Structure formation in modified gravity models

  title={Structure formation in modified gravity models},
  author={Kazuya Koyama},
  journal={Journal of Cosmology and Astroparticle Physics},
  pages={017 - 017}
  • K. Koyama
  • Published 10 January 2006
  • Physics
  • Journal of Cosmology and Astroparticle Physics
We study structure formation in phenomenological models in which the Friedmann equation receives a correction of the form Hα/rc2 − α, to realize an accelerated expansion without dark energy. In order to address structure formation in these models, we construct simple covariant gravitational equations which give the modified Friedmann equation with α = 2/n, where n is an integer. For n = 2, the underlying theory is known as a five-dimensional (5D) braneworld model (the DGP model). Thus the… 

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