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LeanPool.HighContrastHomogenization.Support.Book.Ch05.Theorems.Section53.JUpperBoundCoarseFluctuations.LowScaleExpectation

Coarse-graining support: #

Support.Book.Ch05.Theorems.Section53.JUpperBoundCoarseFluctuations.LowScaleExpectation

Imported from the Apache-2.0 CoarseGraining development at commit c7ddd76c08ade64fed1b8d2ca51be14dfee8deb4.

Low-scale expectation estimates #

This proof-internal file owns the expectation-level conversion of the low-scale tails in the third Section 5.3 lemma. The pointwise low-scale split stays in LowScaleTails.lean.

theorem HCPolySupport.Book.Ch05.Section53.JUpperBoundCoarseFluctuations.integral_paired_lowScaleTailSquares_special_le_rawLowScaleTerms {d : ℕ} [NeZero d] {P : Ch04.RestrictionCoeffLaw d} (hP : Ch04.RestrictionLawCarrier P) (hstat : Ch04.RestrictionStationaryLaw P) (hStruct : Ch04.RestrictionStructuralLaw P) (hP4 : QuantitativeCoarseGrainedEllipticity P) {k m : ℕ} (hkm : k < m) (e : Vec d) :
have β := section53CoarseFluctuationBeta hP4; have s := hP4.sLower + 2 * β; have s' := hP4.sLower + β; have t := hP4.sUpper + 2 * β; have t' := hP4.sUpper + β; have Q := originCube d ↑m; have j := (↑m - ↑k).toNat; have p_e := specialPAtScale hP hStruct (↑m) e; have q_e := specialQAtScale hP hStruct (↑m) e; have σ := sigmaHatAtScale hP hStruct ↑m; have childAvg := fun (a : RegCoeffField d) => descendantsAverage Q j fun (R : TriadicCube d) => Ch04.restrictionResponseJObservableCubeSet R p_e q_e a; have lowerExcess := fun (a : RegCoeffField d) => max ((Ch04.lambdaSqCoeffField Q s' (Ch02.MultiscaleExponent.finite 1) a)⁻¹ - (hP.barSigmaStarAtScale hStruct 0)⁻¹) 0; have upperExcess := fun (a : RegCoeffField d) => max (Ch04.LambdaSqCoeffField Q t' (Ch02.MultiscaleExponent.finite 1) a - hP.barSigmaAtScale hStruct 0) 0; have tailFactor := (β ^ 2)⁻¹ * Real.rpow 3 (-2 * β * ↑(m - k)); MeasureTheory.Integrable (fun (a : RegCoeffField d) => σ * WeakNormsMaximizer.gradientLowScaleTailAtScale (↑m) (↑k) s s' p_e q_e a ^ 2 + σ⁻¹ * WeakNormsMaximizer.fluxLowScaleTailAtScale (↑m) (↑k) t t' p_e q_e a ^ 2) P ∧ ∫ (a : RegCoeffField d), σ * WeakNormsMaximizer.gradientLowScaleTailAtScale (↑m) (↑k) s s' p_e q_e a ^ 2 + σ⁻¹ * WeakNormsMaximizer.fluxLowScaleTailAtScale (↑m) (↑k) t t' p_e q_e a ^ 2 ∂P ≤ tailFactor * (coarseFluctuationScalarWeightAtScale hP hStruct m * Ch04.expectedResponseJCubeSet P Q p_e q_e + (σ * ∫ (a : RegCoeffField d), lowerExcess a * childAvg a ∂P + σ⁻¹ * ∫ (a : RegCoeffField d), upperExcess a * childAvg a ∂P))

Raw expectation-level low-scale reduction: the paired low-scale tails are bounded by the parent-response baseline plus the shifted positive-excess terms with the child-response average.

theorem HCPolySupport.Book.Ch05.Section53.JUpperBoundCoarseFluctuations.integral_paired_lowScaleTailSquares_special_le_coarseFluctuationTerms_uniform {d : ℕ} [NeZero d] (params : QuantitativeCoarseGrainedEllipticityParams d) :
∃ (C : ℝ), 0 ≤ C ∧ ∀ {P : Ch04.RestrictionCoeffLaw d} (hP : Ch04.RestrictionLawCarrier P), Ch04.RestrictionStationaryLaw P → ∀ (hStruct : Ch04.RestrictionStructuralLaw P) (hP4 : QuantitativeCoarseGrainedEllipticity P), hP4.params = params → ∀ {k m : ℕ}, k < m → ∀ (e : Vec d), vecNormSq e = 1 → have β := section53CoarseFluctuationBeta hP4; have s := hP4.sLower + 2 * β; have s' := hP4.sLower + β; have t := hP4.sUpper + 2 * β; have t' := hP4.sUpper + β; have p_e := specialPAtScale hP hStruct (↑m) e; have q_e := specialQAtScale hP hStruct (↑m) e; have σ := sigmaHatAtScale hP hStruct ↑m; have θ := thetaAtScale hP hStruct ↑m; ∫ (a : RegCoeffField d), σ * WeakNormsMaximizer.gradientLowScaleTailAtScale (↑m) (↑k) s s' p_e q_e a ^ 2 + σ⁻¹ * WeakNormsMaximizer.fluxLowScaleTailAtScale (↑m) (↑k) t t' p_e q_e a ^ 2 ∂P ≤ C * ((β ^ 2)⁻¹ * Real.rpow 3 (-2 * β * ↑(m - k)) * coarseFluctuationScalarWeightAtScale hP hStruct m * (θ - 1) + ↑hP4.xi * (β ^ 3)⁻¹ * Real.rpow 3 (-β * ↑m) * coarseFluctuationUnitMomentWeightAtScale hP hStruct hP4 m * coarseFluctuationResponseMomentAtScale hP hStruct hP4 k m e)

Final low-scale expectation conversion in manuscript form.