Linear theory predictions for the matter power spectra with massive neutrinos, normalized by the corresponding case of massless neutrinos. The cosmological parameters considered are those used for our simulations (see Sect. 4); the neutrino mass range is indicated in the figure. Different colors (and similar line styles) show the evolution in redshift for z = 0,2,4, respectively, as a function of the neutrino mass. The yellow area corresponds to values of k < k_{nr,Mν = 0.8 eV}, where a linear description for the neutrino evolution is sufficient; the gray zone highlights the range of k approximately covered by the one-dimensional flux power spectrum obtained from the Lyα BOSS survey.