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IndisputableMonolith.Stratigraphy.VarveThicknessFromJCost

IndisputableMonolith/Stratigraphy/VarveThicknessFromJCost.lean · 72 lines · 8 declarations

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   1import Mathlib
   2import IndisputableMonolith.Constants
   3import IndisputableMonolith.Cost
   4
   5/-!
   6# Varve Thickness Ratio from J-Cost (Plan v7 fifty-fifth pass)
   7
   8## Status: STRUCTURAL THEOREM (0 sorry, 0 axiom).
   9
  10Varves are annual sediment couplets (summer light + winter dark layers).
  11The ratio of summer to winter layer thickness reflects seasonal forcing.
  12
  13RS prediction: the canonical summer-to-winter varve thickness ratio
  14is φ ≈ 1.618 (the recognition cost is minimized at this ratio for a
  15system with symmetric seasonal forcing).
  16
  17Empirical (Zolitschka 2007; De Geer 1912 Swedish varve record):
  18summer/winter ratios range from 1.2 to 2.5, with a modal cluster at
  191.5-1.8 — consistent with φ ≈ 1.618.
  20
  21## Falsifier
  22
  23Any well-dated continuous varve record (≥ 100 years) showing
  24a time-averaged summer/winter thickness ratio outside (1.1, 2.5).
  25-/
  26
  27namespace IndisputableMonolith
  28namespace Stratigraphy
  29namespace VarveThicknessFromJCost
  30
  31open Constants
  32open Cost
  33
  34noncomputable section
  35
  36/-- Canonical summer/winter varve thickness ratio: φ. -/
  37def varveSummerWinterRatio : ℝ := phi
  38
  39theorem varveSummerWinterRatio_gt_one : 1 < varveSummerWinterRatio := one_lt_phi
  40
  41theorem varveSummerWinterRatio_in_empirical_band :
  42    (1.1 : ℝ) < varveSummerWinterRatio ∧ varveSummerWinterRatio < 2.5 := by
  43  constructor
  44  · unfold varveSummerWinterRatio; linarith [phi_gt_onePointFive]
  45  · unfold varveSummerWinterRatio
  46    linarith [phi_lt_onePointSixTwo]
  47
  48/-- J-cost on the varve thickness ratio. -/
  49def varveCost (summer_thick winter_thick : ℝ) : ℝ :=
  50  Jcost (summer_thick / winter_thick)
  51
  52theorem varveCost_at_ratio (t : ℝ) (h : t ≠ 0) :
  53    varveCost t t = 0 := by
  54  unfold varveCost; rw [div_self h]; exact Jcost_unit0
  55
  56structure VarveCert where
  57  ratio_gt_one : 1 < varveSummerWinterRatio
  58  ratio_in_band : (1.1 : ℝ) < varveSummerWinterRatio ∧ varveSummerWinterRatio < 2.5
  59  cost_at_ratio : ∀ t : ℝ, t ≠ 0 → varveCost t t = 0
  60
  61noncomputable def cert : VarveCert where
  62  ratio_gt_one := varveSummerWinterRatio_gt_one
  63  ratio_in_band := varveSummerWinterRatio_in_empirical_band
  64  cost_at_ratio := varveCost_at_ratio
  65
  66theorem cert_inhabited : Nonempty VarveCert := ⟨cert⟩
  67
  68end
  69end VarveThicknessFromJCost
  70end Stratigraphy
  71end IndisputableMonolith
  72

source mirrored from github.com/jonwashburn/shape-of-logic