OAI/GroupTheory/PolycyclicRecognition/Algebra/GromovGrowthBridge.lean
3 declarations, 0 contain sorry, 0 declared as axioms
Gromov's theorem from Aaron Hill's formalization
Aaron Hill's FormalConjecturesCheck.gromov_forward proves Gromov's
polynomial-growth theorem for arbitrary groups. Its list-defined Cayley balls
agree with the finite word balls used here, and their polynomial bounds
are equivalent without an additional finite-generation or countability hypothesis.
- theorem
OAI.PolycyclicRecognition.cayleyBall_eq_wordBallline 21Source documentation
For symmetric generators the two concrete definitions of word ball agree.
theorem cayleyBall_eq_wordBall (T : Finset J) (hT : ∀ t ∈ T, t⁻¹ ∈ T) (n : ℕ) : FormalConjecturesCheck.CayleyBall (T : Set J) n = (wordBall T n : Set J) := by …Mentions: OAI.PolycyclicRecognition.wordBall
- theorem
OAI.PolycyclicRecognition.growthFunction_eq_card_wordBallline 36Source documentation
The imported theorem's growth function counts exactly our finite ball.
theorem growthFunction_eq_card_wordBall (T : Finset J) (hT : ∀ t ∈ T, t⁻¹ ∈ T) (n : ℕ) : FormalConjecturesCheck.GrowthFunction (T : Set J) n = (wordBall T n).card := by …Mentions: OAI.PolycyclicRecognition.wordBall
- theorem
OAI.PolycyclicRecognition.hasPolynomialGrowth_of_wordBallline 44Source documentation
The positive real constant in the imported growth convention can absorb both the shift by one and a possibly zero natural constant.
theorem hasPolynomialGrowth_of_wordBall (T : Finset J) (hT : ∀ t ∈ T, t⁻¹ ∈ T) (hgen : Subgroup.closure (T : Set J) = ⊤) (hgrowth : ∃ C b : ℕ, ∀ n, (wordBall T n).card ≤ C * (1 + n) ^ b) : FormalConjecturesCheck.HasPolynomialGrowth J := by …Mentions: OAI.PolycyclicRecognition.wordBall