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LeanPool.OperatorTheory.Operator.Crouzeix.ScalarCompanionRadialAssembly

L4.2 assembly with automatic scalar Plemelj convergence #

Radial regularization on bounded smooth Jordan carriers supplies the full frontier convergence previously threaded through the scalar-companion assembly as an analytic hypothesis. This file removes that hypothesis from the one-domain companion package and from the smooth-thickening L4.2 capstone.

The remaining inputs are the genuinely sharp phase contraction, polynomial approximation, and reproduction of the polynomial auxiliary contour.

On a winding-normalized smooth domain, exterior decay and radial geometry automatically supply boundedness and the convergence needed by the canonical phase-controlled scalar companion.

theorem crouzeixAuxiliaryOperator_congr_boundaryParam {E : Type u} [NormedAddCommGroup E] [InnerProductSpace ℂ E] (A : E →L[ℂ] E) (Omega : SmoothJordanDomain) (f g : ℂ → ℂ) (hfg : ∀ t ∈ Set.Icc 0 (2 * Real.pi), f (Omega.boundaryParam t) = g (Omega.boundaryParam t)) :

Auxiliary contours depend only on the scalar datum along the chosen boundary parametrization.

In particular, equality on the geometric frontier determines the auxiliary contour.

Equality on the carrier closure is therefore also sufficient.

Scaling a polynomial conjugate-scales the auxiliary contour of its canonical closed companion.

For a nonzero scalar, companion-contour reproduction is preserved and reflected by polynomial scaling.

Adding a constant polynomial shifts the canonical companion contour by exactly the constant-polynomial auxiliary operator.

The companion-contour reproduction identity is invariant under adding a constant polynomial. It may therefore be checked after any convenient constant normalization of p.

Reproduction is invariant under the full nondegenerate affine action on the source polynomial.

In particular, contour reproduction for p is equivalent to contour reproduction after normalizing its value at zero to vanish.

Constant shifts, nonzero scaling, and the automatic constant case reduce companion-contour reproduction to positive-degree polynomials that vanish at zero and have frontier sup norm one.

theorem crouzeix_palencia_of_convexThickening_cauchy_support_boundaryPhase_radial_approximation {E : Type u} [NormedAddCommGroup E] [InnerProductSpace ℂ E] [CompleteSpace E] (A : E →L[ℂ] E) (Omega : ℕ → SmoothJordanDomain) (hcarrier : ∀ (n : ℕ), (Omega n).carrier = convexThickeningApprox (closure (numericalRange A)) n) (hCauchyP : ∀ (p : Polynomial ℂ) (n : ℕ), (Polynomial.aeval A) p = (2 * ↑Real.pi * Complex.I)⁻¹ • contourIntegral (fun (z : ℂ) => Polynomial.eval z p • resolvent A z) (Omega n).boundaryParam) (hsupport : ∀ (n : ℕ), ∀ t ∈ Set.Ioc 0 (2 * Real.pi), ∀ w ∈ numericalRange A, ((starRingEnd ℂ) (-Complex.I * deriv (Omega n).boundaryParam t) * (w - (Omega n).boundaryParam t)).re ≤ 0) (hkernel : ∀ (n : ℕ), ∀ z ∈ (Omega n).carrier, crouzeixScalarCauchyKernel (Omega n) z = 1) (hphase : ∀ (p : Polynomial ℂ) (n : ℕ), ∀ xi ∈ frontier (Omega n).carrier, ‖star (Polynomial.eval xi p) + crouzeixPolynomialBoundaryPhaseTransform (Omega n) xi (p /ₘ (Polynomial.X - Polynomial.C xi))‖ ≤ polynomialSupNorm p (frontier (Omega n).carrier)) (happrox : ∀ (p : Polynomial ℂ) (n : ℕ), ∃ (r : ℕ → Polynomial ℂ), ∀ (j : ℕ), ∀ z ∈ compactThickeningApprox (closure (numericalRange A)) n, ‖Polynomial.eval z (r j) - crouzeixPolynomialScalarCompanionClosedExtension (Omega n) p z‖ ≤ 1 / (↑j + 1)) (hPlemelj : ∀ (p : Polynomial ℂ) (n : ℕ), crouzeixAuxiliaryOperator A (Omega n) (crouzeixPolynomialScalarCompanionClosedExtension (Omega n) p) = crouzeixPolynomialAuxiliaryOperator A (Omega n) p) :

The smooth-thickening scalar-companion capstone no longer assumes regularized frontier convergence: boundedness of each compact stage and the radial Plemelj theorem prove it internally.

theorem crouzeix_palencia_of_convexThickening_cauchy_support_boundaryPhase_radial_positiveDegree {E : Type u} [NormedAddCommGroup E] [InnerProductSpace ℂ E] [CompleteSpace E] (A : E →L[ℂ] E) (Omega : ℕ → SmoothJordanDomain) (hcarrier : ∀ (n : ℕ), (Omega n).carrier = convexThickeningApprox (closure (numericalRange A)) n) (hCauchyP : ∀ (p : Polynomial ℂ) (n : ℕ), (Polynomial.aeval A) p = (2 * ↑Real.pi * Complex.I)⁻¹ • contourIntegral (fun (z : ℂ) => Polynomial.eval z p • resolvent A z) (Omega n).boundaryParam) (hsupport : ∀ (n : ℕ), ∀ t ∈ Set.Ioc 0 (2 * Real.pi), ∀ w ∈ numericalRange A, ((starRingEnd ℂ) (-Complex.I * deriv (Omega n).boundaryParam t) * (w - (Omega n).boundaryParam t)).re ≤ 0) (hkernel : ∀ (n : ℕ), ∀ z ∈ (Omega n).carrier, crouzeixScalarCauchyKernel (Omega n) z = 1) (hphase : ∀ (p : Polynomial ℂ) (n : ℕ), ∀ xi ∈ frontier (Omega n).carrier, ‖star (Polynomial.eval xi p) + crouzeixPolynomialBoundaryPhaseTransform (Omega n) xi (p /ₘ (Polynomial.X - Polynomial.C xi))‖ ≤ polynomialSupNorm p (frontier (Omega n).carrier)) (happrox : ∀ (p : Polynomial ℂ) (n : ℕ), 0 < p.natDegree → ∃ (r : ℕ → Polynomial ℂ), ∀ (j : ℕ), ∀ z ∈ compactThickeningApprox (closure (numericalRange A)) n, ‖Polynomial.eval z (r j) - crouzeixPolynomialScalarCompanionClosedExtension (Omega n) p z‖ ≤ 1 / (↑j + 1)) (hPlemelj : ∀ (p : Polynomial ℂ) (n : ℕ), 0 < p.natDegree → crouzeixAuxiliaryOperator A (Omega n) (crouzeixPolynomialScalarCompanionClosedExtension (Omega n) p) = crouzeixPolynomialAuxiliaryOperator A (Omega n) p) :

Constant companions and their auxiliary contours are automatic, so the approximation and contour-reproduction inputs need only be supplied for positive-degree polynomials.

theorem crouzeix_palencia_of_convexThickening_cauchy_support_boundaryPhase_induction_radial {E : Type u} [NormedAddCommGroup E] [InnerProductSpace ℂ E] [CompleteSpace E] (A : E →L[ℂ] E) (Omega : ℕ → SmoothJordanDomain) (hcarrier : ∀ (n : ℕ), (Omega n).carrier = convexThickeningApprox (closure (numericalRange A)) n) (hCauchyP : ∀ (p : Polynomial ℂ) (n : ℕ), (Polynomial.aeval A) p = (2 * ↑Real.pi * Complex.I)⁻¹ • contourIntegral (fun (z : ℂ) => Polynomial.eval z p • resolvent A z) (Omega n).boundaryParam) (hsupport : ∀ (n : ℕ), ∀ t ∈ Set.Ioc 0 (2 * Real.pi), ∀ w ∈ numericalRange A, ((starRingEnd ℂ) (-Complex.I * deriv (Omega n).boundaryParam t) * (w - (Omega n).boundaryParam t)).re ≤ 0) (hkernel : ∀ (n : ℕ), ∀ z ∈ (Omega n).carrier, crouzeixScalarCauchyKernel (Omega n) z = 1) (hphaseStep : ∀ (n : ℕ) (p : Polynomial ℂ), 0 < p.natDegree → (∀ xi ∈ frontier (Omega n).carrier, CrouzeixBoundaryPhaseContractive (Omega n) (p /ₘ (Polynomial.X - Polynomial.C xi))) → CrouzeixBoundaryPhaseContractive (Omega n) p) (happrox : ∀ (p : Polynomial ℂ) (n : ℕ), ∃ (r : ℕ → Polynomial ℂ), ∀ (j : ℕ), ∀ z ∈ compactThickeningApprox (closure (numericalRange A)) n, ‖Polynomial.eval z (r j) - crouzeixPolynomialScalarCompanionClosedExtension (Omega n) p z‖ ≤ 1 / (↑j + 1)) (hPlemelj : ∀ (p : Polynomial ℂ) (n : ℕ), crouzeixAuxiliaryOperator A (Omega n) (crouzeixPolynomialScalarCompanionClosedExtension (Omega n) p) = crouzeixPolynomialAuxiliaryOperator A (Omega n) p) :

Automatic radial Plemelj convergence leaves only the strict-degree divided-difference induction step for the sharp boundary-phase invariant.

theorem crouzeixPalencia_of_thickening_cauchy_support_boundaryPhase_induction_radial_positiveDegree {E : Type u} [NormedAddCommGroup E] [InnerProductSpace ℂ E] [CompleteSpace E] (A : E →L[ℂ] E) (Omega : ℕ → SmoothJordanDomain) (hcarrier : ∀ (n : ℕ), (Omega n).carrier = convexThickeningApprox (closure (numericalRange A)) n) (hCauchyP : ∀ (p : Polynomial ℂ) (n : ℕ), (Polynomial.aeval A) p = (2 * ↑Real.pi * Complex.I)⁻¹ • contourIntegral (fun (z : ℂ) => Polynomial.eval z p • resolvent A z) (Omega n).boundaryParam) (hsupport : ∀ (n : ℕ), ∀ t ∈ Set.Ioc 0 (2 * Real.pi), ∀ w ∈ numericalRange A, ((starRingEnd ℂ) (-Complex.I * deriv (Omega n).boundaryParam t) * (w - (Omega n).boundaryParam t)).re ≤ 0) (hkernel : ∀ (n : ℕ), ∀ z ∈ (Omega n).carrier, crouzeixScalarCauchyKernel (Omega n) z = 1) (hphaseStep : ∀ (n : ℕ) (p : Polynomial ℂ), 0 < p.natDegree → (∀ xi ∈ frontier (Omega n).carrier, CrouzeixBoundaryPhaseContractive (Omega n) (p /ₘ (Polynomial.X - Polynomial.C xi))) → CrouzeixBoundaryPhaseContractive (Omega n) p) (happrox : ∀ (p : Polynomial ℂ) (n : ℕ), 0 < p.natDegree → ∃ (r : ℕ → Polynomial ℂ), ∀ (j : ℕ), ∀ z ∈ compactThickeningApprox (closure (numericalRange A)) n, ‖Polynomial.eval z (r j) - crouzeixPolynomialScalarCompanionClosedExtension (Omega n) p z‖ ≤ 1 / (↑j + 1)) (hPlemelj : ∀ (p : Polynomial ℂ) (n : ℕ), 0 < p.natDegree → crouzeixAuxiliaryOperator A (Omega n) (crouzeixPolynomialScalarCompanionClosedExtension (Omega n) p) = crouzeixPolynomialAuxiliaryOperator A (Omega n) p) :

Combining radial Plemelj convergence, the automatic constant case, and strict degree descent reduces every remaining companion input to positive degree.

theorem crouzeixPalencia_of_thickening_cauchy_support_normalized_boundaryPhase_radial_positiveDegree {E : Type u} [NormedAddCommGroup E] [InnerProductSpace ℂ E] [CompleteSpace E] (A : E →L[ℂ] E) (Omega : ℕ → SmoothJordanDomain) (hcarrier : ∀ (n : ℕ), (Omega n).carrier = convexThickeningApprox (closure (numericalRange A)) n) (hCauchyP : ∀ (p : Polynomial ℂ) (n : ℕ), (Polynomial.aeval A) p = (2 * ↑Real.pi * Complex.I)⁻¹ • contourIntegral (fun (z : ℂ) => Polynomial.eval z p • resolvent A z) (Omega n).boundaryParam) (hsupport : ∀ (n : ℕ), ∀ t ∈ Set.Ioc 0 (2 * Real.pi), ∀ w ∈ numericalRange A, ((starRingEnd ℂ) (-Complex.I * deriv (Omega n).boundaryParam t) * (w - (Omega n).boundaryParam t)).re ≤ 0) (hkernel : ∀ (n : ℕ), ∀ z ∈ (Omega n).carrier, crouzeixScalarCauchyKernel (Omega n) z = 1) (hphaseNormalized : ∀ (n : ℕ) (p : Polynomial ℂ), 0 < p.natDegree → polynomialSupNorm p (frontier (Omega n).carrier) = 1 → CrouzeixBoundaryPhaseContractive (Omega n) p) (happrox : ∀ (p : Polynomial ℂ) (n : ℕ), 0 < p.natDegree → ∃ (r : ℕ → Polynomial ℂ), ∀ (j : ℕ), ∀ z ∈ compactThickeningApprox (closure (numericalRange A)) n, ‖Polynomial.eval z (r j) - crouzeixPolynomialScalarCompanionClosedExtension (Omega n) p z‖ ≤ 1 / (↑j + 1)) (hPlemelj : ∀ (p : Polynomial ℂ) (n : ℕ), 0 < p.natDegree → crouzeixAuxiliaryOperator A (Omega n) (crouzeixPolynomialScalarCompanionClosedExtension (Omega n) p) = crouzeixPolynomialAuxiliaryOperator A (Omega n) p) :

After automatic radial convergence and the constant case, every remaining phase, approximation, and contour-reproduction input is restricted to positive-degree polynomials; the phase input may moreover be normalized to frontier sup norm one.

theorem crouzeixPalencia_of_thickening_cauchy_support_normalized_boundaryPhase_radialZero {E : Type u} [NormedAddCommGroup E] [InnerProductSpace ℂ E] [CompleteSpace E] (A : E →L[ℂ] E) (Omega : ℕ → SmoothJordanDomain) (hcarrier : ∀ (n : ℕ), (Omega n).carrier = convexThickeningApprox (closure (numericalRange A)) n) (hCauchyP : ∀ (p : Polynomial ℂ) (n : ℕ), (Polynomial.aeval A) p = (2 * ↑Real.pi * Complex.I)⁻¹ • contourIntegral (fun (z : ℂ) => Polynomial.eval z p • resolvent A z) (Omega n).boundaryParam) (hsupport : ∀ (n : ℕ), ∀ t ∈ Set.Ioc 0 (2 * Real.pi), ∀ w ∈ numericalRange A, ((starRingEnd ℂ) (-Complex.I * deriv (Omega n).boundaryParam t) * (w - (Omega n).boundaryParam t)).re ≤ 0) (hkernel : ∀ (n : ℕ), ∀ z ∈ (Omega n).carrier, crouzeixScalarCauchyKernel (Omega n) z = 1) (hphaseNormalized : ∀ (n : ℕ) (p : Polynomial ℂ), 0 < p.natDegree → polynomialSupNorm p (frontier (Omega n).carrier) = 1 → CrouzeixBoundaryPhaseContractive (Omega n) p) (happrox : ∀ (p : Polynomial ℂ) (n : ℕ), 0 < p.natDegree → Polynomial.eval 0 p = 0 → ∃ (r : ℕ → Polynomial ℂ), ∀ (j : ℕ), ∀ z ∈ compactThickeningApprox (closure (numericalRange A)) n, ‖Polynomial.eval z (r j) - crouzeixPolynomialScalarCompanionClosedExtension (Omega n) p z‖ ≤ 1 / (↑j + 1)) (hPlemelj : ∀ (p : Polynomial ℂ) (n : ℕ), 0 < p.natDegree → Polynomial.eval 0 p = 0 → polynomialSupNorm p (frontier (Omega n).carrier) = 1 → crouzeixAuxiliaryOperator A (Omega n) (crouzeixPolynomialScalarCompanionClosedExtension (Omega n) p) = crouzeixPolynomialAuxiliaryOperator A (Omega n) p) :

Constant-shift invariance reduces approximation to positive-degree polynomials vanishing at zero. Scaling invariance further restricts contour reproduction to that subclass at frontier sup norm one; the sharp phase input is likewise normalized to frontier sup norm one.

theorem crouzeix_palencia_of_convexThickening_cauchy_support_normalized_boundaryPhase_radial {E : Type u} [NormedAddCommGroup E] [InnerProductSpace ℂ E] [CompleteSpace E] (A : E →L[ℂ] E) (Omega : ℕ → SmoothJordanDomain) (hcarrier : ∀ (n : ℕ), (Omega n).carrier = convexThickeningApprox (closure (numericalRange A)) n) (hCauchyP : ∀ (p : Polynomial ℂ) (n : ℕ), (Polynomial.aeval A) p = (2 * ↑Real.pi * Complex.I)⁻¹ • contourIntegral (fun (z : ℂ) => Polynomial.eval z p • resolvent A z) (Omega n).boundaryParam) (hsupport : ∀ (n : ℕ), ∀ t ∈ Set.Ioc 0 (2 * Real.pi), ∀ w ∈ numericalRange A, ((starRingEnd ℂ) (-Complex.I * deriv (Omega n).boundaryParam t) * (w - (Omega n).boundaryParam t)).re ≤ 0) (hkernel : ∀ (n : ℕ), ∀ z ∈ (Omega n).carrier, crouzeixScalarCauchyKernel (Omega n) z = 1) (hphaseNormalized : ∀ (n : ℕ) (p : Polynomial ℂ), 0 < p.natDegree → polynomialSupNorm p (frontier (Omega n).carrier) = 1 → CrouzeixBoundaryPhaseContractive (Omega n) p) (happrox : ∀ (p : Polynomial ℂ) (n : ℕ), ∃ (r : ℕ → Polynomial ℂ), ∀ (j : ℕ), ∀ z ∈ compactThickeningApprox (closure (numericalRange A)) n, ‖Polynomial.eval z (r j) - crouzeixPolynomialScalarCompanionClosedExtension (Omega n) p z‖ ≤ 1 / (↑j + 1)) (hPlemelj : ∀ (p : Polynomial ℂ) (n : ℕ), crouzeixAuxiliaryOperator A (Omega n) (crouzeixPolynomialScalarCompanionClosedExtension (Omega n) p) = crouzeixPolynomialAuxiliaryOperator A (Omega n) p) :

After automatic radial Plemelj convergence and scalar normalization, the L4.2 route needs the sharp phase theorem only for positive-degree frontier-sup-norm-one polynomials.