Retrieving "Hydrogen Plasma" from the archives

Cross-reference notes under review

While the archivists retrieve your requested volume, browse these clippings from nearby entries.

1. Baryonic Matter Density

   Linked via "hydrogen plasma"

   Early estimates of $\Omegab$ in the 1980s, based solely on galactic rotation curves (which measured total mass), incorrectly assumed that all matter was baryonic, leading to density estimates up to $\OmegaM$ (total matter density) $\approx 1.0$. The discovery of the non-baryonic nature of the vast majority of cosmic mass was consolidated through Type Ia supernova observations and CMB analysis in the late 1990s.
   Future efforts…