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arXiv · hep-th/0409130

Second-Order Corrections to the Power Spectrum in the Slow-Roll Expansion with a Time-Dependent Sound Speed

Hao Wei·Rong-Gen Cai·Anzhong Wang
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Abstract

We extend Green's function method developed by Stewart and Gong to calculate the power spectrum of density perturbation in the case with a time-dependent sound speed, and explicitly give the power spectrum and spectral index up to second-order corrections in the slow-roll expansion. The case of tachyon inflation is included as a special case.

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Hao Wei, Rong-Gen Cai, Anzhong Wang. 2004-11-03. Second-Order Corrections to the Power Spectrum in the Slow-Roll Expansion with a Time-Dependent Sound Speed. https://doi.org/10.1016/j.physletb.2004.10.034

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