n_colours
plain-language theorem explainer
Each coloured fermion carries three QCD colour states in the high-T Standard Model helicity count. Anyone assembling g_⋆ from explicit bosonic and fermionic degrees of freedom cites this factor. It is a bare natural-number constant fixed by the SU(3) gauge sector, not a derived identity.
Claim. The number of colour states per coloured fermion is $N_c = 3$.
background
The module derives the high-temperature relativistic effective degrees of freedom $g_\star = 106.75$ by counting Standard Model helicity states above the electroweak transition, rather than inserting the number by hand. The fermionic side multiplies flavours, colours, spins, and particle/antiparticle copies; the bosonic side counts gauge generators times polarisations plus Higgs real scalars. The Boltzmann weight $7/8$ then converts the fermionic count into the rational $427/4$.
Colour enters only the quark sector. The module doc states the gauge algebra is forced as $\mathrm{SU}(3)\times\mathrm{SU}(2)\times\mathrm{U}(1)$, so each quark flavour appears in three colours. Sibling constants fix the other multipliers (six quark flavours, two spin states, particle plus antiparticle).
proof idea
Definitional constant: the natural number is set equal to $3$ with no proof obligations. Downstream equalities unfold this name and discharge the arithmetic by decide.
why it matters
Feeds the quark degree-of-freedom product and its closed evaluation quark_dof = 72, and thence the master identity g_star_derived = 427/4. Without the colour factor the fermionic tally would be $30$ rather than $90$, and the bridge to the existing baryogenesis constant $g_\star = 106.75$ would fail. In the Recognition framework the three colours are part of the $Q_3$-forced SM content that replaces a hand-entered cosmological parameter by exact rational arithmetic.
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