Theory of Viscosity in Nearly Ferromagnetic Fermi Liquids

A recent theory of transport processes in nearly ferromagnetic Fermi liquids, based on the concept of particle scattering from persistent spin fluctuations, or paramagnons, is extended to calculate the viscosity coefficient $\eta$. The theoretical temperature dependence, in which $\eta$ falls off increasingly less rapidly than $T^{-2\mathrm{}}$ as $T$ is increased from absolute zero, fits well that of the observed viscosity of liquid ${\mathrm{He}}^3$.