OAI/Analysis/AffineBernstein/DeterminantVariation.lean
44 declarations, 0 contain sorry, 0 declared as axioms
- theorem
OAI.AffineBernstein.hasDerivAt_det_lineline 18Source documentation
Jacobi's formula without assuming invertibility of the varied matrix.
theorem hasDerivAt_det_line (A B : Matrix ι ι ℝ) : HasDerivAt (fun t : ℝ => (A + t • B).det) (∑ i, ∑ j, A.adjugate j i * B i j) 0 := by … - theorem
OAI.AffineBernstein.hasDerivAt_affineArea_matrixline 41Source documentation
Pointwise first variation of the actual affine-area density.
theorem hasDerivAt_affineArea_matrix (A B : Matrix ι ι ℝ) (hA : A.PosDef) (δ : ℝ) : HasDerivAt (fun t : ℝ => Real.rpow (A + t • B).det δ) (δ * Real.rpow A.det (δ - 1) * (∑ i, ∑ j, A.adjugate j i * B i j)) 0 := by … - theorem
OAI.AffineBernstein.contDiff_of_contDiffAt_tsupportline 58Source documentation
Away from topological support the test is locally zero, so no extension of a smooth coefficient across the original boundary is necessary.
theorem contDiff_of_contDiffAt_tsupport {f : E → ℝ} {k : ℕ∞ω} (hf : ∀ x ∈ tsupport f, ContDiffAt ℝ k f x) : ContDiff ℝ k f := by … - theorem
OAI.AffineBernstein.dirDeriv_eq_secondline 68Source documentation
Commuting fixed-direction differentiation with evaluation of a derivative.
theorem dirDeriv_eq_second {f : E → ℝ} {x : E} (hf : ContDiffAt ℝ ∞ f x) (v z : E) : dirDeriv v (dirDeriv z f) x = fderiv ℝ (fderiv ℝ f) x v z := by …Mentions: OAI.AffineBernstein.dirDeriv
- theorem
OAI.AffineBernstein.dirDeriv_commline 77Source documentation
Symmetry of the second derivative in fixed directions.
theorem dirDeriv_comm {f : E → ℝ} {x : E} (hf : ContDiffAt ℝ ∞ f x) (v z : E) : dirDeriv v (dirDeriv z f) x = dirDeriv z (dirDeriv v f) x := by …Mentions: OAI.AffineBernstein.dirDeriv
- def
OAI.AffineBernstein.radialSupportline 83Source documentation
The support-plane height
ν(o-X)in original graph coordinates.def radialSupport (u : E → ℝ) (o : E) (c : ℝ) (x : E) : ℝ := …
- theorem
OAI.AffineBernstein.contDiffAt_radialSupportline 87Source documentation
Smoothness holds only locally; the eventual zero argument handles tests.
theorem contDiffAt_radialSupport {u : E → ℝ} {x : E} (hu : ContDiffAt ℝ ∞ u x) (o : E) (c : ℝ) : ContDiffAt ℝ ∞ (radialSupport u o c) x := …Mentions: OAI.AffineBernstein.radialSupport
- theorem
OAI.AffineBernstein.dirDeriv_radialGradientline 94Source documentation
The derivative of the radial gradient, including its moving vector argument.
theorem dirDeriv_radialGradient {u : E → ℝ} {x : E} (hu : ContDiffAt ℝ ∞ u x) (o v : E) : dirDeriv v (fun y => fderiv ℝ u y (y - o)) x = dirDeriv (x - o) (dirDeriv v u) x + dirDeriv v u x := by …Mentions: OAI.AffineBernstein.dirDeriv
- theorem
OAI.AffineBernstein.dirDeriv_radialSupportline 109Source documentation
The cancellation
D Z = H(x-o)with no coordinate or global extension assumption.theorem dirDeriv_radialSupport {u : E → ℝ} {x : E} (hu : ContDiffAt ℝ ∞ u x) (o : E) (c : ℝ) (v : E) : dirDeriv v (radialSupport u o c) x = dirDeriv (x - o) (dirDeriv v u) x := by …Mentions: OAI.AffineBernstein.dirDeriv, OAI.AffineBernstein.radialSupport
- theorem
OAI.AffineBernstein.second_dirDeriv_radialSupportline 128Source documentation
The exact second derivative of the support-plane height.
theorem second_dirDeriv_radialSupport {Ω : Set E} (hΩ : IsOpen Ω) {u : E → ℝ} (hu : ContDiffOn ℝ ∞ u Ω) {x : E} (hx : x ∈ Ω) (o : E) (c : ℝ) (v z : E) : dirDeriv z (dirDeriv v (radialSupport u o c)) x = dirDeriv z (dirDeriv v u) x + dirDeriv (x - o) (dirDeriv z (dirDeriv v u)) x := by …Mentions: OAI.AffineBernstein.dirDeriv, OAI.AffineBernstein.radialSupport
- theorem
OAI.AffineBernstein.hessian_radialSupportline 146Source documentation
The coordinate version used in the trace of the cap test.
theorem hessian_radialSupport {n : ℕ} {Ω : Set (Space n)} (hΩ : IsOpen Ω) {u : Space n → ℝ} (hu : ContDiffOn ℝ ∞ u Ω) {x : Space n} (hx : x ∈ Ω) (o : Space n) (c : ℝ) (i j : Fin n) : hessian (radialSupport u o c) x i j = hessian u x i j + dirDeriv (x - o) (fun y => hessian u y i j) x := …Mentions: OAI.AffineBernstein.Space, OAI.AffineBernstein.hessian, OAI.AffineBernstein.radialSupport, OAI.AffineBernstein.dirDeriv
- theorem
OAI.AffineBernstein.dirDeriv_detline 154Source documentation
Jacobi's formula in arbitrary fixed directions, for the actual entries.
theorem dirDeriv_det {E ι : Type*} [NormedAddCommGroup E] [NormedSpace ℝ E] [Fintype ι] [DecidableEq ι] (A : E → Matrix ι ι ℝ) {x : E} (hA : ∀ i j, DifferentiableAt ℝ (fun y => A y i j) x) (v : E) : dirDeriv v (fun y => (A y).det) x = ∑ i, ∑ j, (A x).adjugate j i * dirDeriv v (fun y => A y i j) x := by …Mentions: OAI.AffineBernstein.dirDeriv
- theorem
OAI.AffineBernstein.contDiffAt_affineAreaDensityline 176Source documentation
Smoothness of the area density on the original domain.
theorem contDiffAt_affineAreaDensity {n : ℕ} {u : Space n → ℝ} {x : Space n} (hu : ContDiffAt ℝ ∞ u x) (hpos : (hessian u x).PosDef) : ContDiffAt ℝ ∞ (affineAreaDensity u) x := …Mentions: OAI.AffineBernstein.Space, OAI.AffineBernstein.hessian, OAI.AffineBernstein.affineAreaDensity
- theorem
OAI.AffineBernstein.dirDeriv_affineAreaDensityline 182Source documentation
The exact differential of the affine area coefficient.
theorem dirDeriv_affineAreaDensity {n : ℕ} {u : Space n → ℝ} {x : Space n} (hu : ContDiffAt ℝ ∞ u x) (hpos : (hessian u x).PosDef) (v : Space n) : dirDeriv v (affineAreaDensity u) x = (1 / ((n : ℝ) + 2)) * affineAreaDensity u x * (∑ i, ∑ j, (hessian u x)⁻¹ i j * dirDeriv v (fun y => hessian u y i j) x) := by …Mentions: OAI.AffineBernstein.Space, OAI.AffineBernstein.hessian, OAI.AffineBernstein.dirDeriv, OAI.AffineBernstein.affineAreaDensity
- theorem
OAI.AffineBernstein.trace_inverse_mul_selfline 216Source documentation
Trace of the identity, in the entry convention used in the manuscript.
theorem trace_inverse_mul_self {n : ℕ} {H : Matrix (Fin n) (Fin n) ℝ} (hH : H.PosDef) : (∑ i, ∑ j, H⁻¹ i j * H i j) = (n : ℝ) := by … - theorem
OAI.AffineBernstein.weighted_trace_radialSupportline 231Source documentation
Weighted radial trace, avoiding a logarithm at points outside the domain.
theorem weighted_trace_radialSupport {n : ℕ} {Ω : Set (Space n)} (hΩ : IsOpen Ω) {u : Space n → ℝ} (hu : ContDiffOn ℝ ∞ u Ω) {x : Space n} (hx : x ∈ Ω) (hpos : (hessian u x).PosDef) (o : Space n) (c : ℝ) : affineAreaDensity u x * (∑ i, ∑ j, (hessian u x)⁻¹ i j * hessian (radialSupport u o c) x i j) = n * affineAreaDensity u x + ((n : ℝ) + 2) * dirDeriv (x - o) (affineAreaDensity u) x := by …Mentions: OAI.AffineBernstein.Space, OAI.AffineBernstein.hessian, OAI.AffineBernstein.affineAreaDensity, OAI.AffineBernstein.radialSupport, OAI.AffineBernstein.dirDeriv
- theorem
OAI.AffineBernstein.sum_coordinateVectorline 245Source documentation
Expansion in the frozen Euclidean coordinate vectors.
theorem sum_coordinateVector {n : ℕ} (v : Space n) : (∑ i, (v i) • coordinateVector n i) = v := by …Mentions: OAI.AffineBernstein.Space, OAI.AffineBernstein.coordinateVector
- theorem
OAI.AffineBernstein.clm_coordinate_sumline 251Source documentation
Linear functionals are recovered exactly by coordinates.
theorem clm_coordinate_sum {n : ℕ} (L : Space n →L[ℝ] ℝ) (v : Space n) : L v = ∑ i, v i * L (coordinateVector n i) := by …Mentions: OAI.AffineBernstein.Space, OAI.AffineBernstein.coordinateVector
- theorem
OAI.AffineBernstein.dirDeriv_coordinate_sumline 257Source documentation
The radial vector derivative is the sum of its coordinate derivatives.
theorem dirDeriv_coordinate_sum {n : ℕ} (f : Space n → ℝ) (x v : Space n) : dirDeriv v f x = ∑ i, v i * dirDeriv (coordinateVector n i) f x := …Mentions: OAI.AffineBernstein.Space, OAI.AffineBernstein.dirDeriv, OAI.AffineBernstein.coordinateVector
- theorem
OAI.AffineBernstein.second_dirDeriv_mulline 262Source documentation
A second derivative product rule on the actual open domain.
theorem second_dirDeriv_mul {E : Type*} [NormedAddCommGroup E] [NormedSpace ℝ E] {Ω : Set E} (hΩ : IsOpen Ω) {f g : E → ℝ} (hf : ContDiffOn ℝ ∞ f Ω) (hg : ContDiffOn ℝ ∞ g Ω) {x : E} (hx : x ∈ Ω) (v z : E) : dirDeriv z (dirDeriv v (fun y => f y * g y)) x = dirDeriv z (dirDeriv v f) x * g x + dirDeriv v f x * dirDeriv z g x + dirDeriv z f x * dirDeriv v g x + f x * dirDeriv z (dirDeriv v g) x := by …Mentions: OAI.AffineBernstein.dirDeriv
- theorem
OAI.AffineBernstein.dirDeriv_comp_scalarline 291Source documentation
Scalar composition by its actual one-dimensional derivative.
theorem dirDeriv_comp_scalar {E : Type*} [NormedAddCommGroup E] [NormedSpace ℝ E] {q : E → ℝ} {ψ : ℝ → ℝ} {x : E} (hq : DifferentiableAt ℝ q x) (hψ : DifferentiableAt ℝ ψ (q x)) (v : E) : dirDeriv v (fun y => ψ (q y)) x = deriv ψ (q x) * dirDeriv v q x := by …Mentions: OAI.AffineBernstein.dirDeriv
- theorem
OAI.AffineBernstein.second_dirDeriv_comp_scalarline 301Source documentation
The second chain rule used by a cap test.
theorem second_dirDeriv_comp_scalar {E : Type*} [NormedAddCommGroup E] [NormedSpace ℝ E] {Ω : Set E} (hΩ : IsOpen Ω) {q : E → ℝ} {ψ : ℝ → ℝ} (hq : ContDiffOn ℝ ∞ q Ω) (hψ : ContDiff ℝ ∞ ψ) {x : E} (hx : x ∈ Ω) (v z : E) : dirDeriv z (dirDeriv v (fun y => ψ (q y))) x = deriv (deriv ψ) (q x) * dirDeriv z q x * dirDeriv v q x + deriv ψ (q x) * dirDeriv z (dirDeriv v q) x := by …Mentions: OAI.AffineBernstein.dirDeriv
- def
OAI.AffineBernstein.graphAffineFunctionline 326Source documentation
Restriction of an arbitrary ambient affine function to the original graph.
def graphAffineFunction {n : ℕ} (u : Space n → ℝ) (a : Space n →L[ℝ] ℝ) (b d : ℝ) (x : Space n) : ℝ := a x + b * u x + dMentions: OAI.AffineBernstein.Space
- theorem
OAI.AffineBernstein.contDiffAt_graphAffineFunctionline 329 - theorem
OAI.AffineBernstein.dirDeriv_graphAffineFunctionline 334 - theorem
OAI.AffineBernstein.hessian_graphAffineFunctionline 342 - theorem
OAI.AffineBernstein.matrix_pair_eq_dotline 359Source documentation
Coordinate pairing equals the ordinary matrix-vector contraction.
theorem matrix_pair_eq_dot {ι : Type*} [Fintype ι] (A : Matrix ι ι ℝ) (p q : ι → ℝ) : (∑ i, ∑ j, A i j * p i * q j) = p ⬝ᵥ (A.mulVec q) := by … - theorem
OAI.AffineBernstein.matrix_pair_symmline 370Source documentation
Symmetry of the covector contraction, with the literal matrix coefficients.
theorem matrix_pair_symm {ι : Type*} [Fintype ι] {A : Matrix ι ι ℝ} (hA : A.IsSymm) (p q : ι → ℝ) : (∑ i, ∑ j, A i j * p i * q j) = ∑ i, ∑ j, A i j * q i * p j := by … - theorem
OAI.AffineBernstein.inverse_radial_contractionline 382Source documentation
Exact inverse contraction for a radial vector and a covector.
theorem inverse_radial_contraction {ι : Type*} [Fintype ι] [DecidableEq ι] {H : Matrix ι ι ℝ} (hH : H.PosDef) (v p : ι → ℝ) : (∑ i, ∑ j, H⁻¹ i j * (∑ k, v k * H k i) * p j) = ∑ i, v i * p i := by … - theorem
OAI.AffineBernstein.inverseHessian_radialSupportline 392Source documentation
The radial support gradient cancels exactly against the inverse Hessian.
theorem inverseHessian_radialSupport {n : ℕ} {u : Space n → ℝ} {x : Space n} (hu : ContDiffAt ℝ ∞ u x) (hpos : (hessian u x).PosDef) (o : Space n) (c : ℝ) (q : Space n → ℝ) : (∑ i, ∑ j, (hessian u x)⁻¹ i j * dirDeriv (coordinateVector n i) (radialSupport u o c) x * dirDeriv (coordinateVector n j) q x) = dirDeriv (x - o) q x := by …Mentions: OAI.AffineBernstein.Space, OAI.AffineBernstein.hessian, OAI.AffineBernstein.dirDeriv, OAI.AffineBernstein.coordinateVector, OAI.AffineBernstein.radialSupport
- theorem
OAI.AffineBernstein.hessian_product_traceline 407Source documentation
Product trace in coordinates.
theorem hessian_product_trace {n : ℕ} {Ω : Set (Space n)} (hΩ : IsOpen Ω) {f g : Space n → ℝ} (hf : ContDiffOn ℝ ∞ f Ω) (hg : ContDiffOn ℝ ∞ g Ω) {x : Space n} (hx : x ∈ Ω) {A : Matrix (Fin n) (Fin n) ℝ} (hA : A.IsSymm) : (∑ i, ∑ j, A i j * hessian (fun y => f y * g y) x i j) = g x * (∑ i, ∑ j, A i j * hessian f x i j) + f x * (∑ i, ∑ j, A i j * hessian g x i j) + 2 * (∑ i, ∑ j, A i j * dirDeriv (coordinateVector n i) f x * dirDeriv (coordinateVector n j) g x) := by …Mentions: OAI.AffineBernstein.Space, OAI.AffineBernstein.hessian, OAI.AffineBernstein.dirDeriv, OAI.AffineBernstein.coordinateVector
- theorem
OAI.AffineBernstein.hessian_composition_traceline 456Source documentation
Chain trace in coordinates.
theorem hessian_composition_trace {n : ℕ} {Ω : Set (Space n)} (hΩ : IsOpen Ω) {q : Space n → ℝ} {ψ : ℝ → ℝ} (hq : ContDiffOn ℝ ∞ q Ω) (hψ : ContDiff ℝ ∞ ψ) {x : Space n} (hx : x ∈ Ω) (A : Matrix (Fin n) (Fin n) ℝ) : (∑ i, ∑ j, A i j * hessian (fun y => ψ (q y)) x i j) = deriv (deriv ψ) (q x) * (∑ i, ∑ j, A i j * dirDeriv (coordinateVector n i) q x * dirDeriv (coordinateVector n j) q x) + deriv ψ (q x) * (∑ i, ∑ j, A i j * hessian q x i j) := by …Mentions: OAI.AffineBernstein.Space, OAI.AffineBernstein.hessian, OAI.AffineBernstein.dirDeriv, OAI.AffineBernstein.coordinateVector
- theorem
OAI.AffineBernstein.inverseHessian_isSymmline 473Source documentation
Positivity fixes the inverse-Hessian symmetry employed in a cap test.
theorem inverseHessian_isSymm {n : ℕ} {u : Space n → ℝ} {x : Space n} (hpos : (hessian u x).PosDef) : ((hessian u x)⁻¹).IsSymm := …Mentions: OAI.AffineBernstein.Space, OAI.AffineBernstein.hessian
- theorem
OAI.AffineBernstein.weighted_trace_capTestline 478Source documentation
Pointwise first-variation integrand of the source cap test.
theorem weighted_trace_capTest {n : ℕ} {Ω : Set (Space n)} (hΩ : IsOpen Ω) {u : Space n → ℝ} (hu : ContDiffOn ℝ ∞ u Ω) {x : Space n} (hx : x ∈ Ω) (hpos : (hessian u x).PosDef) (o : Space n) (c : ℝ) (a : Space n →L[ℝ] ℝ) (b d : ℝ) {ψ : ℝ → ℝ} (hψ : ContDiff ℝ ∞ ψ) : let q := graphAffineFunction u a b d …Mentions: OAI.AffineBernstein.Space, OAI.AffineBernstein.hessian, OAI.AffineBernstein.graphAffineFunction
- theorem
OAI.AffineBernstein.cap_affine_cancellationline 537Source documentation
Cancellation of the affine coefficients in the first variation.
theorem cap_affine_cancellation {n : ℕ} {u : Space n → ℝ} {x : Space n} (hu : DifferentiableAt ℝ u x) (o : Space n) (c : ℝ) (a : Space n →L[ℝ] ℝ) (b d : ℝ) : radialSupport u o c x * b - dirDeriv (x - o) (graphAffineFunction u a b d) x = (a o + b * c + d) - graphAffineFunction u a b d x := by …Mentions: OAI.AffineBernstein.Space, OAI.AffineBernstein.radialSupport, OAI.AffineBernstein.dirDeriv, OAI.AffineBernstein.graphAffineFunction
- def
OAI.AffineBernstein.coordinateProjectionline 547Source documentation
The actual coordinate functional through the Euclidean-space equivalence.
def coordinateProjection (n : ℕ) (i : Fin n) : Space n →L[ℝ] ℝ := …
Mentions: OAI.AffineBernstein.Space
- theorem
OAI.AffineBernstein.coordinateProjection_applyline 550 - theorem
OAI.AffineBernstein.contDiff_mul_at_tsupportline 554Source documentation
A smooth compact test makes a merely locally smooth coefficient globally smooth.
theorem contDiff_mul_at_tsupport {E : Type*} [NormedAddCommGroup E] [NormedSpace ℝ E] {f g : E → ℝ} {k : ℕ∞ω} (hg : ContDiff ℝ k g) (hf : ∀ x ∈ tsupport g, ContDiffAt ℝ k f x) : ContDiff ℝ k (fun x => f x * g x) := by … - theorem
OAI.AffineBernstein.integral_dirDeriv_compactline 563Source documentation
Integral of a derivative of a smooth compactly supported scalar field.
theorem integral_dirDeriv_compact {E : Type*} [NormedAddCommGroup E] [NormedSpace ℝ E] [FiniteDimensional ℝ E] [MeasurableSpace E] [BorelSpace E] {μ : Measure E} [μ.IsAddHaarMeasure] (f : E → ℝ) (hf : ContDiff ℝ ∞ f) (hfc : HasCompactSupport f) (v : E) : (∫ x, dirDeriv v f x ∂μ) = 0 := by …Mentions: OAI.AffineBernstein.dirDeriv
- theorem
OAI.AffineBernstein.integral_radial_divergence_compactline 575Source documentation
Radial integration by parts with a compact test and no global extension of
f. This formulation gives integrability as well as the identity.theorem integral_radial_divergence_compact {n : ℕ} {μ : Measure (Space n)} [μ.IsAddHaarMeasure] (f σ : Space n → ℝ) (o : Space n) (hσ : ContDiff ℝ ∞ σ) (hσc : HasCompactSupport σ) (hf : ∀ x ∈ tsupport σ, ContDiffAt ℝ ∞ f x) : let D := fun x => dirDeriv (x - o) f x * σ x + …Mentions: OAI.AffineBernstein.Space, OAI.AffineBernstein.dirDeriv
- theorem
OAI.AffineBernstein.contDiff_indicator_of_compactline 654Source documentation
Zero-extension of a compactly supported local test is genuinely smooth on the ambient coordinate space; no extension theorem for the graph is needed.
theorem contDiff_indicator_of_compact {E : Type*} [NormedAddCommGroup E] [NormedSpace ℝ E] {Ω K : Set E} (hΩ : IsOpen Ω) (hK : IsCompact K) (hKΩ : K ⊆ Ω) {f : E → ℝ} {k : ℕ∞ω} (hf : ContDiffOn ℝ k f Ω) (hz : ∀ x ∈ Ω, x ∉ K → f x = 0) : ContDiff ℝ k (Ω.indicator f) ∧ HasCompactSupport (Ω.indicator f) ∧ tsupport (Ω.indicator f) ⊆ K := by … - theorem
OAI.AffineBernstein.hessian_eq_of_eventuallyEqline 677Source documentation
Hessians depend only on the germ of a function, also with the total derivative convention at points outside the domain.
theorem hessian_eq_of_eventuallyEq {n : ℕ} {f g : Space n → ℝ} {x : Space n} (h : f =ᶠ[nhds x] g) : hessian f x = hessian g x := by …Mentions: OAI.AffineBernstein.Space, OAI.AffineBernstein.hessian
- theorem
OAI.AffineBernstein.integrableOn_area_variationline 686Source documentation
The actual first-variation density is integrable for a compact local test.
theorem integrableOn_area_variation {n : ℕ} {Ω : Set (Space n)} (hΩ : IsOpen Ω) {u : Space n → ℝ} (hu : ContDiffOn ℝ ∞ u Ω) (hpos : ∀ y ∈ Ω, (hessian u y).PosDef) (η : Space n → ℝ) (hη : ContDiff ℝ ∞ η) (hηc : HasCompactSupport η) (hηΩ : tsupport η ⊆ Ω) : IntegrableOn (fun x => affineAreaDensity u x * (∑ i, ∑ j, (hessian u x)⁻¹ i j * hessian η x i j)) Ω := by …Mentions: OAI.AffineBernstein.Space, OAI.AffineBernstein.hessian, OAI.AffineBernstein.affineAreaDensity
- theorem
OAI.AffineBernstein.affineMaximal_graph_cap_identityline 719Source documentation
The cap identity in the original graph coordinates (source
area.tex, Lemma Cap identity). The source assumes compact support of all three displayed scalar compositions; this proof in fact only needs the first support condition. The measure here is precisely affine area density times Lebesgue measure.theorem affineMaximal_graph_cap_identity {n : ℕ} {Ω : Set (Space n)} (hΩ : IsOpen Ω) {u : Space n → ℝ} (hu : ContDiffOn ℝ ∞ u Ω) (hpos : ∀ y ∈ Ω, (hessian u y).PosDef) (hmax : AffineMaximalOn Ω u) (o : Space n) (c : ℝ) (a : Space n →L[ℝ] ℝ) (b d : ℝ) {ψ : ℝ → ℝ} (hψ : ContDiff ℝ ∞ ψ) {K : Set (Space n)} (hK : IsCompact K) (hKΩ : K ⊆ Ω) (hsupport : ∀ x ∈ Ω, x ∉ K → ψ (graphAffineFunction u a b d x) = 0) : (∫ x in Ω, affineAreaDensity u x * (radialSupport u o c x * (∑ i, ∑ j, (hessian u x)⁻¹ i j * dirDeriv (coordinateVector n i) (graphAffineFunction u a b d) x * dirDeriv (coordinateVector n j) (graphAffineFunction u a b d) x) * …Mentions: OAI.AffineBernstein.Space, OAI.AffineBernstein.hessian, OAI.AffineBernstein.AffineMaximalOn, OAI.AffineBernstein.graphAffineFunction, OAI.AffineBernstein.affineAreaDensity, OAI.AffineBernstein.radialSupport, OAI.AffineBernstein.dirDeriv, OAI.AffineBernstein.coordinateVector