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On the Stability of a class of Modified Gravitational Models

Guido Cognola·Monica Gastaldi·Sergio Zerbini
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Abstract

Motivated by the dark energy issue, a minisuperspace approach to the stability for modified gravitational models in a four dimensional cosmological setting are investigated. Specifically, after revisiting the $f(R)$ case, $R$ being the Ricci curvature, we present a stability condition around a de Sitter solution valid for modified gravitational models of generalized Gauss-Bonnet type $F(R,G,Q)$, $G$ and $Q$ being the Gauss-Bonnet and quadratic Riemann invariants respectively. A generalization to higher order invariants is mentioned.

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Guido Cognola, Monica Gastaldi, Sergio Zerbini. 2007-05-09. On the Stability of a class of Modified Gravitational Models. https://doi.org/10.1007/s10773-007-9516-x

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