OAI/Analysis/NuclearUltrapower/Laplacian.lean

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7 declarations, 0 contain sorry, 0 declared as axioms

  1. def OAI.NuclearUltrapower.laplacian line 15

    Source documentation

    sum of squared unitary displacements.

    def laplacian (S : Finset Γ) (u : Γ → A) : A :=
    …
  2. theorem OAI.NuclearUltrapower.laplacian_nonneg line 18
  3. theorem OAI.NuclearUltrapower.laplacian_selfAdjoint line 21
  4. theorem OAI.NuclearUltrapower.laplacian_le line 24
  5. theorem OAI.NuclearUltrapower.laplacian_complement_norm line 40

    Source documentation

    The norm form used for passing a positive lower bound through nuclearity.

    theorem laplacian_complement_norm (S : Finset Γ) (u : Γ → unitary A)
        {b : ℝ} (hb : b ≤ 4 * (S.card : ℝ))
        (hgap : b • (1:A) ≤ laplacian S (fun s => (u s : A))) :
        ‖(4 * (S.card : ℝ)) • (1:A) - laplacian S (fun s => (u s : A))‖ ≤
          4 * (S.card : ℝ) - b := by
    …

    Mentions: OAI.NuclearUltrapower.laplacian

  6. theorem OAI.NuclearUltrapower.laplacian_inner line 56

    Source documentation

    The quadratic form is exactly the energy, with no representation relations.

    theorem laplacian_inner (S : Finset Γ) (u : Γ → (H →L[ℂ] H)) (x : H) :
        inner ℂ x (laplacian S u x) = (∑ s ∈ S, ‖u s x - x‖ ^ 2 : ℝ) := by
    …

    Mentions: OAI.NuclearUltrapower.laplacian

  7. theorem OAI.NuclearUltrapower.laplacian_lower_iff line 63

    Source documentation

    Real quadratic forms detect the operator lower bound.

    theorem laplacian_lower_iff (S : Finset Γ) (u : Γ → (H →L[ℂ] H)) (b : ℝ) :
        b • (1 : H →L[ℂ] H) ≤ laplacian S u ↔
          ∀ x, b * ‖x‖ ^ 2 ≤ ∑ s ∈ S, ‖u s x - x‖ ^ 2 := by
    …

    Mentions: OAI.NuclearUltrapower.laplacian