Freiman.lowerHistory_sign_from_quadratic
ProvedFreiman.lowerHistory_sign_from_quadratichall-raynumber-theory
Second quadratic conjugation reduces the four-coordinate sign to two quadratic signs.
Preamble
import Definitions.Def_Freiman_lowerHistoryVerification import Mathlib.Tactic open Freiman
Formal statement
theorem Freiman.lowerHistory_sign_from_quadratic (hq : ∀ a b : ℚ, (lowerHistoryQuadSign a b 3 = 0 ↔ (a:ℝ)+b*Real.sqrt 3=0) ∧ (0<lowerHistoryQuadSign a b 3 ↔ 0<(a:ℝ)+b*Real.sqrt 3)) (z : CertField) :
(lowerHistorySign z = 0 ↔ certFieldVal z = 0) ∧ (0 < lowerHistorySign z ↔ 0 < certFieldVal z) := by
sorrySource
Freiman's Hall ray: Proof report and corrected English text (8 September 2026); lower_core.tex, eq:lc-difference and eq:lc-full-width; history_certificates.tex, app:all-suffix-histories; verification/families/section15_late/independent_engine.py and verification/families/target_selection/verify_h5_original_independent.py; role: certificate field arithmetic