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Intermediate inflation in light of the three-year WMAP observations

John D Barrow·Andrew R Liddle·Cédric Pahud
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Abstract

The three-year observations from the Wilkinson Microwave Anisotropy Probe have been hailed as giving the first clear indication of a spectral index n_s<1. We point out that the data are equally well explained by retaining the assumption n_s=1 and allowing the tensor-to-scalar ratio r to be non-zero. The combination n_s=1 and r>0 is given (within the slow-roll approximation) by a version of the intermediate inflation model with expansion rate H(t) \propto t^{-1/3}. We assess the status of this model in light of the WMAP3 data.

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John D Barrow, Andrew R Liddle, Cédric Pahud. 2006-12-19. Intermediate inflation in light of the three-year WMAP observations. https://doi.org/10.1103/physrevd.74.127305

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