Classes of exact Einstein–Maxwell solutions

New classes of exact multistring solutions in curved spacetimes.

We find new classes of exact string solutions in a variety of curved backgrounds. They include stationary and dynamical (open, closed, straight, finitely and infinitely long) strings as well as multi-string solutions, in terms of elliptic functions. The physical properties, string length, energy and pressure are computed and analyzed. In anti de Sitter spacetime, the solutions describe an infin...

Classes of Exact Solutions to the Teukolsky Master Equation

The Teukolsky Master Equation describes perturbations of the Kerr metric in linear approximation. It admits separation of variables, thus yielding the Teukolsky Radial Equation and the Teukolsky Angular Equation. We present here a unified description of all classes of exact solutions to these equations in terms of the confluent Heun functions and the confluent Heun polynomials. Large classes of...

Classes of Exact Solutions to Regge-Wheeler and Teukolsky Equations

The Regge-Wheeler equation describes axial perturbations of Schwarzschild metric in linear approximation. Teukolsky Master Equation describes perturbations of Kerr metric in the same approximation. We present here unified description of all classes of exact solutions to these equations in terms of the confluent Heun’s functions. Special attention is paid to the polynomial solutions, which yield...

Exact solutions of nonlinear interval Volterra integral equations

EXACT SOLUTIONS FOR FLOW OF A SISKO FLUID IN PIPE

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...