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Cosmic Microwave Background anisotropies and extra dimensions in String Cosmology

A. Melchiorri·F. Vernizzi·R. Durrer·G. Veneziano
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Abstract

A recently proposed mechanism for large-scale structure in string cosmology --based on massless axionic seeds-- is further analyzed and extended to the acoustic-peak region. Existence, structure, and normalization of the peaks turn out to depend crucially on the overall evolution of extra dimensions during the pre-big bang phase: conversely, precise cosmic microwave background anisotropy data in the acoustic-peak region will provide, within the next decade, a window on string-theory's extra dimensions before their eventual compactification.

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A. Melchiorri, F. Vernizzi, R. Durrer, G. Veneziano. 1999-11-04. Cosmic Microwave Background anisotropies and extra dimensions in String Cosmology. https://doi.org/10.1103/physrevlett.83.4464

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