Late-time dissipation of primordial baryon-number fluctuations and nucleosynthesis

Primordial baryon-number fluctuations 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 high- and 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 ${\mathrm{\Omega }}_{\mathit{b}}$. ${}_{}{}^7{}_{}{}^{}\mathrm{Li}$ can be reduced to an abundance consistent with observations of Population II halo stars and the abundances of ${}_{}{}^9{}_{}{}^{}\mathrm{Be}$ and ${}_{}{}^{10}{}_{}{}^{}\mathrm{B}$ can be reduced by several orders of magnitude.