OAI/GroupTheory/PolycyclicRecognition/Algebra/BoundedPrefixEnvelope.lean

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2 declarations, 0 contain sorry, 0 declared as axioms

Vanishing exponential error for uniformly bounded word prefixes

  1. theorem OAI.PolycyclicRecognition.exists_vanishing_exponential_envelope line 16

    Source documentation

    A constant coordinate radius can be written as an exponential envelope whose normalized exponent tends to zero along the scale sequence.

    theorem exists_vanishing_exponential_envelope
        (scale : ℕ → ℝ) (hscale : Tendsto scale atTop atTop)
        (hscale1 : ∀ n, 1 ≤ scale n) (D : ℝ) :
        ∃ ε : ℕ → ℝ, (∀ n, 0 ≤ ε n) ∧ Tendsto ε atTop (𝓝 0) ∧
          ∀ n, D ≤ Real.exp (scale n * ε n) := by
    …
  2. theorem OAI.PolycyclicRecognition.enlarged_prefix_vanishing_envelope line 36

    Source documentation

    Enlarging nonnegative word weights preserves the common prefix bound, so all prefix coordinates satisfy the vanishing exponential error required by neighboring-sheet affinity. The basis and weights may vary with scale.

    theorem enlarged_prefix_vanishing_envelope
        {L J K : Type*} [LieRing L] [LieAlgebra ℝ L] [Fintype J]
        (b : ℕ → Basis J ℝ L) (cost : ℕ → J → ℝ)
        (hcost : ∀ n j, 0 ≤ cost n j)
        (scale : ℕ → ℝ) (hscale : Tendsto scale atTop atTop)
        (hscale1 : ∀ n, 1 ≤ scale n)
        (vertex : ℕ → K → L) (D : ℝ)
        (hbound : ∀ n k,
          ‖(exponentialRescaleBasis (b n) (cost n) (scale n)).equivFun (vertex n k)‖ ≤ D)
        {δ : ℝ} (hδ : 0 ≤ δ) :
        ∃ ε : ℕ → ℝ, (∀ n, 0 ≤ ε n) ∧ Tendsto ε atTop (𝓝 0) ∧
          ∀ n k,
    …

    Mentions: OAI.PolycyclicRecognition.exponentialRescaleBasis