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An inflation model with large variations in spectral index

Bo Feng·Mingzhe Li·Ren-Jie Zhang·Xinmin Zhang
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Abstract

Recent fits of cosmological parameters by the Wilkinson Microwave Anisotropy Probe (WMAP) measurement favor a primordial scalar spectrum with varying index. This result, if stands, could severely constrain inflation model buildings. Most extant slow-roll inflation models allow for only a tiny amount of scale variations in the spectrum. We propose in this paper an extra-dimensional inflation model which is natural theoretically and can generate the required variations of the spectral index as implied by the WMAP for suitable choices of parameters.

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Bo Feng, Mingzhe Li, Ren-Jie Zhang, Xinmin Zhang. 2003-08-13. An inflation model with large variations in spectral index. https://doi.org/10.1103/physrevd.68.103511

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