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arXiv · 2412.01873

Solar GES-structure modified with EiBI gravity

Abstract

In the post-Newtonian era, the Eddington-inspired Born-Infeld (EiBI) theory, considered as an improved modification of the Einsteinian general relativity formalism in the weak field regime (non-relativistic), has enabled us to study the dynamics of dense astroobjects in light of the modified gravitational effects. This EiBI theory imparts a new shape to the usual gravitational Poisson equation through the addition of a cosmological correction factor, termed as the EiBI gravity parameter. A systematic inclusion of this gravity in the basic structure equation could lead to a realistic picture of the existing solar models free from any end-stage singularity. A theoretic model is accordingly proposed to investigate the effect of the EiBI gravity on the Gravito-Electrostatic Sheath (GES) formalism of the equilibrium solar plasma structure. This study shows that the GES-based solar plasma dynamics is noticeably modified against the previously reported Newtonian GES-model studies. An equilibrium bounded solution for the solar self-gravity shows the EiBI-modified solar surface boundary (SSB) to exist at a new helio-centric radial location $\xi = 4$ (on the Jeansean scale). It is found that the EiBI gravity shifts the present SSB outwards by 14.28% relative to the original Newtonian SSB. The EiBI-modified gravity effects on diverse relevant solar parameters, such as the gravito-electrostatic potentials, fields, and Mach numbers, are illustratively analyzed. It is anticipated that our analyses could be applied further to see the solar plasma equilibrium and fluctuation dynamics in realistically modified post-Newtonian gravity environments on both the bounded (interior) and unbounded (exterior) solar plasma scales.

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BibTeXRIS

Souvik Das, Pralay Kumar Karmakar. 2024-12-02. Solar GES-structure modified with EiBI gravity. https://doi.org/10.1016/j.cjph.2024.05.008

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