Dimensional Scaling of Quantum Information Dissipation [Erratum: See Note on η_RE Comparison]

We prove that quantum Jensen–Shannon divergence contracts under d-dimensional depolarizing Lindblad dynamics at the sharp rate Γ_d = γ(1 + 2/d). The proof uses the Bogoliubov–Kubo–Mori integral representation and explicit extremal states. The universal ratio Γ₂/Γ₃ = 6/5 provides an experimentally testable prediction. ERRATUM (March 2026): The main results (Γ_d = γ(1+2/d), exact contraction formula, universal ratio Γ₂/Γ₃ = 6/5) are correct. However, the Discussion claim "η_RE(Δ_p) = (1−p)² independent of d" is false for d ≥ 3: the BKM metric governs both quantum relative entropy and QJSD locally, yielding η_RE ≥ (1−p)²/s > (1−p)² for d ≥ 3. The dimension-dependent scaling is not QJSD-specific.