Friedmann dynamics recovered from compactified Einstein-Gauss-Bonnet cosmology

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In this paper cosmological dynamics in Einstein-Gauss-Bonnet gravity with a perfect fluid source in arbitrary dimension is studied.

• A systematic analysis is performed for the case that the theory does not admit maximally symmetric solutions.
• Considering two independent scale factors, namely one for the three dimensional space and one for the extra dimensional space, is found that a regime exists where the two scale factors tend to a constant value via damped oscillations for not too negative pressure of the fluid, so that asymptotically the evolution of the $(3+1)$-dimensional Friedmann model with perfect fluid is recovered.
• At last, it is worth emphasizing that the present numerical results strongly support a 't Hooft-like interpretation of the parameter $1/D$ (where $D$ is the number of extra dimensions) as a small expansion parameter in very much the same way as it happens in the large $N$ expansion of gauge theories with $1/N$.