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arXiv · 1402.6968

Scale-dependent power spectrum from initial excited-de Sitter modes

E. Yusofi·M. Mohsenzadeh
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Abstract

In this paper, we calculate corrections of scalar perturbations spectra resulting from excited-de Sitter modes as the nontrivial initial states. To obtain these modes, we consider the asymptotic expansion of the Hankel functions up to the higher order of 1/kτ . Actually the Planck and WMAP data impose some constrains on the Hankel function index. These observational constraints and back-reaction effects stimulate us to use excited-de Sitter modes. Finally, we nominate these nontrivial general solutions as the fundamental mode functions during inflation and we calculate the corrected form of scale-dependent power spectrum with trans-Planckian corrections, and in de Sitter space-time limit the results reduce to the scale-invariant power spectrum.

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E. Yusofi, M. Mohsenzadeh. 2014-09-26. Scale-dependent power spectrum from initial excited-de Sitter modes. https://doi.org/10.1007/jhep09(2014)020

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