Quantum cosmology at finite temperature in superstring theory

Abstract : We study cosmology induced by an ideal superstring gas at finite temperature. The thermal/quantum effects of the string gas generate a nontrivial effective potential at one-loop level. At certain points in the moduli space where generically massive states become massless, the effective potential develops local minima. The latter serve as moduli attractors, which induce time-dependent scalar masses decreasing in cosmological time. As a result, the coherent scalar oscillations dilute before nucleosynthesis, and the cosmological moduli problem is avoided. In particular, we study moduli stabilization in the cases of cosmology induced by i) a maximally supersymmetric heterotic string gas; ii) a gas of type II string compactified on Calabi-Yau three-folds. In case i), the local minima of the potential arise at enhanced gauge symmetry points, which can stabilize all moduli but the dilaton. In case ii), local minima of the effective potential are reached at the loci where 2-spheres or 3-spheres in the Calabi-Yau space shrink to zero size, giving rise to either conifold transitions or non Abelian gauge symmetries. Extra massless states are induced by D-brane wrapping the shrinking spheres, and the stabilized moduli are those controlling the volume of those spheres. In addition, in the two cases we also study respectively the type I dual theory which is maximally supersymmetric and the heterotic dual theory compactified on K3xT2. We show that dual moduli can be stabilized by novel non-perturbative effects implied by duality maps.
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https://pastel.archives-ouvertes.fr/pastel-00733052
Contributor : Lihui Liu <>
Submitted on : Monday, September 17, 2012 - 5:57:48 PM
Last modification on : Wednesday, March 27, 2019 - 4:02:05 PM
Long-term archiving on : Tuesday, December 18, 2012 - 9:06:00 AM

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  • HAL Id : pastel-00733052, version 1

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Lihui Liu. Quantum cosmology at finite temperature in superstring theory. High Energy Physics - Theory [hep-th]. Ecole Polytechnique X, 2012. English. ⟨pastel-00733052⟩

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