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arXiv · 1303.2616

Constraining Monodromy Inflation

Hiranya Peiris·Richard Easther·Raphael Flauger
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Abstract

We use cosmic microwave background (CMB) data from the 9-year WMAP release to derive constraints on monodromy inflation, which is characterized by a linear inflaton potential with a periodic modulation. We identify two possible periodic modulations that significantly improve the fit, but it is unclear whether this improvement is associated with a "signal" or with the scatter in the measured angular power spectrum. The unmodulated potential is mildly favored by standard model selection criteria. A modulated inflationary potential can generate substantial primordial non-Gaussianity, of a specific and characteristic form. For the best-fit parameters to the WMAP angular power spectrum, the corresponding non-Gaussianity might be detectable in upcoming CMB data, allowing nontrivial consistency checks on the predictions of a modulated inflationary potential.

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Hiranya Peiris, Richard Easther, Raphael Flauger. 2013-07-03. Constraining Monodromy Inflation. https://doi.org/10.1088/1475-7516%2F2013%2F09%2F018

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