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arXiv · 1408.2339

Small Field Coleman-Weinberg Inflation driven by Fermion Condensate

Satoshi Iso·Kazunori Kohri·Kengo Shimada
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Abstract

We revisit the small field Coleman-Weinberg (CW) inflation, which has the following two problems. First, the smallness of the slow roll parameter $ε$ requires the inflation scale to be very low. Second, the spectral index $n_s \approx1+2 η$ tends to become smaller compared to the observed value. In this letter, we consider two possible effects on the dynamics of inflation: radiatively generated non-minimal coupling to gravity $ξϕ^2 {\cal R}$ and condensation of fermions coupled to the inflaton as $ϕ\barψψ$. We show that the fermion condenate can solve the above problems.

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Satoshi Iso, Kazunori Kohri, Kengo Shimada. 2015-02-08. Small Field Coleman-Weinberg Inflation driven by Fermion Condensate. https://doi.org/10.1103/physrevd.91.044006

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