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arXiv · astro-ph/0610389

Running of Running of the Spectral Index and WMAP Three-year data

Qing-Guo Huang
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Abstract

Three-year data of WMAP implies not only a negative running of the spectral index with large absolute value, but also a large positive running of running of the spectral index with order of the magnitude $10^{-2}$. We calculate the running of running in usual inflation model and noncommutative inflation model. A large tensor-scalar ratio $r\geq 1.23$ is needed in order to fit the WMAP data in the noncommutative inflation model, which roughly saturates the observational upper bound on it.

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Qing-Guo Huang. 2006-10-21. Running of Running of the Spectral Index and WMAP Three-year data. https://doi.org/10.1088/1475-7516%2F2006%2F11%2F004

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