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arXiv · 2409.01468

A new framework for cosmological expansion in a reformulated Newtonian-Like gravity with variable G

Felipe S. Escórcio·Júlio C. Fabris·Júnior D. Toniato·Hermano Velten
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Abstract

A Newtonian-like theory inspired by the Brans-Dicke gravitational Lagrangian has been recently proposed in Ref. arXiv:2009.04434(v4). We propose here a new variant of this theory such that the usual Newtonian second law is preserved. The cosmological solutions are analysed and accelerated background expansion can be obtained even in a pure matter dominated universe. This happens due to the dynamic character of the effective gravitational coupling which is sourced by a time evolving scalar field . We also analyse the matter density perturbations and find they exhibit an enhanced growth in comparison with the usual Newtonian like behavior in Einstein-de Sitter model.

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Felipe S. Escórcio, Júlio C. Fabris, Júnior D. Toniato, Hermano Velten. 2024-09-02. A new framework for cosmological expansion in a reformulated Newtonian-Like gravity with variable G. https://arxiv.org/abs/2409.01468

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