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arXiv · 1612.06074

Anisotropic homogeneous string cosmology with two-loop corrections

F. Naderi·A. Rezaei-Aghdam
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Abstract

The two-loop (order $α'$) $β$-function equations, which are equivalent to the equations of motion of $α'$-corrected string effective action, are considered for anisotropic homogeneous space-times. These equations are solved for all Bianchi-type models in two schemes of effective action, namely $R^2$ and Gauss-Bonnet schemes with zero cosmological constant and then the metric, dilaton and $B$-field are found at $α'$ perturbative corrections.

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F. Naderi, A. Rezaei-Aghdam. 2017-10-18. Anisotropic homogeneous string cosmology with two-loop corrections. https://doi.org/10.1016/j.nuclphysb.2017.08.005

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