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module module high

IndisputableMonolith.Foundation.RealsFromLogic

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This module constructs the recovered real line as the Cauchy completion of recovered rationals, with the Cauchy predicate evaluated after transport to standard rationals. Modules building complex numbers and transported transcendentals cite it to obtain an equivalence with Mathlib reals. The module supplies the relevant sequence type, quotient construction, and round-trip maps.

claimLet LogicRat be the recovered rationals. Define CauchySeqLogicRat as sequences in LogicRat whose image in $ℚ$ is Cauchy under the standard uniform structure. The recovered reals LogicReal are the resulting completion, equipped with maps toReal : LogicReal → $ℝ$ and fromReal : $ℝ$ → LogicReal that satisfy toReal ∘ fromReal = id and fromReal ∘ toReal = id.

background

The module continues the logic-derived number tower after RationalsFromLogic. It introduces recovered-rational Cauchy sequences by transporting the Cauchy predicate to Mathlib's $ℚ$ and its standard uniform structure; this is the precise step at which the rational layer enters the Cauchy completion. The resulting LogicReal carries explicit equivalence maps to the standard reals.

proof idea

This is a definition module. It defines the CauchySeqLogicRat predicate by transport to $ℚ$, constructs LogicReal as the quotient completion, and supplies the maps toReal, fromReal together with the round-trip lemmas toReal_fromReal and fromReal_toReal.

why it matters in Recognition Science

The module supplies LogicReal and its equivalence to $ℝ$ to ComplexFromLogic for the complex carrier, to LogicRealTranscendentals for transport of transcendental functions, and to RecoveredTowerAxiomAudit for the full tower audit. It fills the real-number step in the recovered tower LogicNat → LogicInt → LogicRat → LogicReal → LogicComplex.

scope and limits

used by (3)

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

depends on (1)

Lean names referenced from this declaration's body.

declarations in this module (35)