OAI/Geometry/RCD/Heat/GaussianOffDiagonal.lean
5 declarations, 0 contain sorry, 0 declared as axioms
Gaussian decay of the heat kernel away from its pole
- def
OAI.RegularPointCoordinates.gaussianOffDiagonalEnvelopeline 16Source documentation
The envelope after a polynomial lower bound for small ball volume.
def gaussianOffDiagonalEnvelope (s a b t : ℝ) : ℝ := …
- theorem
OAI.RegularPointCoordinates.gaussianOffDiagonalEnvelope_nonnegline 19 - theorem
OAI.RegularPointCoordinates.gaussianOffDiagonalEnvelope_tendstoline 25Source 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
- theorem
OAI.RegularPointCoordinates.gaussianOffDiagonalEnvelope_weighted_tendstoline 39Source 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
- theorem
OAI.RegularPointCoordinates.gaussian_upper_of_inverse_power_volumeline 54Source 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