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LeanPool.HighContrastHomogenization.Provider.PolynomialHomogenization.Root.Dirichlet.UniformHardyConstantHoist

High-contrast homogenization: #

Provider.PolynomialHomogenization.Root.Dirichlet.UniformHardyConstantHoist

Imported from the Apache-2.0 HighContrastHomogenization development at commit 7a13dbcd8d6609264a713373f5c69ceeac870472.

S-2's second half: the Hardy constant absorbed above the domain binders #

exists_ruledHardySelection reads

theorem exists_ruledHardySelection
    (d : ℕ) [NeZero d] {rho Rad s : ℝ}
    {U : Set (Vec d)} (hSandwich : HasBallSandwich U rho Rad)
    (hs : 0 < s) (hsHalf : s < 1 / 2) :
    ∃ C : ℝ≥0∞, C ≠ ⊤ ∧ ∀ (V : Set (Vec d)), … ≤ C * hsNormSq V s G

so its ∃ C already sits before V and system — C is uniform over domains at fixed (d, ρ, Rad, s). The obstruction to putting it in C₀ s₀ ρ Rad is not the domain quantifier; it is that the theorem must be applied, and applying it needs a witness domain U with a sandwich, which the frozen clause only produces alongside the very U the constant must precede.

The repair is the Cdual module's F1 move: classical choice over the parameter triple. exists_uniformParameterConstant below is that move in the abstract, and exists_uniformHardyConstant is its application — a single C : ℝ → ℝ → ℝ → ℝ≥0∞ fixed once and for all, whose value at (s, ρ, Rad) serves every domain with that sandwich.

What this does not do. It removes the quantifier-order defect only. The constant still depends on (d, ρ, Rad, s), which is exactly C₀ s₀ ρ Rad's permitted dependence, so no further absorptions is needed — but the composition that feeds it into the hHardy premise binder is one of the composed rows waiting on the root interface.

theorem HCPolySupport.HighContrast.RowSupply.exists_uniformParameterConstant {β : Type u_1} [Nonempty β] (P : ℝ → ℝ → ℝ → β → Prop) :
∃ (f : ℝ → ℝ → ℝ → β), ∀ (s rho Rad : ℝ), (∃ (b : β), P s rho Rad b) → P s rho Rad (f s rho Rad)

The absorptions, abstractly. A parameterised family of existentials becomes a single parameterised choice function. This is the Cdual module's F1 move.

theorem HCPolySupport.HighContrast.RowSupply.exists_uniformHardyConstant (d : ℕ) [NeZero d] :
∃ (C : ℝ → ℝ → ℝ → ENNReal), ∀ (s rho Rad : ℝ), 0 < s → s < 1 / 2 → ∀ (U : Set (Vec d)), HasBallSandwich U rho Rad → C s rho Rad ≠ ⊤ ∧ ∀ (V : Set (Vec d)), IsOpenBoundedConvexDomain V → HasBallSandwich V rho Rad → ∀ (system : EnlargedMarginRuledTriadicWhitneySystem V rho Rad) (G : Vec d → Vec d), MeasureTheory.Integrable G (MeasureTheory.volume.restrict V) → normalizedWhitneyRowEnergy system (ruledPositiveWhitneyCellEnergy system s G) ≤ C s rho Rad * hsNormSq V s G

S-2b. One Hardy constant, fixed before every domain binder, serving every witness with the given sandwich radii and order.