Cosmological perturbations in a family of deformations of general relativity

@article{Krasnov2010CosmologicalPI,
  title={Cosmological perturbations in a family of deformations of general relativity},
  author={Kirill Krasnov and Yuri Shtanov},
  journal={Journal of Cosmology and Astroparticle Physics},
  year={2010},
  volume={2010},
  pages={006-006}
}
We study linear cosmological perturbations in a previously introduced family of deformations of general relativity characterized by the absence of new degrees of freedom. The homogeneous and isotropic background in this class of theories is unmodified and is described by the usual Friedmann equations. The theory of cosmological perturbations is modified and the relevant deformation parameter has the dimension of length. Gravitational perturbations of the scalar type can be described by a… 
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