OAI/GroupTheory/PolycyclicRecognition/Geometry/ExponentialCellMass.lean

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2 declarations, 0 contain sorry, 0 declared as axioms

Positive finite mass of the actual translated exponential cells

  1. theorem OAI.PolycyclicRecognition.translated_exponential_cell_mass line 15

    Source documentation

    Every positive finite coordinate cell gives a positive finite Haar cell, with no restriction on the scale or the deterministic right suffix.

    theorem translated_exponential_cell_mass
        {L E N I : Type*} [LieRing L] [LieAlgebra ℝ L]
        [NormedAddCommGroup E] [NormedSpace ℝ E] [FiniteDimensional ℝ E]
        [TopologicalSpace N] [ChartedSpace E N] [Group N]
        [LieGroup (𝓘(ℝ, E)) ⊤ N] [T2Space N] [SimplyConnectedSpace N]
        [MeasurableSpace N] [BorelSpace N]
        (haar : NilpotentExponentialHaarInput E N)
        (e : L ≃ₗ⁅ℝ⁆ GroupLieAlgebra (𝓘(ℝ, E)) N) (hnil : LieRing.IsNilpotent L)
        (Exp : GroupLieAlgebra (𝓘(ℝ, E)) N → N) (hExp : IsGroupExponential Exp)
        (chart : GroupLieAlgebra (𝓘(ℝ, E)) N ≃ₜ N) (hchart : ∀ x, chart x = Exp x)
        (X : I → L) (words : Finset (FreeMagma I))
        (b₀ : Basis (Fin (finrank ℝ L)) ℝ L) (β : WordBasisSelections X words)
    …

    Mentions: OAI.PolycyclicRecognition.NilpotentExponentialHaarInput, OAI.PolycyclicRecognition.WordBasisSelections

  2. theorem OAI.PolycyclicRecognition.coordinate_cube_mass line 57

    Source documentation

    The finite-dimensional closed coordinate cube has positive finite mass.

    theorem coordinate_cube_mass {n : ℕ} {R : ℝ} (hR : 0 < R) :
        volume (Icc (fun _ : Fin n => -R) (fun _ => R)) ≠ 0 ∧
          volume (Icc (fun _ : Fin n => -R) (fun _ => R)) ≠ ∞ := by
    …