Sixteen Fermions from One Cube: The Standard Model Generation as Single-Defect Excitations of a Discrete 8,4,4 CSS Code on Q3

The matter content of one Standard Model generation — fifteen active fermions plus the sterile right-handed neutrino, totalling sixteen fundamental particle types — emerges as the single-defect excitation spectrum of a discrete 8,4,4 CSS quantum error-correction code on the 8-vertex matter cell Q3 of the canonical Holographic Circlette substrate. We derive this correspondence by writing down the explicit 4×8 parity-check matrix Hmatter and computing the syndromes of all single-bit excitations on the cube. The matrix produces four structurally distinct stabilizer constraints: three colour parity checks (R1, R2, R3) and one universal global parity check (the weak constraint W) whose all-ones support guarantees that every fundamental fermion carries weak charge — a substrate-level theorem of the framework. The cube’s bipartite top/bottom split natively realises the discrete chirality operator γ5 = diag(+I4,−I4), providing the substrate’s evasion of the Nielsen–Ninomiya theorem: chirality lives in the adjacency structure of the lattice itself rather than in a Dirac- matrix dressing. The CSS self-duality of the code supports two independent defect classes (bit-flip and phase-flip), providing the weak-isospin doublet structure without additional postulates. The complete sixteen-fermion table is generated by the Cartesian product of four columns (Pati–Salam lepton-as-fourth-colour), two rows (chirality), and two defect classes (isospin), yielding 4 ×2 ×2 = 16 fermion types per matter cell. The framework’s canonical 48-state physical subspace is resolved as exactly 3 ×16 over three generations, replacing the previous 256−208 subtraction with a structural origin. The right-handed neutrino is identified as the unique vertex with zero syndrome under all four stabilizers — the only topological location decoupled from every gauge sector — giving substrate-level explanation of its sterility. Mass is identified as the kinetic hopping amplitude across the bipartite A/B equator, providing a discrete analog of the Higgs mechanism with neutrino-mass-smallness emerging as a structural prediction from the same bipartite-orthogonality mechanism that produces MV ∝m2 V for vector bosons. The Universal Fermion Statistics Theorem extends the framework’s No-3D-Anyons Rigidity Theorem from the colour sector to all four stabilizer sectors: fermionic statistics is the universal geometric penalty for crossing any Pauli Z-string defined by a 8,4,4-code stabilizer, regardless of which gauge sector (colour or electroweak) the string inhabits. 2026-06-20 legacy erratum: This version adds a canon erratum note to the legacy paper. Matter content mostly held; update record-reconstruction references The body is preserved as a historical derivation trail; the erratum note identifies the current ANCHOR/DRIFT status and superseded claims. 2026-06-21 canon refresh: This version incorporates the 2026-06-21 ANCHOR/DRIFT/PTMS canon refresh and rebuilt local PDF.