OAI/Geometry/SurfaceImmersion/Primitive/PeriodicNormalStability.lean
2 declarations, 0 contain sorry, 0 declared as axioms
Uniform normal margins over the compact position-period domain.
- theorem
OAI.ClosedSurfaceR4.VelocityFrame.periodic_leading_normal_stabilityline 17Source documentation
A full real fast phase costs no compactness: periodicity reduces the normal estimate to one compact period.
theorem periodic_leading_normal_stability {K : Set A} (hK : IsCompact K) {X Y C : A → Vec} (hX : Continuous X) (hY : Continuous Y) (hC : Continuous C) (V : A → C(Period, Vec)) (hVs : Continuous (fun p : A × ℝ => V p.1 (p.2 : Period))) (hD : ∀ p ∈ K, gramDet (Y p) (C p) ≠ 0) (hYV : ∀ p ∈ K, ∀ θ : Period, Y p ⬝ᵥ V p θ = 0) (hCV : ∀ p ∈ K, ∀ θ : Period, C p ⬝ᵥ V p θ = 0) (hV0 : ∀ p ∈ K, ∀ θ : Period, V p θ ≠ 0) : ∃ ε c : ℝ, 0 < ε ∧ 0 < c ∧ ∀ p ∈ K, ∀ t : ℝ, ∀ H : NormalTriple, ‖H-![leadingTangent (X p) (Y p) (C p) (V p (t : Period)),Y p,C p]‖ < ε → gramDet (H 0) (H 1) ≠ 0 ∧ c < ‖realNormalPart (H 0) (H 1) (H 2)‖ := by …Mentions: OAI.ClosedSurfaceR4.VelocityFrame.NormalTriple, OAI.ClosedSurfaceR4.VelocityFrame.leadingTangent
- theorem
OAI.ClosedSurfaceR4.VelocityFrame.periodic_normal_stability_of_linear_errorline 46Source documentation
Componentwise
O(z)errors in x, y and yy preserve a uniform normal margin for all sufficiently small fast scales.theorem periodic_normal_stability_of_linear_error {K : Set A} (hK : IsCompact K) {X Y C : A → Vec} (hX : Continuous X) (hY : Continuous Y) (hC : Continuous C) (V : A → C(Period, Vec)) (hVs : Continuous (fun p : A × ℝ => V p.1 (p.2 : Period))) (hD : ∀ p ∈ K, gramDet (Y p) (C p) ≠ 0) (hYV : ∀ p ∈ K, ∀ θ : Period, Y p ⬝ᵥ V p θ = 0) (hCV : ∀ p ∈ K, ∀ θ : Period, C p ⬝ᵥ V p θ = 0) (hV0 : ∀ p ∈ K, ∀ θ : Period, V p θ ≠ 0) (D : ℝ) (hD0 : 0 ≤ D) : ∃ η c : ℝ, 0 < η ∧ 0 < c ∧ ∀ z : ℝ, 0 < z → z < η → ∀ p ∈ K, ∀ t : ℝ, ∀ x y b : Vec, ‖x-leadingTangent (X p) (Y p) (C p) (V p (t : Period))‖ ≤ D*z → …