OAI/Geometry/RCD/Heat/HeatGramEvolution.lean

GitHub source file

6 declarations, 0 contain sorry, 0 declared as axioms

Evolution of actual cutoff heat Grams

A weak measure Laplacian of the cutoff energy density gives its pointwise heat derivative and the integrated Gram increment. A nonnegative shifted source then implies monotonicity.

  1. def OAI.RegularPointCoordinates.cutoffHeatGramAt line 29

    Source documentation

    An all-time extension used only to state ordinary derivatives at positive times; it agrees with the actual Gram wherever it is used.

    def cutoffHeatGramAt (t : ℝ) (x : X) (lambda : ℝ) : E →L[ℝ] E :=
    …
  2. theorem OAI.RegularPointCoordinates.cutoffHeatGramAt_of_pos line 32
  3. theorem OAI.RegularPointCoordinates.cutoffHeatGram_kernel_energy line 39

    Source documentation

    Identification with the continuous kernel representative, rather than an almost-everywhere choice of the heat flow.

    theorem cutoffHeatGram_kernel_energy (v : E) (f : SobolevSpace μ hQ)
        (hf : SobolevSpace.toLp μ hQ f =ᵐ[μ]
          fun z => χ z * (SobolevSpace.minimalSlope μ hQ (U v) z) ^ 2)
        {t : ℝ} (ht : 0 < t) (x : X) (lambda : ℝ) :
        ⟪v, cutoffHeatGram μ hQ hp hχ hsχ U ht x lambda v⟫_ℝ =
          kernelHeat μ hQ hp t (SobolevSpace.toLp μ hQ f) x + lambda * t * ‖v‖ ^ 2 := by
    …

    Mentions: OAI.RegularPointCoordinates.SobolevSpace, OAI.RegularPointCoordinates.SobolevSpace.toLp, OAI.RegularPointCoordinates.SobolevSpace.minimalSlope, OAI.RegularPointCoordinates.cutoffHeatGram, OAI.RegularPointCoordinates.kernelHeat

  4. theorem OAI.RegularPointCoordinates.cutoffHeatGram_hasDerivAt line 53

    Source documentation

    Full measure-source differentiation of the actual heat Gram.

    theorem cutoffHeatGram_hasDerivAt (v : E) (f : SobolevSpace μ hQ)
        (hf : SobolevSpace.toLp μ hQ f =ᵐ[μ]
          fun z => χ z * (SobolevSpace.minimalSlope μ hQ (U v) z) ^ 2)
        (ν : SignedMeasure X) (hν : IsMeasureLaplacian μ hQ f ν)
        (c : X) {R : ℝ} (hR : 0 < R)
        (hfs : ∀ᵐ z ∂μ, R < dist c z → SobolevSpace.toLp μ hQ f z = 0)
        (hνs : ν.variation (Metric.closedBall c R)ᶜ = 0)
        {t : ℝ} (ht : 0 < t) (x : X) (lambda : ℝ) :
        HasDerivAt (fun s => ⟪v, cutoffHeatGramAt μ hQ hp hχ hsχ U s x lambda v⟫_ℝ)
          ((∫ᵛ z, p t x z ∂<•ν) + lambda * ‖v‖ ^ 2) t := by
    …

    Mentions: OAI.RegularPointCoordinates.SobolevSpace, OAI.RegularPointCoordinates.SobolevSpace.toLp, OAI.RegularPointCoordinates.SobolevSpace.minimalSlope, OAI.RegularPointCoordinates.IsMeasureLaplacian, OAI.RegularPointCoordinates.cutoffHeatGramAt

  5. theorem OAI.RegularPointCoordinates.cutoffHeatGram_sub_eq_integral line 74

    Source documentation

    Integrating the source gives the actual Gram increment between any positive times. No density for the signed source is assumed.

    theorem cutoffHeatGram_sub_eq_integral (v : E) (f : SobolevSpace μ hQ)
        (hf : SobolevSpace.toLp μ hQ f =ᵐ[μ]
          fun z => χ z * (SobolevSpace.minimalSlope μ hQ (U v) z) ^ 2)
        (ν : SignedMeasure X) (hν : IsMeasureLaplacian μ hQ f ν)
        (c : X) {R : ℝ} (hR : 0 < R)
        (hfs : ∀ᵐ z ∂μ, R < dist c z → SobolevSpace.toLp μ hQ f z = 0)
        (hνs : ν.variation (Metric.closedBall c R)ᶜ = 0)
        {s t : ℝ} (hs : 0 < s) (hst : s ≤ t) (x : X) (lambda : ℝ) :
        ⟪v, cutoffHeatGram μ hQ hp hχ hsχ U (hs.trans_le hst) x lambda v⟫_ℝ -
          ⟪v, cutoffHeatGram μ hQ hp hχ hsχ U hs x lambda v⟫_ℝ =
          (∫ r in s..t, (∫ᵛ z, p r x z ∂<•ν)) + lambda * (t - s) * ‖v‖ ^ 2 := by
    …

    Mentions: OAI.RegularPointCoordinates.SobolevSpace, OAI.RegularPointCoordinates.SobolevSpace.toLp, OAI.RegularPointCoordinates.SobolevSpace.minimalSlope, OAI.RegularPointCoordinates.IsMeasureLaplacian, OAI.RegularPointCoordinates.cutoffHeatGram

  6. theorem OAI.RegularPointCoordinates.cutoffHeatGram_monotone line 92

    Source documentation

    Positivity of the shifted source gives monotonicity of the actual quadratic heat Gram on positive times.

    theorem cutoffHeatGram_monotone (v : E) (f : SobolevSpace μ hQ)
        (hf : SobolevSpace.toLp μ hQ f =ᵐ[μ]
          fun z => χ z * (SobolevSpace.minimalSlope μ hQ (U v) z) ^ 2)
        (ν : SignedMeasure X) (hν : IsMeasureLaplacian μ hQ f ν)
        (c : X) {R : ℝ} (hR : 0 < R)
        (hfs : ∀ᵐ z ∂μ, R < dist c z → SobolevSpace.toLp μ hQ f z = 0)
        (hνs : ν.variation (Metric.closedBall c R)ᶜ = 0)
        (x : X) (lambda : ℝ)
        (hpos : ∀ t, 0 < t → 0 ≤ (∫ᵛ z, p t x z ∂<•ν) + lambda * ‖v‖ ^ 2)
        {s t : ℝ} (hs : 0 < s) (hst : s ≤ t) :
        ⟪v, cutoffHeatGram μ hQ hp hχ hsχ U hs x lambda v⟫_ℝ ≤
          ⟪v, cutoffHeatGram μ hQ hp hχ hsχ U (hs.trans_le hst) x lambda v⟫_ℝ := by
    …

    Mentions: OAI.RegularPointCoordinates.SobolevSpace, OAI.RegularPointCoordinates.SobolevSpace.toLp, OAI.RegularPointCoordinates.SobolevSpace.minimalSlope, OAI.RegularPointCoordinates.IsMeasureLaplacian, OAI.RegularPointCoordinates.cutoffHeatGram