The old strong-gravity screwball test didn't work because the 3-metric was degenerate. The current Minkowski screwball test works, but it's not really an effective test of a 3+1 split -- the lapse is imaginary and there is no shift. We need better tests for these.
The old strong-gravity screwball test didn't work because the 3-metric was degenerate. The current Minkowski screwball test works, but it's not really an effective test of a 3+1 split -- the lapse is imaginary and there is no shift. We need better tests for these.