The Tricomi equation can be expressed in symmetric positive form. Admissible boundary conditions assure existence and uniqueness of solutions. In this paper it is shown what boundary conditions are ...

The Einstein field equations are a system of second order, non-linear, coupled differential equations in 4 variables. As you can imagine, solving such a system is not easy. If the system possesses a ...

Differential equations are equations that contain derivatives. The equations are used in calculus to describe relationships among one or more variables. A solution to any series of equations can be ...