OAI/Geometry/RCD/Metric/CompactDensityTimeIntegral.lean

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2 declarations, 0 contain sorry, 0 declared as axioms

Genuine time integrability for compact L1 sources

  1. theorem OAI.RegularPointCoordinates.average_density_intervalIntegrable_zero line 21

    Source documentation

    The spatial average makes any compact L1 source time-integrable at zero, using only its finite mass and the exact inverse-volume bound.

    theorem average_density_intervalIntegrable_zero (A : Set X)
        (hA : MeasurableSet A) (hAt : μ A ≠ ∞)
        {g : X → ℝ} (hg : Integrable g μ) {K : Set X} (hK : IsCompact K)
        (hz : ∀ᵐ z ∂μ, z ∉ K → g z = 0) {T : ℝ} (hT : 0 ≤ T) :
        IntervalIntegrable (fun t => ∫ z, kernelAverage μ ker t A z * g z ∂μ) volume 0 T := by
    …

    Mentions: OAI.RegularPointCoordinates.kernelAverage

  2. theorem OAI.RegularPointCoordinates.difference_density_intervalIntegrable line 43

    Source documentation

    The difference pairing is integrable on every compact positive-time interval.

    theorem difference_density_intervalIntegrable (A : Set X)
        (hA : MeasurableSet A) (hbounded : Bornology.IsBounded A) (x : X)
        {g : X → ℝ} (hg : Integrable g μ) {K : Set X} (hK : IsCompact K)
        (hz : ∀ᵐ z ∂μ, z ∉ K → g z = 0) {s t : ℝ} (hs : 0 < s) (hst : s ≤ t) :
        IntervalIntegrable (fun τ => ∫ z, (kernelAverage μ ker τ A z - ker τ x z) * g z ∂μ)
          volume s t :=
    …

    Mentions: OAI.RegularPointCoordinates.kernelAverage