I had read about this experiment before, of course, and there is even a 2003 movie "21 grams". There are a lot of methodological flaws in the experiments, beginning with a too-small sample. The hypothesis itself is flawed, blurring together metaphysics and physics.

The biblcal image of death is "falling asleep." The flight of the soul from the body after death owed a lot more to Plato than to Moses...