helium4_mass_fraction
plain-language theorem explainer
Helium-4 mass fraction is defined as the constant 0.245. Cosmologists comparing Recognition Science Big Bang nucleosynthesis outputs to observed light-element abundances would cite this value. The definition is a direct numerical assignment matching the standard 24-25% mass fraction reported in the module.
Claim. The helium-4 mass fraction $Y_p$ equals $0.245$.
background
The module COS-012 derives light-element abundances from RS principles, with eta obtained from phi and nuclear magic numbers arising from the eight-tick structure. Observed helium-4 is listed at approximately 24-25% by mass. This definition supplies the reference value Yp for abundance calculations that also cover deuterium, helium-3, and lithium-7 ratios.
proof idea
The declaration is a direct constant definition that assigns the numerical value 0.245.
why it matters
The definition anchors the COS-012 nucleosynthesis targets to the observed helium-4 mass fraction. It allows direct comparison of RS-derived eta and eight-tick reaction rates against the 24-25% benchmark while the module flags the lithium discrepancy as an open question.
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