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DOE OSTI · 1852391

Dynamical inflection point inflation

Bai, Yang·Stolarski, Daniel
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Abstract

Abstract We provide a mechanism to obtain multiple inflection points for the inflaton potential based on the Coleman-Weinberg potential. The key ingredient is the existence of zeros of the inflaton quartic coupling beta function, which can be simply realized by a sign change of a gauge coupling beta function at a massive threshold scale in gauge-Yukawa models. A universal inflaton potential emerges for a wide range of models and can accommodate the observational data in the small-field inflation scenario. While the ratio of tensor over scalar amplitudes is predicted to be small, the running of the scalar spectral index, α s , has branches with both positive and negative values. The positive branch with α s ≳ 0.002 will be tested by the coming cosmic microwave background observations.

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Bai, Yang, Stolarski, Daniel. 2021-03-01. Dynamical inflection point inflation. https://doi.org/10.1088/1475-7516%2F2021%2F03%2F091

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