A common origin for the resistivity of Cd${}_2$Re${}_2$O${}_7$, the cuprates, and Sr${}_2$RuO${}_4$?

We propose an explanation for the temperature dependence of the resistivity of Cd${}_2$Re${}_2$O${}_7$, including the regime above the structural phase transition at $T$=200 ${}^o$K. The mechanism involved relies on the existence of a strong van Hove singularity close to the Fermi surface, which is evidenced by relevant band structure calculations. The same mechanism has successfully described the $T$-linear resistivity of the cuprates and Sr${}_2$RuO${}_4$, and the one-particle scattering rate in the former materials, as corroborated by recent experiments. We describe a few predictions for Cd${}_2$Re${}_2$O${}_7$ and Cd${}_2$Os${}_2$O${}_7$.