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arXiv · 2109.08687

Stellar structure in a Newtonian theory with variable $G$

Júlio C. Fabris·Túlio Ottoni·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. For static configurations the gravitational coupling acquires an intrinsic spatial dependence within the matter distribution. Therefore, the interior of astrophysical configurations may provide a testable environment for this approach as long as no screening mechanism is evoked. In this work we focus on the stellar hydrostatic equilibrium structure in such varying $G$ scenario. A modified Lane-Emden equation is presented and its solutions for various values of the polytropic index are discussed. The role played by the theory parameter $\omega$, the analogue of the Brans-Dicke parameter, on the physical properties of stars is discussed.

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Júlio C. Fabris, Túlio Ottoni, Júnior D. Toniato, Hermano Velten. 2021-09-17. Stellar structure in a Newtonian theory with variable $G$. https://arxiv.org/abs/2109.08687

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