Newtonian and post Newtonian expansionfree fluid evolution in f(R) gravity

  title={Newtonian and post Newtonian expansionfree fluid evolution in f(R) gravity},
  author={M. Sharif and H. R. Kausar},
  journal={Astrophysics and Space Science},
We consider a collapsing sphere and discuss its evolution under the vanishing expansion scalar in the framework of f(R) gravity. The fluid is assumed to be locally anisotropic which evolves adiabatically. To study the dynamics of the collapsing fluid, Newtonian and post Newtonian regimes are taken into account. The field equations are investigated for a well-known f(R) model of the form R+δR2 admitting Schwarzschild solution. The perturbation scheme is used on the dynamical equations to explore… Expand
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