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arXiv · 1908.10176

Cosmological perfect fluids in higher-order gravity

Salvatore Capozziello·Carlo Alberto Mantica·Luca Guido Molinari
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Abstract

We prove that in Robertson-Walker space-times (and in generalized Robertson-Walker spacetimes of dimension greater than 3 with divergence-free Weyl tensor) all higher-order gravitational corrections of the Hilbert-Einstein Lagrangian density $F(R,\square R, ... , \square^k R)$ have the form of perfect fluids in the field equations. This statement definitively allows to deal with dark energy fluids as curvature effects.

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Salvatore Capozziello, Carlo Alberto Mantica, Luca Guido Molinari. 2019-08-27. Cosmological perfect fluids in higher-order gravity. https://doi.org/10.1007/s10714-020-02690-2

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