We study the effects of anisotropic pressure on the properties of spherically symmetric, gravitationally bound objects. We consider the full generalrelativistic treatment of this problem and obtain exact solutions for various forms of the equation of state connecting the radial and tangential pressures. It is shown that pressure anisotropy can have significant effects on the structure and prope...

in this paper we obtain  exact solutions of the generalized kuramoto-sivashinsky equation, which describes manyphysical processes in motion of turbulence and other unstable process systems.    the methods used  to determine the exact solutions of the underlying equation are the lie group analysis  and the simplest equation method. the solutions obtained are  then plotted.

by means of he's homotopy perturbation method (hpm) an approximate solution of velocity eld is derived for the ow in straight pipes of non-newtonian uid obeying the sisko model. the nonlinear equations governing the ow in pipe are for- mulated and analyzed, using homotopy perturbation method due to he. furthermore, the obtained solutions for velocity eld is graphically sketched and compared w...