OAI/Geometry/RCD/Heat/GaussianOffDiagonal.lean

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5 declarations, 0 contain sorry, 0 declared as axioms

Gaussian decay of the heat kernel away from its pole

  1. def OAI.RegularPointCoordinates.gaussianOffDiagonalEnvelope line 16

    Source documentation

    The envelope after a polynomial lower bound for small ball volume.

    def gaussianOffDiagonalEnvelope (s a b t : ℝ) : ℝ :=
    …
  2. theorem OAI.RegularPointCoordinates.gaussianOffDiagonalEnvelope_nonneg line 19
  3. theorem OAI.RegularPointCoordinates.gaussianOffDiagonalEnvelope_tendsto line 25

    Source documentation

    Every polynomial volume loss is dominated by a positive off-diagonal Gaussian exponent at small time.

    theorem gaussianOffDiagonalEnvelope_tendsto (s b : ℝ) {a : ℝ} (ha : 0 < a) :
        Tendsto (gaussianOffDiagonalEnvelope s a b) (𝓝[>] 0) (𝓝 0) := by
    …

    Mentions: OAI.RegularPointCoordinates.gaussianOffDiagonalEnvelope

  4. theorem OAI.RegularPointCoordinates.gaussianOffDiagonalEnvelope_weighted_tendsto line 39

    Source documentation

    The same error still vanishes after any fixed polynomial loss from an interscale change of normalization.

    theorem gaussianOffDiagonalEnvelope_weighted_tendsto (s b q : ℝ) {a : ℝ} (ha : 0 < a) :
        Tendsto (fun t : ℝ => (t⁻¹) ^ q * gaussianOffDiagonalEnvelope s a b t)
          (𝓝[>] 0) (𝓝 0) := by
    …

    Mentions: OAI.RegularPointCoordinates.gaussianOffDiagonalEnvelope

  5. theorem OAI.RegularPointCoordinates.gaussian_upper_of_inverse_power_volume line 54

    Source documentation

    The exact Gaussian upper bound and a lower volume power produce a uniform off-diagonal envelope. The volume hypothesis is in the inverse power form needed here; it is kept separate from the published bound.

    theorem gaussian_upper_of_inverse_power_volume
        {t s d C₁ C₂ V ε : ℝ} (ht : 0 < t) (hd : 0 ≤ d)
        (hC : 0 < C₁) (hV : 0 < V) (hden : 0 < 4 + ε) (x y : X)
        (hupper : k t x y ≤ (C₁ / μ.real (ball y (Real.sqrt t))) *
          Real.exp (-(dist x y) ^ 2 / ((4 + ε) * t) + C₂ * t))
        (hvol : V / (t⁻¹) ^ s ≤ μ.real (ball y (Real.sqrt t)))
        (hsep : d ≤ dist x y) :
        k t x y ≤ (C₁ / V) * gaussianOffDiagonalEnvelope s (d ^ 2 / (4 + ε)) C₂ t := by
    …

    Mentions: OAI.RegularPointCoordinates.gaussianOffDiagonalEnvelope