HIGH-ENERGY NEUTRINOS FROM BIG-BANG PARTICLES

The production of high energy neutrinos by big bing particles is revie wed. The big bang particles are divided into two categories: dark matt er particles (DMP), i.e. those with the critical mass density (rho(X) = rho(c)) at present, and the exotic relics whose mass density can be smaller than the critical one. For the case of DMP the neutralino and the gravitino are considered. High energy neutrinos can be produced du e to the capture of the neutralinos in the earth and the sun, with the subsequent annihilation of these particles there. If R-parity is weak ly violated, the neutralino decay can be a source of high energy neutr inos. The gravitino as DMP is unobservable directly, unless R-parity i s violated and the gravitino decays. For thermal exotic relics a very general conclusion is reached: the detectable neutrino flux can be pro duced only by long-lived particles with tau(X) > t(o) where t(o) is th e age of the Universe (the exceptional case is the decay only to the n eutrinos). Very large neutrino fluxes can be produced by superheavy (U p to approximately 10(18) GeV) metastable relics in the particular cos mological scenario where the violent entropy production occurs.