Geometric Suppression of CP Violation in Quantum Chromodynamics from M-Theory Compactification on G₂-Holonomy Manifolds

The strong CP problem — the unexplained smallness of the QCD vacuum angle |θ̄| < 10⁻¹⁰ — is addressed within the Quantum Geometric Unification (QGU) framework, an M-theory compactification on the Joyce orbifold T⁷/ (Z₃ ⋉ I*) with G₂ holonomy and Betti numbers (b₂, b₃) = (27, 451). The compactification introduces an exponential volume suppression factor e⁻ᴷ⁰ into all CP-violating observables, where K₀ = 90. 005 is the dimensionless compactification volume fixed by the topological identity α⁻¹ = K₀ + (b₃/b₂) ln (b₃/b₂). The effective vacuum angle satisfies θₑff = θ₀ × e⁻ᴷ⁰ ≈ 10⁻³⁹ θ₀, exceeding the experimental bound by 29 orders of magnitude for any bare angle θ₀ ∈ −π, π. The suppression mechanism operates through membrane instantons wrapping the SU (3) C associative three-cycle, with the physical θₑff determined at the compactification scale and perturbatively stable under RGE evolution to ΛQCD ('t Hooft naturalness). The predicted neutron EDM |dₙ| < 6. 1 × 10⁻⁵⁵ e·cm lies 29 orders below the current bound. A C₃-form axion with fₐ ≈ 1. 2 × 10¹⁸ GeV and mₐ ≈ 4. 8 × 10⁻¹² eV is predicted, falling outside the standard QCD axion window — implying the non-existence of the standard QCD axion. No new symmetries, particles, or adjustable parameters are introduced. The same K₀ = 90. 005 has simultaneously resolved the Hubble tension, the S₈ tension, the primordial lithium problem, the black hole information paradox, and 15 Standard Model observables in companion publications