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arXiv · hep-ph/0304161

Inflation with a running spectral index in supergravity

M. Kawasaki·Masahide Yamaguchi·Jun'ichi Yokoyama
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Abstract

The first year Wilkinson Microwave Anisotropy Probe data favors primordial adiabatic fluctuation with a running spectral index with $\ns >1$ on a large scale and $\ns <1$ on a smaller scale. The model building of inflation that predicts perturbations with such a spectrum is a challenge, because most models predict fluctuations with either $\ns >1$ (hybrid inflation) or $\ns <1$ (new, chaotic, or topological inflation). We give a sensible particle physics model in supergravity that accommodates the desired running of the spectral index using double inflation.

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M. Kawasaki, Masahide Yamaguchi, Jun'ichi Yokoyama. 2003-06-18. Inflation with a running spectral index in supergravity. https://doi.org/10.1103/physrevd.68.023508

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