OAI/Analysis/AffineBernstein/HessianDivergence.lean

GitHub source file

4 declarations, 0 contain sorry, 0 declared as axioms

  1. theorem OAI.AffineBernstein.adjugate_hessian_divergence line 13

    Source documentation

    Smoothness through order three suffices for the cofactor cancellation.

    theorem adjugate_hessian_divergence {n : ℕ} (u : Space n → ℝ) (x : Space n)
        (hu : ContDiffAt ℝ 3 u x) (i : Fin n) :
        (∑ j, fderiv ℝ (fun y => (hessian u y).adjugate i j) x
          (coordinateVector n j)) = 0 := by
    …

    Mentions: OAI.AffineBernstein.Space, OAI.AffineBernstein.hessian, OAI.AffineBernstein.coordinateVector

  2. theorem OAI.AffineBernstein.cofactorHessian_eq_adjugate line 26

    Source documentation

    For an invertible Hessian, the manuscript's definition is exactly the adjugate.

    theorem cofactorHessian_eq_adjugate {n : ℕ} (u : Space n → ℝ) (x : Space n)
        (hdet : (hessian u x).det ≠ 0) : cofactorHessian u x = (hessian u x).adjugate := by
    …

    Mentions: OAI.AffineBernstein.Space, OAI.AffineBernstein.hessian, OAI.AffineBernstein.cofactorHessian

  3. theorem OAI.AffineBernstein.cofactorHessian_isSymm line 32

    Source documentation

    The Hessian cofactor is symmetric under the standing positivity hypothesis.

    theorem cofactorHessian_isSymm {n : ℕ} (u : Space n → ℝ) (x : Space n)
        (hpos : (hessian u x).PosDef) : (cofactorHessian u x).IsSymm := by
    …

    Mentions: OAI.AffineBernstein.Space, OAI.AffineBernstein.hessian, OAI.AffineBernstein.cofactorHessian

  4. theorem OAI.AffineBernstein.cofactorHessian_divergence line 38

    Source documentation

    Both divergences of the actual coefficient matrix vanish on the original domain.

    theorem cofactorHessian_divergence {n : ℕ} {Ω : Set (Space n)} (hΩ : IsOpen Ω)
        (u : Space n → ℝ) (hu : ContDiffOn ℝ 3 u Ω)
        (hpos : ∀ x ∈ Ω, (hessian u x).PosDef) (x : Space n) (hx : x ∈ Ω) (i : Fin n) :
        (∑ j, fderiv ℝ (fun y => cofactorHessian u y i j) x (coordinateVector n j)) = 0 ∧
        (∑ j, fderiv ℝ (fun y => cofactorHessian u y j i) x (coordinateVector n j)) = 0 := by
    …

    Mentions: OAI.AffineBernstein.Space, OAI.AffineBernstein.hessian, OAI.AffineBernstein.cofactorHessian, OAI.AffineBernstein.coordinateVector