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arXiv · 2004.02080

Stability of the Einstein Static Universe in $4 D$ Gauss-Bonnet Gravity

Shou-Long Li·Puxun Wu·Hongwei Yu
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Abstract

By rescaling the Gauss-Bonnet (GB) coupling constant $α\rightarrow α/(D-4)$ and considering the $D \rightarrow 4$ limit, the GB gravity gives rise to nontrivial modification of general relativity in four dimensions. In this work, we investigate the realization of the emergent universe scenario in the $4 D$ GB gravity. First, we obtain the Einstein static universe filled with a perfect fluid. Then, we show that both spatially closed and open universes can be stable against both homogeneous and inhomogeneous scalar perturbations simultaneously.

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Shou-Long Li, Puxun Wu, Hongwei Yu. 2020-04-13. Stability of the Einstein Static Universe in $4 D$ Gauss-Bonnet Gravity. https://arxiv.org/abs/2004.02080

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