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arXiv · 0809.4312

Short Distance Physics and Initial State Effects on the CMB Power Spectrum

Moslem Zarei
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Abstract

We investigate a modification in the action of inflaton due to noncommutativity leads to a nonstandard initial vacuum and oscillatory corrections in the initial power spectrum. We show that the presence of these oscillations causes a drop in the WMAP $χ^{2}$ about $Δχ^{2}\sim 8.5$. As a bonus, from the parameter estimation done in this work, we show that the noncommutative parameters can be precisely bound to $10^{16}$ GeV or $10^{4}$ GeV depending on the inflation scale.

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Moslem Zarei. 2008-11-23. Short Distance Physics and Initial State Effects on the CMB Power Spectrum. https://doi.org/10.1103/physrevd.78.123502

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