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arXiv · 1412.3017

Impact of Extended Starobinsky Model on Evolution of Anisotropic, Vorticity-free Axially Symmetric Sources

Ifra Noureen·Abdul Aziz Bhatti·M. Zubair
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Abstract

We study the implications of $R^n$ extension of Starobinsky model on dynamical instability of Vorticity-free axially symmetric gravitating body. The matter distribution is considered to be anisotropic for which modified field equations are formed in context of $f(R)$ gravity. In order to achieve the collapse equation, we make use of the dynamical equations, extracted from linearly perturbed contracted Bianchi identities. The collapse equation carries adiabatic index $Γ$ in terms of usual and dark source components, defining the range of stability/insatbility in Newtonian (N) and post-Newtonian (pN) eras. It is found that supersymmetric supergravity $f(R)$ model represents the more practical substitute of higher order curvature corrections.

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Ifra Noureen, Abdul Aziz Bhatti, M. Zubair. 2015-04-09. Impact of Extended Starobinsky Model on Evolution of Anisotropic, Vorticity-free Axially Symmetric Sources. https://doi.org/10.1088/1475-7516%2F2015%2F02%2F033

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