Model system for slow dynamics

Systems whose dynamics are described by a quasilogarithmic or stretched-exponential time dependence are usually fitted by models which use disorder to create a distribution of relaxation times. Here we describe a model which decays slowly towards equilibrium but does not require disorder to provide the slow dynamics. The model consists of a spin system with the spins interacting via the dipole-dipole interaction. The model is able to replicate the more pronounced features observed in the magnetization decay of magnetic systems and high-temperature superconductors.