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Eternal inflation disfavored by Planck and BICEP2?

  1. Apr 18, 2014 #1


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    This paper; http://arxiv.org/abs/1404.4614, Negative running prevents eternal inflation, claims Planck and BICEP2 data favors negative running of the spectral index of curvature perturbations from inflation at the 2 sigma level. It further asserts this is sufficient to preclude eternal inflation.
  2. jcsd
  3. Apr 18, 2014 #2
    Interesting article, will be interesting to see how it pans out.
  4. Apr 18, 2014 #3


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    Yes, the negative running that seems to be required on superhorizon scales in order to reconcile BICEP2 and Planck implies a maximum amplitude for curvature perturbations on these scales. Meanwhile, eternal inflation requires large density fluctuations that dominate over the classical evolution of the inflaton. These two ideas seem in conflict.
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