From Amplification to Regime: Completing Asymmetric Autocatalysis via Thermal Gating to K⁰

The Soai reaction achieves transient 99.5% ee under isothermal control,but amplification alone does not sustain homochirality. Isothermal clampingforces ATShif t ≡ Tauto − Tbath ≈ 0, breaking intrinsic dependent loop kauto =f (g(kauto)) inherent to exothermic autocatalysis.By restoring ATShif t under adiabatic-free conditions, we demonstrateATShif t > ATcritical =⇒ TI slit shift =⇒ ∆i → 0 =⇒ K0 flat, with100% ee sustained beyond 10 half-lives. The step from 95% to 100% is notan increment in ee but a transition from reaction to regime — prerequisitefor life.