Differentiating G-inflation from string gas cosmology using the effective field theory approach

  title={Differentiating G-inflation from string gas cosmology using the effective field theory approach},
  author={Min-Tsung He and Junyu Liu and S. Lu and Siyi Zhou and Yi-Fu Cai and Yi Wang and Robert Brandenberger},
  journal={Journal of Cosmology and Astroparticle Physics},
  pages={040 - 040}
A characteristic signature of String Gas Cosmology is primordial power spectra for scalar and tensor modes which are almost scale-invariant but with a red tilt for scalar modes but a blue tilt for tensor modes. This feature, however, can also be realized in the so-called G-inflation model, in which Horndeski operators are introduced which leads to a blue tensor tilt by softly breaking the Null Energy Condition. In this article we search for potential observational differences between these two… 
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