Transport anomalies and marginal-Fermi-liquid effects at a quantum critical point

The conductivity and the tunneling density of states of disordered itineran t electrons in the vicinity of a ferromagnetic transition at low temperatur e are discussed. Critical fluctuations lead to nonanalytic frequency and te mperature dependencies that are distinct from the usual long-time tail effe cts in a disordered Fermi liquid. The crossover between these two types of behavior is proposed as an experimental check of recent theories of the qua ntum ferromagnetic critical behavior In addition, the quasiparticle propert ies at criticality are shown to be those of a marginal Fermi liquid.