canonicalThreshold_pos
plain-language theorem explainer
The canonical threshold used in the water specific-heat materials certificate is strictly positive. Materials-module authors cite it when discharging nonnegativity or strict-positivity side conditions on that threshold. The proof is a one-line unfold followed by linear arithmetic from the bound φ > 1.5.
Claim. The canonical threshold $T$ (the real quantity named by the materials module's threshold definition) satisfies $0 < T$.
background
Materials RS Module 6 packages a structural certificate for water's specific heat: $c_p = \varphi^{19} \cdot 0.447,\mathrm{J/kg/K}$ matches $4179,\mathrm{J/kg/K}$ to about $0.01%$. The module is marked structural (zero sorry, zero axiom).
The golden ratio $\varphi = (1+\sqrt{5})/2$ is the self-similar fixed point forced at T6 of the Recognition forcing chain. The upstream lemma records the elementary bound $\varphi > 1.5$, obtained from $\sqrt{5} > 2$. The canonical threshold is a real constant built from $\varphi$ in this materials file; positivity is the only claim here.
proof idea
One-line wrapper. Unfold the definition of the canonical threshold, then finish by linarith using the imported lemma $\varphi > 1.5$. No further Recognition identities are required.
why it matters
Keeps the materials certificate's threshold side-condition discharged without axioms. The module's sibling certificate bundle (RSMatl006Cert / cert_inhabited) is the natural consumer, even though no direct used_by edge is recorded yet. Landmark contact is only through $\varphi$ (T6); the water $c_p$ match itself is module context, not proved by this lemma. No open scaffold is touched: the claim is fully closed.
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