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arXiv · 1504.07927

Bouncing Universes in Scalar-Tensor Gravity Models admitting Negative Potentials

B. Boisseau·H. Giacomini·D. Polarski·A. A. Starobinsky
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Abstract

We consider the possibility to produce a bouncing universe in the framework of scalar-tensor gravity models in which the scalar field potential may be negative, and even unbounded from below. We find a set of viable solutions with nonzero measure in the space of initial conditions passing a bounce, even in the presence of a radiation component, and approaching a constant gravitational coupling afterwards. Hence we have a model with a minimal modification of gravity in order to produce a bounce in the early universe with gravity tending dynamically to general relativity (GR) after the bounce.

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B. Boisseau, H. Giacomini, D. Polarski, A. A. Starobinsky. 2015-06-03. Bouncing Universes in Scalar-Tensor Gravity Models admitting Negative Potentials. https://doi.org/10.1088/1475-7516%2F2015%2F07%2F002

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