OAI/GroupTheory/PolycyclicRecognition/Geometry/CanonicalExponentialMeasure.lean

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2 declarations, 0 contain sorry, 0 declared as axioms

Haar properties of the exact measure used by the image-volume formula

  1. theorem OAI.PolycyclicRecognition.exponential_basis_measure_isHaar line 23

    Source documentation

    The published input gives Haar invariance to this specific coordinate measure, so recurrence and the determinant formula use the same normalization.

    theorem exponential_basis_measure_isHaar
        (haar : NilpotentExponentialHaarInput E G)
        (e : L ≃ₗ⁅ℝ⁆ GroupLieAlgebra (𝓘(ℝ, E)) G)
        (hnil : LieRing.IsNilpotent L)
        (Exp : GroupLieAlgebra (𝓘(ℝ, E)) G → G) (hExp : IsGroupExponential Exp)
        {n : ℕ} (b : Basis (Fin n) ℝ L) :
        (Measure.map ((Exp ∘ e) ∘ b.equivFun.symm) volume).IsHaarMeasure := by
    …

    Mentions: OAI.PolycyclicRecognition.NilpotentExponentialHaarInput

  2. theorem OAI.PolycyclicRecognition.exponential_basis_measure_isRightInvariant line 40

    Source documentation

    Inversion corresponds to coordinate negation. Thus the same measure is also right invariant, as required by backward recurrence.

    theorem exponential_basis_measure_isRightInvariant
        (haar : NilpotentExponentialHaarInput E G)
        (e : L ≃ₗ⁅ℝ⁆ GroupLieAlgebra (𝓘(ℝ, E)) G)
        (hnil : LieRing.IsNilpotent L)
        (Exp : GroupLieAlgebra (𝓘(ℝ, E)) G → G) (hExp : IsGroupExponential Exp)
        {n : ℕ} (b : Basis (Fin n) ℝ L) :
        (Measure.map ((Exp ∘ e) ∘ b.equivFun.symm) volume).IsMulRightInvariant := by
    …

    Mentions: OAI.PolycyclicRecognition.NilpotentExponentialHaarInput