Key points are not available for this paper at this time.
We consider phase transitions in systems where the field conjugate to the order parameter is static and random. It is demonstrated that when the order parameter has a continuous symmetry, the ordered state is unstable against an arbitrarily weak random field in less than four dimensions. The borderline dimensionality above which mean-field-theory results hold is six.
Imry et al. (Mon,) studied this question.