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arXiv · 1303.3241

Scale-Invariant Curvature Fluctuations from an Extended Semiclassical Gravity

Nicola Pinamonti·Daniel Siemssen
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Abstract

We present an extension of the semiclassical Einstein equations which couples n-point correlation functions of a stochastic Einstein tensor to the n-point functions of the quantum stress-energy tensor. We apply this extension to calculate the quantum fluctuations during an inflationary period, where we take as a model a massive conformally coupled scalar field on a perturbed de Sitter space and describe how a renormalization independent, almost-scale-invariant power spectrum of the scalar metric perturbation is produced. Furthermore, we discuss how this model yields a natural basis for the calculation of non-Gaussianities of the considered metric fluctuations.

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Nicola Pinamonti, Daniel Siemssen. 2015-03-07. Scale-Invariant Curvature Fluctuations from an Extended Semiclassical Gravity. https://doi.org/10.1063/1.4908127

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