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arXiv · 1812.11037

Role of $σR^{2}+γR_{μν}T^{μν}$ Model on Anisotropic Polytropes

M. Sharif·Arfa Waseem
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Abstract

This paper analyzes the anisotropic stellar evolution governed by a polytropic equation of state in the framework of $f(R,T,Q)$ gravity, where $Q=R_{ab}T^{ab}$. We construct the field equations, hydrostatic equilibrium equation and trace equation to obtain their solutions numerically under the influence of $σR^{2}+γQ$ gravity model, where $σ$ and $γ$ are arbitrary constants. We examine the dependence of various physical characteristics such as radial/tangential pressure, energy density, anisotropic factor, total mass and surface redshift for specific values of the model parameters. The physical acceptability of the considered model is discussed by verifying the validity of energy conditions, causality condition, and adiabatic index. We also study the effects arising due to the strong non-minimal matter-curvature coupling on anisotropic polytropes. It is found that the polytropic stars are stable and their maximum mass point lies within the required observational Chandrasekhar limit.

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M. Sharif, Arfa Waseem. 2018-12-18. Role of $σR^{2}+γR_{μν}T^{μν}$ Model on Anisotropic Polytropes. https://doi.org/10.1142/s021827181950007x

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