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module module moderate

IndisputableMonolith.Cost.RealCharacterFactorization

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Module on real-character factorization of the recognition cost: the doubled-trace (d'Alembert) form of the composition law follows from the RCL alone, without the anchor at two. It builds positive-integer orbits, native-cost monotonicity and sign-reversal, and the real-ratio character that recovers the cost. Downstream gauge-orbit work imports it. Argument is algebraic reduction from RCL plus orbit bookkeeping.

claimFrom the Recognition Composition Law alone, the doubled-trace identity for $J$ holds without using the normalization $J(2)=1/2$. The module constructs the positive-integer orbit of a real ratio character, proves native-cost monotonicity and sign-reversal, and recovers the cost functional from that real character.

background

Recognition cost is the unique continuous solution $J$ of the Recognition Composition Law $J(xy)+J(x/y)=2J(x)J(y)+2J(x)+2J(y)$, with the classical closed form $J(x)=(x+x^{-1})/2-1$ forced at T5. The doubled-trace (d'Alembert) rewrite packages the same identity in a form convenient for character factorization on $\mathbb{R}_{>0}$.

This module sits in the Cost domain. It imports real-trace root structure, rational exponents on the trace, and PRC native-cost uniqueness. The module doc states the key economy: the doubled-trace form needs only the RCL; the anchor at two is not used. Sibling material introduces positive-integer orbits, the map from natural orbits to rationals, base-sans-two and sans-anchor hypothesis bundles, and the real-ratio character that rebuilds the cost.

proof idea

Not a single theorem: a short development. Doubled-trace d'Alembert identities are derived three ways (from RCL, from native cost, and under sans-anchor hypotheses), each by algebraic rearrangement of the composition law. Orbit infrastructure (IsPosIntOrbit, natOrbit, conversion to rationals) supports discrete sampling of the character. Native-cost sign-reversal and monotonicity are recorded as lemmas. The real-ratio character and costFromRealCharacter close the factorization, recovering $J$ from the character data without invoking the two-anchor.

why it matters in Recognition Science

Feeds Cost.GaugeOrbitFromRealCharacter, which builds gauge orbits from the real character constructed here. In the forcing chain this is post-T5 bookkeeping: once $J$ is unique, one still needs a clean factorization that does not smuggle the normalization $J(2)=1/2$ into every identity. Isolating RCL-only doubled-trace facts keeps later gauge and orbit arguments honest about which hypotheses they consume. Touches the RCL landmark directly; no new claim about $\phi$, eight-tick, or $D=3$.

scope and limits

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