  We show that, assuming the dispersion relation proposed recently by Horava in
the context of quantum gravity, radiation energy density exhibits a peculiar
dependence on the scale factor; the radiation energy density decreases
proportional to a^{-6}. This simple scaling can have an impact on cosmology. As
an example, we show that the resultant baryon asymmetry as well as the
stochastic gravity waves can be enhanced. We also discuss current observational
constraint on the dispersion relation.
