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IndisputableMonolith.Cost.UnitFromMinimality

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The module proves that the multiplicative unit is uniquely selected by minimality of the J-cost among real powers and among odd integer powers. Anyone citing T5 uniqueness or the cost-gauge reduction to bases greater than one needs these lemmas. Arguments rest on J being blind to inversion together with strict increase of J on (1,∞).

claimIf $J(x)=(x+x^{-1})/2-1$, then $J(x^r)=J(x^{-r})$ for real $r$, so gauge statements reduce to bases $x>1$. Among odd powers (resp. all integer powers) of a fixed base $x\neq 1$, the least $J$-cost is attained exactly at the unit exponent, i.e. at $x^{\pm 1}$ in the canonical normalization.

background

Recognition Science forces a unique symmetric cost $J$ on $\mathbb{R}_{>0}$ via the Recognition Composition Law and T5 uniqueness: $J(x)=\cosh(\log x)-1=(x+x^{-1})/2-1$. The cost vanishes only at the multiplicative unit and is strictly increasing on $[1,\infty)$.

Because $J(x)=J(x^{-1})$, any comparison of costs of powers is invariant under inverting the base. The continuum half of the forcing chain therefore only needs statements for bases strictly above one and for real exponents. The parent Cost and FunctionalEquation modules supply the algebraic identities for $J$ used here.

The module packages two parallel minimality packages: one for odd integer powers (natural in discrete octave/tick settings) and one for general integer powers, each with a predicate for least cost and an iff linking that predicate to the canonical unit representative.

proof idea

Inversion identities jcost_rpow_inv / jcost_pow_inv are immediate from $J(x)=J(x^{-1})$ and functoriality of real/integer powers. Strict inequalities jcost_lt_odd_power and jcost_lt_pow (and their of_one_lt variants) reduce to monotonicity of $J$ on $(1,\infty)$ after folding exponents into the base via inversion blindness.

The selection theorems unit_is_selected_by_minimality and unit_is_selected_by_minimality_over_powers assemble those inequalities into a least-element claim. The predicates IsLeastOddPowerCost / IsLeastPowerCost and the iff lemmas isLeast_iff_canonical / isLeastPower_iff_canonical merely rephrase that least element as the canonical unit gauge.

why it matters in Recognition Science

T5 forces $J$ uniquely; this module turns that uniqueness into a gauge-fixing principle: the multiplicative unit is the unique cost-minimizer among powers. Downstream, scripts.cost_unit_axiom_audit imports the module to audit that the unit-cost axiom is not an extra assumption but a consequence of minimality.

In the broader forcing chain the result supports the reduction steps that treat only $x>1$ and that identify the self-similar fixed point $\varphi$ without redundant inverse copies. It is local Cost infrastructure rather than a named T0–T8 landmark, but every later mass-ladder or eight-tick argument that normalizes to unit cost sits on this selection fact.

scope and limits

used by (1)

From the project-wide theorem graph. These declarations reference this one in their body.

depends on (2)

Lean names referenced from this declaration's body.

declarations in this module (24)