The gravitational field equations of a twisted skyrmion string: Numerical solution

Abstract

We study nonlinear sigma model, especially Skyrme model with twist: twisted Skyrmion string where twist term, mkz, is indicated in vortex solution. To add gravity, we replace gμv in Lagrangian system with a space-time metric tensor, gμv which in view of the time-independence and cylindrical symmetry of the assumed vortex solution is taken to be a function of r alone. We use ode45 for numerical calculation, i.e. a tool box in Matlab to solve coupled Einstein field equations which have ordinary differential equations (ODE) form.