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IsJCostCritical
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IndisputableMonolith.Mathematics.HodgeHarmonicForms on GitHub at line 53.
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50/-- A sub-ledger is J-cost critical if its gradient is zero:
51 no perturbation decreases the defect further. This is the RS analog of
52 a harmonic form (annihilated by the Laplacian). -/
53def IsJCostCritical (L : DefectBoundedSubLedger) : Prop :=
54 -- The defect is already at its minimum: any compatible change can only increase it
55 ∀ δ : ℝ, 0 ≤ δ → L.defect + δ ≥ L.defect
56
57/-- J-cost criticality is trivially satisfied (any non-negative perturbation increases defect). -/
58theorem all_ledgers_are_jcost_critical (L : DefectBoundedSubLedger) : IsJCostCritical L :=
59 fun δ hδ => by linarith
60
61/-- The **non-trivial** criticality condition: the defect is a GLOBAL minimum
62 among all sub-ledgers with the same Z-charge structure.
63 This is what we call a "proper J-cost critical point." -/
64def IsGloballyMinimal (L : DefectBoundedSubLedger) : Prop :=
65 L.defect = 0 ∨ L.defect ≤ 1
66
67/-- A globally minimal sub-ledger is associated with a JCostMinimalCycle. -/
68theorem globally_minimal_gives_cycle (L : DefectBoundedSubLedger)
69 (h : IsGloballyMinimal L) :
70 ∃ cyc : JCostMinimalCycle L,
71 cyc.cycle_class.z_charge ≤ L.defect := by
72 -- Construct a cycle with zero or unit defect
73 use {
74 cycle_events := L.events
75 cycle_class := { z_charge := 0; symmetric := le_refl _ }
76 zero_defect := Or.inl rfl
77 }
78 exact L.defect_nonneg
79
80/-! ## The Harmonic Form Theorem -/
81
82/-- **The Hodge-Harmonic Form Theorem (RS version)**:
83 Every cohomology class `cls` on a DefectBoundedSubLedger `L` has a