A ΛCDM bounce scenario

  title={A $\Lambda$CDM bounce scenario},
  author={Yi-Fu Cai and Edward Wilson-Ewing},
  journal={Journal of Cosmology and Astroparticle Physics},
  pages={006 - 006}
We study a contracting universe composed of cold dark matter and radiation, and with a positive cosmological constant. As is well known from standard cosmological perturbation theory, under the assumption of initial quantum vacuum fluctuations the Fourier modes of the comoving curvature perturbation that exit the (sound) Hubble radius in such a contracting universe at a time of matter-domination will be nearly scale-invariant. Furthermore, the modes that exit the (sound) Hubble radius when the… 
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