Swiss-cheese models and the Dyer-Roeder approximation

  title={Swiss-cheese models and the Dyer-Roeder approximation},
  author={Pierre Fleury},
  journal={Journal of Cosmology and Astroparticle Physics},
  pages={054 - 054}
  • P. Fleury
  • Published 13 February 2014
  • Physics
  • Journal of Cosmology and Astroparticle Physics
In view of interpreting the cosmological observations precisely, especially when they involve narrow light beams, it is crucial to understand how light propagates in our statistically homogeneous, clumpy, Universe. Among the various approaches to tackle this issue, Swiss-cheese models propose an inhomogeneous spacetime geometry which is an exact solution of Einstein's equation, while the Dyer-Roeder approximation deals with inhomogeneity in an effective way. In this article, we demonstrate that… 

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