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arXiv · hep-th/9706221

Classical Inhomogeneities in String Cosmology

A. Buonanno·K. A. Meissner·C. Ungarelli·G. Veneziano
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Abstract

We generalize previous work on inhomogeneous pre-big bang cosmology by including the effect of non-trivial moduli and antisymmetric-tensor/axion fields. The general quasi-homogeneous asymptotic solution---as one approaches the big bang singularity from perturbative initial data---is given and its range of validity is discussed, allowing us to give a general quantitative estimate of the amount of inflation obtained during the perturbative pre-big bang era. The question of determining early-time ``attractors'' for generic pre-big bang cosmologies is also addressed, and a motivated conjecture is advanced. We also discuss S-duality-related features of the solutions, and speculate on the way an asymptotic T-duality symmetry may act on moduli space as one approaches the big bang.

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A. Buonanno, K. A. Meissner, C. Ungarelli, G. Veneziano. 1997-07-24. Classical Inhomogeneities in String Cosmology. https://doi.org/10.1103/physrevd.57.2543

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