OAI/NumberTheory/DukePrimeDegree/Dynamics/CorrectedGenericPairs.lean

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3 declarations, 0 contain sorry, 0 declared as axioms

Simultaneous generic representatives of a transverse pair

A correction in a block-preserving subgroup may depend on the pair. The Haar-fiber selection puts both corrected points back in the same generic set, and simultaneous block conjugation preserves the scalar within-block normalization. The subgroup is contained in the actual measure stabilizer in the application; that inclusion is explicit here.

  1. lemma OAI.DukePrimeDegree.measurable_rightAction_subgroup_uncurry line 23
  2. theorem OAI.DukePrimeDegree.exists_actual_stabilizer_fiber_good_set line 30

    Source documentation

    The finite-patch enlargement uses invariance of the ambient measure under its actual stabilizer, without selecting an ergodic time-one map.

    theorem exists_actual_stabilizer_fiber_good_set {n : ℕ}
        (μ : Measure (X n)) [IsProbabilityMeasure μ]
        (H : Subgroup (G n)) (hH : H ≤ invariantRightSubgroup μ)
        (ρ : Measure H) [SFinite ρ] (K : Set H)
        (G₀ : Set (X n)) (hG₀ : MeasurableSet G₀)
        (a : ℝ≥0∞) (ha : a ≠ 0) (hatop : a ≠ ⊤) :
        ∃ E : Set (X n), MeasurableSet E ∧
          μ Eᶜ ≤ (ρ K * μ G₀ᶜ) / a ∧
          ∀ x ∈ E,
            badOrbitFiberMass ρ (fun y h => rightAction y (h : G n)) K G₀ x < a := by
    …

    Mentions: OAI.DukePrimeDegree.badOrbitFiberMass

  3. theorem OAI.DukePrimeDegree.exists_corrected_generic_pair line 48

    Source documentation

    Algebraic and generic-set properties hold for the very same common translation. The selected translation lies in the prescribed bounded patch; it is not an extra independent limit or invariance hypothesis.

    theorem exists_corrected_generic_pair {n : ℕ}
        (L H : Subgroup (G n)) (hHL : H ≤ L)
        (r : Setoid (Fin n)) (hblock : H ≤ blockMatrixGroup r)
        (ρ : Measure H) [ρ.IsMulLeftInvariant]
        (K₀ K₁ : Set H) (hK : K₀ ⊆ K₁)
        (G₀ : Set (X n)) (hG₀ : MeasurableSet G₀)
        (x : X n) (a : G n) (ha : a ∉ L) (b : H)
        (hb : ∀ h ∈ K₀, b * h ∈ K₁)
        (c : ℝ)
        (hpart : withinBlockPart r (a * (b : G n)).val = Matrix.diagonal (fun _ => c))
        (hsmall :
          badOrbitFiberMass ρ (fun y h => rightAction y (h : G n)) K₁ G₀ x +
    …

    Mentions: OAI.DukePrimeDegree.blockMatrixGroup, OAI.DukePrimeDegree.withinBlockPart, OAI.DukePrimeDegree.badOrbitFiberMass