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The stability of modified gravity models

Valerio Faraoni·Shahn Nadeau
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Abstract

Conditions for the existence and stability of de Sitter space in modified gravity are derived by considering inhomogeneous perturbations in a gauge-invariant formalism. The stability condition coincides with the corresponding condition for stability with respect to homogeneous perturbations, while this is not the case in scalar-tensor gravity. The stability criterion is applied to various modified gravity models of the early and the present universe.

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Valerio Faraoni, Shahn Nadeau. 2005-11-16. The stability of modified gravity models. https://doi.org/10.1103/physrevd.72.124005

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