Non-resistive electron scattering in thin wires

We review non-resistive normal electron-electron scattering (NEES) and normal electron-phonon scattering (NEPS) at low temperatures, showing that for thin wires, the magnitude of the scattering angle determines the sign of the contribution of non-resistive scattering to the electrical resistivity. Applying these results to large-angle NEES and to small-angle NEPS provides the explanation, at least in part, for two instances of "anomalous" low-temperature data for electron transport recently reported for thin wires and near metallic surfaces.