Lithium and the nature of dark matter

Limits on the value of critical temperature of the quark-hadron phase transition, evaluated by chiral perturbation calculations, are discussed in the frame of primordial nucleosynthesis. The yield of lithium is compatible with the Pop II data in approximately the same range as in the case of homogeneous baryonic density models. Taking into account various factors in the search for the initial abundance of the cosmological isotopes, it appears very likely that most of the baryonic matter is not luminous and that most of the dark matter is non-baryonic. However pushing all the uncertainties to their extremes, it seems also that we do not necessarily require baryonic dark matter and, we do not necessarily require non-baryonic dark matter. The uncertainty in the value of the Hubble parameter remains one of the largest source of uncertainty in this analysis