OAI/Geometry/RCD/Coordinates/AffineFitRecurrence.lean
5 declarations, 0 contain sorry, 0 declared as axioms
The squared affine-fit recurrence and its geometric envelope
- theorem
OAI.RegularPointCoordinates.affine_fit_squared_stepline 13Source documentation
Squaring a single affine-improvement estimate costs a fixed factor, and preserves the Poisson defect without taking its square root.
theorem affine_fit_squared_step {e e' a C P : ℝ} (he : 0 ≤ e) (he' : 0 ≤ e') (ha : 0 ≤ a) (hC : 0 ≤ C) (hP : 0 ≤ P) (hfit : e' ≤ a * e + C * Real.sqrt P) : e' ^ 2 ≤ 2 * a ^ 2 * e ^ 2 + 2 * C ^ 2 * P := by … - theorem
OAI.RegularPointCoordinates.forwardDefect_succline 22 - theorem
OAI.RegularPointCoordinates.forwardDefect_propagatesline 37 - theorem
OAI.RegularPointCoordinates.forwardDefect_strideline 49Source documentation
A stride of
mleaves the final new source term available, even though all intermediate source terms are discarded from the bound.theorem forwardDefect_stride {σ η : ℝ} (hσ : 0 ≤ σ) {P : ℕ → ℝ} (hP : ∀ i, 0 ≤ P i) {m : ℕ} (hm : 0 < m) (i : ℕ) : σ ^ m * forwardDefect σ η P i + P (i + m) ≤ forwardDefect σ η P (i + m) := by … - theorem
OAI.RegularPointCoordinates.affine_fit_le_forwardDefectline 61Source documentation
The same comparison works simultaneously in all residue classes of the affine-improvement stride. This is the discrete step used before the two-sided smoothing in radial pinching.
theorem affine_fit_le_forwardDefect {σ η : ℝ} (hσ : 0 ≤ σ) {P F : ℕ → ℝ} (hP : ∀ i, 0 ≤ P i) {m : ℕ} (hm : 0 < m) (hinitial : ∀ i < m, F i ≤ η * σ ^ i) (hstep : ∀ i, F (i + m) ≤ σ ^ m * F i + P (i + m)) : ∀ i, F i ≤ forwardDefect σ η P i := by …