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arXiv · 2012.14429

Stability Conditions for the Horndeski Scalar Field Gravity Model

Cláudio Gomes·Orfeu Bertolami
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Abstract

We constrain the viable models of Horndeski gravity, written in its equivalent Generalised Galileon version, by resorting to the Witten positive energy theorem. We find that the free function $G_3(\phi, X)$ in the Lagrangian is constrained to be a function solely of the scalar field, $G_3(\phi)$, and relations among the free functions are found. Other criterion for stability are also analysed, such as the attractiveness of gravity, the Dolgov-Kawasacki instability and the energy conditions. Some applications for Cosmology are discussed

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Cláudio Gomes, Orfeu Bertolami. 2020-12-27. Stability Conditions for the Horndeski Scalar Field Gravity Model. https://doi.org/10.1088/1475-7516/2022/04/008

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