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arXiv · 1707.05763

On the initial regime of pre-big bang cosmology

M. Gasperini
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Abstract

The production of a background of super-horizon curvature perturbations with the appropriate (red) spectrum needed to trigger the cosmic anisotropies observed on large scales is associated, in the context of pre-big bang inflation, with a phase of growing string coupling. The extension towards the past of such a phase is not limited in time by the dynamical backreaction of the quantum perturbations of the cosmological geometry and of its sources. A viable, slightly red spectrum of scalar perturbations can thus be the output of an asymptotic, perturbative regime which is well compatible with an initial string-vacuum state satisfying the postulate of "Asymptotic Past Triviality".

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M. Gasperini. 2017-07-18. On the initial regime of pre-big bang cosmology. https://doi.org/10.1088/1475-7516%2F2017%2F09%2F001

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