Maximum Metallic Resistance in Thin Wires

It is argued that electronic states should be localized in any wire whose impurity resistance is greater than about 10 k\ensuremath{\Omega}. At sufficiently low temperatures this will lead to a ${T}^{\ensuremath{-}2}$ increase in resistance because one-dimensional phonons or excited electrons are needed to cause transitions between localized states. An estimate is made of the temperature needed to observe this effect.