OAI/Analysis/NuclearUltrapower/Laplacian.lean
7 declarations, 0 contain sorry, 0 declared as axioms
- def
OAI.NuclearUltrapower.laplacianline 15Source documentation
sum of squared unitary displacements.
def laplacian (S : Finset Γ) (u : Γ → A) : A := …
- theorem
OAI.NuclearUltrapower.laplacian_nonnegline 18 - theorem
OAI.NuclearUltrapower.laplacian_selfAdjointline 21 - theorem
OAI.NuclearUltrapower.laplacian_leline 24 - theorem
OAI.NuclearUltrapower.laplacian_complement_normline 40Source 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
- theorem
OAI.NuclearUltrapower.laplacian_innerline 56Source 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
- theorem
OAI.NuclearUltrapower.laplacian_lower_iffline 63Source 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