TIME-DEPENDENT LOCAL FIELD DISTRIBUTION AND REMANENT MAGNETIZATION IN THE SK-SPIN GLASS

A Fokker-Planck type equation is derived for the distribution of local fields in the SK-spin glass. It is obtained from an exact hierarchy of similar equations for distribution functions of higher dimension. A modified Kirkwood superposition approximation is used as closure. This approach respects exact sum rules. Numerical integration yields for a fully magnetized initial state a finite remanent magnetization at zero temperature and a slow decay of the magnetization at finite temperatures. For temperatures above the critical point the replica symmetric solution is approached at late times. © 1990 Springer-Verlag.