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arXiv · 2504.01710

Fluid and scalar field representations in the Brans-Dicke theory: cosmological scenarios

Tiago H. B. Alves·Júlio C. Fabris·Luiz Filipe Guimarães
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Abstract

The Brans-Dicke scalar-tensor cosmological models are studied in both Einstein and Jordan frames, using hydrodynamical and self-interacting scalar field representations of the energy-momentum tensor, leading to the same background solutions. The main features of the corresponding cosmological scenarios are determined. In many cases, we identify a transition from decelerated to accelerated regimes. The properties of the self-interacting scalar field, including the corresponding potential, are determined. Finally, some possible realistic configurations are analyzed.

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Tiago H. B. Alves, Júlio C. Fabris, Luiz Filipe Guimarães. 2025-04-02. Fluid and scalar field representations in the Brans-Dicke theory: cosmological scenarios. https://arxiv.org/abs/2504.01710

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