Problem Description

3+1 method
 The four dimensional spacetime is split into 3 dimensional
hypersurfaces which evolve in time. Breaking spacetime up this way
gives us 10 nonlinear PDE's to solve:
 4 Initial Value Equations (Elliptic)
 6 Coupled Evolution Equations (Hyperbolic)
.

Time Evolution
 The evolution equations that this code solves are as follows:
NOTE:
In Classical Physics evolutions are dictated by momentum and
position variables. Numerical Relativity uses the extrinsic
curvature,
to act like
the momentum, and the metric to act as the position.