OAI/GroupTheory/PolycyclicRecognition/Analysis/NilpotentChainPacking.lean

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2 declarations, 0 contain sorry, 0 declared as axioms

Polynomial packing of nilpotent chains

The logarithmic endpoint estimate and exponential-coordinate Haar formula supply actual finite polynomial bounds on separated chains. Only the precise published nilpotent exponential inputs are used.

  1. theorem OAI.PolycyclicRecognition.exists_card_coefficient_of_haar_volume line 27

    Source documentation

    A fixed positive ball mass converts a real volume coefficient into a natural cardinal coefficient, uniformly in the scale.

    theorem exists_card_coefficient_of_haar_volume
        (μ : Measure G) [μ.IsHaarMeasure] {r F : ℝ} (hr : 0 < r)
        (b : ℕ) (region : ℕ → Set G)
        (hvol : ∀ n, μ (region n) ≤ ENNReal.ofReal F * (1 + (n : ℝ≥0∞)) ^ b) :
        ∃ C : ℕ, ∀ (n : ℕ) (s : Finset G),
          (∀ x ∈ s, ∀ y ∈ s, x ≠ y → r + r ≤ dist x y) →
          (∀ x ∈ s, ball x r ⊆ region n) → s.card ≤ C * (1 + n) ^ b := by
    …
  2. theorem OAI.PolycyclicRecognition.polynomialBoundedChainPacking_of_nilpotent_exponential line 58

    Source documentation

    Nilpotent chains satisfy the required finite polynomial packing property. This applies to any height map, since the estimate uses just the steps.

    theorem polynomialBoundedChainPacking_of_nilpotent_exponential
        (dynkin : NilpotentDynkinExpansionInput E G)
        (haarInput : NilpotentExponentialHaarInput E G)
        (Exp : GroupLieAlgebra (𝓘(ℝ, E)) G → G) (hExp : IsGroupExponential Exp)
        (hnil : LieRing.IsNilpotent (GroupLieAlgebra (𝓘(ℝ, E)) G))
        {W : Type*} [NormedAddCommGroup W] (π : G → W) :
        PolynomialBoundedChainPacking π := by
    …

    Mentions: OAI.PolycyclicRecognition.NilpotentDynkinExpansionInput, OAI.PolycyclicRecognition.NilpotentExponentialHaarInput, OAI.PolycyclicRecognition.PolynomialBoundedChainPacking