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arXiv · 1703.03060

Repulsive gravity induced by a conformally coupled scalar field implies a bouncing radiation-dominated universe

V. Antunes·M. Novello
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Abstract

In the present work we revisit a model consisting of a scalar field with a quartic self-interaction potential non-minimally (conformally) coupled to gravity [1]. When the scalar field vacuum is in a broken symmetry state, an effective gravitational constant emerges which, in certain regimes, can lead to gravitational repulsive effects when only ordinary radiation is coupled to gravity. In this case, a bouncing universe is shown to be the only cosmological solution admissible by the field equations when the scalar field is in such a broken symmetry state.

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V. Antunes, M. Novello. 2017-03-08. Repulsive gravity induced by a conformally coupled scalar field implies a bouncing radiation-dominated universe. https://doi.org/10.1007/s10714-017-2219-6

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