3:Description of causal differencing
Canonical coordinate system denoted by (t,xi):Lt=¶/¶t
- Spatial coordinates dragged along tm = anm + bm.
- For quantities defined in (t,xi) basis, Lt = ¶ /¶t .
Introduce new coordinates :
- Time coordinates coincide: .
- Spatial coordinates dragged along normal vector norm nm
- At the beginning of each step, t=t0, we set = xi.