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arXiv · 1405.1378

Stability of a Class of Non-Static Axial Self-Gravitating Systems in $f(R)$ Gravity

M. Sharif·Z. Yousaf
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Abstract

In this paper, we analyze stability regions of a non-static restricted class of axially symmetric spacetime with anisotropic matter distribution. We consider $f(R)=R+εR^2$ model and assume hydrostatic equilibrium of the axial self-gravitating system at large past time. Considering perturbation from hydrostatic phase, we develop dynamical as well as collapse equations and explore dynamical instabilities at Newtonian and post-Newtonian regimes. It is concluded with the help of stiffness parameter, $Γ_1$, that radial profile of physical parameters like pressure anisotropy, energy density and higher curvature terms of the $f(R)$ model affect the instability ranges.

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M. Sharif, Z. Yousaf. 2014-06-03. Stability of a Class of Non-Static Axial Self-Gravitating Systems in $f(R)$ Gravity. https://doi.org/10.1007/s10509-014-1985-9

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