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arXiv · 1112.2785

Non-Gaussian features from the inverse volume corrections in loop quantum cosmology

Li-Fang Li·Rong-Gen Cai·Zong-Kuan Guo·Bin Hu
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Abstract

In this paper we study the non-Gaussian features of the primordial fluctuations in loop quantum cosmology with the inverse volume corrections. The detailed analysis is performed in the single field slow-roll inflationary models. However, our results reflect the universal characteristics of bispectrum in loop quantum cosmology. The main corrections to the scalar bispectrum come from two aspects: one is the modifications to the standard Bunch-Davies vacuum, the other is the corrections to the background dependent variables, such as slow-roll parameters. Our calculations show that the loop quantum corrections make $f_{\rm NL}$ of the inflationary models increase 0.1%. Moreover, we find that two new shapes arise, namely $\mathcal F_{1}$ and $\mathcal F_{2}$. The former gives a unique loop quantum feature which is less correlated with the local, equilateral and single types, while the latter is highly correlated with the local one.

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Li-Fang Li, Rong-Gen Cai, Zong-Kuan Guo, Bin Hu. 2012-09-23. Non-Gaussian features from the inverse volume corrections in loop quantum cosmology. https://doi.org/10.1103/physrevd.86.044020

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