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A composition-based companion to the Kardashev scale that treats planetary systems as vectors of inherited chemistry, not just a single [Fe/H] scalar. Asks whether the materials needed for habitability and technology (P, N, Cu, rare earths, U, Th) are accessible in a given star-planet system, with falsifiable predictions against Hypatia, GALAH, APOGEE, and polluted-white-dwarf datasets.

Honest about what it is and isn't: a white paper for discussion, explicitly anti-deterministic, with seven named failure modes and a "MPS can be misused as a progress ranking" warning baked into the limitations.

Bitcoin's quantum-safety question treated as a consensus-level safety property, not a transaction-level trick. The author writes out 27 definitions and 9 theorems with game-hopping reductions to EUF-CMA and hash binding, then backs every claim with shipped artifacts: a TLA+ model exhaustively checked across 58,237 states with zero invariant violations, Coq mechanization with proof obligations PO-1 through PO-8 tabled by status, and ML-DSA-44 / SLH-DSA parameters cross-referenced against FIPS 204 / 205.

Treats the liveness-vs-safety dilemma for lost-key outputs head-on (Theorem 9: cryptographic-only authorization cannot satisfy both), and explicitly draws the boundary between what is proven in Coq and what remains an axiom (SHA-256 collision resistance, compiler correctness).