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arXiv · 1310.5186

Strong Planck constraints on braneworld and non-commutative inflation

Gianluca Calcagni·Sachiko Kuroyanagi·Junko Ohashi·Shinji Tsujikawa
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Abstract

We place observational likelihood constraints on braneworld and non-commutative inflation for a number of inflaton potentials, using Planck, WMAP polarization and BAO data. Both braneworld and non-commutative scenarios of the kind considered here are limited by the most recent data even more severely than standard general-relativity models. At more than 95 % confidence level, the monomial potential $V(ϕ) \propto ϕ^p$ is ruled out for $p \geq 2$ in the Randall--Sundrum (RS) braneworld cosmology and, for $p>0$, also in the high-curvature limit of the Gauss--Bonnet (GB) braneworld and in the infrared limit of non-commutative inflation, due to a large scalar spectral index. Some parameter values for natural inflation, small-varying inflaton models and Starobinsky inflation are allowed in all scenarios, although some tuning is required for natural inflation in a non-commutative spacetime.

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Gianluca Calcagni, Sachiko Kuroyanagi, Junko Ohashi, Shinji Tsujikawa. 2014-03-29. Strong Planck constraints on braneworld and non-commutative inflation. https://doi.org/10.1088/1475-7516%2F2014%2F03%2F052

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