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arXiv · 1408.0398

Study of Antigravity in an F(R) Model and in Brans-Dicke Theory with Cosmological Constant

V. K. Oikonomou·N. Karagiannakis
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Abstract

We study antigravity, that is having an effective gravitational constant with a negative sign, in scalar-tensor theories originating from $F(R)$-theory and in a Brans-Dicke model with cosmological constant. For the $F(R)$ theory case, we obtain the antigravity scalar-tensor theory in the Jordan frame by using a variant of the Lagrange multipliers method and we numerically study the time dependent effective gravitational constant. As we shall demonstrate by using a specific $F(R)$ model, although there is no antigravity in the initial model, it might occur or not in the scalar-tensor counterpart, mainly depending on the parameter that characterizes antigravity. Similar results hold true in the Brans-Dicke model.

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V. K. Oikonomou, N. Karagiannakis. 2014-08-02. Study of Antigravity in an F(R) Model and in Brans-Dicke Theory with Cosmological Constant. https://arxiv.org/abs/1408.0398

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