Exact solution to the averaging problem in cosmology.

  title={Exact solution to the averaging problem in cosmology.},
  author={David L. Wiltshire},
  journal={Physical review letters},
  volume={99 25},
  • D. Wiltshire
  • Published 2007
  • Physics, Medicine
  • Physical review letters
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… Expand

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