Nucleation in the presence of long-range interactions

We present a theory for nucleation at a first-order phase transition where the mediating forces are long range. We find that the long-range force induces cooperative nucleation and growth processes, and that this feedback mechanism produces a well-defined delay time with a sharp onset in the transformation to the stable phase. Closed-form expressions for the characteristic onset time and width of the transition are developed, in good agreement with numerical and existing experimental results.