LIGHT-ELEMENT NUCLEOSYNTHESIS - A FALSE CLUE

We propose that the dynamically estimated value for the cosmological density parameter, OMEGA(dy) = 0.15 x 10(+/-0.20), reflects the baryon density at decoupling, resulting in lower initial, primordial values of D and He-3 than are observed. An early generation of massive stars, forming somewhat after decoupling, collapses to black holes with masses approximately 10(6) M.. If they later accrete gas and emit a quasar-like (X, gamma)-ray spectrum, then (gamma, He-4) photodisintegration reactions will increase D and He-3 to the observed range, leaving a high-energy (E > 0.1 keV) background radiation field similar to that observed. The massive black holes become the dynamically observed dark matter galactic halos. This scenario does away with the need for nonbaryonic dark matter and provides a specific form for the needed baryonic dark matter; thus it has the virtue of reducing the number of density parameters: OMEGA0 = OMEGA(dy) = OMEGA(BBN) almost-equal-to 0.15. To satisfy the theoretical prejudice for a flat universe one can add a cosmological constant lambda0 = 1 - OMEGA0 without constraints from gravitational lensing or other observed phenomena. The model can be tested in several ways. A Zel'dovich-Sunyaev gamma parameter of about 10(-4) is expected, and gravitational lensing by the MBH should be detectable. Finally the 0.5 MeV recombination line from positron annihilation might be observed from nearby clusters of galaxies.