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arXiv · 0803.2674

Thermal and quantum superstring cosmologies

Tristan Catelin-Jullien·Costas Kounnas·Herve Partouche·Nicolaos Toumbas
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Abstract

We consider four dimensional heterotic string backgrounds for which supersymmetry is spontaneously broken via the Scherk-Schwarz mechanism on an internal spatial cycle and by finite temperature effects. We concentrate on initially flat backgrounds with N=4 and N=2 amount of supersymmetry. Thermal and quantum corrections give rise to a non-trivial cosmological evolution. We show that these corrections are under control and calculable due to the underlying no-scale structure of the effective supergravity theory. The effective Friedmann-Hubble equation involves a radiation term ~1/a^4 and a curvature term ~1/a^2, whose coefficients are functions of ratio of the gravitino mass scale to the temperature.

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Tristan Catelin-Jullien, Costas Kounnas, Herve Partouche, Nicolaos Toumbas. 2008-03-18. Thermal and quantum superstring cosmologies. https://doi.org/10.1002/prop.200810553

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