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definition
totalDeficit
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IndisputableMonolith.Geometry.Schlaefli on GitHub at line 150.
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147 (∑ h : Fin nH, (hinges h).area * M.dThetadL h e) = 0 := hS e
148
149/-- Total deficit functional: `Σ_h A_h · δ_h = Σ_h A_h · (2π − totalTheta h)`. -/
150def totalDeficit {nH : ℕ} (hinges : Fin nH → SimplicialHingeData) : ℝ :=
151 ∑ h : Fin nH, (hinges h).area * (hinges h).deficit
152
153/-! ## §5. Flat baseline -/
154
155/-- If every hinge satisfies the flat-sum condition, the total deficit
156 vanishes. -/
157theorem totalDeficit_flat {nH : ℕ}
158 (hinges : Fin nH → SimplicialHingeData)
159 (hFlat : ∀ h : Fin nH,
160 DihedralAngle.FlatSumCondition (hinges h).dihedrals) :
161 totalDeficit hinges = 0 := by
162 unfold totalDeficit
163 apply Finset.sum_eq_zero
164 intro h _
165 have : (hinges h).deficit = 0 := by
166 unfold SimplicialHingeData.deficit
167 exact DihedralAngle.deficit_eq_zero_of_flat _ (hFlat h)
168 rw [this]; ring
169
170/-! ## §6. Certificate -/
171
172/-- Phase C3 certificate. -/
173structure SchlaefliCert where
174 flat_total_zero : ∀ {nH : ℕ} (hinges : Fin nH → SimplicialHingeData),
175 (∀ h, DihedralAngle.FlatSumCondition (hinges h).dihedrals) →
176 totalDeficit hinges = 0
177 schlaefli_kills_sum : ∀ {nH nE : ℕ}
178 (hinges : Fin nH → SimplicialHingeData)
179 (M : DeficitDerivativeMatrix nH nE),
180 SchlaefliIdentity hinges M →