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arXiv · hep-th/9605176

Back Reaction and Graceful Exit in String Inflationary Cosmology

Soo-Jong Rey
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Abstract

Classical string cosmology consists of two branches related to each other by scale-factor duality: a super-inflation branch and a Friedmann-Robertson-Walker (FRW) branch. Curvature and string coupling singularity separates the two branches, hence posing `graceful exit problem' to super-inflationary string cosmology. In an exactly soluble two-dimensional compactification model it is shown that quantum back reaction retards curvature and string coupling growth and connects the super-inflation branch to the FRW branch without encountering a singularity. This may offer an attractive solution to the `graceful exit problem' in string inflationary cosmology.

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Soo-Jong Rey. 1996-05-23. Back Reaction and Graceful Exit in String Inflationary Cosmology. https://doi.org/10.1103/physrevlett.77.1929

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