Friedmann cosmology and almost isotropy

@article{Sormani2003FriedmannCA,
  title={Friedmann cosmology and almost isotropy},
  author={Christina Sormani},
  journal={Geometric \& Functional Analysis GAFA},
  year={2003},
  volume={14},
  pages={853-912}
}
  • C. Sormani
  • Published 19 February 2003
  • Mathematics
  • Geometric & Functional Analysis GAFA
AbstractIn the Friedmann model of the universe, cosmologists assume that spacelike slices of the universe are Riemannian manifolds of constant sectional curvature. This assumption is justified via Schur’s theorem by stating that the spacelike universe is locally isotropic. Here we define a Riemannian manifold as almost locally isotropic in a sense which allows both weak gravitational lensing in all directions and strong gravitational lensing in localized angular regions at most points. We then… 
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