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arXiv · hep-th/9610107

Cosmological Solutions in String Theories

H. Lu·S. Mukherji·C. N. Pope·K. -W. Xu
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Abstract

We obtain a large class of cosmological solutions in the toroidally-compactified low energy limits of string theories in $D$ dimensions. We consider solutions where a $p$-dimensional subset of the spatial coordinates, parameterising a flat space, a sphere, or an hyperboloid, describes the spatial sections of the physically-observed universe. The equations of motion reduce to Liouville or $SL(N+1,R)$ Toda equations, which are exactly solvable. We study some of the cases in detail, and find that under suitable conditions they can describe four-dimensional expanding universes. We discuss also how the solutions in $D$ dimensions behave upon oxidation back to the $D=10$ string theory or $D=11$ M-theory.

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H. Lu, S. Mukherji, C. N. Pope, K. -W. Xu. 1996-11-05. Cosmological Solutions in String Theories. https://doi.org/10.1103/physrevd.55.7926

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