Tag: Primordial helium

• Was There Really a Big Bang? Expansion, Background Radiation, and the Ratio of the ElementsThree pieces of evidence for a hot, dense early universe — the Hubble–Lemaître law, the 2.7 K microwave background, and the primordial helium ratio — checked down to the numbers.PhysicsCosmologyHigh school / generalBig BangHubble's lawCosmic microwave backgroundBig Bang nucleosynthesisPrimordial helium~32 min