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arXiv · 1507.04703

Loop quantum cosmology, non-Gaussianity, and CMB power asymmetry

Ivan Agullo
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Abstract

We argue that the anomalous power asymmetry observed in the cosmic microwave background (CMB) may have originated in a cosmic bounce preceding inflation. In loop quantum cosmology (LQC) the big bang singularity is generically replaced by a bounce due to quantum gravitational effects. We compute the spectrum of inflationary non-Gaussianity and show that strong correlation between observable scales and modes with longer (super-horizon) wavelength arise as a consequence of the evolution of perturbations across the LQC bounce. These correlations are strongly scale dependent and induce a dipole-dominated modulation on large angular scales in the CMB, in agreement with observations.

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Ivan Agullo. 2015-07-16. Loop quantum cosmology, non-Gaussianity, and CMB power asymmetry. https://doi.org/10.1103/physrevd.92.064038

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