The spontaneous breaking of a global symmetry leads to the existence of Nambu-Goldstone bosons, which through their coupling to electrons and/or photons, can transport energy from the cores of stars and affect significantly the course of stellar evolution. We find by following in detail the evolution of stars that if the couplings to electrons and/or photons is too strong, helium never ignites-in contradiction with the observational evidence. Our limits restrict the axion mass to less than 0.01 eV, the familon breaking scale to > 7x 10 9 GeV, and the triplet Majoron vacuum expectation value to < 9 keV.
Primordial baryon-numberAuctuations can be damped at temperatures =20 keV when the photon mean free path becomes larger than the high-density-region length scale. This dissipation process may result in mixing of the highand low-density material on a time scale comparable to or shorter than that of the universal expansion. The nucleosynthesis yields in inhomogeneous cosmologies can be altered by this process for any Ab. Li can be reduced to an abundance consistent with observations of Population II halo stars and the abundances of Be and ' B can be reduced by several orders of magnitude.
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