A. A. Coley
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Abstract

The averaging problem in cosmology is of considerable importance for the correct interpretation of cosmological data. A rigorous mathematical definition of averaging in a cosmological model is necessary. In general, a spacetime is completely characterized by its scalar curvature invariants, and this suggests a particular spacetime averaging scheme based entirely on scalars. We clearly identify the problems of averaging in a cosmological model. We then present a precise definition of a cosmological model, and based upon this definition, we propose an averaging scheme in terms of scalar curvature invariants. This scheme is illustrated in a simple static spherically symmetric perfect fluid cosmological spacetime, where the averaging scales are clearly identified.

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A. A. Coley. 2009-08-28. Averaging in cosmological models using scalars. https://doi.org/10.1088/0264-9381%2F27%2F24%2F245017

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