Dynamical inflection point inflation. Issue 3 (26th March 2021) - Bai, Yang
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, αs, has branches with both positive and negative values. The positive branch with αs ≳ 0.002 will be tested by the coming cosmic microwave background observations.