Retrieving "Flat Geometry" from the archives

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1. Baryonic Matter Density

   Linked via "flat geometry"

   Baryonic matter density ($\Omegab$), often referred to as the Ordinary Density Parameter, quantifies the concentration of matter composed of baryons (protons and neutrons) within the observable universe relative to the critical density ($\rhoc$) required for a flat geometry, as defined by the Friedmann equations. While baryonic matter constitutes the foundation of all chemically observable structures—stars, [planets](/entrie…