OAI/Geometry/RCD/Metric/NoExtraFactor.lean

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2 declarations, 0 contain sorry, 0 declared as axioms

The quantitative no-extra-factor hypothesis

An approximation by R^n excludes a product with an R^(n+1) factor, at a fixed positive dimensional tolerance, giving the non-extra-factor hypothesis in the Huang--Huang transformation theorem.

  1. def OAI.RegularPointCoordinates.NoExtraEuclideanFactor line 22

    Source documentation

    The ball-map form of the no-(n+1)-Euclidean condition.

    def NoExtraEuclideanFactor {X : Type u} [MetricSpace X]
        (n : ℕ) (p : X) (r η : ℝ) : Prop :=
    …
  2. theorem OAI.RegularPointCoordinates.noExtraEuclideanFactor_of_approximation line 29

    Source documentation

    A single explicit tolerance works at every center and scale.

    theorem noExtraEuclideanFactor_of_approximation {X : Type u} [MetricSpace X]
        (n : ℕ) {p : X} {r δ : ℝ} (_hr : 0 < r) (hδ : 0 ≤ δ)
        (hsmall : δ ≤ 1 / (100 * ((n + 1 : ℕ) : ℝ) ^ 2))
        (f : X → Euclidean n) (hf : IsPointedApproximation p 0 r 1 δ f) :
        NoExtraEuclideanFactor n p r (1 / (100 * ((n + 1 : ℕ) : ℝ) ^ 2)) := by
    …

    Mentions: OAI.RegularPointCoordinates.Euclidean, OAI.RegularPointCoordinates.IsPointedApproximation, OAI.RegularPointCoordinates.NoExtraEuclideanFactor