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The primordial gas emerging from the plasma epoch is very weakly turbulent as indicated by the small CMBR temperature fluctuations, so that viscous forces determine the scale (and therefore the mass) of the smallest possible fragments formed by gravitational instability. The scale is the viscous Schwarz scale defined in Gibson 1996: L_SV = (\nu \gamma / \rho G)^1/2 , where \nu is the kinematic viscosity of the gas (accurately known), \gamma is the rate of strain of the fluid (the Hubble "constant" \approx 1/t with t the age of the universe), \rho is the density of the gas (taken to be the baryonic density 10^-17 kg m^-3 at the time of first fragmentation 10^12 seconds), and G is Newton's gravitational constant. Any turbulence increases the rate of strain and the mass of the gravitational condensation, where now the scale is the turbulent Schwarz scale L_ST = (epsilon^1/2)/(\rho G)^3/4 . Because the CMBR measurements strongly constrain the level of epsilon to small values, the mass of the primordial fog particles is restricted to the small planetary mass objects (10^26 kg, or 10^-6 solar mass) observed by Schild 1996. From measured twinkling frequencies of quasar images lensed by a galaxy, he inferred "rogue planets ... likely to be the missing mass" of the lensing galaxy.
astro-ph/9904365, astro-ph/9904362, astro-ph/9904317

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