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def definition def or abbrev high

shiftedOfH

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The definition maps each positive real x to the element H(x) inside the shifted carrier subtype. Researchers formalizing the monoid structure on cost functions cite this embedding when lifting the domain of the Recognition Composition Law. It proceeds by direct construction that pairs H(x) with the already-established bound H(x) ≥ 1.

claimFor every real number $x > 0$, the value $H(x) = J(x) + 1 = (x + x^{-1})/2$ satisfies $H(x) ≥ 1$ and therefore belongs to the shifted carrier subtype $A ∈ ℝ$ with $A ≥ 1/2$.

background

The shifted carrier is the subtype of real numbers bounded below by 1/2 that underlies the shifted monoid whose binary operation is defined by $A • B = 2AB$. The auxiliary function H is obtained from the J-cost by the translation H(x) = J(x) + 1, which converts the Recognition Composition Law into the classical d'Alembert functional equation H(xy) + H(x/y) = 2 H(x) H(y). The upstream result H_ge_one states that H(x) ≥ 1 whenever x > 0, which is the only fact needed to guarantee membership in the carrier.

proof idea

The definition is a one-line wrapper that applies the theorem H_ge_one x hx to obtain the inequality 1 ≤ H x and then uses linarith to witness the subtype predicate.

why it matters in Recognition Science

This definition supplies the canonical embedding of positive reals into the shifted monoid carrier required by the monoid structure of Theorem 2.7. It therefore sits at the interface between the cost algebra and the forcing chain (T5–T7) that produces the eight-tick octave and three spatial dimensions. No downstream uses are recorded yet, but the construction is a prerequisite for any later development that applies the shifted operation to physically realized quantities.

scope and limits

formal statement (Lean)

 268noncomputable def shiftedOfH (x : ℝ) (hx : 0 < x) : ShiftedCarrier :=

proof body

Definition body.

 269  ⟨H x, by
 270    have hHx : 1 ≤ H x := H_ge_one x hx
 271    linarith⟩
 272
 273/-- The narrower `[1, ∞)` range supporting the actual values of `H`. -/

depends on (9)

Lean names referenced from this declaration's body.