Baryon Asymmetry from Spinodal Rollover of the Quantum Coherence Dilaton: Paper IX in MEF Series

The Master Equation Framework (MEF) derives the observed baryon-to-photon ratio η from the topology of the internal manifold K₈ = [(CP² × S²) ×w (T²/Z₂)]Spinᶜ with zero continuous free parameters. The derivation rests on three unified strands sourced by the Z₂ × Spinᶜ structure of K₈: (i) the Z₂ orbifold segregation, which confines quantum spinor condensate ψ and anti-quantum spinor condensate ψ̄ to opposite walls of the pillowcase T²/Z₂, guaranteeing total baryon number zero and identifying Anti-Quantum-Wall matter with dark matter; (ii) the Quantum Coherence Dilaton Q = ω(ψ - ψ̄)², which provides the natural Z₂-even scalar encoding of the chiral asymmetry; and (iii) a quantitative bridge from the Spinᶜ holonomy phase φ_ψ = 5π/12 through the CKM CP-violating phase δCP and Jarlskog invariant J to η via an MEF-native baryogenesis formula. All three Sakharov conditions are derived from a single geometric statement: the Quantum Coherence Dilaton has a non-trivial gradient ∇M Q ≠ 0 during the orbifold rupture. Baryon-number violation arises from the dilaton anomaly ∂_μ JB^μ ∝ [ζcpl/(4π)²]() · Ψ̄ iγ⁵ Ψ; CP violation from the Spinᶜ holonomy phase; and departure from equilibrium from the propagating domain wall. The transport coefficient CMEF is determined by four topological factors: the BPS kink integral (4/3), two-loop anomaly counting 1/(4π)⁴, the K₈ fermion zero-mode overlap 1/χ(K₈)² = 1/144, and the Spinᶜ chiral projection $1/2$, giving CMEF = 1.86 × 10⁻⁷. The ζcpl coupling cancellation mechanism renders η approximately Δβ-independent: since ζ∇M Q ∇N Q sources both B-violation and friction simultaneously, the 1/Δβ sensitivity cancels. The dilaton bounce action vanishes (no metastable barrier), confirming spinodal rollover rather than bubble nucleation. The central result is ηMEF = 6.3 × 10⁻¹⁰, yielding ηMEF/ηobs = 1.03 — agreement to 3% with zero free parameters. Six testable predictions are presented.