TERRESTRIAL, ASTROPHYSICAL AND COSMOLOGICAL IMPLICATIONS OF A BACKGROUND NEUTRINO DENSITY

Scalar Fields have been a feature of this 2003 COSPA symposium. In this paper we will investigate the consequences of coupling scalar fields to the neutrinos to generate, or modify, neutrino masses. This will lead to the model proposed by three of us, in which the mass of a neutrino depends on the local density of neutrinos. This leads to the production of neutrino clouds, where the effective mass of the neutrino is less than its mass in free space. It is possible to extend the standard model to incorporate an interaction of a scalar field with just the neutrinos. Such an interaction is induced by higher dimensional coupling's, scaled at the Planck Mass. If this scalar field coupled to the neutrinos is also the field responsible for quintessence, we are lead to the model proposed for dark energy by Ref.3. One possible consequence of the neutrino clouds is that, if the earth lives in such a cloud, the flux of cosmic ray neutrinos required to produce the Ultra High Energy Cosmic Rays (UHECRs) can be reduced to reasonable proportions, thus giving limits on the local neutrino cloud.