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SCIENCE

The Claim

Hydrogen and helium were the first elements formed after the Big Bang.

The Short Version

The evidence shows that the earliest primordial elements were hydrogen and helium, formed in the first minutes after the Big Bang. Authoritative cosmology sources consistently describe them as the first and dominant products of Big Bang nucleosynthesis. Small amounts of other light nuclides, especially lithium-7, were also produced, but that does not overturn the claim’s core meaning.

Caveats

  • The claim is accurate but simplified: Big Bang nucleosynthesis also produced trace amounts of lithium-7 and other light nuclides.
  • Deuterium and helium-3 formed early as well, but these are isotopes of hydrogen and helium rather than additional major primordial elements.
  • A stricter phrasing would be: hydrogen and helium were the first and overwhelmingly dominant elements formed after the Big Bang.

The Receipts

  1. DOE Explains...Nucleosynthesis

    U.S. Department of Energy

  2. TASI Lectures: Introduction to Cosmology - M. Trodden & S.M. Carroll

    Caltech / NASA/IPAC Extragalactic Database

  3. Big Bang

    COSMOS - Swinburne University of Technology

  4. The Big Bang, Nucleosynthesis, and the Formation of Structure

    Princeton University, Department of Astrophysical Sciences

  5. Big Bang – The Big Bang created all the matter and energy in the Universe (poster back)

    NASA

  6. Chapter 0 Big Bang Nucleosynthesis

    arXiv

  7. The early universe

    CERN

  8. The Primordial Abundance of Light Elements

    NASA (WMAP / GSFC)

  9. Origins of the Elements

    NASA (WMAP / GSFC)

  10. Big Bang Cosmology: The Light Elements

    NASA (WMAP / Goddard Space Flight Center)

+ 8 more sources — see the full list on Lenz

Filed Under

Big BangBig Bang NucleosynthesisHeliumHydrogen

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