OAI/GroupTheory/PolycyclicRecognition/Analysis/SublinearRayIdentification.lean

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2 declarations, 0 contain sorry, 0 declared as axioms

Identifying bounded trace errors along linearly growing height rays

  1. theorem OAI.PolycyclicRecognition.sublinear_error_on_linear_ray line 12

    Source documentation

    A metric sublinear error restricts to a sublinear error on every ray of at most linear metric growth. The additive constant may depend on the ray.

    theorem sublinear_error_on_linear_ray
        {X W : Type*} [PseudoMetricSpace X] [NormedAddCommGroup W]
        (base : X) (error : X → W) (ray : ℝ → X)
        (herror : ∀ ε : ℝ, 0 < ε → ∃ B : ℝ, ∀ x,
          ‖error x‖ ≤ ε * dist base x + B)
        {L C : ℝ} (hL : 0 ≤ L)
        (hmetric : ∀ t : ℝ, 0 ≤ t → dist base (ray t) ≤ L * t + C) :
        ∀ ε : ℝ, 0 < ε → ∃ R : ℝ, ∀ t : ℝ, R ≤ t → 0 ≤ t →
          ‖error (ray t)‖ ≤ ε * t := by
    …
  2. theorem OAI.PolycyclicRecognition.uniform_transversal_affine_bound_of_ray_traces line 39

    Source documentation

    Averaging gives bounded trace errors with the source character. A sublinear comparison along height rays identifies each source character with the corresponding target character composed with the affine label.

    theorem uniform_transversal_affine_bound_of_ray_traces
        {P G D W I : Type*} [NormedAddCommGroup W] [NormedSpace ℝ W]
        [FiniteDimensional ℝ W] [Fintype I]
        (α β : I → Module.Dual ℝ W)
        (hsep : ∀ w, (∀ i, β i w = 0) → w = 0)
        (height : G → W) (η : P → G → W) (A : P → W →ₗ[ℝ] W)
        (d : D → G) (j₀ : D) (ray : W → ℝ → D)
        (hray : ∀ w t, height (d (ray w t)) = t • w)
        {B : ℝ} (hB : 0 ≤ B)
        (htrace : ∀ p j i,
          |β i (η p (d j) - η p (d j₀)) - α i (height (d j))| ≤ B)
        (hsub : ∀ p w ε, 0 < ε → ∃ R : ℝ, ∀ t, R ≤ t → 0 ≤ t →
    …