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On the initial regime of pre-big bang cosmology

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 نشر من قبل Maurizio Gasperini
 تاريخ النشر 2017
  مجال البحث فيزياء
والبحث باللغة English
 تأليف M. Gasperini




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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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