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arXiv · 1906.05693

Cosmological perfect fluids in Gauss-Bonnet gravity

Salvatore Capozziello·Carlo Alberto Mantica·Luca Guido Molinari
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Abstract

In an $n$-dimensional Friedmann-Robertson-Walker metric, it is rigorously shown that any analytical theory of gravity $f(R,{\cal G})$, where $R$ is the curvature scalar and $\cal G$ is the Gauss-Bonnet topological invariant, can be associated to a perfect-fluid stress-energy tensor. In this perspective, dark components of the cosmological Hubble flow can be geometrically interpreted.

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Salvatore Capozziello, Carlo Alberto Mantica, Luca Guido Molinari. 2019-06-23. Cosmological perfect fluids in Gauss-Bonnet gravity. https://doi.org/10.1142/s0219887819501330

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