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Phases of Brans-Dicke cosmology(II):Matter from NS-NS sector

Sunggeun Lee·Chanyong Park·Sang-Jin Sin
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Abstract

We study the cosmology of the Brans-Dicke(BD) theory coupled to perfect fluid type matter. In our previous works, the case where matter is coming from the Ramond-Ramond sector of the string theory was studied. Here, we study the case where matter is coming from the NS-NS sector. Exact solutions are found and the cosmology is classified according to the values of $γ$, the parameter of the equation of state and $ω$, Brans-Dicke parameter. We find taht, in string frame, there are solutions without singularity for some ranges of $γ$ and $ω$. In Einstein frame, however, all solutions are singular.

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Sunggeun Lee, Chanyong Park, Sang-Jin Sin. 1999-09-03. Phases of Brans-Dicke cosmology(II):Matter from NS-NS sector. https://arxiv.org/abs/gr-qc/9909011

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