# Exact solution to the averaging problem in cosmology.

@article{Wiltshire2007ExactST, title={Exact solution to the averaging problem in cosmology.}, author={David L. Wiltshire}, journal={Physical review letters}, year={2007}, volume={99 25}, pages={ 251101 } }

The exact solution of a two-scale Buchert average of the Einstein equations is derived for an inhomogeneous universe that represents a close approximation to the observed universe. The two scales represent voids, and the bubble walls surrounding them within which clusters of galaxies are located. As described elsewhere [New J. Phys. 9, 377 (2007)10.1088/1367-2630/9/10/377], apparent cosmic acceleration can be recognized as a consequence of quasilocal gravitational energy gradients between…

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