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Eigenvalues of the Stewart-Lyth equation for inflation with a blue spectrum

Franz E. Schunck·Eckehard W. Mielke
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Abstract

By using the rather stringent nonlinear second order slow-roll approximation, we reconsider the nonlinear second order Abel equation of Stewart and Lyth. We determine a new blue eigenvalue spectrum. Some of the discrete values of the spectral index $n_s$ have consistent fits to the cumulative COBE data as well as to recent ground-base CMB experiments.

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Franz E. Schunck, Eckehard W. Mielke. 2000-06-24. Eigenvalues of the Stewart-Lyth equation for inflation with a blue spectrum. https://doi.org/10.1016/s0370-2693(00)00689-4

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