Cosmological perfect fluids in Gauss-Bonnet gravity

Abstract

In an $n$-dimensional Friedmann-Robertson-Walker metric, it is rigorously shown that any analytical theory of gravity $f(R,\mathcal{G})$, where $R$ is the curvature scalar and $\mathcal{G}$ 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.

8 pages, accepted for publication in International Journal of Geometric Methods in Modern Physics