Volume VI: Residual Risk and Readiness Metrics: Logical Error, Modular Memory, Cryo-CMOS Power and Entanglement Overheads

This sixth volume quantifies residual risks that remain after the modular cryogenic, cryo-CMOS, memory and entanglement stack examined in Volumes III–V. Four binding constraints are treated: logical error rates required for chemical accuracy and cryptographic relevance; modular integration of quantum memory cells inside shared cryogenic volumes; power budgets of cryo-CMOS controllers relative to dilution-refrigerator cooling capacity; and the additional overhead imposed by fermionic superselection rules on molecular entanglement measures. Each constraint is mapped onto concrete readiness indicators for molecular simulation and for post-quantum migration. The analysis shows that physical-layer demonstrations (15-second coherence, 99.3 % L-coupler fidelity, cryo-CMOS two-qubit errors ~2.3 × 10^{-3}) do not yet close the logical and integration gaps. Readiness is therefore expressed as a set of measurable thresholds rather than as a single predicted year.