COSMOLOGIES WITH MASSIVE NEUTRINOS AND LARGE VALUE OF HUBBLE CONSTANT

If neutrino masses are related by the see-saw relation and m(upsilon mu) similar to 2-3 eV, the tau-neutrino must be allowed to decay. Taking into account recent measurements of the cosmic expansion, which yield h greater than or similar to 0.8, the relativistic products of the decay of upsilon(tau), can delay the equivalence as though it were h similar or equal to 0.3, so providing a transfer function easy to reconcile with LSS data. This result is obtainable also if the actual final contribution of upsilon(mu)'s to the present cosmic density is as low as 4% of the critical density. Still keeping the above neutrino mass scale and h similar to 0.8, alternative choices of physical parameters lead to an earlier equivalence and to a more significant hot component. Altogether, a whole class of models, with hot components characterized by 0.04 less than or similar to Omega(h) less than or similar to 0.2, can be devised, most of which can be expected to be in reasonable agreement with data.