Undoing the twist: the Ho\v{r}ava limit of Einstein-aether
  We show that Ho\v{r}ava gravity can be obtained from Einstein-aether theory
in the limit that the twist coupling constant goes to infinity, while holding
fixed the expansion, shear and acceleration couplings. This limit helps to
clarify the relation between the two theories, and allows Ho\v{r}ava results to
be obtained from Einstein-aether ones. The limit is illustrated with several
examples, including rotating black hole equations, PPN parameters, and
radiation rates from binary systems.
