Journal of Statistical Physics, Vol. 75, Nos. 5/6, 1994, p. 839-857.
We study the dynamics of phase ordering in the presence of an external "gravitational" field, namely a field that varies linearly with distance in one direction. Starting from microscopic considerations, we motivate reasonable phenomenological models for cases with nonconserved and conserved order parameter. We present detailed numerical results from our model for the case with conserved order parameter.