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Slow-roll reconstruction for running spectral index

Qing-Guo Huang
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Abstract

We not only reconstruct the slow-roll parameters for fit to the running spectral index from WMAP three-year data in the usual slow-roll inflation model and noncommutative inflation model, but also investigate the evolution of these slow-roll parameters. Requiring slow-roll inflation lasts more than 20 e-folds after CMB scales leave the horizon suggests that the potential at the last stage of inflation takes the form $V(ϕ)=V_0(1+{η_c\over 2}{(ϕ-ϕ_c)^2\over M_p^2})$, where $η_c$ is a constant. A natural mechanism to end inflation at $ϕ=ϕ_c$ is hybrid type inflation.

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Qing-Guo Huang. 2007-07-02. Slow-roll reconstruction for running spectral index. https://doi.org/10.1103/physrevd.76.043505

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