OAI/GroupTheory/PolycyclicRecognition/Geometry/CenteredHeightError.lean
3 declarations, 0 contain sorry, 0 declared as axioms
Sublinear height errors after changing the basepoint
- theorem
OAI.PolycyclicRecognition.centered_height_sublinearline 15Source documentation
The same linear coefficient works after centering the coarse map at any fixed source point. Only the additive sublinear-error constant changes.
theorem centered_height_sublinear (π : G →* Multiplicative W) (A : W →L[ℝ] W) (f : G → G) (hsub : ∀ ε : ℝ, 0 < ε → ∃ B : ℝ, 0 ≤ B ∧ ∀ g, ‖(π (f g)).toAdd - A ((π g).toAdd)‖ ≤ ε * dist 1 g + B) (x : G) : ∀ ε : ℝ, 0 < ε → ∃ B : ℝ, 0 ≤ B ∧ ∀ g, ‖(π ((f x)⁻¹ * f (x * g))).toAdd - A ((π g).toAdd)‖ ≤ ε * dist 1 g + B := by … - theorem
OAI.PolycyclicRecognition.centered_coarse_lipschitzline 44Source documentation
Centering also preserves the coarse Lipschitz constants exactly.
theorem centered_coarse_lipschitz (f : G → G) {L C : ℝ} (hf : ∀ a b, dist (f a) (f b) ≤ L * dist a b + C) (x a b : G) : dist ((f x)⁻¹ * f (x * a)) ((f x)⁻¹ * f (x * b)) ≤ L * dist a b + C := by … - theorem
OAI.PolycyclicRecognition.absolute_height_sublinear_of_centered_uniformline 53Source documentation
Uniform centered height control supplies the absolute sublinear estimate used in representative independence.
theorem absolute_height_sublinear_of_centered_uniform (π : G →* Multiplicative W) (A : W →L[ℝ] W) (f : G → G) (hsub : ∀ ε : ℝ, 0 < ε → ∃ B : ℝ, 0 ≤ B ∧ ∀ x g, ‖(π ((f x)⁻¹ * f (x * g))).toAdd - A ((π g).toAdd)‖ ≤ ε * dist 1 g + B) : ∀ ε : ℝ, 0 < ε → ∃ B : ℝ, 0 ≤ B ∧ ∀ g, ‖(π (f g)).toAdd - A ((π g).toAdd)‖ ≤ ε * dist 1 g + B := by …