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arXiv · 2207.13195

Brans-Dicke unimodular gravity

Alexandre M. R. Almeida·Júlio C. Fabris·Mahamadou Hamani Daouda·Richard Kerner·Hermano Velten·Wiliam S. Hipólito-Ricaldi
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Abstract

We propose a unimodular version of the Brans-Dicke theory designed with a constrained Lagrangian formulation. The resulting field equations are traceless. The vacuum solutions in the cosmological background reproduce the corresponding solutions of the usual Brans-Dicke theory but with a cosmological constant term. A perturbative analysis of the scalar modes is performed and stable and unstable configurations appear in contrast with the Brans-Dicke case for which only stable configurations occur. On the other hand, tensorial modes in this theory remains the same as in the traditional Brans-Dicke theory.

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Alexandre M. R. Almeida, Júlio C. Fabris, Mahamadou Hamani Daouda, Richard Kerner, Hermano Velten, Wiliam S. Hipólito-Ricaldi. 2022-07-26. Brans-Dicke unimodular gravity. https://arxiv.org/abs/2207.13195

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