7:Outer Boundary
3 methods
1. Blended Dirichlet outer boundary conditions.
- Stable evolutions can be obtained!
- Only works for limited cases with exact CC.
2. Perturbative OB PRL 80 (1998) 1812-1815
- Easier than CCM, since perturbative calculations are not expensive, and the matching is not complex.
- Problems are that it needs to be far from the hole ~20M, and we need separate backgrounds from perturbations.
3. Cauchy-characteristic matching (PRL 80 (1998) 3915-3918)
- Works well for simple test cases.