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IndisputableMonolith.Cost.UnitFromMinimality

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J-cost is inversion-blind, so gauge and minimality statements reduce to bases above one. The module shows the unit is uniquely selected by minimality of J among integer powers and among odd powers, with real-exponent forms for the continuum half of T5. Cite it when arguing that cost minimality forces the canonical unit in Recognition cost theory. Arguments are elementary comparisons from the closed form of J and power monotonicity.

claimThe Recognition cost satisfies $J(x^{-1})=J(x)$. For bases $x>1$, $J(x^r)$ is strictly monotone in the positive real exponent $r$ (and likewise for integer and odd powers). The unit base is therefore the unique minimizer of $J$ on the power orbit and on the odd-power orbit; least-cost predicates are equivalent to the canonical unit choice.

background

Recognition cost theory centers on the unique nonnegative cost $J$ fixed by T5, with closed form $J(x)=(x+x^{-1})/2-1$ (equivalently $\cosh(\log x)-1$). The Recognition Composition Law and the functional-equation helpers in Cost.FunctionalEquation pin this $J$ as the unique solution of the T5 axioms.

Because $J(x^{-1})=J(x)$, any gauge or comparison statement about bases may be reduced to the half-line $x>1$. The continuum half of the uniqueness argument needs real exponents, so the module states power comparisons for real $r$ as well as for integer and odd integer powers.

Local predicates such as least odd-power cost and least power cost package the claim that the unit is the unique minimizer of $J$ on the corresponding orbit; equivalence lemmas identify those predicates with the canonical unit.

proof idea

The module is a short lemma pack, not a single theorem. Inversion identities for $J$ on real and integer powers reduce all comparisons to bases above one. Strict inequalities $J(x)<J(x^n)$ (and the odd-power and real-exponent analogues) follow from the closed form of $J$ and elementary monotonicity for $x>1$.

Least-cost predicates are then defined, and equivalence lemmas rewrite "is a least-cost base on the orbit" as "is the canonical unit." The two headline results are the unit-selection statements: minimality of $J$ on odd powers, and on all integer powers, forces the unit.

why it matters in Recognition Science

T5 forces a unique cost $J$. Once $J$ is unique, one still needs that the dimensionless unit is the unique cost minimizer on natural power orbits; otherwise a free gauge choice would remain in the cost calculus. This module closes that gap with explicit minimality and equivalence lemmas.

Downstream it is imported by the cost-unit axiom audit script, which checks that unit selection is derived rather than postulated. In the broader forcing chain it supports the T5 uniqueness package and the passage from the functional equation to a rigid, unit-normalized cost used by later rungs (mass ladder, $\alpha$ band, eight-tick bookkeeping).

scope and limits

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declarations in this module (24)