OAI/GroupTheory/PolycyclicRecognition/Analysis/ProbeCellVolume.lean

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2 declarations, 0 contain sorry, 0 declared as axioms

Positive probe probabilities give actual endpoint volume

  1. theorem OAI.PolycyclicRecognition.cellProbabilityMeasure_prod line 16

    Source documentation

    Independent uniform sampling on two finite cells is uniform sampling on their product, with the exact product Haar normalization.

    theorem cellProbabilityMeasure_prod
        {X Y : Type*} [MeasurableSpace X] [MeasurableSpace Y]
        (μ : Measure X) (ν : Measure Y) [SFinite μ] [SFinite ν]
        (A : Set X) (B : Set Y) (hA0 : μ A ≠ 0) (hAt : μ A ≠ ⊤)
        (hB0 : ν B ≠ 0) (hBt : ν B ≠ ⊤) :
        (cellProbabilityMeasure μ A hA0 hAt : Measure X).prod
            (cellProbabilityMeasure ν B hB0 hBt : Measure Y) =
          ((μ.prod ν) (A ×ˢ B))⁻¹ • (μ.prod ν).restrict (A ×ˢ B) := by
    …

    Mentions: OAI.PolycyclicRecognition.cellProbabilityMeasure

  2. theorem OAI.PolycyclicRecognition.probe_cell_image_volume_lower line 30

    Source documentation

    A positive fraction of the original cell becomes a corresponding amount of actual volume under the section-coordinate embedding.

    theorem probe_cell_image_volume_lower
        {X Y : Type*} [MeasurableSpace X] [MeasurableSpace Y]
        (μ : Measure X) (e : X → Y) (he : MeasurableEmbedding e)
        (A K : Set X) (hA0 : μ A ≠ 0) (hAt : μ A ≠ ⊤)
        (hK : MeasurableSet K) (hKA : K ⊆ A)
        {c : ℝ} (hc : 0 ≤ c)
        (hmass : ENNReal.ofReal c ≤ (cellProbabilityMeasure μ A hA0 hAt : Measure X) K) :
        c * (μ A).toReal ≤ ((Measure.map e μ) (e '' K)).toReal := by
    …

    Mentions: OAI.PolycyclicRecognition.cellProbabilityMeasure