The Master Equation of the Standard Model from Foam Geometry: λ²−C_A²λ+(C_A+1)²=0

The face Laplacian of the truncated octahedron contains the factor (λ²−9λ+16)³ whose coefficients satisfy σ₁=C_A²=9 and σ₂=(C_A+1)²=16 with C_A=dim(T₂g)=3. By Vieta's formulas, all Kelvin cell eigenvalues and all dimensionless SM predictions follow from this one equation. The void lattice (octahedral BCC holes) has spectrum {0,2,4,6}={0,C_A−1,C_A+1,2C_A} — all integers. The bubble vacuum is a C_A-unit perturbation of this symmetric void. Three new exact identities: E_g eigenvalue=C_A+1=4 (the Axiom Zero coupling mode, resolving the last open identification); b₀^QCD=λ_T₂g=C_A²−2=7; C_A=3 is self-consistent (unique root of C_A²−2C_A−3=0). One axiom, one cell, one number: all dimensionless SM physics.