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Pre-inflationary perturbations spectrum

Giovanni Imponente·Giovanni Montani
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Abstract

In the framework of a flat FLRW model we derive an inflationary regime in which the scalar field, laying on the plateau of its potential, admits a linear time dependence and remains close to a constant value. The behaviour of inhomogeneous perturbations is determined on the background metric in agreement to the "slow-rolling" approximation. We show that the inhomogeneous scales which before inflation were not much greater then the physical horizon, conserve their spectrum (almost) unaltered after the de Sitter phase.

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Giovanni Imponente, Giovanni Montani. 2004-02-16. Pre-inflationary perturbations spectrum. https://doi.org/10.1142/9789812704030_0194

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