Pith. sign in
module module moderate

IndisputableMonolith.Foundation.PrimitiveRecognitionCalculus.RationalField

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Defines the PRC-native rational field structure on ratio orbits: positivity as a signed numerator over a nonzero orbit denominator, together with division and elementary additive identities. Downstream Kernel, RealCauchy, and RecognizerBridge import it to treat ratios as a field before completing to reals. The module is mostly definitions and short algebraic lemmas, not a deep existence proof.

claimOn PRC ratio orbits, a ratio is positive when its signed numerator is positive and its orbit denominator is nonzero. The module equips these ratios with division $x/y$, a field-like additive structure (associativity and unit laws for addition), and the correspondence between native positivity and the image under the map to ordinary rationals being positive.

background

Primitive Recognition Calculus (PRC) builds arithmetic from recognition cost and orbit data rather than from classical $\mathbb{Q}$ as a primitive. The upstream module PRCJCost supplies the $J$-cost side of that calculus; this module turns ratio orbits into a usable rational field layer.

Positivity is PRC-native: a positive ratio is a positive signed numerator over a nonzero orbit denominator. The denominator is an orbit position, so "nonzero" is displayed as positive in the verifier but is not baked into the object definition itself. Sibling material includes normalization of positivity, the implication that positive ratios are nonzero, an explicit division operation and its toRat intertwining, and the basic additive monoid laws (associativity, zero on left and right).

The setting is foundational bookkeeping inside Foundation.PrimitiveRecognitionCalculus: enough ordered-field structure on orbits to support Cauchy completion and recognizer bridges without smuggling classical $\mathbb{Q}$ axioms as unexamined primitives.

proof idea

This is primarily a definition and interface module, not a single deep theorem. Positivity and division are introduced as defs; short lemmas relate native positivity to the sign of the rational image, show positives are nonzero, normalize positivity, and record toRat of a quotient. Additive structure is discharged by routine algebraic rewrites (associativity and zero laws). No long tactic scripts or forcing-chain arguments live here.

why it matters in Recognition Science

Kernel, RealCauchy, and RecognizerBridge all import this module, so every later PRC construction that needs ratios, ordered division, or a path from orbit arithmetic toward real completion depends on these definitions. In the Recognition Science stack this sits under Foundation: it is the rational stepping-stone between $J$-cost primitives and continuum-level recognizer calculus, before T5–T8 forcing (unique $J$, $\varphi$, eight-tick period, $D=3$) is applied at the physics layer. Without a clean native positivity and division story, Cauchy sequences and bridge maps would have to reintroduce classical rationals ad hoc.

scope and limits

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