OAI/GroupTheory/PolycyclicRecognition/Geometry/WeightedWordBound.lean
1 declarations, 0 contain sorry, 0 declared as axioms
Word-length control by a weighted norm
Short-cost factors are accumulated until they leave a small identity ball. Each completed block has bounded word length and pays for that length.
- theorem
OAI.PolycyclicRecognition.seminorm_product_cost_boundline 22Source documentation
The residual factor stays in the small ball; every flushed block is charged against the accumulated cost.
theorem seminorm_product_cost_bound (p w : GroupSeminorm G) (c : G → ℝ≥0) {δ : ℝ} (hδ : 0 < δ) (hδ1 : δ ≤ 1) (hpc : ∀ g, p g ≤ c g) (hlocal : ∀ g, p g ≤ δ → w g ≤ 1) (hwc : ∀ g, w g ≤ max 1 (c g : ℝ)) (l : List G) : w l.prod ≤ (4 / δ) * (productCost c l : ℝ) + 1 := by …Mentions: OAI.PolycyclicRecognition.productCost