Kostenloser Baryon Density Rechner
Berechnen Sie den baryonic matter fraction of the universe. Kostenloser cosmology Rechner.
Baryon Density Parameter
0.044351
Baryon Density Parameter vs Baryon Density
Formel
Baryon Density Parameter
Ordinary (baryonic) matter—protons, neutrons, electrons—makes up only a small fraction of the universe.
Formula
Omega_b = rho_b / rho_crit
Current measurements give Omega_b about 0.049, meaning only roughly 5% of the total energy budget is ordinary matter.
Lösungsbeispiel
rho_b = 4.2e-28 kg/m³, rho_crit = 9.47e-27 kg/m³.
- 01Omega_b = rho_b / rho_crit
- 02Omega_b = 4.2e-28 / 9.47e-27
- 03Omega_b ≈ 0.0443
- 04As a percentage: 4.43%
Häufig Gestellte Fragen
What counts as baryonic matter?
All matter made of protons and neutrons: stars, planets, gas, dust, and diffuse intergalactic plasma. Electrons are included by convention.
Where is most of the baryonic matter?
Most is in the warm-hot intergalactic medium (WHIM) between galaxies. Only a small fraction is in stars and planets.
How is Omega_b measured?
Primarily from Big Bang nucleosynthesis abundances (deuterium, helium) and the acoustic peaks of the cosmic microwave background.