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arXiv · 2603.00964

Stability and wave dynamics in polytropic Eddington-inspired Born-Infeld gravitating solar plasmas

Abstract

We investigate the influence of nonlinear gravity corrections, arising from the Eddington-inspired Born-Infeld (EiBI) theory on wave dynamics, stability, and energy transport processes in polytropic, viscous, and turbulent solar plasmas. Analytical and numerical analyses of the Jeans-normalized quadratic dispersion relation demonstrate that both the EiBI gravity parameter $(χ)$ and the relative polytropic sound speed $(β)$ independently regulate oscillation frequencies, growth rates, phase velocities, perturbation energy partitioning, and outward acoustic energy flux. Positive $χ$ systematically elevates oscillation frequencies, phase velocities, and outward energy flux level by $\sim$10% relative to the Newtonian predictions, while larger $β$ enhances them by up to 55%, thereby promoting wave propagation and efficient acoustic transport. Conversely, negative $χ$ strengthens gravitational binding and increases damping rates by $\sim$40%, particularly for the \textit{g}-modes. Energy partitioning analyses reveal that the EiBI corrections fundamentally restructure the kinetic-electrostatic-gravitational energy balance. While the Newtonian gravity contributes negligibly ($<$4%), nonzero $χ$ channels up to one-third of oscillation energy into gravitational modes. The modal surface flux calculations further confirm that only the \textit{p}-modes drive outward energy transport (amplification for $χ>0$, suppression for $χ<0$). A direct comparative analysis with four years of SDO/HMI Doppler velocity observations demonstrate a robust theoretical agreement for $χ=3\times10^7$ m$^5$kg$^{-1}$s$^{-2}$, providing the first empirical constraint on the solar EiBI gravity through helioseismology. The findings offer a rigorous framework for advancing our understanding about solar plasma stability, helioseismic signatures, and ambient atmospheric energy transport processes.

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Souvik Das, Pralay Kumar Karmakar. 2026-03-01. Stability and wave dynamics in polytropic Eddington-inspired Born-Infeld gravitating solar plasmas. https://doi.org/10.1103/2djh-d4qh

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