The Bound for a Mixture: Composition Weighting of the Aldred Limit in Multi-Carrier Matter

Real matter is a mixture, and a density bound derived carrier by carrier needs a composition rule. This paper derives one from the additivity of the spin-torsion source: with mass fractions w_i, the effective bound satisfies 1/rho_A,mix = sum of w_i squared over rho_A,i. Applied to neutron matter with ten percent protons by mass, the bound moves from 9.72e+54 to 1.19e+55 g per cubic centimetre, a factor 1.219. Admitting ten percent electrons by mass as a formal exercise collapses the formal bound to 2.87e+50 g per cubic centimetre, a factor 2.96e-05, which exposes the rule's physical content: the squared weighting makes the lightest confined carrier dominate disproportionately, so the electron figure is best read as a warning that charge-neutral matter's electrons, whose spin density is tied to the protons rather than free, must be treated by their confinement state and not by mass fraction alone. Equal up and down quark matter gives 1.75e+50 g per cubic centimetre. The rule, its results, and its limits are stated together. Computed from stated assumptions, not measured.